Alkermes Reports Disappointing Trial Results For Depression Drug

Alkermes PLC on Thursday said two late-stage studies of its treatment for major depressive disorder didn't meet their primary endpoints, a significant setback for the company, erasing nearly a third of its market value.

The Dublin-based biopharmaceutical is developing ALKS 5461, a once-daily, oral medication medicine for the adjunctive treatment of major depressive disorder in patients who have an inadequate response to standard therapies for clinical depression.

The first two of three Phase 3 efficacy studies, Forward-4 and Forward-3, didn't meet the prespecified primary efficacy endpoint, which compared the drug to placebo. However, the company said "there was a clear trend toward efficacy" in the one of the dose levels in the Forward-4 trial.

"Based on these analyses, Alkermes believes that FORWARD-4 provides supportive evidence of the efficacy of ALKS 5461 in the treatment of major depressive disorder," the company said.

Nonetheless, shares of Alkermes sank on the news, falling 30% to $42.44 in premarket trading. Such a drop would wipe away about $2.7 billion in Alkermes' market cap.

Analysts had speculated that the trial's results would have a significant impact on Alkermes' stock because of the drug's market opportunity. In addition, analysts had said, the results could make the company a more or less attractive takeover target in the near term.

Alkermes noted the strong patient response to taking the placebo, particularly in the Forward-3 trial, and said negative trials because of a significant placebo effect aren't uncommon in the study of major depressive disorder.

"Clinical trials of new medicines for the treatment of major depressive disorder are complicated by significant placebo response," Chief Medical Officer Elliot Ehrich said.

Alkermes' third Phase 3 study, Forward-5, is ongoing. Patient enrollment will be increased, and statistical analysis will be updated based on results from the previous two studies. An update on the study is expected later in the quarter.

If the Forward-5 study shows a clear positive outcome, Alkermes said that evidence in combination with its successful mid-stage study and Forward-4 study could build a case to bring to the U.S. Food and Drug Administration.

Write to Anne Steele at [e-mail]

(END) Dow Jones Newswires

January 21, 2016 08:55 ET (13:55 GMT)

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