Alkermes heads to Phase III with a schizophrenia drug designed to spare the waistline

Alkermes ($ALKS) unveiled more positive data for a schizophrenia drug the company believes can treat the disease without spurring weight gain, beating a path to late-stage development.

The treatment, ALKS 3831, combines the common antipsychotic olanzapine with a mu-opioid antagonist called samidorphan. In a Phase II study comparing it to olanzapine alone, Alkermes' drug met its primary endpoint of matching the old treatment's efficacy and demonstrated favorable effects on weight gain. And in the second segment of the study, patients receiving olanzapine were switched onto ALKS 3831, a change that led to a cessation of mean weight gain, the company said.

In the first three months of the trial, patients taking olanzapine increased their body weight by 4.3% on average, Alkermes said, but they charted just a 0.1% gain after changing over to ALKS 3831 for the second three months. Meanwhile, those who received Alkermes' drug the whole time posted a 0.5% mean change in body weight, which the company said affirms ALKS 3831's promise.

Now, with 6 months of Phase II data in hand, Alkermes plans to meet with the FDA to go over the design of a Phase III study, expecting to kick off pivotal development this year.

Alkermes CMO Dr. Elliot Ehrich

"ALKS 3831 is a new antipsychotic designed with the real-world needs of patients in mind and introduces a novel and expanded pharmacologic approach to the treatment of schizophrenia," Chief Medical Officer Dr. Elliot Ehrich said in a statement.

The drug is emblematic of Alkermes guiding philosophy, in which it takes established therapeutics and uses new formulations or novel drug delivery to improve upon them. In olanzapine's case, weight gain has long been a serious and clinically relevant side effect among widely prescribed antipsychotics, and Alkermes figures there's great market demand for a treatment that can match its efficacy without replicating its side effects.

Meanwhile, Alkermes is moving forward with ALKS 8700, an oral multiple sclerosis treatment designed to compete with Biogen's ($BIIB) blockbuster Tecfidera, and the Phase III depression treatment ALKS 5461.

- read the statement

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