MEI Pharma, Inc. - Annual Report: 2013 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended June 30, 2013

OR

For the transition period from                      to                     .

Commission File Number: 000-50484

MEI Pharma, Inc.

(Exact name of registrant as specified in its charter)

11975 El Camino Real, Suite 101, San Diego, CA 92130

(Address of principal executive offices) (Zip Code)

(858) 792-6300

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

None

(Title of Class)

Indicate by a check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.     Yes  ¨    No  x

Indicate by a check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.     Yes  ¨    No  x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.     Yes   x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).     Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (Section 229.405 of this chapter) is not contained herein, and will not be contained, to the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “large accelerated filer, “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     Yes  ¨    No  x

The aggregate market value of the voting common equity held by non-affiliates of the registrant was approximately $52.7 million as of December 31, 2012, based on the closing price of the registrant’s Common Stock as reported on the NASDAQ Capital Market on such date.

As of September 13, 2013, there were 17,116,662 shares of the registrant’s common stock, par value $0.00000002 per share, outstanding.

Table of Contents

MEI PHARMA, INC.

TABLE OF CONTENTS

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Forward-Looking Statements

This Annual Report on Form 10-K includes forward-looking statements, which involve a number of risks and uncertainties. These forward-looking statements can generally be identified as such because the context of the statement will include words such as “may,” “will,” “intend,” “plan,” “believe,” “anticipate,” “expect,” “estimate,” “predict,” “potential,” “continue,” “likely,” or “opportunity,” the negative of these words or other similar words. Similarly, statements that describe our future plans, strategies, intentions, expectations, objectives, goals or prospects and other statements that are not historical facts are also forward-looking statements. Discussions containing these forward-looking statements may be found, among other places, in “Business” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in this Annual Report on Form 10-K. For such statements, we claim the protection of the Private Securities Litigation Reform Act of 1995. Readers of this Annual Report on Form 10-K are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the time this Annual Report on Form 10-K was filed with the Securities and Exchange Commission, or SEC. These forward-looking statements are based largely on our expectations and projections about future events and future trends affecting our business, and are subject to risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements. These risks and uncertainties include, without limitation, those discussed in “Risk Factors” and in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of this Annual Report on Form 10-K. In addition, past financial or operating performance is not necessarily a reliable indicator of future performance, and you should not use our historical performance to anticipate results or future period trends. We can give no assurances that any of the events anticipated by the forward-looking statements will occur or, if any of them do, what impact they will have on our results of operations and financial condition. Except as required by law, we undertake no obligation to update publicly or revise our forward-looking statements to reflect events or circumstances that arise after the filing of this Annual Report on Form 10-K.

In this Annual Report on Form 10-K, “MEI Pharma,” “we,” “us” and “our” refer to MEI Pharma, Inc. and our former wholly owned subsidiary Marshall Edwards Pty Ltd. (“MEPL”), which was dissolved in April 2012.

All financial data and share information in this Annual Report on Form 10-K has been presented on an as-adjusted basis to give effect to our December 2012 1-for-6 reverse stock split.

PART I

Overview

We are a development-stage oncology company focused on the clinical development of novel small molecules for the treatment of cancer. We were incorporated in Delaware in 2000 as a wholly owned subsidiary of Novogen Limited (“Novogen”). Our common stock is listed on the Nasdaq Capital Market under the symbol “MEIP”. In December 2012, Novogen distributed to its shareholders substantially all of its MEI Pharma common stock.

Our business purpose is the development of drugs for the treatment of cancer. We are principally focused on the clinical development of our lead drug candidate, Pracinostat, which we are currently investigating in a Phase II clinical trial. Pracinostat is an orally available histone deacetylase (HDAC) inhibitor that is currently being developed for advanced hematologic diseases such as myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In August 2012, we completed the acquisition of certain assets and intellectual property, including those related to Pracinostat, from S*Bio Pte Ltd (“S*Bio”). Our clinical development pipeline also includes two isoflavone-based drug candidates, ME-344 and ME-143. ME-344 and ME-143 are derived from an isoflavone technology platform that has generated a number of compounds with anti-tumor activity in laboratory

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studies. These compounds have been shown to interact with specific targets resulting in the inhibition of tumor metabolism, a function critical for cancer cell survival. ME-344 is currently being investigated in a Phase I clinical trial.

We own exclusive worldwide rights to all of our drug candidates, including Pracinostat, ME-344 and ME-143.

Clinical Development Programs

Lead Drug Candidate: Pracinostat

We are principally focused on the clinical development of our lead drug candidate, Pracinostat. Pracinostat is an orally available selective inhibitor of a group of enzymes called histone deacetylases, or HDACs. HDACs belong to a larger set of proteins collectively known as epigenetic regulators that can alter gene expression by chemically modifying DNA or its associated chromosomal proteins. Abnormal activity of these regulators is believed to play an important role in cancer and other diseases. There are currently two HDAC inhibitors – one oral and one injectable – approved by the U.S. Food and Drug Administration (FDA) for the treatment of T-cell lymphoma.

Pracinostat has been tested in multiple Phase I and Phase II clinical trials in advanced hematologic malignancies, such as MDS, AML and myelofibrosis, as well as in solid tumor indications in both adult and pediatric patients. Pracinostat has been generally well tolerated in more than 200 patients to date, with readily manageable side effects often associated with drugs of this class. The results of these studies also suggest that Pracinostat has potential best-in-class pharmacokinetic properties when compared to other oral HDAC inhibitors, including the late-stage drug candidate, Panobinostat, as well as the approved drug, Zolinza^® (vorinostat).

Pracinostat has demonstrated clinical evidence of single-agent activity in patients with AML and myelofibrosis. In a Phase I dose-escalation trial in patients with AML, 14% of evaluable patients (two out of 14) achieved a complete response (CR), with the responses enduring for more than 206 and 362 days, respectively. These results were presented at the American Society of Hematology (ASH) Annual Meeting in December 2010. In a Phase II clinical trial in intermediate or high-risk myelofibrosis, 36% of patients (eight of 22) demonstrated clinical benefit from Pracinostat treatment, with 9% of patients (two out of 22) having a clinical improvement (anemia response) and 27% (six of 22) experiencing some reduction in splenomegaly. These results were published in the September 2012 issue of Leukemia Research.

Pracinostat has also shown evidence of synergistic activity when used in combination with the hypomethylating agent, Vidaza^® (azacitidine), in patients with advanced MDS. Results from a pilot Phase II trial presented at the ASH Annual Meeting in December 2012 showed an overall response rate (CR+CRi+PR) of 89% (eight out of nine) among the nine patients treated at the MD Anderson Cancer Center. An additional patient treated at the University of Wisconsin-Madison achieved a complete response, increasing the overall response rate in the trial to 90% (nine out of 10).

In June 2013, we initiated a blinded, placebo-controlled Phase II clinical trial of Pracinostat in combination with Vidaza in patients with previously untreated intermediate-2 or high-risk MDS. The multicenter trial is expected to enroll 100 patients with a one-to-one randomization. Completion of enrollment is anticipated by June 2014 with topline data expected in December 2014. The primary endpoint of the study is complete remission (CR). Secondary endpoints include overall response rate (CR+CRi+PR), hematologic improvement, duration of response, progression-free survival, rate of leukemic transformation, overall survival and safety.

In addition, we are preparing for two open-label Phase II trials of Pracinostat: one in combination with Vidaza in elderly patients with AML who are not suited for induction therapy, expected to initiate in the fall of 2013, and the other in combination with Vidaza or Dacogen^® (decitabine) in patients with hypomethylating agent refractory MDS soon thereafter.

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NADH Oxidase Drug Candidate: ME-143

ME-143 is our next-generation NADH oxidase inhibitor drug candidate. The first-generation compound, Phenoxodiol, was administered to more than 400 patients in clinical studies via oral or intravenous routes. In a Phase II clinical trial of intravenously administered Phenoxodiol in combination with platinum-based chemotherapy in women with recurrent ovarian cancer, a clinical response was observed in 19% of patients (three out of 16). These results were published in the May 2011 issue of International Journal of Gynecological Cancer. However, in a subsequent Phase III trial of orally administered Phenoxodiol in combination with platinum-based chemotherapy, only one out of 142 women with recurrent ovarian cancer achieved a clinical response, suggesting that inefficient levels of active drug are achieved when Phenoxodiol is administered orally. ME-143 has demonstrated superior anti-tumor activity against a number of tumor cell lines compared to Phenoxodiol. In addition to broad single-agent activity, ME-143 has also shown a far superior ability to enhance the cytotoxic effects of chemotherapy in pre-clinical studies. Data from a Phase I trial of ME-143 in heavily treated patients with solid refractory tumors showed that the pharmacokinetic profile of intravenous ME-143 resulted in drug levels that were approximately 30 times higher than the exposure achieved in the Phase II trial of intravenous Phenoxodiol. These results were presented at the American Society of Clinical Oncology Annual Meeting in June 2012.

Mitochondrial Inhibitor Drug Candidate: ME-344

ME-344 is our next-generation mitochondrial inhibitor and an active metabolite of NV-128, the first-generation compound. In April 2011, data from a pre-clinical study of NV-128 were presented at the American Association for Cancer Research Annual Meeting demonstrating its ability to induce mitochondrial instability, ultimately leading to cell death in otherwise chemotherapy-resistant ovarian cancer stem cells. These results were later published in the August 2011 issue of Molecular Cancer Therapeutics. In additional pre-clinical studies, ME-344 demonstrated superior anti-tumor activity against a broad range of human cancer cell lines compared to NV-128.

A first-in-human, dose-escalation study of intravenous ME-344 in patients with solid refractory tumors was initiated in April 2012. The dose-escalation trial is evaluating the safety and tolerability of ME-344. Dose limiting toxicities consistent with the presumed mechanism of action of ME-344 in targeting the mitochondria were reached at 20mg/kg and the maximum tolerated dose has been established at 10 mg/kg. In addition, this single-agent trial is designed to characterize the pharmacokinetic profile of intravenous ME-344 and describe any preliminary clinical anti-tumor activity observed. Enrollment in this study was completed in March 2013. As of September 2013, a number of patients are still being followed in the trial, with disease control ranging from five months to one year. Results from the trial are expected during the fourth quarter of calendar year 2013.

Scientific Overview

HDAC Program

Histone deacetylases (HDACs) play a key role in epigenetic regulation of gene expression by regulating chromatin structure. Acetylation of positively charged lysine residues present in histone proteins by the histone acetyltransferase (HATs) reduces the affinity between histones and negatively charged DNA, resulting in the opening of the chromatin structure. This makes it easier for the transcriptional machinery to access the DNA, enhancing RNA transcription. Conversely, deacetylation by the HDACs closes the chromatin structure leading to a repression of gene transcription. In normal cells, HDACs and HATs together control histone acetylation levels to maintain a balance. In diseases such as cancer, this regulation can be disturbed. HDAC inhibitors cause accumulation of acetylated histones, enhance transcription and result in changes of a variety of cellular responses including differentiation, proliferation, migration, survival and response to metabolic and hypoxic stress. In general, tumor cells are more susceptible than normal cells to the anti-proliferative and pro-apoptotic effects of HDAC inhibitors.

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There are currently two HDAC inhibitors – one oral and one injectable – approved by the FDA for the treatment of T-cell lymphoma. Other HDAC inhibitors are being evaluated in clinical trials as single agents and in combination with chemotherapy for various hematologic diseases, including acute myeloid leukemia, myelodysplastic syndrome (MDS) and myelofibrosis, as well as for solid tumors.

