Aims:? The Leicester Cough Questionnaire (LCQ) captures the impact of Refractory Chronic Cough (RCC) on patient quality of life across physical, psychological, and social subdomains. We report the improvements in quality of life observed in LCQ subdomains in SOOTHE (NCT04678206), a phase 2b trial of camlipixant (BLU-5937) in participants diagnosed with RCC.

Methods:?Participants (n=249) who maintained a baseline awake cough frequency ?25 coughs/h were randomized in the main population, 1:1:1:1 to the three active treatment arms of camlipixant (12.5, 50 and 200 mg BID) or placebo. The primary efficacy endpoint was the change from baseline of the log-transformed 24H cough frequency, and the secondary endpoint of impact of cough on quality of life was assessed using the LCQ.

Results: Concomitant with reductions in objective cough frequency, participants treated with camlipixant experienced improvements in LCQ total score over 29 days. Consistent improvements were observed in all three LCQ subdomains. At day 29, participants treated with 12.5, 50 and 200 mg BID or placebo, respectively, demonstrated improvements from baseline of 0.7(0.1)*, 0.5(0.1), 0.9(0.1)* and 0.3(0.1) points to the LCQ physical subdomain, 0.9(0.2), 0.7(0.2), 1.1(0.2)* and 0.4(0.2) points to the LCQ psychological subdomain and 1.0(0.2)*, 0.9(0.2), 1.4(0.2)* and 0.5(0.2) points to the LCQ social subdomain (*p-value of difference over placebo ?0.05).

Conclusions: Improvements in cough-related quality of life over 29 days of treatment with camlipixant in SOOTHE were supported by consistent improvements in all three LCQ subdomains.