Conditions: Opioid-induced Constipation
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 37
Healthy volunteers: no

Brief summary:
The purpose of this study is to examine the safety and activity of MNTX in relieving opioid-induced constipation following orthopedic procedures.

Detailed description:
This is a double-blind, randomized, parallel-group, placebo- controlled Phase 2 study to evaluate the safety and activity of subcutaneous (SC) MNTX versus SC placebo in participants who have undergone orthopedic procedures and who are expected to require opioids for 1 week after randomization. Participants will sign an informed consent form and be screened between Days 4-10 after their orthopedic procedure. Those participants who meet all eligibility requirements will be enrolled in the study. Treatment with study medication will be continued until either the participant no longer requires opioid medication for pain relief or the maximum number of doses is reached. Originally, participants were receiving treatment for up to 7 days. Then after Protocol Amendment 1 (12 March 2008), the duration of treatment changed from "up to 7 days" to "up to 4 days".

Arms:
arm 1: Participants will receive methylnaltrexone (MNTX) 12 milligrams (mg) subcutaneously (SC) once daily for up to 4 or 7 days, depending upon the protocol version under which each participant is enrolled. arm 2: Participants will receive placebo matching to MNTX SC once daily for up to 4 or 7 days, depending upon the protocol version under which each participant is enrolled.

Interventions: intervention 1: Methylnaltrexone bromide intervention 2: Placebo
Intervention descriptions: intervention 1: Methylnaltrexone will be administered as per the dose and schedule specified in the respective arm. intervention 2: Placebo matching to methylnaltrexone will be administered as per the dose and schedule specified in the respective arm.

Protocol document: