Progenics and Wyeth have announced Phase III clinical trial results for methylnaltrexone. The results are from the second pivotal Phase III trial of the subcutaneous form of the investigational drug methylnaltrexone for the treatment of opioid-induced constipation in patients with advanced illnesses, such as cancer and cardiovascular disease.

Results showed that nearly half of constipated patients with advanced illness experienced laxation within four hours of receiving their first dose of methylnaltrexone, and more than 70 percent responded by the end of the first week of treatment. For those who responded, the median time to laxation following methylnaltrexone treatment was 30 minutes, and there were no reports of diminished analgesia due to study medication.