A Randomized, Placebo-Controlled Trial of Lubiprostone for Opioid-Induced Constipation in Chronic Noncancer Pain

OBJECTIVES: This multicenter, phase 3 trial evaluated oral lubiprostone for constipation associated with non-methadone opioids in patients with chronic noncancer-related pain. METHODS: Adults with opioid-induced constipation (OIC; <3 spontaneous bowel movements [SBMs] per week) were randomized 1: 1 to double-blind lubiprostone 24 mu g or placebo twice daily for 12 weeks. The primary end point was the overall SBM response rate. Responders had at least moderate response (>= 1 SBM improvement over baseline frequency) in all treatment weeks with available observed data, as well as full response (>= 3 SBMs per week) for at least 9 of the 12 treatment weeks. RESULTS: In total, 431 patients were randomized; 212 each received lubiprostone and placebo, and 7 were not treated. Overall, the SBM response rate was signifi cantly higher for patients treated with lubiprostone vs. placebo (27.1 vs. 18.9%, respectively; P=0.030). Overall mean change from baseline in SBM frequency was signifi cantly greater with lubiprostone vs. placebo (3.2 vs. 2.4, respectively; P=0.001). The median time to fi rst SBM was signifi cantly shorter with lubiprostone vs. placebo (23.5 vs. 37.7 h, respectively; P = 0.004). Compared with placebo, the patients treated with lubiprostone exhibited signifi cant improvements in straining (P=0.004), stool consistency (P<0.001), and constipation severity (P = 0.010). No signifi cant differences were observed in quality-of-life measures or the use of rescue medication; however, the percentage of patients who used rescue medication was consistently lower in the lubiprostone group than in the placebo group at months 1 (34.9 vs. 37.7%), 2 (23.4 vs. 26.6%), and 3 (20.5 vs. 22.0%). Adverse events (AEs) >5% were diarrhea, nausea, vomiting, and abdominal pain (lubiprostone: 11.3, 9.9, 4.2, and 7.1%, respectively; placebo, 3.8, 4.7, 5.2, and 0%, respectively). None of the serious AEs (lubiprostone, 3.3%; placebo, 2.8%) were related to lubiprostone. CONCLUSIONS: Lubiprostone signifi cantly improved symptoms of OIC and was well tolerated in patients with chronic noncancer pain.