West Coast Editor

Insmed Inc. submitted its new drug application for SomatoKine to the FDA, disclosing the move days after letting investors know about a patent-infringement lawsuit related to the product that was filed by Tercica Inc. and licensor Genentech Inc.

Insmed's stock (NASDAQ:INSM) dipped 9 cents Tuesday to close at $2.21.

Richmond, Va.-based Insmed's SomatoKine, for growth hormone-insensitivity syndrome, is an IGF-1 therapy composed of recombinant human IGF-I and IGF-binding protein-3 (IGF-1/IGFBP-3 complex).

SomatoKine has won orphan drug designation for the indication, characterized by genetic and acquired conditions in which the action of growth hormone is absent or attenuated, resulting in low blood levels of IGF-1, the primary mediator in growth hormone's functioning - that is, the one that allows children to use their hormone and grow.

South San Francisco-based Tercica reported positive Phase III data in June on its lead rhIGF-1 for short people. The drug was evaluated in 65 children with IGF-1 deficiency. Results showed patients on therapy enjoyed a threefold increase in the rate of growth in the first year, and a twofold increase in growth rate over the entire eight years. Tercica is aiming to file an NDA this quarter. (See BioWorld Today, June 22, 2004.)

Tercica also sued Insmed and its contract manufacturer, Avecia Ltd., of Billingham, UK, overseas last week. Insmed's CEO, Geoffrey Allan, said Tercica's "allegations are without merit and [we] intend to vigorously defend our position and right to make SomatoKine."

Neither side wanted to talk about the litigation, but Tim Lynch, chief financial officer for Tercica, told BioWorld Today the company has a "very extensive patent portfolio around IGF-1" based on "years and years of work" by Genentech, and the portfolio represents the strongest intellectual property "in the area we're focused on" - which involves correct short stature.

Tercica's latest quarterly SEC filing concedes that the firm lacks patent coverage on the rhIGF-1 protein. The filing reads, "Although we have licensed from Genentech its rights to its methods of use and manufacturing patents, it may be more difficult to establish infringement of such patents as compared to a patent directed to the rhIGF-1 protein [itself]."

U.S. Patent No. 6,331,414 B1 licensed from Genentech, directed to methods for bacterial expression of recombinant human IGF-1, expires in 2018.

Ross Clark, Tercica's chief technology officer and a founder, noted that IGF-1 was discovered in the 1950s.

"It wasn't sequenced, though, until the early 1980s, and there was no patent on the protein," he said. "In 1983, Genentech filed for the DNA sequence. It took quite a while for the patent to issue for the expression." However, now Tercica has "protection for the way we make the drug, and the most efficient way to make it."