Samelisant (SUVN-G3031) - Topline Results from the Phase-2 Proof-of-Concept Double-blind, Placebo-controlled Study in Patients with Narcolepsy
Ramakrishna Nirogi1, Pradeep Jayarajan2, Vijay Benade3, Vinod Goyal2, Anil Shinde2, Jyothsna Ravula2, Satish Jetta2, Venkat Jasti2
1Drug Discovery and Development, Suven Life Sciences, 2Suven Life Sciences, 3Suven Life Sciences Ltd
Objective:
To evaluate the safety, and efficacy of samelisant (SUVN-G3031) in narcolepsy patients with and without cataplexy
Background:
Samelisant is potent and selective histamine-3 receptor inverse agonist. In orexin knockout mice, samelisant produced wake-promoting and anticataplectic effects suggesting its potential therapeutic utility in the treatment of narcolepsy. Safety and tolerability studies in animals and healthy human volunteers suggested a favorable risk/benefit profile for samelisant.
Design/Methods:

Samelisant was evaluated as monotherapy in a Phase-2 trial for the treatment of narcolepsy with and without cataplexy (ClinicalTrials.gov Identifier: NCT04072380). Subjects diagnosed with narcolepsy as per ICSD-3 criteria, aged between 18 to 65 years with an Epworth Sleepiness Scale (ESS) score of ≥12 and mean Maintenance of Wakefulness Test (MWT) time of <12 min were eligible for the study. A total of 171 subjects were randomized into one of three treatment arms (placebo, samelisant 2 mg and samelisant 4 mg) in 1:1:1 ratio. Each subject received either placebo or samelisant once daily for 2 weeks. The primary efficacy endpoint is a change in ESS score from baseline to week 2. Secondary endpoints are changes in MWT and CGI-S scores from baseline to week 2. Safety was monitored throughout the study by the medical monitor and by the data safety monitoring committee.

Results:
The study met pre-specified primary endpoint. Samelisant demonstrated a statistically significant and clinically meaningful 2.1-point reduction in excessive daytime sleepiness measured ESS total score compared to placebo at Week 2 (p<0.024). This primary efficacy result was supported by a statistically significant improvement on the secondary endpoints like Clinical Global Impression − Severity of illness, Patient Global Impression of Change, and Clinical Global Impression of Change. Samelisant was safe and well tolerated.
Conclusions:
Samelisant could be a potential new therapy for the management of narcolepsy
10.1212/WNL.0000000000208309