Wyeth Pharmaceuticals / Progenics Pharmaceuticals, Inc.

Opioid-Induced Constipation (OIC)

Disease Overview

Opioid-induced constipation (OIC) results from opioid binding to mu-receptors in the GI tract, slowing peristalsis and reducing fluid secretion. Patients on chronic opioids — particularly advanced-illness palliative care, post-surgical, and chronic non-cancer pain populations — frequently must reduce analgesic dosing because of debilitating constipation, creating a treatment dilemma between pain relief and bowel function.

Competitive Landscape

In 2005, no peripherally-acting mu-opioid receptor antagonist (PAMORA) was approved; clinicians relied on stool softeners, osmotic laxatives, and stimulants that failed to address the underlying receptor-mediated mechanism. Methylnaltrexone (later Relistor) — invented by University of Chicago's Dr. Leon Goldberg and developed by Dr. Jonathan Moss — was the first-in-class PAMORA. Dr. Moss told the University of Chicago, 'It took almost 30 years but it finally seems that a very useful drug will at last become an option for those who desperately need it'. The Wyeth-Progenics partnership (announced December 23, 2005, valued up to $356.5M) targeted three formulations: subcutaneous (advanced illness, NDA early 2007), intravenous (postoperative ileus, NDA late 2007), and oral (chronic pain, NDA late 2008). Subsequent competition emerged from Salix's Movantik (naloxegol, AstraZeneca/Daiichi Sankyo, approved 2014) and Shionogi's Symproic (naldemedine, 2017). Forward-looking close: The 2005 collaboration unraveled — the IV postoperative ileus Phase 3 failed, Wyeth was acquired by Pfizer in 2009, and Wyeth returned global rights to Progenics in October 2009 for a $10M payment. Relistor was eventually acquired by Salix (2011) and then Bausch Health (2015), where it remains a modest niche brand against generic naloxegol.