Conclusions
cough, taste disturbances, Cough
Sivopixant did not demonstrate a statistically significant difference vs placebo in change from baseline in 24-h cough frequency. Sivopixant 300 mg was well tolerated and demonstrated greater reductions in hourly cough counts over 24 h than lower doses tested or placebo, although no significant differences were observed across groups. Therefore, efficacy has not been confirmed. Cough frequency at baseline (< or ≥ 10 coughs/h) and its consistency from the screening period may be factors impacting the ability to show treatment efficacy. Cough severity (VAS), LCQ total score, and PGIC showed significant improvement in responses with sivopixant 300 mg vs placebo. A well-tolerated safety profile with mild-to-moderate reversible taste disturbances was reported. This study lays the foundation for further evaluation of sivopixant 300 mg in future RCTs, with protocol planning informed by this phase 2b study, including measures to reduce the placebo effect.