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Introduction and Objectives Cough patient-reported outcomes (PROs) used in gefapixant clinical trials may not be widely understood or used in clinical practice. The Patient Global Impression of Change (PGIC) PRO may be more intuitive and relevant to physicians. Here, we use prespecified PGIC responder analyses and post hoc analyses to assess the relationship between clinically meaningful responses as defined by cough PROs vs PGIC in two phase 3 trials (COUGH-1/-2 [ NCT03449134, NCT03449147]).Methods COUGH-1/-2 methods have previously been reported (McGarvey et al. Lancet. 2022;399:909–923). In prespecified analyses, PGIC responder rates were compared between gefapixant 45 mg twice daily and placebo. Post hoc analyses assessed the relationship between PGIC responders (ie, very much improved or much improved) and cough PRO responders pooled across both treatment groups and both trials.Results PGIC responder rates in COUGH-1/-2 were higher for gefapixant vs placebo; the 95% CIs for treatment differences excluded 0. Across treatment groups/trials, there was strong agreement between PGIC and cough PRO responses ( figure 1).Abstract P117 Figure 1(A) PGIC categories and responder definitions. (B) Proportions of PGIC responders (gefapixant 45 mg BID vs placebo) and treatment difference. (C) Agreement between PGIC and cough PROs for responders. (D) Agreement between PGIC and cough PROs for nonresponders. LCQ response was defined as ≥1.3-point increase. CSD response was defined as ≥1.3-point decrease. VAS response was defined as ≥30-mm decrease. Nonresponse to LCQ, CSD, and VAS was defined as not meeting responder criteria. an=PGIC responder, and N=number of participants with data after nonresponder imputation at the time point. BID, twice daily; CSD, Cough Severity Diary; LCQ, Leicester Cough Questionnaire; PGIC, Patient Global Impression of Change; PRO, patient-reported outcome; VAS, visual analog scaleConclusions In COUGH-1/-2, there were more PGIC responders in the gefapixant vs placebo group. The relationship between responses on the PGIC and cough PROs suggests cough PRO responses reported in COUGH-1/-2 are similar to the observed results of the PGIC, an endpoint that may be more easily interpreted in clinical practice.