FDA will review Salix's application for its drug Relistor

Salix Pharmaceuticals announced this morning that the Food and Drug Administration will review its application to expand the allowed uses for Relistor, a drug that treats constipation in patients taking pain medicines.

Salix and its partner, Progenics Pharmaceuticals, are seeking to have Relistor approved to treat patients with chronic pain.

The injected drug is currently only approved to treat patients with advanced illnesses who are taking opioid painkillers, which often cause severe constipation.

The FDA will rule on the application on April 27.

Raleigh-based Salix purchased the rights to Relistor in February.

The drug had just $16 million in worldwide sales last year, but Salix thinks the drug has the potential for peak annual sales of a billion dollars.

The deal with Progenics, based in Tarrytown, N.Y., called for Salix to pay $60 million up front and payments worth up to $290 million more if the drug meets development and sales milestones.

In addition to seeking approval to use Relistor to treat those with chronic, nonmalignant pain, Salix also plans to seek approval for an oral version of the drug.

Raleigh-bsed Salix sells drugs to treat gastrointestinal ailments. The company's best-selling drug, Xifaxan, is approved to treat traveler's diarrhea and a rare liver condition.

In March, the FDA informed Salix that is application seeking to get Xifaxan approved for irritable bowel syndrome was not ready for approval.

Salix officials met with the agency in June to discuss the ruling, and CEO Carolyn Logan said earlier this month that the company would continue to seek IBS approval, a market that could be worth billions.

When it purchased Relistor, Salix officials said the company would promote the drug among the network of gastroenterologists who are familiar with Salix's other products.

Salix shares closed at $29.88 on Monday. The stock is down 21 percent over the last year.