Pracinostat

Our lead drug candidate in this program, Pracinostat, is an orally available, potent HDAC inhibitor with potentially improved physicochemical, pharmaceutical and pharmacokinetic properties when compared to other compounds of this class, including increased bioavailability and increased half-life.

Pracinostat has been tested in more than 200 patients in multiple Phase I and Phase II clinical trials and found to be generally well tolerated with readily manageable side effects often associated with drugs of this class. Results from a Phase I dose-escalation study, presented at the ASH Annual Meeting in December 2010, demonstrated clinical evidence of single-agent activity in patients with AML. In addition, data from a Phase II clinical trial of Pracinostat showed single-agent activity in patients with intermediate or high-risk myelofibrosis. These results were published in the September 2012 issue of Leukemia Research.

Pracinostat has also shown evidence of activity when used in combination with a wide range of therapies in clinical and pre-clinical studies. Pre-clinical data published in the May 2012 issue of Blood Cancer Journal demonstrated synergistic activity when Pracinostat was combined with Pacritinib, an experimental JAK2 inhibitor. In addition, encouraging preliminary results were observed in a pilot Phase II clinical trial of Pracinostat in combination with Vidaza in patients with advanced MDS. These results were presented at the ASH Annual Meeting in December 2012.

Isoflavone-based Programs

Our Company was originally formed to develop novel cancer therapeutics based on a group of compounds known as isoflavones. More than 400 new chemical structures were created based on the central design of these naturally occurring plant isoflavones. We believe that some of these synthetic compounds, including our drug candidates ME-344 and ME-143, interact with specific enzyme targets, resulting in the inhibition of tumor cell metabolism, a function critical for the survival of cancer cells.

Phenoxodiol

The mechanism of action for our first-generation NADH oxidase inhibitor, Phenoxodiol, is suggested, in part, by a discovery from a research team at Purdue University in Indiana. This team has a long-standing research interest in a family of cell surface proteins that are involved in electron transport across the cell membrane enabling hydrogen ion (proton) export at a controlled rate. One of the key components of this proton pump mechanism is a family of cell surface proteins known as NADH oxidases. These proteins are situated on the outside of the cell membrane and regulate the flow of waste hydrogen across the cell membrane. The laboratory studies at Purdue University have shown that a variant form of the surface oxidase, which promotes more rapid hydrogen export, is preferentially expressed on cancer cells, although similar oxidase activity has been identified on small numbers of non-cancer cells undergoing rapid cell division.

Phenoxodiol and our next-generation NADH oxidase inhibitor, ME-143, are able to bind to and inhibit the activity of these oxidase variants, with the resulting inhibition of hydrogen ion removal (H+ efflux) from these cells. This inhibition leads to an extensive disruption to cell signaling pathways and to eventual inhibition of cell proliferation and activation of apoptosis, the process of programmed cell death by which a cell dies naturally. Phenoxodiol and ME-143 appear to have little or no effect on the form of oxidase present on normal healthy cells, providing an explanation for how Phenoxodiol selectively targets cancer cells. Independent research at the Malaghan Institute of Medical Research at Victoria University in New Zealand has confirmed that Phenoxodiol and ME-143 inhibit plasma membrane electron transport in cancer cells, as well as in some other dividing cells.

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Treatment of cancer cells with Phenoxodiol is associated with down regulation of a key signal transduction molecule, sphingosine kinase. Sphingosine kinase is a terminal component of the plasma membrane sphingomyelin pathway leading to the formation of sphingosine-1-phosphate (S1P), a bioactive lipid and a key pro-survival secondary messenger acting via the signal transduction protein kinase, Akt. Two important biological outcomes resulting from the down regulation of sphingosine kinase are (i) cytostasis (i.e., the prevention of the growth and multiplication of cells), and (ii) apoptosis (i.e., programmed cell death) through inhibition of phosphorylation (i.e., addition of a phosphate group) of the anti-apoptotic factors, XIAP (inhibitor of apoptosis protein) and FLIPshort (caspase-8 inhibitory protein). These processes facilitate activation of executioner caspases (proteins that cause the cell to undergo programmed cell death) and restore the activity of the Fas ligand (FasL) family of death receptors. Laboratory studies conducted in collaboration with Yale University suggest one mechanism by which this chain of biochemical events following exposure of tumor cells to Phenoxodiol may also explain how Phenoxodiol is able to sensitize tumor cells to standard anti-cancer drugs such as platinums, gemcitabine and taxanes, on the basis that FLIPshort protein is responsible for inhibiting the sensitivity of the FasL protein (death receptor) to the toxic signaling mediated via these drugs.

Phenoxodiol appears to restore sensitivity to these drugs in cells such as ovarian cancer cells that have acquired resistance. In addition, pre-treatment of tumor cells with Phenoxodiol considerably increases the sensitivity of non-resistant tumor cells to the cytotoxic effects of standard chemotherapy drugs in laboratory research studies. These effects are achieved without increasing the cellular toxicity of the standard chemotherapy drugs to non-tumor cells.

Our drug candidates ME-143 and ME-344 are analogues of Phenoxodiol, but exhibit some differences from Phenoxodiol. In parallel with Phenoxodiol, these drug candidates display pre-clinical anti-cancer activity across a broad range of tumor types, high selectivity for cancer cells, and the ability to chemosensitize tumor cells to the cytotoxic effects of most standard chemotoxic drugs. However, these drug candidates differ from Phenoxodiol in inducing cell death by both caspase-dependent and caspase-independent mechanisms.

ME-143

ME-143 is a highly potent, pan acting investigational anti-cancer drug that demonstrates superior anti-tumor activity against a broad range of tumor cell lines compared to Phenoxodiol. In addition to being more active as a single agent, ME-143 appears to be superior in its ability to synergize with platinum-based chemotherapies, including cisplatin and carboplatin. In a Phase I clinical trial, ME-143 was shown to be generally well tolerated with minimal toxicity as a single agent in heavily treated patients with solid refractory tumors.

ME-344

ME-344 is the active metabolite of a first generation compound, named NV-128. The proposed target for NV-128 and ME-344 is found in the tumor cell mitochondria, the specialized area in the cell that produces energy in the form of adenosine triphosphate (ATP). When these compounds interact with their target, a rapid reduction in ATP occurs, which leads to a cascade of biochemical events within the cell and ultimately to cell death. One outcome that is believed to be critical for cell death induction by ME-344 is the disruption of both mammalian target of rapamycin (mTOR1 and mTOR2) pathways. In cancer cells, the mTOR protein is involved in enhancing tumor growth and may be associated with resistance to chemotherapeutic drugs. Inhibition of both mTOR pathways appears to shut down many of the cellular survival pathways of cancer cells. ME-344 has demonstrated broad activity against a panel of human cancer cell lines both as a single agent and as a chemosensitizing agent. Results from ongoing laboratory research studies conducted in collaboration with the Department of Obstetrics, Gynecology, and Reproductive Sciences at the Yale School of Medicine demonstrate that NV-128 and ME-344 are active against chemotherapy-resistant ovarian tumor stem cells. In April 2011, at the American Association for Cancer Research Annual Meeting, Dr. Alvero from the Yale School of Medicine presented pre-clinical data demonstrating the ability of NV-128 to induce mitochondrial instability, ultimately

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leading to cell death in chemotherapy-resistant ovarian cancer stem cells. This cell death was associated with the activation of the MEK/ERK pathway leading to mitochondrial depolarization and DNA fragmentation. The study further characterized the mechanism of action of NV-128 and demonstrated that NV-128 also promotes a state of cellular starvation, resulting in the activation of the AMP kinase pathway, leading to inhibition of both mTOR pathways and the induction of destructive autophagy. In April 2013, Dr. Alvero presented new data at the AACR Annual Meeting in Washington, DC showing the ability of ME-344 to decrease tumor burden and delay recurrence in a pre-clinical in vivo model of recurrent epithelial ovarian cancer, the most lethal of all gynecologic malignancies. A first-in-human Phase I clinical trial of intravenous ME-344 in patients with solid refractory tumors is ongoing.

Competition

The marketplace for our drug candidates is highly competitive. A number of other companies have products or drug candidates in various stages of pre-clinical or clinical development that are intended for the same therapeutic indications for which our drug candidates are being developed. Some of these potential competing drugs are further advanced in development than our drug candidates and may be commercialized sooner. Even if we are successful in developing effective drugs, our drug candidates may not compete successfully with products produced by our competitors.

Our competitors include pharmaceutical companies and biotechnology companies, as well as universities and public and private research institutions. In addition, companies active in different but related fields represent substantial competition for us. Many of our competitors developing oncology drugs have significantly greater capital resources, larger research and development staffs and facilities, and greater experience in drug development, regulation, manufacturing, and marketing than we do. They compete with us in recruiting eligible patients to participate in clinical studies and in attracting partners for joint ventures. They also license technologies that are competitive with our technologies. As a result, our competitors may be able to more easily develop technologies and products that would render our technologies or our drug candidates obsolete or non-competitive.

Relationship with Novogen

Novogen was our majority shareholder from our inception through December 3, 2012. On such date, Novogen completed the distribution of substantially all of its MEI Pharma common stock to its shareholders. Historically, we licensed from Novogen the rights to Novogen’s patents and applications for our isoflavone-based drug candidates, as well as other compounds. Additionally, Novogen historically was a source of capital, and provided research and development services and administrative and finance services to us under service agreements. The license agreements were terminated in May 2011 in conjunction with our purchase of a portfolio of isoflavone-related assets from Novogen, which we refer to as the “Isoflavone Transaction”. The service agreements were terminated in December 2010.

Intellectual Property

We own worldwide rights to all of our drug candidates. Our intellectual property portfolio includes 14 issued U.S. patents and more than 125 issued foreign patents.

We have acquired patents and patent applications (collectively, “intellectual property” or “IP”), including Pracinostat, from S*Bio relating to a family of heterocyclic compounds that inhibit histone deacetylases (HDAC). The USPTO has issued two patents covering a number of these heterocyclic-based compounds, including Pracinostat, and their pharmaceutical compositions, with patent expiration dates starting in 2026. We anticipate that this IP will be useful in our efforts to develop, market and commercialize the HDAC inhibitor compounds, including Pracinostat, as anti-cancer agents.

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We have also acquired patents and patent applications from Novogen, which relate to a large family of compounds with potentially broad ranging therapeutic effects. We anticipate that this IP will be useful in our efforts to develop, market and commercialize the isoflavonoid compounds, including ME-344 and ME-143, as anti-cancer agents.

In December 2011, the U.S. Patent and Trademark Office (USPTO) issued a new patent covering a number of our isoflavone-based compounds, including ME-344 and ME-143, and their pharmaceutical compositions until March 2027. In January 2012, we announced the issuance of a new method of use patent covering our mitochondrial inhibitor compounds, including ME-344, for the treatment of cancer. Similarly, in April 2012, the USPTO issued a method patent covering ME-143 for use in treating cancer. Each of the new method of use patents are expected to provide protection until September 2025.

