AXS-12 Achieves Phase III Success in Narcolepsy Treatment

Axsome Therapeutics has reported that its drug candidate, AXS-12, has successfully shown significant improvements in the Phase III SYMPHONY trial for patients suffering from narcolepsy. The drug demonstrated its efficacy by reducing cataplexy attacks, which are sudden losses of muscle tone while awake, by 83% after week 5, a substantial improvement over the placebo group's 66% reduction. The reduction was statistically significant, with a p-value of 0.018.

The trial, which was randomized, double-blinded, and placebo-controlled, enrolled 90 patients with narcolepsy. AXS-12 was administered once daily initially, and then twice daily from the second to the fifth week. The rapid onset of the drug was also notable, as it reduced cataplexy attacks by 56% at week 1, compared to a 31% reduction in the placebo group.

Furthermore, the SYMPHONY trial indicated that 33% of the patients treated with AXS-12 achieved complete remission of cataplexy by week 5, a stark contrast to the 9.5% seen in the placebo group. The CEO of Axsome, Herriot Tabuteau, emphasized the positive therapeutic impact of AXS-12, highlighting its rapid and substantial reduction in cataplexy events and significant improvements in other efficacy metrics such as quality of life and functional performance.

The ongoing open label safety extension trial for AXS-12 is expected to be completed, and Axsome is working towards making this treatment available to individuals with narcolepsy. The SYMPHONY trial also evaluated AXS-12's impact on other symptoms of narcolepsy, revealing that the drug could significantly improve excessive daytime sleepiness and cognitive function within five weeks.

In terms of safety, the trial found AXS-12 to be well-tolerated, with most adverse events being mild to moderate. Only one patient in the AXS-12 group withdrew from the study due to side effects, and no serious adverse events were reported.

AXS-12, also known as reboxetine, is a small molecule drug with dual mechanisms of action. It blocks the reuptake of the hormone noradrenaline to regulate noradrenergic activity and maintain muscle tone during wakefulness, while also adjusting cortical dopamine levels to enhance wakefulness and cognition. The drug has previously received the FDA's Orphan Drug Designation, which could provide it with seven years of marketing exclusivity in the U.S. upon regulatory approval.