NPS wraps another positive PhIII study as parathyroid drug impresses

A week after giving investors a Halloween scare with the news of two cancer deaths in a critical trial of Gattex, NPS Pharmaceuticals ($NPSP) followed up with positive top-line results from a pivotal study for NPSP558 as a treatment for a rare endocrine disorder. Investors cheered the news with a 10% surge in the biotech's share price as NPS laid plans for a second near-term NDA.

NPS has already nailed down orphan status for the treatment of hypoparathyroidism, in which patients suffer from an insufficient level of a principal regulator of calcium and phosphorus. In the study 53% of patients treated with NPSP558 hit the primary endpoint--"50% or greater reduction in oral calcium supplementation and active vitamin D therapy and a total serum calcium concentration that was normalized or maintained compared to baseline after 24 weeks of treatment"--versus 2% of patients in the placebo arm.

"These positive results from our Phase III REPLACE study are an important milestone and bring us one step closer to our goal of providing hypoparathyroidism patients with a much-needed replacement therapy," said Dr. Francois Nader, president and chief executive officer of NPS Pharmaceuticals. "Based on these results we expect to file for FDA approval of NPSP558 in 2012."

NPS shares plunged 33% on October 31 after investigators reported the deaths of two out of three new cancer cases discovered among the patients enrolled in a study of Gattex for short bowel syndrome. But investigators shrugged off the tiny cluster of cancer victims, noting that it included two lung cancer victims with a history of smoking and that one of the tumors appeared only 85 days after the trial launched. The study was positive in demonstrating a reduced need for nutritional support and NPS outlined plans to file for approval before the end of this year.

The Street notes that Stifel Nicolaus analyst Maged Shenouda has pegged potential sales of NPSP558 at $131 million in 2015.

- here's the press release
- get the story from TheStreet