Safety and efficacy of gefapixant, a novel drug for the treatment of chronic cough: A systematic review and meta-analysis of randomized controlled trials.

AIM

We conducted this systematic review and meta-analysis to investigate the efficacy and safety of gefapixant, a novel P2X3 receptor antagonist, in patients with chronic cough.

METHODS

We searched four databases for randomized controlled trials (RCTs). We assessed the cough frequency, severity, total Leicester cough questionnaire (LCQ) score, and adverse events. We analyzed the data using Open Meta-Analyst and Review Manager Software.

RESULTS

We included four unique studies (comprising five stand-alone RCTs) with 439 patients. Compared to placebo, gefapixant had positive anti-tussive effects by improving awake cough frequency (mean difference [MD] = -5.27, 95% confidence interval [CI] [-6.12, -4.42], < 0.00001), night cough frequency (MD = -3.71, 95% CI [-6.57, -0.85], = 0. 01), 24 h cough frequency (MD = -4.18, 95% CI [-5.01, -3.36], < 0.00001), cough severity using the Visual Analog Scale (MD = -13.36, 95% CI [-17.80, -8.92], < 0.00001), cough severity diary (MD = -0.88, 95% CI [-1.25, -0.51], < 0.00001), and total LCQ score (MD = 2.00, 95% CI [1.15, 2.86], = 0. 00001). Meta-regression analyses showed a positive correlation between the gefapixant dose and the incidence of any adverse event (relative risk [RR] = 0.239, 95% CI [0.093, 1.839], = 0.001) and incidence of adverse event related to treatment (RR = 0.520, 95% CI [0.117, 0.922], = 0.011).

CONCLUSIONS

In patient with chronic cough, gefapixant exhibits favorable anti-tussive outcomes by improving the cough frequency, severity, and quality of life. While gefapixant is largely tolerable, its side effects (notably taste alteration) are dose dependent.