In an attempt to protect the position of the first product it tookto market, Genentech Inc. has filed a patent infringementcomplaint against two other producers of recombinant humangrowth hormone.

Protropin, the South San Francisco, Calif., company's (NYSE:GNE)first product, was approved in 1985, but lost its seven years ofmarket exclusivity under the Orphan Drug Act in October 1992.

Genentech still controls 75 percent of the hGH market in theU.S., however, and is developing a second-generation growthhormone that differs by only one amino acid. This product,Nutropin, lacks a methionine group and is simpler and easier toproduce, company spokeswoman Laura Leber said.

Nutropin is in Phase III trials in short stature associated withchronic renal insufficiency and Turner's syndrome. If Nutropinreceives FDA approval, it would be eligible for orphan drugstatus in chronic renal insufficiency.

Genentech has filed a complaint with the U.S. InternationalTrade Commission, alleging that three of its process patentswere infringed by Bio-Technology General Corp. (BTG) of NewYork and Novo-Nordisk A/S of Denmark when the companiesimported hGH for studies conducted prior to filing new drugapplications (NDAs).

"We have absolutely no reason to believe we infringe anyGenentech patents," said Margeret Jo Ringsted, director ofcorporate communications for Novo Nordisk in North America.She could not immediately confirm Genentech's allegation thatNovo Nordisk imported hGH for studies preceding an NDA ongrowth hormone deficiency in children, growth hormonedeficiency in children due to renal failure, infertility treatment,replacement therapy for adults, fractures, osteoporosis andnasal applications.

BTG (NASDAQ:BTGC) filed an NDA several years ago,spokeswoman Leah Berkovits said, when competing with EliLilly and Co. for orphan drug status. Lilly's hGH was approvedin 1987, but it will lose orphan drug status in March 1994. BTGhas kept the FDA up to date with its application addressingshort stature in children, Berkovits said.

"We have been excluded from the U.S. market becauseGenentech and Lilly have had orphan drug exclusivity," shesaid. "It seems that this attempt on the part of Genentechaddresses the fact that we might be approvable in 1994.Genentech controls 75 percent of the human growth hormonemarket in the United States today. I think what they're tryingto do is maintain that control."

BTG sells hGH in South Korea and Israel, has marketingapproval in several European countries, and a marketingapplication pending in Japan.

Berkovits expects increased U.S. competition to lower treatmentcosts, which range from $15,000 to $30,000 per year per childfor Lilly's and Genentech's products.

Genentech has yet to resolve a patent infringement suit it filedagainst Lilly in 1982 regarding hGH, which both companiesproduce in E. coli bacteria.

Genentech is accusing BTG and Novo Nordisk of infringingpatent No. 4, 342,832, issued Dec. 12, 1982, covering microbialpolypeptide expression; and patent No. 4,601,980, issued July22, 1986, covering microbial expression of the gene for hGH.Novo Nordisk also allegedly infringed patent No. 4,601,980,issued Aug. 3, 1982, on a replicable cloning vehicle for quasi-synthetic genes.

-- Nancy Garcia Associate Editor

(c) 1997 American Health Consultants. All rights reserved.