methylnaltrexone and Flatulence

Methylnaltrexone is a peripheral opioid receptor antagonist undergoing phase III clinical trials for the treatment of opioid-induced constipation in patients with advanced medical illness who are being treated with narcotics for pain. The compound does not cross the blood-brain barrier in humans and reverses the opioid effects without interfering with pain relief. Some opioid-induced adverse events that the drug may potentially target include constipation, nausea/vomiting, cough suppression and urinary retention. Methylnaltrexone was discovered by researchers at the University of Chicago, Chicago, Illinois, USA and is in joint development with Progenics Pharmaceuticals and Wyeth Pharmaceuticals. Progenics is conducting clinical trials with three methylnaltrexone dosage forms: subcutaneous, IV and oral. Progenics plans to complete the clinical development of methylnaltrexone alone, after which potential pharmaceutical or biotechnology partners will be looked at to provide financial support and marketing expertise, particularly outside the US market. In December 2005, Progenics and Wyeth Pharmaceutical (Wyeth) entered into an exclusive, worldwide agreement for the joint development and commercialisation of methylnaltrexone for the treatment of opioid-induced side effects, including constipation and postoperative bowel dysfunction. Under the terms of the licensing agreement, Wyeth has worldwide rights to the compound and Progenics retains the option to co-promote methylnaltrexone in the US. The companies will collaborate on the worldwide development of methylnaltrexone. Under the terms of the agreement, Wyeth has made an up-front payment to Progenics and will also make additional milestone payments. Wyeth will also pay Progenics royalties on worldwide sales, and co-promotion fees within the US. Wyeth is also responsible for all future development and commercialisation costs. Wyeth will develop oral methylnaltrexone worldwide. Progenics will lead the US development of subcutaneous and intravenous methylnaltrexone, while Wyeth will lead development of these parenteral products outside the US.UR Labs licensed methylnaltrexone from the University of Chicago. In October 2001, Progenics in-licensed the methynaltrexone patent portfolio in exchange for rights to future methynaltrexone royalties. In December 2005, Progenics acquired a substantial portion of the royalty and milestone payments in exchange for 686,000 shares of Progenic's common stock and 2.6 million US

Topics: Clinical Trials as Topic; Colic; Constipation; Flatulence; Humans; Injections, Intravenous; Naltrexone; Narcotic Antagonists; Quaternary Ammonium Compounds; Treatment Outcome