Progenics Pharmaceuticals, Inc. and Salix Pharmaceuticals, Ltd. recently announced they have entered into an exclusive worldwide (except Japan) agreement by which Salix has licensed rights to RELISTOR® (methylnaltrexone bromide). RELISTOR Subcutaneous Injection is indicated for the treatment of opioid-induced constipation (OIC) in patients with advanced illness who are receiving palliative care, when response to laxative therapy has not been sufficient. Use of RELISTOR beyond 4 months has not been studied.
RELISTOR is a peripherally acting mu-opioid receptor antagonist that counteracts the constipating effects of opioid pain medications in the gastrointestinal tract without affecting their ability to relieve pain. The methylnaltrexone license includes intellectual property from the University of Chicago, Progenics Pharmaceuticals, and Wyeth Pharmaceuticals, including patents and applications with expiration dates that will range from 2017 through 2031. RELISTOR was approved in the US in 2008, and currently, the drug is approved for use in over 50 countries worldwide. In 2010, RELISTOR single-use, prefilled syringes were approved for use in the US, Canada, and the European Union. Worldwide net sales of RELISTOR totaled $16 million in 2010.
Financial terms of the transaction include a $60 million up-front payment and development milestones totaling $90 million, contingent upon the achievement of certain US regulatory milestones. Salix also will pay sales-based milestones of up to $200 million plus royalties on product sales in the US, as well as 60% of all revenue received from non-US sublicensees. Salix will fund all development, registration, and commercialization activities for RELISTOR in markets worldwide other than in Japan, where Progenics has licensed to Ono Pharmaceuticals the rights to develop and commercialize subcutaneous RELISTOR.
Salix will market RELISTOR directly through its specialty sales force in the US, and outside the US, RELISTOR will be marketed with sublicenses to regional companies. The parties plan an April 2011 transition of RELISTOR commercial and development responsibility to Salix from Pfizer Inc, which acquired Progenics’ former RELISTOR partner, Wyeth Pharmaceuticals. While Salix effects a country-by-country transition of ex-US commercialization rights, Wyeth will remain the Marketing Authorization Holder for RELISTOR and will continue to supply product. In the interim, Wyeth remains responsible for all manufacturing, clinical, medical, and regulatory activities for RELISTOR outside of the US and Japan.
