Axsome Therapeutics’ Small Molecule AXS-12 Successful in Phase III Narcolepsy Trial

1. Axsome Therapeutics announced that its small molecule drug, AXS-12 (reboxetine), achieved the primary endpoint in the SYMPHONY Phase 3 clinical trial for narcolepsy.
2. The study found AXS-12 to be fast-acting with substantially better results than placebo at reducing excessive daytime sleepiness, improving cognitive function and memory, and combating cataplexy—a sudden loss of muscle tone.
3. AXS-12 significantly reduced weekly cataplexy attacks by 56% one week into treatment compared to a 31% reduction in the placebo arm; rates were down 83% and 66%, respectively, after five weeks.
4. AXS-12 also induced "cataplexy remission" more often than placebo, where participants experienced no episodes of cataplexy.
5. The drug improved patient function, quality of life, anxiety, depression, and overall severity of narcolepsy when compared to placebo.
6. Adverse events reported during the trial included dry mouth, nausea, constipation, which were mild to moderate. No serious adverse events occurred.
7. Axsome is conducting an open-label extension study to assess long-term safety and effectiveness of AXS-12, aiming to submit an approval application within six months once the database of safety information is complete.
8. Shares of Axsome declined slightly on Monday morning following the announcement.
9. The placebo response rate for cataplexy attacks was higher than expected, which analysts noted as a potential concern.
10. AXS-12 joins Axsome Therapeutics' portfolio of sleep disorder therapies, including Sunosi, approved by the FDA to improve wakefulness in adults with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea.