Methylnaltrexone: relieving opioid-induced constipation

The investigational compound methylnaltrexone is effective for the treatment of opioid-induced constipation in patients with advanced illnesses, according to results of the MNTX 302 trial presented at Digestive Disease Week (DDW) 2006 [Los Angeles, California, US; May 2006]. Results from the second pivotal phase III trial of the SC form of this investigational agent showed significant benefits for methylnaltrexone over placebo; nearly 50% of patients treated with methylnaltrexone had a bowel movement within 4 hours of receiving their first dose, and more than 70% had a laxation response within 4 hours of receiving at least one of the first four doses of methylnaltrexone. For those patients who responded, the median time to laxation was 30 minutes.