As most patent applications in the U.S. are maintained as confidential until published by the U.S. Patent and Trademark Office at 18 months from filing for all cases filed after November 29, 2000, or at issue, for cases filed prior to November 29, 2000, we cannot be certain that we or Novogen were the first to make the inventions covered by the patents and applications referred to above. Additionally, publication of discoveries in the scientific or patent literature often lags behind the actual discoveries. Moreover, pursuant to the terms of the Uruguay Round Agreements Act, patents filed on or after June 8, 1995 have a term of twenty years from the date of such filing except for provisional applications, irrespective of the period of time it may take for such patent to ultimately issue. This may shorten the period of patent protection afforded to therapeutic uses of Pracinostat, ME-344 or ME-143, as patent applications in the biopharmaceutical sector often take considerable time to issue. However, in some countries the patent term may be extended.

In order to protect the confidentiality of our technology, including trade secrets and know-how and other proprietary technical and business information, we require all of our consultants, advisors and collaborators to enter into confidentiality agreements that prohibit the use or disclosure of information that is deemed confidential. The agreements also oblige our consultants, advisors and collaborators to assign to us developments, discoveries and inventions made by such persons in connection with their work with us relating to our products. We cannot be sure that confidentiality will be maintained or disclosure prevented by these agreements or from those from whom we have acquired technology. We also cannot be sure that our proprietary information or intellectual property will be protected by these agreements or that others will not independently develop substantially equivalent proprietary information or intellectual property.

The pharmaceutical industry is highly competitive and patents may have been applied for by, and issued to, other parties relating to products competitive with Pracinostat, ME-344 or ME-143. Use of these compounds and any other drug candidates may give rise to claims that they infringe the patents or proprietary rights of other parties, existing now and in the future. An adverse claim could subject us to significant liabilities to such other parties and/or require disputed rights to be licensed from such other parties. We cannot be sure that any license required under any such patents or proprietary rights would be made available on terms acceptable to us, if at all. If we do not obtain such licenses, we may encounter delays in product market introductions, or may find that the development, manufacture or sale of products requiring such licenses may be precluded. We have not conducted any searches or made any independent investigations of the existence of any patents or proprietary rights of other parties.

Research and Development

The objective of our research and development program is the generation of data sufficient to achieve regulatory approval of our drug candidates in one or more dosage forms in major markets such as the U.S., to develop commercially attractive attributes, and/or to allow us to enter into a commercial relationship with another party. The data are generated by our pre-clinical studies and clinical trial programs.

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The key aspects of the research and development program are to provide more complete characterization of the following:

Research and development expenses were $6,084,000 for the year ended June 30, 2013 and $4,915,000 for the year ended June 30, 2012. Research and development costs incurred from inception through June 30, 2013 were $50,188,000. We expect research and development expenses to increase during the fiscal year ending June 30, 2014, related primarily to our planned Phase II clinical trials for Pracinostat.

Government Regulation

U.S. Regulatory Requirements

The FDA, and comparable regulatory agencies in other countries, regulate and impose substantial requirements upon the research, development, pre-clinical and clinical testing, labeling, manufacture, quality control, storage, approval, advertising, promotion, marketing, distribution and export of pharmaceutical products including biologics, as well as significant reporting and record-keeping obligations. State governments may also impose obligations in these areas.

In the U.S., pharmaceutical products are regulated by the FDA under the Federal Food, Drug, and Cosmetic Act or FDCA and other laws including in the case of biologics, the Public Health Service Act. We believe, but cannot be certain, that our products will be regulated as drugs by the FDA. The process required by the FDA before drugs may be marketed in the U.S. generally involves the following:

The testing and approval process requires substantial time, effort, and financial resources, and we cannot be certain that any approval will be granted on a timely basis, if at all.

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The results of the pre-clinical studies, together with initial specified manufacturing information, the proposed clinical trial protocol, and information about the participating investigators are submitted to the FDA as part of an IND, which must become effective before we may begin human clinical trials in the U.S. Additionally, an independent IRB must review and approve each study protocol and oversee conduct of the trial. An IND becomes effective 30 days after receipt by the FDA, unless the FDA, within the 30-day period, raises concerns or questions about the conduct of the trials as outlined in the IND and imposes a clinical hold. If the FDA imposes a clinical hold, the IND sponsor must resolve the FDA’s concerns before clinical trials can begin. Pre-clinical tests and studies can take several years to complete, and there is no guarantee that an IND we submit based on such tests and studies will become effective within any specific time period, if at all.

Human clinical trials are typically conducted in three sequential phases that may overlap.

We cannot be certain that we will successfully complete clinical testing of our products within any specific time period, if at all. Furthermore, the FDA, the IRB or we may suspend or terminate clinical trials at any time on various grounds, including a finding that the subjects or patients are being exposed to an unacceptable health risk.

Results of pre-clinical studies and clinical trials, as well as detailed information about the manufacturing process, quality control methods, and product composition, among other things, are submitted to the FDA as part of a NDA seeking approval to market and commercially distribute the product on the basis of a determination that the product is safe and effective for its intended use. Before approving a NDA, the FDA will inspect the facilities at which the product is manufactured and will not approve the product unless cGMP compliance is satisfactory. If applicable regulatory criteria are not satisfied, the FDA may deny the NDA or require additional testing or information. As a condition of approval, the FDA also may require post-marketing testing or surveillance to monitor the product’s safety or efficacy. Even after a NDA is approved, the FDA may impose additional obligations or restrictions (such as labeling changes), or even suspend or withdraw a product approval on the basis of data that arise after the product reaches the market, or if compliance with regulatory standards is not maintained. We cannot be certain that any NDA we submit will be approved by the FDA on a timely basis, if at all. Also, any such approval may limit the indicated uses for which the product may be marketed. Any refusal to approve, delay in approval, suspension or withdrawal of approval, or restrictions on indicated uses could have a material adverse impact on our business prospects.

Each NDA must be accompanied by a user fee, pursuant to the requirements of the Prescription Drug User Fee Act, or PDUFA, and its amendments. According to the FDA’s fee schedule, effective on October 1, 2013 for the fiscal year 2014, the user fee for an application requiring clinical data, such as a NDA, is $2,169,100. The FDA adjusts the PDUFA user fees on an annual basis. PDUFA also imposes an annual product fee for prescription drugs and biologics ($104,060), and an annual establishment fee ($554,600) on facilities used to manufacture prescription drugs and biologics. A written request can be submitted for a waiver for the

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application fee for the first human drug application that is filed by a small business, but there are no waivers for product or establishment fees. We are not at the stage of development with our products where we are subject to these fees, but they are significant expenditures that may be incurred in the future and must be paid at the time of application submissions to FDA.

Satisfaction of FDA requirements typically takes several years. The actual time required varies substantially, based upon the type, complexity, and novelty of the pharmaceutical product, among other things. Government regulation imposes costly and time-consuming requirements and restrictions throughout the product life cycle and may delay product marketing for a considerable period of time, limit product marketing, or prevent marketing altogether. Success in pre-clinical or early stage clinical trials does not ensure success in later stage clinical trials. Data obtained from pre-clinical and clinical activities are not always conclusive and may be susceptible to varying interpretations that could delay, limit, or prevent marketing approval. Even if a product receives marketing approval, the approval is limited to specific clinical indications. Further, even after marketing approval is obtained, the discovery of previously unknown problems with a product may result in restrictions on the product or even complete withdrawal of the product from the market.

After product approval, there are continuing significant regulatory requirements imposed by the FDA, including record-keeping requirements, obligations to report adverse side effects in patients using the products, and restrictions on advertising and promotional activities. Quality control and manufacturing procedures must continue to conform to cGMPs, and the FDA periodically inspects facilities to assess cGMP compliance. Additionally, post-approval changes in ingredient composition, manufacturing processes or facilities, product labeling, or other areas may require submission of a NDA Supplement to the FDA for review and approval. New indications will require additional clinical studies and submission of a NDA Supplement. Failure to comply with FDA regulatory requirements may result in an enforcement action by the FDA, including Warning Letters, product recalls, suspension or revocation of product approval, seizure of product to prevent distribution, impositions of injunctions prohibiting product manufacture or distribution, and civil and criminal penalties. Maintaining compliance is costly and time-consuming. We cannot be certain that we, or our present or future suppliers or third-party manufacturers, will be able to comply with all FDA regulatory requirements, and potential consequences of noncompliance could have a material adverse impact on our business prospects.

The FDA’s policies may change, and additional governmental regulations may be enacted that could delay, limit, or prevent regulatory approval of our products or affect our ability to manufacture, market, or distribute our products after approval. Moreover, increased attention to the containment of healthcare costs in the U.S. and in foreign markets could result in new government regulations that could have a material adverse effect on our business. Our failure to obtain coverage, an adequate level of reimbursement, or acceptable prices for our future products could diminish any revenues we may be able to generate. Our ability to commercialize future products will depend in part on the extent to which coverage and reimbursement for the products will be available from government and health administration authorities, private health insurers, and other third-party payers. European Union member states and U.S. government and other third-party payers increasingly are attempting to contain healthcare costs by consideration of new laws and regulations limiting both coverage and the level of reimbursement for new drugs. We cannot predict the likelihood, nature or extent of adverse governmental regulation that might arise from future legislative or administrative action, either in the U.S. or abroad.

Our activities also may be subject to state laws and regulations that affect our ability to develop and sell our products. We are also subject to numerous federal, state, and local laws relating to such matters as safe working conditions, clinical, laboratory, and manufacturing practices, environmental protection, fire hazard control, and disposal of hazardous or potentially hazardous substances. We may incur significant costs to comply with such laws and regulations now or in the future, and the failure to comply may have a material adverse impact on our business prospects.

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The FDCA includes provisions designed to facilitate the development and expedite the review of drugs and biological products intended for treatment of serious or life-threatening conditions that demonstrate the potential to address unmet medical needs for such conditions. These provisions set forth a procedure for designation of a drug as a “fast track product”. The fast track designation applies to the combination of the product and specific indication for which it is being studied. A product designated as fast track is ordinarily eligible for additional programs for expediting development and review, but products that are not in fast track drug development programs may also be able to take advantage of these programs. These programs include priority review of NDAs and accelerated approval. Drug approval under the accelerated approval regulations may be based on evidence of clinical effect on a surrogate endpoint that is reasonably likely to predict clinical benefit. A post-marketing clinical study will be required to verify clinical benefit, and other restrictions to assure safe use may be imposed. We do not currently have fast track designation for any of our clinical programs. If we should seek such designation for any of our programs, however, we cannot be assured that it will be granted by the FDA.

Under the Drug Price Competition and Patent Term Restoration Act of 1984, a sponsor may obtain marketing exclusivity for a period of time following FDA approval of certain drug applications, regardless of patent status, if the drug is a new chemical entity or if new clinical studies were required to support the marketing application for the drug. This marketing exclusivity prevents a third party from obtaining FDA approval for an identical or nearly identical drug under an Abbreviated New Drug Application or a “505(b)(2) New Drug Application”. The statute also allows a patent owner to obtain an extension of applicable patent terms for a period equal to one-half the period of time elapsed between the filing of an IND and the filing of the corresponding NDA plus the period of time between the filing of the NDA and FDA approval, with a five year maximum patent extension. We cannot be certain that we will be able to take advantage of either the patent term extension or marketing exclusivity provisions of these laws.

