Dual Phosphodiesterase 3 and 4 Inhibitor Ensifentrine Reduces Exacerbation Rate and Risk in Patients with Moderate-to-Severe Chronic Obstructive Pulmonary Disease

Introduction Exacerbations in chronic obstructive pulmonary disease (COPD) can be life-threatening and lead to irreversible declines in lung function and quality of life. Medications that reduce exacerbation burden are an unmet need, as exacerbations put patients at risk for more exacerbations and decrease quality of life. Ensifentrine is a novel, first-in-class, selective, dual inhibitor of phosphodiesterase 3/4 with demonstrated nonsteroidal anti-inflammatory activity and bronchodilatory effects. Research Question Does ensifentrine reduce the rate and/or risk of COPD exacerbations? Study Design and Methods A prespecified, pooled analysis of the phase 3 clinical trials ENHANCE-1 (NCT04535986) and ENHANCE-2 (NCT04542057) was conducted to assess the effect of ensifentrine on exacerbation rate and risk (time to first exacerbation). The trials included symptomatic patients aged 40-80 years with moderate-to-severe COPD who received 3 mg twice-daily ensifentrine over 24 weeks or placebo. Subgroup analyses and frequent exacerbator transition risk were conducted post-hoc. Results In total, 975 ensifentrine-treated and 574 placebo-treated patients were included in the pooled analysis, including 62% on concomitant LAMA or LABA therapy and 18% on concomitant inhaled corticosteroid therapy. Ensifentrine was associated with significant reductions in the rate (rate ratio, 0.59; 95% CI, 0.43-0.80; P < 0.001) and risk (hazard ratio, 0.59; 95% CI, 0.44-0.81; P < 0.001) of moderate/severe exacerbations compared with placebo. Reductions in the rate and risk of exacerbations were generally consistent across patient subgroups, including age, sex, race, background maintenance medication use, chronic bronchitis, eosinophil count, COPD severity, and exacerbation history. Ensifentrine was associated with a numerical delay in transitioning from an infrequent exacerbator (GOLD B) to a frequent exacerbator (GOLD E) compared with placebo. Conclusion Ensifentrine reduced the rate of exacerbations and increased the time to first exacerbation among patients with COPD across a broad range of clinically relevant subgroups.