Study Evaluating the Efficacy and Safety of Subcutaneous Methylnaltrexone (MOA-728) for the Treatment of Opioid-Induced-Constipation

A Multicenter, Randomized, Double-Blind, Placebo-Controlled, And Parallel-Group Study Of Subcutaneous Methylnaltrexone (MOA-728) For The Treatment Of Opioid-Induced Constipation In Adult Subjects

The primary purpose of this study is to evaluate the safety, efficacy, and tolerability of subcutaneous (injection beneath the skin) MOA-728 versus placebo in adult Asian subjects with opioid-induced constipation associated with advanced illness (ie, a terminal illness such as incurable cancer or other end-stage disease) or chronic nonmalignant pain.

Subjects received subcutaneous methylnaltrexone (also referred to as MOA-728 or MNTX) or placebo every other day beginning on Day 1 up to a maximum of 7 doses during the 2-week double-blind period.

Inclusion criteria for this study included subjects with advanced illness or subjects with chronic nonmalignant pain. The actual study population included only subjects with cancer-related advanced illness.

All subjects who completed the double-blind treatment phase of this study could elect to receive methylnaltrexone during a 12-week open-label extension study, provided eligibility criteria were met. Subjects who did not continue in the open-label extension study had a follow-up visit 2 weeks after their last dose of test article.

Inclusion Criteria:

• Men and women who are at least 18 years of age, and who have a diagnosis of advanced illness with anticipated life expectancy >= 1 month;
• Is receiving a regular dose of opioids for the control of pain;
• Has a diagnosis of opioid induced constipation;
• Is on a stable laxative regimen.

Exclusion Criteria:

• Has a known or suspected mechanical gastrointestinal obstruction, or any potential non-opioid cause of bowel dysfunction contributed to constipation;
• Has evidence of current fecal impaction;
• Has evidence of active diverticulitis, or peritonitis, or a history of bowel surgery within 30 days before test article administration;
• Has a body weight less than 27 kg
• Has any major illness/condition that, in the investigator's judgment, will substantially increase the risk associated with the subject's participation in and completion of the study, or could preclude the evaluation of the subject's response.