The Best Pharmaceuticals for Children Act, or BPCA, signed into law on January 4, 2002, was reauthorized and amended by the FDA Amendments Act of 2007 or FDAAA. The reauthorization of BPCA provides an additional six months of patent protection to NDA applicants that conduct acceptable pediatric studies of new and currently-marketed drug products for which pediatric information would be beneficial, as identified by FDA in a Pediatric Written Request. The Pediatric Research Equity Act, or PREA, signed into law on December 3, 2003, also was reauthorized and amended by FDAAA. The reauthorization of PREA requires that most applications for drugs and biologics include a pediatric assessment (unless waived or deferred) to ensure the drugs’ and biologics’ safety and effectiveness in children. Such pediatric assessment must contain data, gathered using appropriate formulations for each age group for which the assessment is required, that are adequate to assess the safety and effectiveness of the drug or the biological product for the claimed indications in all relevant pediatric subpopulations, and to support dosing and administration for each pediatric subpopulation for which the drug or the biological product is safe and effective. The pediatric assessments can only be deferred provided there is a timeline for the completion of such studies. The FDA may waive (partially or fully) the pediatric assessment requirement for several reasons, including if the applicant can demonstrate that reasonable attempts to produce a pediatric formulation necessary for that age group have failed. The Food and Drug Administration Safety and Innovation Act (FDASIA) signed into law on July 9, 2012, permanently renewed and strengthened BPCA and PREA.

Under the Orphan Drug Act, the FDA may grant orphan drug designation to drugs intended to treat a “rare disease or condition,” which generally is a disease or condition that affects fewer than 200,000 individuals in the U.S. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. If a product which has an orphan drug designation subsequently receives the first FDA approval for the indication for which it has such designation, the product is entitled to orphan exclusivity, i.e., the FDA may not approve any other applications to market the same drug for the same indication for a period of seven years, except in limited circumstances. Our products may not be eligible for orphan drug status or be designated as orphan drugs. Even if designated as orphan drugs, our products may not be approved before other applications or granted orphan drug exclusivity if approved.

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Foreign Regulatory Requirements

Outside the U.S., our ability to market our products will also be contingent upon receiving marketing authorizations from the appropriate regulatory authorities and compliance with applicable post-approval regulatory requirements. Although the specific requirements and restrictions vary from country to country, as a general matter, foreign regulatory systems include risks similar to those associated with FDA regulation, described above.

Under European Union regulatory systems, marketing authorizations may be submitted either under a centralized or a national procedure. Under the centralized procedure, a single application to the European Medicines Agency (EMA) leads to an approval granted by the European Commission which permits the marketing of the product throughout the EU. The centralized procedure is mandatory for certain classes of medicinal products, but optional for others. For example, all medicinal products developed by certain biotechnological means, and those developed for cancer and other specified diseases and disorders, must be authorized via the centralized procedure. We assume that the centralized procedure will apply to our products that are developed by means of a biotechnology process or are intended for treatment of cancer. The national procedure is used for products that are not required to be authorized by the centralized procedure. Under the national procedure, an application for a marketing authorization is submitted to the competent authority of one member state of the EU. The holders of a national marketing authorization may submit further applications to the competent authorities of the remaining member states via either the decentralized or mutual recognition procedure. The decentralized procedure enables applicants to submit an identical application to the competent authorities of all member states where approval is sought at the same time as the first application, while under the mutual recognition procedure, products are authorized initially in one member state, and other member states where approval is sought are then requested to recognize the original authorization based upon an assessment report prepared by the original authorizing competent authority. Both the decentralized and mutual recognition procedures should take no longer than 90 days, but if one member state makes an objection, which under the legislation can only be based on a possible risk to human health, the application will be automatically referred to the Committee for Medicinal Products for Human Use (CHMP) of the EMA. If a referral for arbitration is made, the procedure is suspended. However, member states that have already approved the application may, at the request of the applicant, authorize the product in question without waiting for the result of the arbitration. Such authorizations will be without prejudice to the outcome of the arbitration. For all other concerned member states, the opinion of the CHMP, which is binding, could support or reject the objection or alternatively could reach a compromise position acceptable to all EU countries concerned. The arbitration procedure may take an additional year before a final decision is reached and may require the delivery of additional data.

As with FDA approval, we may not be able to secure regulatory approvals in Europe in a timely manner, if at all. Additionally, as in the U.S., post-approval regulatory requirements, such as those regarding product manufacture, marketing, or distribution, would apply to any product that is approved in Europe, and failure to comply with such obligations could have a material adverse effect on our ability to successfully commercialize any product.

The conduct of clinical trials in the European Union is governed by the European Clinical Trials Directive (2001/20/EC), which was implemented in May 2004. This Directive governs how regulatory bodies in member states control clinical trials. No clinical trial may be started without a clinical trial authorization granted by the national competent authority and favorable ethics approval. New legislation to revise and replace the European Clinical Trials Directive is currently proposed by the European Commission and is under consideration by European Union institutions.

Accordingly, there is a marked degree of change and uncertainty both in the regulation of clinical trials and in respect of marketing authorizations which face us for our products in Europe.

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Manufacturing

We do not have the facilities or capabilities to commercially manufacture any of our products and product candidates. We are and expect to continue to be dependent on contract manufacturers for supplying our existing and future product candidates for clinical trials and commercial scale manufacturing of our product candidates in accordance with regulatory requirements, including current Good Manufacturing Practices. Contract manufacturers may utilize their own technology, technology developed by us, or technology acquired or licensed from third parties. FDA approval of the manufacturing procedures and the site will be required prior to commercial distribution.

Employees

As of June 30, 2013, we had thirteen employees, four of whom hold a Ph.D. or M.D. degree. Other personnel resources are used from time to time as consultants or third party service organizations on an as-needed basis. All members of our senior management team have prior experience with pharmaceutical, biotechnology or medical product companies. We believe that we have been successful in attracting skilled and experienced personnel, but there can be no assurance that we will be able to attract and retain the individuals needed. None of our employees are represented by a collective bargaining agreement, nor have we experienced work stoppages. We believe that our relations with our employees are good.

Available Information

Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed with or furnished to the Securities and Exchange Commission pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, are available free of charge through our website at www.meipharma.com as soon as reasonably practicable after they are electronically filed with, or furnished to, the Securities and Exchange Commission.

Item 1A. Risk Factors

Investment in our securities involves a high degree of risk. You should consider carefully the risks described below, together with other information in this Annual Report on Form 10-K and our other public filings, before making investment decisions regarding our securities. If any of the following events actually occur, our business, operating results, prospects or financial condition could be materially and adversely affected. This could cause the trading price of our common stock to decline and you may lose all or part of your investment. Moreover, the risks described below are not the only ones that we face. Additional risks not presently known to us or that we currently deem immaterial may also affect our business, operating results, prospects or financial condition.

Risks Related to Our Business

We will need substantial additional funds to progress the clinical trial program for our drug candidates Pracinostat, ME-344 and ME-143 and to develop new compounds. The actual amount of funds we will need will be determined by a number of factors, some of which are beyond our control.

We will need substantial additional funds to progress the clinical trial program for our drug candidates Pracinostat, ME-344 and ME-143 and to develop any additional compounds. The factors which will determine the actual amount of funds that we will need to progress the clinical trial programs for Pracinostat, ME-344 and ME-143 may include the following:

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We have been opportunistic in our efforts to obtain cash, and we expect to continue to evaluate various funding alternatives from time to time. If we obtain additional funding, it may adversely affect the market price of our common stock. If we are unable to obtain additional funds on favorable terms or at all, we may be required to cease or reduce our operations. We may sell additional shares of common stock, and securities exercisable for or convertible into shares of our common stock, to satisfy our capital and operating needs; however, such transactions will be subject to market conditions and there can be no assurance any such transactions will be completed.

The number of shares of our common stock outstanding has increased substantially as a result of our December 2012 private placement and our April 2013 underwritten registered offering, and some of the purchasers in the private placement beneficially own significant amounts of our common stock.

In December 2012, we completed the private placement of an aggregate of (i) 9,166,665 shares of our common stock and (ii) warrants to purchase an aggregate of 6,416,665 shares of our common stock. In April 2013, we completed an underwritten registered offering of 2,030,000 shares of our common stock. Some of the purchasers in the private placement beneficially own significant amounts of our common stock and will have a corresponding influence over the outcome of any stockholder vote, including the election of directors and the approval of mergers or other business combination transactions.

Negative U.S. and global economic conditions may pose challenges to our business strategy, which relies on funding from the financial markets or collaborators.

Negative conditions in the U.S. or global economy, including financial markets, may adversely affect our business and the business of current and prospective vendors, licensees and collaborators, and others with whom we do or may conduct business. The duration and severity of these conditions is uncertain. If negative economic conditions occur, we may be unable to secure funding to sustain our operations or to find suitable collaborators to advance our internal programs, even if we achieve positive results from our research and development efforts.

We have a limited operating history and are likely to incur operating losses for the foreseeable future.

You should consider our prospects in light of the risks and difficulties frequently encountered by early stage and developmental companies. We were incorporated in December 2000, and have been in operation since May 2002. We have incurred net losses of $96,297,000 from our inception through June 30, 2013, including net losses of $11,186,000 and $7,523,000 for the years ended June 30, 2013 and 2012, respectively. We anticipate that we will incur operating losses and negative operating cash flow for the foreseeable future. We have not yet commercialized any drug candidates and cannot be sure that we will ever be able to do so, or that we may ever become profitable.

Our stockholders may not realize a benefit from the purchase of intellectual property commensurate with the associated ownership dilution experienced.

In August 2012, we completed the acquisition of certain assets and intellectual property, including those related to Pracinostat, from S*Bio. Additionally, in May 2011, we completed the acquisition (the “Isoflavone Transaction”) of certain assets used in or generated under or in connection with the discovery, development, manufacture and marketing of intellectual property and products based on the field of isoflavonoid technology and on compounds known as isoflavones, including those related to the drug candidates ME-344 and ME-143 (the “Isoflavone-related Assets”), from Novogen.

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If we are unable to realize the expected strategic and financial benefits from the purchase of intellectual property, our stockholders may experience substantial dilution of their ownership interest as a result of the issuance of shares of common stock to Novogen to acquire the Isoflavone-related Assets, and as a result of the issuance of 195,756 shares of common stock to S*Bio to acquire certain assets and intellectual property, including those related to Pracinostat, without receiving any commensurate benefit. In the asset purchase agreement relating to the acquisition of certain assets and intellectual property from S*Bio, S*Bio made certain representations and warranties regarding its intellectual property rights to such assets; however, its indemnification obligations with respect to such representations and warranties are limited. Similarly, upon consummation of the Isoflavone Transaction, we issued to Novogen 1,000 shares of our Series A Convertible Preferred Stock which were subsequently converted into an aggregate of 804,500 shares of our common stock in November 2012. Although in the Isoflavone Asset Purchase Agreement Novogen made certain representations and warranties regarding its intellectual property rights in respect of the Isoflavone-related Assets, Novogen’s indemnification obligations, which were limited and payable solely by the forfeiture of our securities issued as consideration in the Isoflavone Transaction, expired on June 30, 2011.

Accordingly, we do not expect to be adequately compensated, if at all, for the loss of any such intellectual property rights acquired in the acquisition from S*Bio or in the Isoflavone Transaction.

The results of pre-clinical studies and completed clinical trials are not necessarily predictive of future results, and our current drug candidates may not have favorable results in later studies or trials.

