Influence of Demographic Factors on Clinical Outcomes in Adults with Chronic Idiopathic Constipation Treated with Plecanatide

INTRODUCTION: Chronic idiopathic constipation (CIC) is a common condition that affects some patient groups more often. Demographic/clinical characteristics can differ in presentation and therapeutic response. The impact of these characteristics on plecanatide efficacy/safety was examined. METHODS: Data from 2 identically designed, randomized, phase 3 trials of adults with CIC receiving plecanatide 3 mg, 6 mg, or placebo for 12 weeks were analyzed. Subgroups were baseline age, body mass index (BMI), race/ethnicity, and sex/gender. Endpoints included durable overall complete spontaneous bowel movement (CSBM) responder rate, weekly CSBMs and spontaneous bowel movements (SBMs), and adverse events. RESULTS: Overall (n = 2639; plecanatide 3 mg [n = 877]; plecanatide 6 mg [n = 877]; placebo [n = 885]), CSBM responder rates were significantly greater with plecanatide 3 mg and 6 mg versus placebo in subgroups aged <65 years (P < 0.001), females (P < 0.001), whites (P < 0.001), and BMI <25 kg/m² (P ≤ 0.004) and 25–30 kg/m² (P < 0.001); as well, for 3 mg: ≥65 years (P = 0.03), non-whites (P < 0.001), and BMI ≥30 kg/m² (P = 0.02). Improvement from baseline in weekly CSBM and SBM frequency occurred in all subgroups for both plecanatide doses versus placebo (P ≤0.02) at week 12, except aged ≥65 years for plecanatide 6 mg. The most common adverse event was diarrhea (3 mg [4.9%]; 6 mg [5.4%]; placebo [1.3%]). DISCUSSION: Pooled data from identically designed CIC trials strengthened the ability to identify meaningful subgroup comparisons regarding plecanatide efficacy and safety.