Gefapixant leads to modest improvements in cough

For adults with refractory or unexplained chronic cough, gefapixant leads to modest improvement in cough frequency, severity, and quality of life, according to a review published online Sept. 11 in the Journal of the American Medical Association to coincide with the European Respiratory Society International Congress 2023, held from Sept. 9 to 13 in Milan.

Elena Kim, from McMaster University in Hamilton, Ontario, Canada, and colleagues examined the efficacy and tolerability of gefapixant for treatment of adults with refractory or unexplained chronic cough in a systematic review of parallel and crossover randomized clinical trials (RCTs) that compared gefapixant with placebo or two or more doses of gefapixant with or without placebo. The primary analysis included nine RCTs with 2,980 patients.

The researchers found that gefapixant (45 mg twice daily) had small effects on awake cough frequency (17.6 percent reduction), cough severity (mean difference, −6.2 on 100-mm visual analog scale), and cough-specific quality of life (mean difference, 1.0 point on the Leicester Cough Questionnaire) compared with placebo. However, an important increase in treatment-related adverse events (32 more per 100 patients) and taste-related adverse events (32 more per 100 patients) was probably caused by gefapixant versus placebo. Small effects on taste-related adverse events were suggested for gefapixant (15 mg) versus placebo based on high-certainty evidence.

"Although gefapixant did appear to have a small effect on improving cough compared with placebo, the effects were marginal when compared with the large, favorable effects of placebo alone," Richard S. Irwin, M.D., and J. Mark Madison, M.D., from the University of Massachusetts Chan Medical School in Worcester, write in an accompanying editorial.

Several authors disclosed ties to pharmaceutical companies, including Merck, the manufacturer of gefapixant.

Copyright © 2023 HealthDay. All rights reserved.