Pre-clinical studies and Phase I and Phase II clinical trials are an expensive and uncertain process that may take years to complete. Pre-clinical studies and Phase I and Phase II clinical trials are not primarily designed to test the efficacy of a drug candidate, but rather to test safety, to study pharmacokinetics and pharmacodynamics, and to understand the drug candidate’s side effects at various doses and schedules. Favorable results in early studies or trials may not be repeated in later studies or trials, including ongoing pre-clinical studies and large-scale Phase III clinical trials, and our drug candidates in later-stage trials may fail to show desired safety and efficacy despite having progressed through earlier-stage trials. Unfavorable results from ongoing pre-clinical studies or clinical trials could result in delays, modifications or abandonment of ongoing or future clinical trials, or abandonment of a clinical program. Pre-clinical and clinical results are frequently susceptible to varying interpretations that may delay, limit or prevent regulatory approvals or commercialization. Negative or inconclusive results or adverse medical events during a clinical trial could cause a clinical trial to be delayed, repeated or terminated, or a clinical program to be abandoned.

Final approval by regulatory authorities of our drug candidates for commercial use may be delayed, limited or prevented, any of which would adversely affect our ability to generate operating revenues.

We will not generate any operating revenue until we successfully license or commercialize one of our drug candidates. Currently, we have drug candidates at different stages of development, and each will need to successfully complete a number of studies and obtain regulatory approval before potential commercialization.

The preclinical and clinical development, manufacturing, labeling, packaging, storage, recordkeeping, export, marketing and distribution, and other possible activities relating to our drug candidates are subject to extensive regulation by the FDA and other regulatory agencies. Failure to comply with applicable regulatory requirements may, either before or after product approval, subject us to administrative or judicially imposed sanctions that may negatively impact the approval of one or more of our drug candidates or otherwise negatively impact our business.

Neither collaborators nor we are permitted to market a drug candidate in the United States until the particular drug candidate is approved for marketing by the FDA. Specific preclinical data, chemistry, manufacturing and controls data, a proposed clinical trial protocol and other information must be submitted to the FDA as part of an investigational new drug, or IND, application, and clinical trials may commence only after the

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IND application becomes effective. To market a new drug in the United States, we must submit to the FDA and obtain FDA approval of a NDA. A NDA must be supported by extensive clinical and preclinical data, as well as extensive information regarding chemistry, manufacturing and controls to demonstrate the safety and effectiveness of the drug candidate.

Obtaining approval of an NDA can be a lengthy, expensive and uncertain process. Regulatory approval of an NDA is not guaranteed. The number and types of preclinical studies and clinical trials that will be required for FDA approval varies depending on the drug candidate, the disease or condition that the drug candidate is designed to target and the regulations applicable to any particular drug candidate. Despite the time and expense exerted in preclinical and clinical studies, failure can occur at any stage, and we could encounter problems that cause us to abandon clinical trials or to repeat or perform additional preclinical studies and clinical trials. The FDA can delay, limit or deny approval of a drug candidate for many reasons, including:

Our preclinical and clinical data, other information and procedures relating to a drug candidate may not be sufficient to support approval by the FDA or any other U.S. or foreign regulatory authority, or regulatory interpretation of these data and procedures may be unfavorable. Our business and reputation may be harmed by any failure or significant delay in receiving regulatory approval for the sale of any drugs resulting from our drug candidates. As a result, we cannot predict when or whether regulatory approval will be obtained for any drug we develop.

Additionally, any of the following factors may serve to delay, limit or prevent the final approval by regulatory authorities of our drug candidates for commercial use:

The successful development of any of these drug candidates is uncertain and, accordingly, we may never commercialize any of these drug candidates or generate revenue.

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Even if we receive regulatory approval to commercialize our drug candidates, our ability to generate revenues from any resulting products will be subject to a variety of risks, many of which are out of our control.

Even if our drug candidates obtain regulatory approval, resulting products may not gain market acceptance among physicians, patients, healthcare payers or the medical community. We believe that the degree of market acceptance and our ability to generate revenues from such products will depend on a number of factors, including:

If any of our drugs are approved and fail to achieve market acceptance, we may not be able to generate significant revenue to achieve or sustain profitability.

We may not be able to establish the contractual arrangements necessary to develop, market and distribute our product candidates.

A key part of our business plan is to establish contractual relationships with third parties to package, market and distribute our product candidates. There is no assurance that we will be able to negotiate commercially acceptable licensing or other agreements for the future exploitation of our drug product candidates, including continued clinical development, manufacture or marketing. If we are unable to successfully contract for these services, or if arrangements for these services are terminated, we may have to delay our commercialization program which will adversely affect our ability to generate operating revenues.

Our commercial opportunity will be reduced or eliminated if competitors develop and market products that are more effective, have fewer side effects or are less expensive than our drug candidates.

The development of drug candidates is highly competitive. A number of other companies have products or drug candidates that have either been approved or are in various stages of pre-clinical or clinical development that are intended for the same therapeutic indications for which our drug candidates are being developed. Some of these potential competing drugs are further advanced in development than our drug candidates and may be commercialized sooner. Even if we are successful in developing effective drugs, our compounds may not compete successfully with products produced by our competitors.

Our competitors include pharmaceutical companies and biotechnology companies, as well as universities and public and private research institutions. In addition, companies active in different but related fields represent substantial competition for us. Many of our competitors developing oncology drugs have significantly greater capital resources, larger research and development staffs and facilities and greater experience in drug development, regulation, manufacturing and marketing than we do. These organizations also compete with us and our service providers, to recruit qualified personnel, and with us to attract partners for joint ventures and to license technologies that are competitive with us. As a result, our competitors may be able to more easily develop technologies and products that would render our technologies or our drug candidates obsolete or non-competitive.

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We rely on third parties to conduct our clinical trials and many of our pre-clinical studies. If those parties do not successfully carry out their contractual duties or meet expected deadlines, our drug candidates may not advance in a timely manner or at all.

In the course of our discovery, pre-clinical testing and clinical trials, we rely on third parties, including laboratories, investigators, clinical contract research organizations, or CROs, and manufacturers, to perform critical services for us. For example, we rely on third parties to conduct our clinical trials and many of our pre-clinical studies. CROs are responsible for many aspects of the trials, including finding and enrolling subjects for testing and administering the trials. Although we rely on these third parties to conduct our clinical trials, we are responsible for ensuring that each of our clinical trials is conducted in accordance with its investigational plan and protocol. Moreover, the FDA and foreign regulatory authorities require us to comply with regulations and standards, commonly referred to as good clinical practices, or GCPs, for conducting, monitoring, recording, and reporting the results of clinical trials to ensure that the data and results are scientifically credible and accurate, and that the trial subjects are adequately informed of the potential risks of participating in clinical trials. Our reliance on third parties does not relieve us of these responsibilities and requirements. These third parties may not be available when we need them or, if they are available, may not comply with all regulatory and contractual requirements or may not otherwise perform their services in a timely or acceptable manner, and we may need to enter into new arrangements with alternative third parties and our clinical trials may be extended, delayed or terminated. These independent third parties may also have relationships with other commercial entities, some of which may compete with us. In addition, if such third parties fail to perform their obligations in compliance with our clinical trial protocols or GCPs, our clinical trials may not meet regulatory requirements or may need to be repeated. As a result of our dependence on third parties, we may face delays or failures outside of our direct control. These risks also apply to the development activities of collaborators, and we do not control their research and development, clinical trial or regulatory activities.

We have no direct control over the cost of manufacturing our drug candidates. Increases in the cost of manufacturing our drug candidates would increase our costs of conducting clinical trials and could adversely affect our future profitability.

We do not intend to manufacture our drug product candidates ourselves, and we will rely on third parties for our drug supplies both for clinical trials and for commercial quantities in the future. We have taken the strategic decision not to manufacture active pharmaceutical ingredients (“API”) for our drug candidates, as these can be more economically supplied by third parties with particular expertise in this area. We have identified contract facilities that are registered with the FDA, have a track record of large scale API manufacture, and have already invested in capital and equipment. We have no direct control over the cost of manufacturing our product candidates. If the cost of manufacturing increases, or if the cost of the materials used increases, these costs will be passed on to us, making the cost of conducting clinical trials more expensive. Increases in manufacturing costs could adversely affect our future profitability if we are unable to pass all of the increased costs along to our customers. We also rely on the contract manufacturers to comply with FDA regulatory requirements for good manufacturing practices.

We rely on acquisitions or licenses from third parties to expand our pipeline of drug candidates.

We are not presently engaged in drug discovery activities. In order to expand our pipeline of drug candidates for future development, we may need to purchase or in-license any such drug candidates. However, we may not be able to purchase or in-license future drug candidates from third parties on favorable terms, or at all.

We face a risk of product liability claims and may not be able to obtain adequate insurance.

Our business exposes it to the risk of product liability claims. This risk is inherent in the manufacturing, testing and marketing of human therapeutic products. We have product liability insurance

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coverage of $5 million. The coverage is subject to deductibles and coverage limitations. We may not be able to obtain or maintain adequate protection against potential liabilities, or claims may exceed our insurance limits. If we cannot or do not sufficiently insure against potential product liability claims, we may be exposed to significant liabilities, which may materially and adversely affect our business development and commercialization efforts.

Our efforts will be seriously jeopardized if we are unable to retain and attract key employees.

Our success depends on the continued contributions of our principal management, development and scientific personnel. We face competition for such personnel, and we believe that risks and uncertainties related to our business, including the timing and risk associated with research and development, our available and anticipated cash resources, and the volatility of our stock price, may impact our ability to hire and retain key and other personnel. The loss of services of our Chief Executive Officer or other key employees could adversely impact our operations and ability to generate or raise additional capital.

Laws, rules and regulations relating to public companies may be costly and impact our ability to attract and retain directors and executive officers.

Laws and regulations affecting public companies, including rules adopted by the SEC and by Nasdaq, may result in increased costs to us. These laws, rules and regulations could make it more difficult or costly for us to obtain certain types of insurance, including director and officer liability insurance, and we may be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. The impact of these events could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, on our board committees or as executive officers. We cannot estimate accurately the amount or timing of additional costs we may incur to respond to these laws, rules and regulations.

Risks Relating to Our Intellectual Property

Our commercial success is dependent, in part, on obtaining and maintaining patent protection and preserving trade secrets, which cannot be guaranteed.

Patent protection and trade secret protection are important to our business and our future will depend, in part on our ability to maintain trade secret protection, obtain patents and operate without infringing the proprietary rights of others both in the United States and abroad. Litigation or other legal proceedings may be necessary to defend against claims of infringement, to enforce our patents or to protect our trade secrets. Such litigation could result in substantial costs and diversion of our management’s attention.

The patent positions of pharmaceutical and biotechnology companies can be highly uncertain and involve complex legal and factual questions. In August 2012, we acquired patents and patent applications related to Pracinostat from S*Bio. Additionally, prior to the Isoflavone Transaction, Novogen had applied for patents in a number of countries with respect to the use of their isoflavone compounds, including ME-344 and ME-143, for the treatment, prevention or cure of cancer and methods of production of Phenoxodiol. We acquired both issued patents and pending patent applications from Novogen in relation to these technologies, which we previously licensed from Novogen. The patent applications may not proceed to grant or may be amended to reduce the scope of protection of any patent granted. The applications and patents may also be opposed or challenged by third parties. Our commercial success will depend, in part, on our ability to obtain and maintain effective patent protection for our compounds and their use in treating, preventing, or curing cancer, and to successfully defend patent rights in those technologies against third-party challenges. As patent applications in the United States are maintained in secrecy until published or issued and as publication of discoveries in the scientific or patent literature often lag behind the actual discoveries, we cannot be certain that S*Bio or Novogen were the first to make the inventions covered by their pending patent applications or issued patents that we acquired or that they were the first to file patent applications for such inventions. Additionally, the breadth of claims allowed in

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biotechnology and pharmaceutical patents or their enforceability cannot be predicted. We cannot be sure that, should any patents issue, we will be provided with adequate protection against potentially competitive products. Furthermore, we cannot be sure that should patents issue, they will be of commercial value to us, or that private parties, including competitors, will not successfully challenge our patents or circumvent our patent position in the United States or abroad.

