Interim data further support potential of ME-344 to reverse resistance to antiangiogenic therapy

SAN DIEGO, CA, USA I February 13, 2018 I MEI Pharma, Inc. (NASDAQ: MEIP), an oncology company focused on the clinical development of novel therapies for cancer, today announced that a planned interim review of data supports continuation of its multicenter, investigator sponsored, study evaluating ME-344, a novel mitochondrial inhibitor, in patients with HER2-negative breast cancer. The interim study data show that ME-344 was generally well-tolerated and, consistent with previous preclinical data, demonstrate the potential to reverse resistance to antiangiogenic therapy. Based on the interim results, it was determined that completion of enrollment of the clinical study of ME-344 in combination with bevacizumab (marketed as Avastin®) is warranted.

“The interim data are very encouraging and I look forward to an opportunity to present the results at a medical meeting later this year,” stated the study principal investigator, Miguel Quintela-Fandino, M.D., Ph.D., Director of the Clinical Research Program, Centro Nacional De Investigaciones Oncologicas, Madrid, Spain.

Dr. Quintela-Fandino continued: “These preliminary data are consistent with our previously published preclinical studies and it is our hope that the data from the current clinical study will help advance our understanding of the escape pathways utilized by tumors against antiangiogenic agents. The therapeutic opportunity that is available to exploit the adaptive mechanisms of tumors via mitochondrial inhibition is quite novel and I am very excited to continue the trial and further explore the promising utility of ME-344 in combination with antiangiogenic therapeutics.”

Inhibition of mitochondrial adenosine triphosphate (ATP) with drug candidates such as ME-344 may have significant potential in combination with antiangiogenic agents. Antiangiogenics are widely used biologic agents in oncology, but acquired resistance to antiangiogenics is a major problem in cancer therapeutics. Antiangiogenics reduce the rate of glycolysis as a mechanism to block tumor growth, however sustained tumor growth may be achieved via a shift to an alternative metabolic energy source such as mitochondrial ATP*. In such cases of tumor plasticity in the presence of treatment with antiangiogenics, targeting the alternative metabolic source would open an important therapeutic opportunity.

About the Study
The study is a multicenter, investigator sponsored, randomized, open label, clinical trial evaluating ME-344 in a total of 40 patients with HER2-negative breast cancer in combination with the VEGF inhibitor bevacizumab (marketed as Avastin®).  Patients are randomized one-to-one to either ME-344 plus Avastin or saline plus Avastin. The primary efficacy endpoint is inhibition of cell proliferation as measured by Ki-67 reductions. The interim data review was predefined to take place after 20 patients were randomized.

About ME-344
ME-344 is a novel, tumor selective, isoflavone-derived mitochondrial inhibitor drug candidate. It directly targets the OXPHOS complex 1**, a pathway involved in the production of adenosine triphosphate, or ATP, in the mitochondria. Treatment of tumor cells with ME-344 results in a rapid loss of ATP and cancer cell death. ME-344 has demonstrated evidence of single agent activity against refractory solid tumors in a Phase 1 study.***

About MEI Pharma
MEI Pharma, Inc. (Nasdaq: MEIP) is a San Diego-based oncology company focused on the clinical development of novel therapies for cancer. The Company’s portfolio of drug candidates includes pracinostat, an oral HDAC inhibitor that is partnered with Helsinn Healthcare, SA. Pracinostat has been granted Breakthrough Therapy Designation from the U.S. Food and Drug Administration for use in combination with azacitidine for the treatment of patients with newly diagnosed acute myeloid leukemia (AML) who are unfit for intensive chemotherapy. Pracinostat is also being developed in combination with azacitidine for the treatment of patients with high and very high-risk myelodysplastic syndrome (MDS) (NCT03151304). MEI Pharma’s clinical development pipeline also includes ME-401, a highly differentiated oral PI3K delta inhibitor currently in a Phase 1b study in patients with relapsed/refractory CLL or follicular lymphoma, and voruciclib, an oral, selective CDK inhibitor shown to suppress MCL1, a known mechanism of resistance to BCL2 inhibitors. The Company is also developing ME-344, a novel mitochondrial inhibitor currently in an investigator-sponsored study in combination with bevacizumab for the treatment of HER2-negative breast cancer. Pracinostat, ME-401, ME-344 and voruciclib are investigational agents and are not approved for use in the U.S. For more information, please visit www.meipharma.com.

References 
* Cell Reports. 2016 June 21;15:2705-2718
** Am J Cancer Res. 2015 Jan 15:5(2):689-701.
*** Cancer. 2015 APR 1;121(7): 1056-63.

SOURCE: MEI Pharma