Tercica’s Growth Treatment Increlex Clears FDA With Orphan Drug Exclusivity
This article was originally published in The Pink Sheet Daily
Executive Summary
The company plans to launch the extreme short stature therapy in January with a 30-member sales force.
Tercica will launch the extreme short stature therapy Increlex Jan. 3 following FDA approval Aug. 30. FDA cleared Increlex (mecasermin [rDNA origin] injection) for the orphan indication of "long-term treatment of growth failure in children with severe primary IGF-1 deficiency (primary IGFD) or with growth hormone (GH) gene deletion who have developed neutralizing antibodies to GH." Severe primary IGFD is defined as patients with a height standard deviation score of ?-3.0; basal IGF-1 standard deviation score of ?-3.0; and normal or elevated growth hormone. Tercica will support the launch with a 30-member sales force composed of three groups: clinical science specialists detailing physicians; national account executives educating payors; and regional business directors focusing on building the IGFD market. Physician detailing efforts will initially focus on 400 pediatric endocrinologists in major markets and academic institutions who are likely to be high-volume prescribers, Tercica said. The approval comes despite a citizen petition filed by Insmed Aug. 11 requesting that FDA deny approval of Tercica's mecasermin NDA. Insmed has a pending NDA for SomatoKine (mecasermin rinfabate) to treat growth hormone insensitivity syndrome, an indication encompassed by severe primary IGFD. The Increlex approval could pose a barrier to Insmed's pursuit of orphan exclusivity for SomatoKine; FDA awarded Tercica seven-year orphan exclusivity for Increlex. Tercica said FDA denied Insmed's citizen petition. "What we can say today is that [Increlex] has orphan designation for the approved indication," Tercica CEO Charles Scarlett said during an Aug. 31 investor call. "That means obviously that a same drug for that same indication will be excluded from the market for seven years in the U.S. Of course, the question always becomes 'what is the same drug?' and 'what's the same indication?'" Scarlett emphasized that all questions concerning SomatoKine's orphan status are moot until Insmed's NDA receives approval. "The agency will clarify, I suspect, at that point in time, the exact situation," he said. The SomatoKine user fee date is Oct. 3 (1 (Also see "SomatoKine User Fee Goal Date Extended to Oct. 3, Insmed Says" - Pink Sheet, 10 Jun, 2005.)). FDA said that Insmed's citizen petition "raised not so much legal or procedural issues, but rather issues ordinarily considered and addressed in the review of an application (questions related to the sufficiency of the data to establish safety and efficacy for the intended use)." "After FDA fully considered the NDA for Increlex, we found that the data provided were sufficient for approval," the agency said. Insmed's petition claimed that the Increlex NDA contained insufficient data and did not fully address potential safety problems, particularly regarding risks of hypoglycemia. In a pooled analysis of five clinical trials, hypoglycemia appeared in 42% of patients, Increlex labeling states. The hypoglycemia concerns, however, do not appear to have weighed too heavily on FDA; Increlex labeling includes a precaution for "insulin-like hypoglycemic" effects. FDA may not have been as concerned by the hypoglycemia data because of a high background incidence in the patient population and the fact that no patients dropped out of the studies due to hypoglycemia, Tercica maintained. The Increlex NDA was approved under six-month priority review, one day ahead of the application's Aug. 31 user fee date. - Andrew Kasper |