Alkermes' shares tank as MMD drug candidate fails in late-stage trials

Shares of Ireland-incorporated biotech Alkermes (Nasdaq: ALKS) plunged 44.2% to $33.71 by the close of trading on Thursday, wiping nearly $4 billion from its market capitalization, after it announced disappointing preliminary top-line results from FORWARD-3 and FORWARD-4.

These were the first two of three Phase III efficacy studies to read out from the comprehensive FORWARD pivotal program for ALKS 5461, a once-daily, oral investigational medicine with a novel mechanism of action for the adjunctive treatment of major depressive disorder (MDD) in patients who have an inadequate response to standard therapies for clinical depression. The market for MDD drugs is estimated at around $9 billion a year, with slow growth predicted due to patent expiries for leading treatments.

Neither of the two studies met the pre-specified primary efficacy endpoint, which compared ALKS 5461 to placebo on the change from baseline on the Montgomery–Åsberg Depression Rating Scale (MADRS). ALKS 5461 is a combination of two drugs, buprenorphine and samidorphan.