Wyeth Pharmaceuticals and Progenics Pharmaceuticals will begin clinical testing of a new formulation of oral methylnaltrexone for the treatment of opioid-induced constipation. Preliminary results from the Phase II trial, conducted by Wyeth, showed that the initial formulation of oral methylnaltrexone was generally well tolerated but did not show sufficient clinical activity to advance into Phase III testing. If the new formulation is successful, the companies plan to file an NDA for oral methyln...