FDA issues Refusal to File letter for ALKS 5461 to treat major depressive disorder.-Alkermes plc.

Alkermes plc announced that it received a Refusal to File letter from the FDA regarding its New Drug Application (NDA) 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 with an inadequate response to standard antidepressant therapies.

Upon its preliminary review, the FDA has taken the position that it is unable to complete a substantive review of the regulatory package, based on insufficient evidence of overall effectiveness for the proposed indication, and that additional well-controlled clinical trials are needed prior to the resubmission of the NDA for ALKS 5461. In addition, FDA has requested the conduct of a bioavailability study to generate additional bridging data between ALKS 5461 and the reference listed drug, buprenorphine. Alkermes strongly disagrees with the FDA's conclusions and plans to appeal the FDA's decision. The company intends to seek immediate guidance, including requesting a Type A meeting with the FDA, to determine appropriate next steps and what additional information may be required to resubmit the NDA.