Claims by other companies that we infringe on their proprietary technology may result in liability for damages or stop our development and commercialization efforts.

The pharmaceutical industry is highly competitive and patents have been applied for by, and issued to, other parties relating to products competitive with the compounds that we have acquired. Therefore, Pracinostat, ME-344 and ME-143 and any other drug candidates may give rise to claims that they infringe the patents or proprietary rights of other parties existing now and in the future.

Furthermore, to the extent that we or our consultants or research collaborators use intellectual property owned by others in work performed for us, disputes may also arise as to the rights in such intellectual property or in resulting know-how and inventions. An adverse claim could subject us to significant liabilities to such other parties and/or require disputed rights to be licensed from such other parties.

We have contracted formulation development and manufacturing process development work for our product candidates. This process has identified a number of excipients, or additives to improve drug delivery, which may be used in the formulations. Excipients, among other things, perform the function of a carrier of the active drug ingredient. Some of these identified excipients or carriers may be included in third party patents in some countries. We intend to seek a license if we decide to use a patented excipient in the marketed product or we may choose one of those excipients that does not have a license requirement.

We cannot be sure that any license required under any such patents or proprietary rights would be made available on terms acceptable to us, if at all. If we do not obtain such licenses, we may encounter delays in product market introductions, or may find that the development, manufacture or sale of products requiring such licenses may be precluded. We have not conducted any searches or made any independent investigations of the existence of any patents or proprietary rights of other parties.

We may be subject to substantial costs stemming from our defense against third-party intellectual property infringement claims.

Third parties may assert that we are using their proprietary information without authorization. Third parties may also have or obtain patents and may claim that technologies licensed to or used by us infringe their patents. If we are required to defend patent infringement actions brought by third parties, or if we sue to protect our own patent rights, we may be required to pay substantial litigation costs and managerial attention may be diverted from business operations even if the outcome is not adverse to us. In addition, any legal action that seeks damages or an injunction to stop us from carrying on our commercial activities relating to the affected technologies could subject us to monetary liability and require us or any third party licensors to obtain a license to continue to use the affected technologies. We cannot predict whether we would prevail in any of these types of actions or that any required license would be made available on commercially acceptable terms or at all.

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Risks Related to Securities Markets and Investment in Our Stock

The trading price of the shares of our common stock has been and may continue to be highly volatile and could decline in value and we may incur significant costs from class action litigation.

The trading price of our common stock could be highly volatile in response to various factors, many of which are beyond our control, including:

Equity markets in general, and the market for biotechnology and life sciences companies in particular, have experienced substantial price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of companies traded in those markets. In addition, changes in economic conditions in the U.S., Europe or globally, particularly in the context of current global events, could impact upon our ability to grow profitably. Adverse economic changes are outside our control and may result in material adverse impacts on our business or our results of operations. These broad market and industry factors may materially affect the market price of shares of our common stock, regardless of our development and operating performance. In the past, following periods of volatility in the market price of a company’s securities, securities class-action litigation has often been instituted against that company. Such litigation, if instituted against us, could cause us to incur substantial costs and divert management’s attention and resources.

Future sales of our common stock, including common stock issued upon exercise of outstanding warrants or options, may depress the market price of our common stock and cause stockholders to experience dilution.

The market price of our common stock could decline as a result of sales of substantial amounts of our common stock in the public market, including upon exercise of outstanding warrants or stock options and any subsequent sales of such shares. As of June 30, 2013, we had outstanding (i) warrants issued in our December 2012 private placement exercisable to purchase 4,526,361 shares of Common Stock at an exercise price of $3.12 per share, which expire on December 18, 2017; (ii) warrants issued in our May 2012 rights offering exercisable to purchase 319,150 shares of Common Stock at an exercise price of $7.14, which expire on May 10, 2017; (iii) Series A warrants issued in our May 2011 private placement exercisable to purchase 215,721 shares of Common Stock at an exercise price of $6.00, which expire on May 11, 2016; and (iv) other outstanding warrants exercisable to purchase 768 shares of our Common Stock at an exercise price of $130.20 per share, which expired unexercised in July 2013. We may seek additional capital through one or more additional equity transactions in the future; however, such transactions will be subject to market conditions and there can be no

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assurance any such transactions will be completed. If we sell shares in the future, the prices at which we sell these future shares will vary, and these variations may be significant. Purchasers of the shares will experience significant dilution if we sell these future shares at prices significantly below the price at which previous shareholders invested.

Because we do not intend to pay, and have not paid, any cash dividends on our shares of common stock, our stockholders will not be able to receive a return on their shares unless the value of our common stock appreciates and they sell their shares.

We have never paid or declared any cash dividends on our common stock, and we intend to retain any future earnings to finance the development and expansion of our business. We do not anticipate paying any cash dividends on our common stock in the foreseeable future. Therefore, our stockholders will not be able to receive a return on their investment unless the value of our common stock appreciates and they sell their shares.

We will have broad discretion over the use of the net proceeds from any exercise of outstanding warrants and options.

We will have broad discretion to use the net proceeds to us upon any exercise of outstanding warrants and options, and investors in our stock will be relying on the judgment of our board of directors and management regarding the application of these proceeds. Although we expect to use a substantial portion of the net proceeds from any exercise of the warrants and options for general corporate purposes and progression of our clinical trial programs, we have not allocated these net proceeds for specific purposes.

We are authorized to issue blank check preferred stock, which could adversely affect the holders of our common stock.

Our restated certificate of incorporation allows us to issue blank check preferred stock with rights potentially senior to those of our common stock without any further vote or action by the holders of our common stock. The issuance of a class of preferred stock could decrease the amount of earnings and assets available for distribution to the holders of our common stock or could adversely affect the rights and powers, including voting rights, of such holders. In certain circumstances, such issuance could have the effect of decreasing the market price of our shares, or making a change in control of the Company more difficult.

Our executive officers and directors may sell shares of their stock, and these sales could adversely affect our stock price.

Sales of our stock by our executive officers and directors, or the perception that such sales may occur, could adversely affect the market price of our stock. Our executive officers and directors may sell stock in the future, either as part, or outside, of trading plans under Securities and Exchange Commission, or SEC, Rule 10b5-1.

None.

We have leased approximately 6,200 square feet of office space, located at 11975 El Camino Real, Suite 101, San Diego, California 92130. The location houses the Company’s executive and administrative offices. The lease commenced in July 2010 and expires in June 2015. Monthly rental rates range from $17,014 to $18,252 over the remaining lease term, plus a pro rata share of certain building expenses. We believe these facilities will adequately meet our office needs for the foreseeable future.

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None.

Item 4. Mine Safety Disclosures

Not applicable.

PART II

During the fiscal years ended June 30, 2013 and 2012, our common stock was listed on the Nasdaq Capital Market. On July 2, 2012, in conjunction with the effectiveness of our corporate name change to MEI Pharma, our common stock commenced trading under the symbol “MEIP” previously our common stock had traded under the symbol “MSHL”. The following table sets forth, for the periods indicated, the high and low sale prices of our common stock for each quarterly period within the two most recent fiscal years.

Holders

As of September 12, 2013, there were 17,116,662 shares of our common stock outstanding and 3,158 holders of record of our common stock. This number was derived from our shareholder records and does not include beneficial owners of our common stock whose shares are held in the name of various dealers, clearing agencies, banks, brokers and other fiduciaries.

For a discussion of outstanding warrants and other securities exercisable for or convertible into shares of our common stock, please see Note 4 under Item 8 in this Annual Report on Form 10-K.

Dividends

We have never declared or paid any cash dividends on our common stock and do not anticipate paying any cash dividends in the foreseeable future. We currently intend to retain all available funds and future earnings, if any, to support operations and finance the growth and development of our business. Any future determination related to our dividend policy will be made at the discretion of our board of directors.

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Issuer Repurchases of Equity Securities

None.

We are a smaller reporting company as defined by Rule 12b-2 of the Exchange Act and are not required to provide the information under this item.

The following discussion and analysis should be read in conjunction with “Item 8. Financial Statements and Supplementary Data” included below in this Annual Report on Form 10-K. Operating results are not necessarily indicative of results that may occur in future periods.

This discussion and analysis contains forward-looking statements that involve a number of risks, uncertainties and assumptions. Actual results may differ materially from those anticipated in the forward-looking statements as a result of many factors including, but not limited to, those set forth under “Cautionary Statement About Forward-Looking Statements” and “Risk Factors” in Item 1A. included above in this Annual Report on Form 10-K. All forward-looking statements included in this Annual Report are based on the information available to us as of the time we file this Annual Report, and except as required by law, we undertake no obligation to update publicly or revise any forward-looking statements.

Overview and Recent Developments

Our business purpose is the development of drugs for the treatment of cancer. We are principally focused on the clinical development of our lead drug candidate, Pracinostat, as well as the advancement of our isoflavone-based drug candidates, ME-344 and ME-143. We acquired Pracinostat in August 2012 from S*Bio, a privately held biotechnology company, in exchange for 195,756 shares of common stock, valued at $500,000, and the assumption of specified liabilities. The agreement with S*Bio also provides for potential success-based clinical, regulatory and sales milestone payments of up to $75.2 million, as well as low single-digit contingent earn-out payments based on net sales. Our clinical development pipeline also includes two isoflavone-based drug candidates, ME-344 and ME-143. We acquired ME-344 and ME-143 in May 2011 from Novogen and Novogen Research Pty Limited , a wholly-owned subsidiary of Novogen, in exchange for 1,000 shares of our Series A Convertible Preferred Stock, which were subsequently converted into 804,500 shares of common stock in November 2012, and the assumption of specified potential liabilities related to these assets.

We have incurred net losses of $96.3 million since our inception in December 2000 through June 30, 2013, and may incur substantial net losses in the future as we advance our research and development programs. We have not generated any revenues from operations since inception and we expect to incur operating losses and generate negative cash flows from operations for the foreseeable future. We may need additional financing to fund our operations in the future, including the continued development of our lead drug candidates.

Clinical Developments

In June 2013 we initiated a blinded, placebo-controlled Phase II clinical trial of Pracinostat in combination with Vidaza in patients with previously untreated intermediate-2 or high-risk MDS, the first in a series of Phase II studies we have planned for Pracinostat. The multicenter trial is expected to enroll 100 patients with a one-to-one randomization. Completion of enrollment is anticipated by June 2014 with topline data expected in December 2014. The primary endpoint of the study is complete remission (CR). Secondary endpoints include overall response rate (CR+CRi+PR), hematologic improvement, duration of response, progression-free survival, rate of leukemic transformation, overall survival and safety. In addition, we are preparing for two open label Phase II trials of Pracinostat: one in combination with Vidaza in elderly patients with AML who are not

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suited for induction therapy, expected to initiate in the fall of 2013, and the other in combination with Vidaza or Dacogen^® (decitabine) in patients with hypomethylating agent refractory MDS soon thereafter.

In April 2012 we initiated a first-in-human, dose-escalation study of intravenous ME-344 in patients with solid refractory tumors. The dose-escalation trial is evaluating the safety and tolerability of ME-344. In addition, the single-agent trial is designed to characterize the pharmacokinetic profile of intravenous ME-344 and describe any preliminary clinical anti-tumor activity observed. As of September 2013, a number of patients are still being followed in the trial, with disease control ranging from five months to one year. Results from the trial are expected during the fourth quarter of calendar year 2013.

