The US FDA has approved Tercica, Inc's Increlex (mecasermin (rDNA origin) injection) for the 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 growth hormone. The FDA also designated Increlex as an orphan drug for severe Primary IGFD.

Insulin-like growth factor-1, or IGF-1, is the direct mediator of growth hormone's effect on statural growth and must be present in order for children's bones, cartilage, and organs to grow normally. Severe Primary IGFD is a growth hormone-resistant state characterized by abnormally low blood IGF-1 levels in the presence of normal or elevated growth hormone, which afflicts approximately 6,000 children in the US.

John A. Scarlett, president and CEO of Tercica said, "Today, Increlex becomes Tercica's first commercial drug and represents the first major innovation in the treatment of short stature since recombinant growth hormone was approved 20 years ago -an advance that we believe will change the way physicians diagnose and treat patients with growth failure due to severe Primary IGFD."

The active ingredient of Increlex is identical to the natural hormone, IGF-1, which the body produces in response to stimulation by growth hormone. Without adequate IGF-1, children cannot achieve height within the normal range. Tercica acquired exclusive rights to develop, commercialize and manufacture Increlex from Genentech, Inc.

Children with severe Primary IGFD have height and serum IGF-1 levels that are more than three standard deviations below normal. They are not growth hormone deficient, and, because they are resistant to the effects of growth hormone, they cannot be expected to respond adequately to growth hormone therapy. In both children and adults, severe Primary IGFD can lead to a range of other metabolic disorders including lipid abnormalities, decreased bone density, obesity and insulin resistance.