Alkermes Announces Positive Topline Results From Phase 1b Study of ALKS 2680 Demonstrating Improved Wakefulness in Patients With Narcolepsy Type 2 and Idiopathic Hypersomnia

— Orexin 2 Receptor Agonist ALKS 2680 Demonstrated Clinically Meaningful and Statistically Significant Improvements from Baseline in Mean Sleep Latency Compared to Placebo at All Doses Tested in Both Narcolepsy Type 2 and Idiopathic Hypersomnia —

— ALKS 2680 Was Generally Well Tolerated at All Doses Tested —

— Dose-Dependent Effects and Pharmacodynamic Profile Support Advancement Into Planned Phase 2 Study —

DUBLIN, April 9, 2024 /PRNewswire/ -- Alkermes plc (Nasdaq: ALKS) today announced positive topline results from the narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH) cohorts of a phase 1b, proof-of-concept study evaluating ALKS 2680, the company's novel, investigational, oral orexin 2 receptor (OX2R) agonist in development as a once-daily treatment for narcolepsy. ALKS 2680 data demonstrated clinically meaningful and statistically significant improvements from baseline in mean sleep latency on the Maintenance of Wakefulness Test (MWT) compared to placebo at all doses tested. ALKS 2680 was generally well tolerated in both patient populations at all doses tested.

The phase 1b NT2 (n=9) and IH (n=8) study cohorts evaluated the safety, tolerability, pharmacokinetics and pharmacodynamics of ALKS 2680 via once-daily, single, oral administration. Participants were randomized to a four-way crossover study in which each participant received 5 mg, 12 mg and 25 mg of ALKS 2680, and placebo, with washout periods between each treatment. Topline results from each cohort are as follows:

Narcolepsy Type 2:

• In the nine patients with NT2, treatment with ALKS 2680 demonstrated improved wakefulness compared to placebo at all doses tested, with a clear dose response. Prior to treatment with ALKS 2680, these patients had baseline sleep latencies ranging from 3 to 33 minutes, with a mean sleep latency of 14 minutes at baseline. Treatment with ALKS 2680 resulted in statistically significant and clinically meaningful improvements in sleep latency in these patients with NT2, with a mean change from baseline versus placebo of 12 minutes at the 5 mg dose (p