Opioid-induced constipation is common and debilitating.
Dr William Chey and colleagues investigated the efficacy and safety of naloxegol, an oral, peripherally acting, μ-opioid receptor antagonist, for the treatment of opioid-induced constipation.
In 2 identical phase 3, double-blind studies, outpatients with noncancer pain and opioid-induced constipation were randomly assigned to receive a daily dose of 12.5 or 25 mg of naloxegol or placebo.
The primary end point was the 12-week response rate in the intention-to-treat population.
|Response rates were significantly higher with 25 mg of naloxegol |
|New England Journal of Medicine|
The key secondary end points were the response rate in the subpopulation of patients with an inadequate response to laxatives before enrollment, time to first postdose spontaneous bowel movement, and mean number of days per week with one or more spontaneous bowel movements.
The research team found that response rates were significantly higher with 25 mg of naloxegol than with placebo.
The team observed a shorter time to the first postdose spontaneous bowel movement, and a higher mean number of days per week with one or more spontaneous bowel movements with 25 mg of naloxegol versus placebo in both studies, and with 12.5 mg of naloxegol in study 04.
The team noted that pain scores and daily opioid dose were similar among the 3 groups.
Adverse events, primarily gastrointestinal, occurred most frequently in the groups treated with 25 mg of naloxegol.
Dr chey's team commented, "Treatment with naloxegol, as compared with placebo, resulted in a significantly higher rate of treatment response, without reducing opioid-mediated analgesia."