DUBLIN, Nov. 30, 2018 /PRNewswire/ — Alkermes plc (Nasdaq: ALKS) today announced positive topline results from ENLIGHTEN-2, a pivotal phase 3 study of ALKS 3831 (olanzapine/samidorphan), an investigational, novel, once-daily, oral atypical antipsychotic drug candidate for the treatment of schizophrenia. ENLIGHTEN-2 is the second of two key phase 3 studies in the ALKS 3831 registration program and was designed to confirm ALKS 3831’s favorable weight profile compared to olanzapine, an antipsychotic agent with established efficacy but limited in its clinical use by a high incidence and magnitude of weight gain.
ENLIGHTEN-2 was a multicenter, double-blind, randomized, phase 3 study that evaluated the weight gain profile of ALKS 3831 compared to olanzapine over six months in 561 patients with stable schizophrenia. In the study, ALKS 3831 met the pre-specified co-primary endpoints, demonstrating both a lower mean percent weight gain from baseline at six months compared to the olanzapine group (p=0.003) and a lower proportion of patients who gained 10% or more of their baseline body weight at six months compared to the olanzapine group (p=0.003). With the successful completion of ENLIGHTEN-2, Alkermes plans to submit a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) in mid-2019.
In addition to meeting the co-primary endpoints, the study also met its pre-specified key secondary endpoint, with the ALKS 3831 treatment group demonstrating a lower proportion of patients who gained 7% or more of their baseline body weight at six months compared to the olanzapine group (p=0.001). Consistent with the phase 2 study of ALKS 3831, the weight gain curves for the ALKS 3831 and olanzapine treatment groups began to separate after Week 4 and continued to diverge for the remainder of the study. For the ALKS 3831 treatment group, weight stabilized at Week 6 and remained flat for the rest of the six-month treatment period.
“These unequivocal results from ENLIGHTEN-2 provide evidence of a clinically meaningful, differentiated weight profile for ALKS 3831 compared to olanzapine. Importantly, ALKS 3831 favorably shifted the weight gain distribution curve compared to olanzapine, both in terms of mean weight gain and patients experiencing extreme weight gain,” said Craig Hopkinson, M.D., Chief Medical Officer and Senior Vice President of Medicines Development and Medical Affairs at Alkermes. “These findings build on the positive safety and efficacy profile seen throughout the ENLIGHTEN development program, and underscore the potential of ALKS 3831 to provide an important benefit for people living with schizophrenia. With these data now in hand, we will meet with the FDA and plan to submit a New Drug Application in mid-2019.”
“Significant unmet patient need remains in schizophrenia despite the number of treatment options available. A new agent that offers the robust efficacy of olanzapine but with a favorable weight profile that stabilizes within weeks of treatment initiation would be an important and differentiated addition to the treatment armamentarium for schizophrenia,” said Christoph Correll, M.D., Professor of Psychiatry and Molecular Medicine at Hofstra Northwell School of Medicine. “People living with schizophrenia deserve treatment options that do not sacrifice tolerability for efficacy. A new therapeutic option with the profile demonstrated by ALKS 3831 in this study would be clinically meaningful for patients and their healthcare providers.”