COLLEGEVILLE, Pa. & TARRYTOWN, N.Y.--(BUSINESS WIRE)--Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE) and Progenics Pharmaceuticals, Inc. (Nasdaq: PGNX) today announced plans to initiate two, four-week phase 2 clinical trials to evaluate daily dosing of oral methylnaltrexone in patients with chronic, non-malignant pain who are being treated with opioids and are experiencing opioid-induced constipation (OIC).