Equity Transactions

April 2013 Common Stock Offering

On April 10, 2013, we completed an underwritten registered offering of 2,030,000 shares of our common stock at a price per share of $7.50 pursuant to a “shelf” registration statement previously filed and declared effective by the Securities and Exchange Commission for gross proceeds of $15,225,000, before underwriters’ discount and expenses. We plan to use the net proceeds of the offering, together with other available funds, to primarily progress the clinical development program for our lead drug candidate, Pracinostat, and for other general corporate purposes.

December 2012 Private Placement

On December 18, 2012, we completed the sale (the “December 2012 private placement”) of 9,166,665 shares (the “Initial Shares”) of common stock and warrants (the “Warrants”) to purchase an additional 6,416,665 shares (the “Warrant Shares” and, together with the Initial Shares, the “Shares”) of common stock for an aggregate offering price of $27.5 million, pursuant to the terms a Securities Purchase Agreement, dated November 4, 2012, between us and certain accredited investors identified therein. As of the date of the closing of the December 2012 private placement, two of the investors, Vivo Ventures Fund VII, L.P. (“Vivo”) and New Leaf Ventures II, L.P. (“New Leaf”) each owned in excess of 20% of our outstanding common stock.

Reverse Stock Split

On December 18, 2012, we filed a Certificate of Amendment to our Restated Certificate of Incorporation in order to effect a 1-for-6 reverse stock split (the “2012 Reverse Stock Split”) of our common stock effective on December 18, 2012. As a result of the 2012 Reverse Stock Split, every six shares of our issued and outstanding common stock were combined into one share of common stock. The 2012 Reverse Stock Split did not change the number of authorized shares of common stock. All financial data and share information in this Annual Report on Form 10-K has been presented on an as-adjusted basis to give effect to the 2012 Reverse Stock Split.

S*Bio Asset Purchase

On August 7, 2012, we entered into a definitive asset purchase agreement with S*Bio, pursuant to which we agreed to acquire certain assets comprised of intellectual property and technology including rights to Pracinostat, in exchange for $500,000 of common stock. On August 22, 2012, we completed the asset purchase and issued 195,756 shares of common stock to S*Bio. We also agreed to make certain milestone payments to S*Bio based on the achievement of certain clinical, regulatory and net sales-based milestones, as well as to make certain contingent earnout payments to S*Bio. Milestone payments will be made to S*Bio up to an aggregate amount of $75.2 million if certain U.S., E.U. and Japanese regulatory approvals are obtained and if certain net sales thresholds are met in North America, the E.U. and Japan. We will pay $500,000 of the first milestone payment in shares of common stock. S*Bio will be entitled to receive certain contingent earnout payments based on certain worldwide net sales thresholds on a product-by-product and country-by-country basis.

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Rights Offering

In May 2012, we completed a rights offering (“Rights Offering”) pursuant to which we distributed, at no charge, to holders of record as of March 30, 2012, subscription rights (the “Rights”) to purchase up to 17,129,361 units for an aggregate purchase price of up to $7.6 million. The subscription period for the Rights Offering expired on May 11, 2012. Each unit consisted of 0.0833 shares of common stock and a warrant representing the right to purchase 0.04167 shares of our common stock at an exercise price of $7.14 per share. The exercise of one Right entitled holders to purchase one unit at a subscription price of $0.445 per unit, which represented the subscription price of $5.34 per whole share. Eligible participants in the Rights Offering exercised Rights to purchase an aggregate of 11,660,606 units; accordingly, we issued 971,700 shares of common stock and warrants to purchase an additional 485,857 shares of our common stock. The warrants are exercisable for a five-year period beginning on May 11, 2012. We received net proceeds of $4.8 million associated with the Rights Offering.

Waiver Agreement

On December 5, 2012, the Company entered into an agreement (the “Waiver Agreement”) with Novogen and Novogen Research Pty Limited, a wholly-owned subsidiary of Novogen (together, the “Novogen Parties”), Graham Kelly, an individual, and Andrew Heaton, an individual, pursuant to which the Company granted a limited waiver with respect to certain non-compete provisions contained in the Asset Purchase Agreement dated as of December 20, 2010, between the Company and the Novogen Parties. In consideration of the Company’s grant of the limited waiver, upon the execution of the Waiver Agreement, Novogen surrendered to the Company for cancellation warrants held by Novogen for the purchase of 166,666 shares of Common Stock.

Securities Subscription Agreements – Novogen

In September 2011, we entered into a Securities Subscription Agreement with Novogen, pursuant to which we sold to Novogen 222,222 shares of our common stock, at a purchase price of $9.00 per share, for proceeds of $2,000,000. The offering closed on September 29, 2011. In December 2011, we entered into a Securities Subscription Agreement with Novogen, pursuant to which we sold to Novogen 323,625 shares of our common stock, at a purchase price of $6.18 per share, for proceeds of $2,000,000. The offering closed on December 29, 2011.

At Market Issuance Sales Agreement

During February and March 2011, we issued 9,200 shares of common stock resulting in net cash proceeds of $45,000, pursuant to an At Market Issuance Sales Agreement with McNicoll, Lewis & Vlak LLC (“MLV”). Additionally, during March 2011, as part of a contemplated series of transactions with Ironridge Global Biopharma, a division of Ironridge Global IV, Ltd., a British Virgin Islands business company (“Ironridge”), we (i) issued 107,391 shares of common stock to Ironridge for a fully secured interest-bearing note receivable of $1,001,700, (ii) issued 742 shares of Series B preferred stock to Ironridge for net cash proceeds of $665,000, and (iii) redeemed the 742 shares of Series B preferred stock and cancelled the note receivable pursuant to a Stock Purchase Agreement with Ironridge.

May 2011 Private Placement

On May 16, 2011, we entered into an Amended and Restated Securities Purchase Agreement (the “Amended Securities Purchase Agreement”) with certain accredited investors pursuant to which we agreed to issue and sell to the investors certain shares of our common stock, and warrants to purchase additional shares of common stock. Pursuant to the Amended Securities Purchase Agreement, in May 2011 we issued to the investors: (i) 139,203 shares (the “Initial Shares”) of common stock, at a purchase price of $8.00 per share; (ii) series A warrants (the “Series A warrants”) which initially represented the right to purchase up to 104,402 shares of common stock, up to a maximum of 375,094 shares; and (iii) series B warrants (the “Series B

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warrants”) which initially represented the right to purchase up to 360,922 shares of common stock. In addition, we agreed to issue certain additional shares of common stock (the “Adjustment Shares”) to the extent the price of the common stock is below $8.00 per share, but greater than or equal to $4.50 per share, on certain dates (“Adjustment Dates”) during the period ended June 26, 2012, including as a result of a subsequent offering by us of our securities at a price below the purchase price of the Initial Shares. The number of Adjustment Shares issuable was initially limited to 108,207, subject to proportionate increases to the extent the Series B warrants have been exercised prior to the applicable Adjustment Date, up to a maximum of 388,764 shares. If the trading price of our common stock were to be below $4.50 per share on any Adjustment Date, we agreed, in addition to issuing the applicable number of Adjustment Shares, to refund to the investors an amount per share of common stock received by the investors in the transaction equal to the difference between $4.50 and the price of the common stock on such Adjustment Date. The transactions contemplated by the Amended Securities Purchase Agreement are referred to as the May 2011 private placement. Upon the closing of the May 2011 private placement, the Company also issued warrants to the placement agent for the purchase of up to 35,008 shares of common stock, which warrants were exercisable on the same terms as the Series A warrants.

On December 29, 2011, the Company issued an aggregate of 111,212 Adjustment Shares to the investors in accordance with the calculation of the applicable price, based on the trading price of the Company’s common stock, with respect to the first Adjustment Date. Additionally, on December 29, 2011, the Company issued an aggregate of 40,950 Adjustment Shares to the investors in connection with the private placement of common stock to Novogen that closed on December 29, 2011.

Terms of Series A and Series B Warrants

The Series A warrants became exercisable on the six month anniversary of the May 18, 2011 closing of the May 2011 private placement. The Series A warrants will expire on the fifth anniversary of the date on which the Series A warrants first became exercisable. Prior to the amendment of the warrant terms in September 2011 in conjunction with the Supplemental Agreement, as defined and described below, the Series A warrants were initially exercisable at an exercise price of $9.42 per share, subject to adjustment as provided in the Series A warrant agreements. Under the terms of the warrant agreements, the number of shares of common stock issuable upon exercise of the Series A warrants would be increased by an amount equal to 75% of the number of shares of common stock issued upon each exercise of the Series B warrants.

Prior to the amendment of the warrant terms in September 2011 in conjunction with the Supplemental Agreement, as described below, the initial exercise price per share of the Series B warrants was equal to the lower of (i) $8.00, and (ii) 85% of the arithmetic average of the lowest eight weighted average prices of the common stock during the 20 consecutive trading day period in the case of a voluntary exercise by the holders, ending on the trading day immediately preceding the date of delivery of a notice of exercise.

In July and August 2011, the investors exercised an aggregate of 215,667 Series B warrants for 215,667 shares of common stock. The Company received net proceeds of $1,094,000 in conjunction with the exercise of the Series B warrants. Pursuant to the terms of the Amended Securities Purchase Agreement, an additional 161,750 Series A warrants became exercisable as a result of the Series B warrant exercises.

Supplemental Agreement

On September 28, 2011, the Company entered into a Supplemental Agreement (the “Supplemental Agreement”) with each of the investors party to the Amended Securities Purchase Agreement.

Pursuant to the Supplemental Agreement, each of the Series A warrants and the Series B warrants issued pursuant to the Amended Securities Purchase Agreement were amended and restated (the “Amended Series A Warrants” and “Amended Series B Warrants”, respectively). The exercise price of each of the Series A warrants and Series B warrants was reduced to $6.00 per share. As amended, the exercise price of the Amended Series A Warrants is no longer subject to further adjustment upon the occurrence of certain events, including the

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subsequent sale or deemed sale by the Company of shares of common stock at a price per share below the exercise price of the Amended Series A Warrants; however, the Amended Series A Warrants continue to provide for certain customary anti-dilution adjustments.

The Series B warrants were amended to permit the exercise of such warrants on a cashless basis. Pursuant to the terms of the Supplemental Agreement, on September 28, 2011, the investors exercised, on a cashless basis, the Amended Series B Warrants for all of the remaining shares of common stock for which such Amended Series B Warrants were exercisable, resulting in the issuance by the Company of an aggregate of 50,934 shares of common stock. Pursuant to the terms of the Amended Securities Purchase Agreement, additional Series A warrants to purchase 108,942 shares of common stock became exercisable as a result of these Series B warrant exercises. As of September 28, 2011, there were no remaining outstanding Series B warrants.

In December 2012, the investors exercised, on a cashless basis, an aggregate of Series A warrants representing the right to purchase 194,381 shares of common stock. The Company issued 119,158 shares of common stock in conjunction with the exercise of the Series A warrants.

The Supplemental Agreement also effected certain amendments to the Amended Securities Purchase Agreement, including the extension, through September 28, 2013, of the period during which the investors have the right to participate in subsequent equity offerings of the Company. In connection with the amendments described above, the Company made cash payments to the investors in an aggregate amount of $365,000, which, together with $41,000 that the Company paid in other expenses related to the Supplemental Agreement, have been classified as ‘Financing Costs’ in the Statement of Operations for the year ended June 30, 2012.

