Wyeth and Progenics Announce Relistor Receives Canadian Marketing Approval

First-in-world approval of drug to treat opioid induced constipation.

Collegeville, PA, and Tarrytown, NY. – Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE), and Progenics Pharmaceuticals, Inc. (Nasdaq: PGNX), today announced that Wyeth has received marketing approval from Health Canada, the Canadian Regulatory Agency, for RELISTOR™ (methylnaltrexone bromide injection) for subcutaneous use. RELISTOR is indicated for the treatment of opioid-induced constipation (OIC) in patients with advanced illness receiving palliative care. Health Canada’s decision regarding RELISTOR marks the first regulatory approval of this novel medication anywhere in the world.

“Health Canada granted a priority review for RELISTOR, which underscores the important need that exists for an innovative medicine that addresses a serious health condition for which there had been limited medical advancement,” says Joseph S. Camardo, M.D., senior vice president, Global Medical Affairs, Wyeth Pharmaceuticals. “Wyeth and Progenics are pleased to bring RELISTOR to patients as an example of our commitment to discover, develop and deliver important new medicines that work in novel ways to benefit patients who need them.”

RELISTOR is the first approved therapy in a new class of drugs designed to relieve one of the significant side effects of opioids on the gastrointestinal tract without interfering with their ability to provide pain relief. When patient response to laxatives has been insufficient, RELISTOR should be used as an adjunct therapy to induce a prompt bowel movement. Wyeth expects that this product will be launched and available to patients in Canada within approximately 60 days.
“Progenics is proud to share this achievement with the Wyeth team, who have been instrumental in advancing this important new product to market,” said Paul J. Maddon, M.D., Ph.D., Founder, Chief Executive Officer and Chief Science Officer, Progenics Pharmaceuticals, Inc. “We now await a decision from the U.S. Food and Drug Administration by the end of April on RELISTOR. In addition, we and Wyeth continue to work with the European and Australian regulatory authorities to expand the availability of RELISTOR.”

About RELISTOR Subcutaneous Injection

RELISTOR, a peripherally acting mu-opioid receptor antagonist, works by reducing the constipating side effects of opioids, such as morphine and codeine, without affecting their ability to relieve pain. Opioids provide analgesia – or relieve pain – by specifically interacting with mu-opioid receptors within the central nervous system (CNS), the area where pain is perceived – namely, the brain and spinal cord. However, opioids also interact with mu-opioid receptors found outside the CNS, such as those within the gastrointestinal tract, resulting in constipation that can be debilitating. RELISTOR selectively displaces opioids from the mu-opioid receptors outside the CNS, including those located in the gastrointestinal tract. Because of its chemical structure, RELISTOR has restricted access to the CNS.

Important Safety Information for RELISTOR

The Canadian label includes the following safety information:

* RELISTOR is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction or acute surgical abdomen.
* If severe diarrhea occurs during treatment, patients should be advised not to continue therapy with RELISTOR and to consult their physician.
* The adverse reactions with RELISTOR in clinical trials were abdominal pain, flatulence, nausea, dizziness and diarrhea.

About Opioid-Induced Constipation

Many advanced-illness patients are prescribed opioids to manage their pain, and constipation occurs in practically all patients on opioid therapy. The constipation can sometimes be severe enough to limit analgesic opioid use.

About the Subcutaneous RELISTOR Clinical Investigational Program

In March 2007, Progenics submitted a New Drug Application for subcutaneous RELISTOR for the treatment of opioid-induced constipation (OIC) in patients receiving palliative care to the U.S. Food and Drug Administration. This application has a Prescription Drug User Fee Act (PDUFA) date of April 30, 2008. Additionally, in May 2007, Wyeth submitted a Marketing Authorization Application (MAA) in Europe to the European Medicines Agency (EMEA) for subcutaneous RELISTOR. The MAA has been validated, and the EMEA review is expected to occur in 2008. Similarly, in August 2007, Wyeth submitted a marketing application to the Therapeutic Goods Administration division of the Australian government for subcutaneous RELISTOR.