NPS Pharma ($NPSP) picked up FDA approval for the rare disease-treating Natpara, capping a lengthy review process and supporting Shire's ($SHPG) decision to spend $5.2 billion on the company.
The injected drug works by replacing human parathyroid hormone 1-84, which is underproduced in patients with the rare endocrine disorder hypoparathyroidism. Low levels of the hormone lead to calcium deficiency and difficulty converting Vitamin D, spurring complications including paresthesia, muscle pain, bone-density issues and, in acute cases, cardiac arrhythmias, the company said.
Natpara had an up-and-down trip through the regulatory process, with the FDA extending its review by three months to pore over the drug's pivotal data. Agency staff took issue with the biomarkers used to establish Natpara's clinical efficacy, also flagging preclinical studies in which rats taking the drug developed bone cancer. Last year, a panel of agency advisers voted 8-5 in favor of its approval, but not without expressing concerns that the drug led to no meaningful improvements in bone mineral density and failed to beat placebo in reducing patients' urinary calcium.
But the U.S.'s roughly 60,000 hypoparathyroidism sufferers have few other options, the FDA said, and NPS's drug proved itself effective in boosting calcium levels for patients unresponsive to other treatments. Natpara will carry a label warning of blood cancer risks and recommending it only for patients whose low calcium cannot be controlled with supplements.
The approval is good news for Shire and its efforts to expand in the rare disease world. The U.K. drugmaker expects to close its acquisition of NPS this quarter, a high-dollar fueled by big expectations for Gattex, an approved treatment, and the potential of Natpara.
|Shire CEO Flemming Ornskov|
"The Natpara label is in line with our expectations, and we believe this approval further validates Shire's decision to acquire NPS Pharma, which is an excellent strategic fit allowing us to leverage our market expertise, core capabilities in rare disease patient management, and global footprint," Shire CEO Flemming Ornskov said in a statement.
The drug, which NPS plans to launch next quarter, is expected to bring in about $500 million a year at its peak.
- read the FDA's release
- here's Shire's statement