An experimental pill from Merck reduced the frequency of chronic coughing enough to achieve the goal of two Phase 3 clinical trials, but the benefit relative to placebo was small and a majority of patients reported negative alterations to their sense of taste.
Merck presented detailed study results of its chronic cough drug gefapixant for the first time on Monday at the annual meeting of the European Respiratory Society. This followed its announcement last March that the Phase 3 studies achieved their primary endpoints.
The mixed data — underwhelming efficacy coupled with a high rate of side effects and patient discontinuations — raise questions about gefapixant’s future prospects and leave room for competitors developing similar chronic cough drugs to overtake it. Merck is expected to submit gefapixant for approval later this year, while rivals, which include Bayer, Shionogi, and Bellus Health, have not yet started late-stage clinical trials. In July, Bellus’ chronic cough drug failed a mid-stage clinical trial.