MEI Pharma and its Swiss partner Helsinn are ending a Phase 3 study of an investigational cancer drug for patients with acute myeloid leukemia (AML) after an interim analysis indicated it was unlikely to meet the trial’s main goal of helping patients live longer.
San Diego-based MEI (NASDAQ: MEIP), licensed the compound, pracinostat, from a Singaporean biotech company in 2013. In August 2016 MEI signed an alliance with Helsinn to advance the experimental drug for patients newly diagnosed with AML who are unable to receive intensive chemotherapy due to advanced age—75 years or older—or other health reasons.
Under the deal terms Helsinn took primary responsibility for development and commercialization costs for pracinostat in AML and in certain other indications.
On Thursday the companies announced the early end of the AML trial based on the lack of efficacy indicated by the preliminary data. Shares of MEI slid 18 percent to $3.49 apiece as of market close.
The average age of diagnosis for patients with AML, a cancer of the blood and bone marrow, is age 68, according to the American Cancer Society. Intensive chemotherapy puts AML into remission for about 35 percent to 40 percent of patients age 60 or younger, but that rate falls to about 15 percent for older patients, according to the companies.
The AML study was evaluating pracinostat in combination with azacytidine, a chemotherapy with less intense side effects than standard chemo drugs. The goal was to measure the survival rate of the patients who were taking the drug combination compared to a control group treated with chemotherapy alone. No safety concerns arose in the interim analysis, the companies said.
Despite the failure in AML, MEI and Helsinn are continuing at least one other clinical trial testing pracinostat. A Phase 2 study is ongoing in patients with myelodysplastic syndromes (MDS), a type of cancer characterized by abnormalities in the blood-forming cells in the bone marrow, who are considered high- or very high-risk.
The partnership Helsinn struck with MEI is part of an effort to expand its portfolio beyond what it calls cancer “supportive care” products, such as anti-emetics for patients receiving chemotherapy, into oncology therapeutics.
Separately MEI is advancing three other experimental drugs; the most advanced, ME-401, in partnership with Japan’s Kyowa Kirin. That drug is being evaluated in a Phase 2 study in patients with follicular lymphoma that has returned or stopped responding to treatment, an evaluation that could suffice for an FDA submission under the agency’s accelerated approval pathway.