New treatment hope is emerging for people living with Narcolepsy Type 2 (NT2), a debilitating condition characterised by excessive daytime sleepiness and disrupted sleep patterns. Researchers from Alkermes plc have presented the results of their Vibrance-2 Phase 2 study at the SLEEP 2026 conference, revealing that their investigational drug, alixorexton, shows promise in improving wakefulness and reducing fatigue in NT2 patients.
The Vibrance-2 study involved 93 adult participants who took part in a dose-ranging trial of once-daily alixorexton across various doses (10 mg, 14 mg, and 18 mg). The drug successfully met its two primary objectives: demonstrating statistically significant and clinically meaningful improvements from baseline compared to a placebo on both the Maintenance of Wakefulness Test (MWT) and the Epworth Sleepiness Scale (ESS) after eight weeks. For instance, participants who typically had a mean sleep latency of around six minutes at baseline saw this increase to approximately 14-16 minutes at week eight across the effective doses.
Beyond the primary endpoints, the study also highlighted clinically meaningful improvements in exploratory patient-reported outcomes (PROs). These included reductions in fatigue and enhanced cognitive function, which were observed as early as two weeks into treatment and continued to improve through a 13-week period. Participants who initially reported severe excessive daytime sleepiness with a mean ESS score of approximately 17 largely reported normal or mild sleepiness by week eight, with scores falling within the normal range by week 13.
Commenting on the results, Dr. Richard K. Bogan, Principal of Bogan Sleep Consultants, LLC, noted that alixorexton meaningfully improved measures of wakefulness, fatigue, and cognition. He highlighted the significance of these findings for NT2 patients, particularly in light of positive data from the Vibrance-1 study in Narcolepsy Type 1, suggesting that alixorexton could be a broad new treatment option for narcolepsy patients.
Narcolepsy is a chronic neurological condition caused by the brain's inability to regulate sleep-wake cycles normally, leading to excessive daytime sleepiness and other symptoms. NT2 differs from Type 1 in not involving cataplexy or hypocretin deficiency, making it a challenging condition to treat. Current treatments often focus on managing symptoms, and new targeted therapies are eagerly sought after to improve quality of life for patients.
The drug was generally well tolerated across all doses tested, with no significant safety concerns raised by the researchers. However, further studies will be needed to fully assess its potential and long-term effects in NT2 patients.