Treatment with the P2X3-receptor antagonist gefapixant for acute cough in induced viral upper respiratory tract infection: A Phase 2a, randomized, placebo-controlled trial

This Phase IIa, randomized, double-blind, parallel-group pilot study evaluated the efficacy of twice-daily gefapixant versus placebo in 46 healthy volunteers inoculated with human rhinovirus 16 to induce upper respiratory tract infection and cough. The primary endpoint was awake cough frequency on Day 3. Secondary endpoints included change from baseline to Day 3 in subjective cough severity measures and cough-specific quality of life, while exploratory endpoints included 24-hour cough frequency on Day 3 and awake cough frequency on Days 1, 2, 4, 5, 6, and 7. Cough frequency was objectively measured using the Vitalograph VitaloJAK cough recording device.