Gefapixant significantly decreased cough frequency in unexplained chronic cough study

US pharma giant Merck & Co (NYSE: MRK), known as MSD outside f the USA and Canada, has announced the results from two pivotal Phase III trials (COUGH-1 and COUGH-2) evaluating the efficacy and safety of gefapixant (MK-7264), an investigational, orally administered, selective P2X3 receptor antagonist, for the potential treatment of refractory or unexplained chronic cough.

In these studies, adult patients treated with gefapixant 45mg twice daily demonstrated a statistically-significant reduction in 24-hour cough frequency (measured objectively, as coughs per hour, using 24-hour sound recordings) versus placebo at 12 weeks (COUGH-1) (18.45% reduction relative to placebo, 95% CI [-32.92, -0.86; p=0.041]) and 24 weeks (COUGH-2) (14.64% reduction relative to placebo, 95% CI [-26.07, -1.43; p=0.031]).

Chronic cough is a persistent cough that lasts for more than eight weeks in adults. Far from being “a simple cough,” this condition negatively impacts the mental, physical and social aspects of a patient’s life, the company explained.