Alkermes has reported a midphase win in narcolepsy type 1 (NT1), keeping up the pressure on Takeda’s near-approval rival for the blockbuster opportunity.
Both companies hit upon the idea of improving the quantity and quality of wakefulness in NT1 patients by addressing orexin deficiencies. Takeda racked up a pair of phase 3 wins for its prospect last week, putting the company on track to file for approval this year. Alkermes’ program is further back, but the biotech is racing to close the gap on Takeda’s frontrunner.
Alkermes outlined plans to move its NT1 drug candidate, alixorexton, into phase 3 after posting results from the midstage Vibrance-1 study. The trial randomized 92 adults with NT1 to take one of three doses of alixorexton or placebo once daily.
After six weeks, Alkermes saw statistically significant improvements over placebo on a wakefulness test at all three doses, achieving the primary endpoint of the study. The biotech said patients in all three dose cohorts achieved “normative wakefulness,” meaning sleep latency rose to longer than 20 minutes, but it is yet to provide further data on the primary endpoint.
Alkermes saw significant improvements in excessive daytime sleepiness. Rates of cataplexy, sudden muscle weakness linked to NT1, fell in all alixorexton cohorts versus placebo, but only the middle dose was statistically significant. Exploratory patient-reported outcome measures favored alixorexton, too.
No patients reported treatment-emergent serious adverse events and most side effects were mild to moderate in severity. No treatment-related safety signals were seen in eye exams. Jazz Pharmaceuticals stopped a phase 1 trial of its narcolepsy prospect in 2023 over reports of “visual disturbances.” Alkermes has seen visual disturbances in other sleep indications at higher doses.
Talking at a Goldman Sachs event in June, Alkermes CEO Richard Pops said Takeda’s candidate is “proof of the pharmacology, but it’s an incomplete product.” Pops’ view reflects the fact Takeda’s molecule is given once in the morning and again a few hours later and is only on course to come to market in NT1.
“It opens up a huge vulnerability from a commercial perspective for a drug that could be across all the indications with a range of doses given once a day. And hopefully, that's what we have,” Pops said.