Corporate Developments

Board of Directors and Management

In February 2013, we announced the appointment of Thomas C. Reynolds, M.D., Ph.D., to our board of directors. In March 2013, Christine White was appointed Lead Director following the retirement of Professor Bryan Williams, who had been serving as Chairman of our board of directors since 2006. In June 2013, we announced the appointment of Nicholas R. Glover, Ph.D., to our board of directors.

Critical Accounting Policies and Management Estimates

Management’s discussion and analysis of our financial condition and results of operations is based on our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, expenses and related disclosures. Actual results could differ from those estimates. We believe the following accounting policies to be critical to the judgments and estimates used in the preparation of our financial statements.

Clinical Trials Expenses

Estimates have been used in determining the expenses under certain clinical trial contracts where services have been performed but not yet invoiced. Generally, the costs associated with clinical trial contracts are based on the number of patients in each trial, the service contracts associated with clinical sites, service providers and drug development contracts. The length of time before actual amounts can be determined will vary, and are therefore estimated, depending on length of the drug administration cycles and the timing of the invoices by the clinical trial partners and contractors.

Share-Based Compensation

Share-based compensation expense for employees and directors is recognized in the statement of operations based on estimated amounts, including the grant date fair value and the expected service period. For

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stock options, we estimate the grant date fair value using a binomial valuation model, which requires the use of multiple subjective inputs including estimated future volatility, expected forfeitures and the expected term of the awards. We estimate our expected future volatility based on our stock’s historical price volatility. Our stock’s future volatility may differ from our estimated volatility at the grant date. For restricted stock units (RSU) equity awards, we estimate the grant date fair value using the Company’s closing stock price on the date of grant. Share-based compensation recorded in our statement of operations is based on awards expected to ultimately vest and has been reduced for estimated forfeitures. Our estimated forfeiture rates may differ from actual forfeiture rates which would affect the amount of expense recognized during the period. We recognize the value of the awards on a straight-line basis over the awards’ requisite service periods. The requisite service period is generally the time over which our share-based awards vest. Unrecognized compensation expense as of June 30, 2013 related to non-vested stock options and RSUs totalled $1,948,000 and $3,039,000, respectively. Such compensation expense is expected to be recognized over weighted-average periods of 3.3 years and 3.2 years, respectively.

Derivative Liabilities

In conjunction with our May 2011 private placement, we issued common stock on terms that included certain embedded derivative features, as well as warrants that were accounted for as derivative liabilities. The Series A and Series B warrants, prior to their subsequent amendment in September 2011, and adjustment shares features related to the common stock issued in the private placement, were determined to be ineligible for equity classification due to certain price protection and anti-dilution provisions. The resulting derivative liabilities were initially recorded at their estimated fair value on the date of issuance of the common stock and warrants, and were subsequently adjusted to reflect the estimated fair value at each period end, with any decrease or increase in the estimated fair value being recorded as other income or expense. The fair value of these liabilities was estimated using option pricing models that are based on the individual characteristics of the common stock, the derivative liabilities on the valuation date, probabilities related to future financings, as well as assumptions for volatility, remaining expected life, and risk-free interest rate. The option pricing models of our derivative liabilities are sensitive to changes to inputs and assumptions used in the option pricing models. As of June 30, 2013 and June 30, 2012 we had no remaining derivative liabilities.

Results of Operations

We are providing the following summary of our research and development expenses and general and administrative expenses to supplement the more detailed discussions below. The dollar values in the following tables are in thousands.

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Comparison of Years Ended June 30, 2013 and 2012

Research and Development: Research and development expenses consist primarily of clinical trial costs (including payments to contract research organizations, or CROs), pre-clinical study costs, cost to manufacture our drug candidates for non-clinical and clinical studies, and salaries and other personnel costs.

Research and development expenses increased $1,169,000 to $6,084,000 for the year ended June 30, 2013 compared to $4,915,000 for the year ended June 30, 2012. The increase was primarily due to costs associated with drug manufacturing and preparations for Phase II clinical trials for Pracinostat and costs associated with a Phase I clinical trial for ME-344. Additionally, salaries and benefits costs, including share-based compensation, increased due to hiring of additional employees and issuance of additional stock options to research and development personnel. We expect research and development expenses to increase during the fiscal year ending June 30, 2014 related primarily to our planned Phase II clinical trials for Pracinostat.

General and Administrative: General and administrative expenses increased by $1,659,000 to $5,138,000 for the year ended June 30, 2013 compared to $3,479,000 for the year ended June 30, 2012. The increase primarily relates to higher levels of salaries and benefits, including share-based compensation of $1,292,000 for the year ended June 30, 2013 compared with $446,000 for the year ended June 30, 2012. In addition, we incurred legal fees and other costs associated with the issuance of common stock to S*Bio in conjunction with the purchase of Pracinostat, and professional and consulting expenses related to corporate matters including the Company’s reverse stock split.

Other income or expense: We received interest on cash and cash equivalents of $37,000 for the year ended June 30, 2013 and $10,000 for the year ended June 30, 2012. The increase was due to higher cash balances. We also received dividends of $29,000 from a small investment in a privately-held company during the year ended June 30, 2012. We recognized a gain of $100,000 during the year ended June 30, 2012 from the sale of this investment.

Additionally, during the year ended June 30, 2011, we issued securities that were accounted for as derivative liabilities. As of June 30, 2012, our obligations related to these securities were contractually completed, resulting in the elimination of the derivative liabilities and a corresponding net decrease in their value of $1,139,000 during the year ended June 30, 2012, which was recorded as non-operating income. In connection with the Supplemental Agreement entered into in September 2011 with the investors in the May 2011 private placement, we incurred financing costs in the amount of $406,000 during the year ended June 30, 2012.

Recent Accounting Pronouncements

No recent accounting pronounements or other authoritative guidance have been issued that are considered likely to have a material impact on our financial statements.

Off-Balance Sheet Arrangements

We do not currently have any off-balance sheet arrangements.

Liquidity and Capital Resources

We have accumulated losses of $96.3 million since inception and expect to incur operating losses and generate negative cash flows from operations for the foreseeable future. As of June 30, 2013, we had $35.6 million in cash and cash equivalents. We believe our cash and cash equivalents will be sufficient to fund our operations for at least the next 12 months. Our current business operations are focused on continuing the clinical development of our lead drug candidate, Pracinostat. Our clinical development pipeline also includes ME-344 and ME-143. Changes to our research and development plans or other changes affecting our operating

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expenses may affect actual future use of existing cash resources. To date, we have obtained cash and funded our operations primarily through equity financings. In order to continue the development of our drug candidates, at some point in the future we expect to pursue one or more capital transactions, whether through the sale of equity securities or entry into strategic partnerships.

Sources and Uses of Our Cash

Net cash used in operations for the year ended June 30, 2013 was $10,044,000 compared to $7,081,000 in the year ended June 30, 2012 due to an increase in expenses incurred for research and development and general and administrative costs as described above.

Net cash used in investing activities of $38,000 for the year ended June 30, 2013 was for the purchase of property and equipment. We did not use any cash in investing activities during the year ended June 30, 2012.

Net cash provided by financing activities was $39,453,000 during the year ended June 30, 2013 compared with $9,425,000 during the year ended June 30, 2012. Cash raised during the year ended June 30, 2013 reflected $39,453,000 in net proceeds received associated with the issuance of common stock. Cash raised during the year ended June 30, 2012 reflected $9,831,000 net proceeds received associated with the issuance of common stock. Additionally, during the year ended June 30, 2012 we paid $406,000 in financing costs associated with amending the terms of securities that had been issued as part of the May 2011 private placement.

Contractual Obligations

We have contracted with various consultants and third parties to assist us in pre-clinical research and development and clinical trials work for our leading drug compounds. The contracts are terminable at any time, but obligate us to reimburse the providers for any time or costs incurred through the date of termination. Additionally, we have employment agreements with certain of our current employees that provide for severance payments and accelerated vesting for share-based awards if their employment is terminated under specified circumstances.

In July 2010, we entered into a lease arrangement to rent approximately 3,700 square feet of office space for 33 months beginning in July 2010 for monthly rental rates ranging from $10,109 to $10,734 over the lease term, plus other pass-through charges. On January 3, 2013, we entered into an amendment to the lease (“First Lease Amendment”). The First Lease Amendment extends the lease term through June 2015. In addition, it adds expansion space of approximately 2,500 square feet of office space, which co-terminates with the extension of the original lease in June 2015. The additional expansion space portion of the lease began in February 2013. We currently lease approximately 6,200 square feet of space at a monthly rental rate of $17,014 to $18,252 during the term of the lease.

License Agreement

On September 28, 2012, the Company entered into a license agreement with CyDex Pharmaceuticals, Inc. (“CyDex”). Under the license agreement, CyDex granted to the Company an exclusive, nontransferable license to intellectual property rights relating to Captisol^® for use with the Company’s two isoflavone-based drug compounds. The Company agreed to pay to CyDex a non-refundable license issuance fee, future milestone payments, and royalties at a low, single-digit percentage rate on future sales of the Company’s approved drugs utilizing Captisol. Contemporaneously with the license agreement, the Company and CyDex entered into a commercial supply agreement pursuant to which the Company agreed to purchase 100% of its requirements for Captisol from CyDex. The Company may terminate both the license agreement and the supply agreement for convenience at any time upon 90 days’ prior written notice.

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Interest Rate Risk

Our exposure to market interest rates relates primarily to the investment of cash balances. We have cash reserves held in U.S. dollars and we place funds on deposit with financial institutions which are readily available.

We do not use derivative financial instruments to hedge our risks related to cash balances. We place our cash deposits with high credit quality financial institutions, and, by policy, limit the amount of credit exposure to any single counter-party. We are adverse to principal loss and we ensure the safety and preservation of our invested funds by limiting default risk, market risk and reinvestment risk. We seek to mitigate default risk by depositing funds with high credit quality financial institutions and by positioning our portfolio, when necessary, to respond appropriately to a significant reduction in a credit rating of any financial institution.

We do not consider the effects of interest rate movements to be a material risk to our financial condition.

MEI Pharma, Inc.

Index to Financial Statements

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Report of Independent Registered Accounting Firm

The Board of Directors and Stockholders of MEI Pharma, Inc.

We have audited the accompanying balance sheets of MEI Pharma, Inc. (a development stage company) as of June 30, 2013 and 2012, and the related statements of operations, stockholders’ equity, and cash flows for the years ended June 30, 2013 and 2012 and for the period from inception (December 1, 2000) to June 30, 2013. These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the financial position of MEI Pharma, Inc. as of June 30, 2013 and 2012, and the results of its operations and its cash flows for the years ended June 30, 2013 and 2012 and for the period from inception (December 1, 2000) to June 30, 2013 in accordance with accounting principles generally accepted in the United States of America.

/s/ BDO USA, LLP

San Diego, California

September 17, 2013

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MEI PHARMA, INC.

(A Development Stage Company)

BALANCE SHEETS

(In thousands, except share and per share amounts)

See accompanying notes to financial statements.

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MEI PHARMA, INC.

(A Development Stage Company)

STATEMENTS OF OPERATIONS

(In thousands, except share and per share amounts)

See accompanying notes to financial statements.

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MEI PHARMA, INC.

(A Development Stage Company)

STATEMENT OF STOCKHOLDERS’ EQUITY

(In thousands, except share amounts)