Sandoz?s recombinant human growth hormone gets FDA okay, despite critics? concerns of inadequate testing
By Aaron J. Bouchie | June 1, 2006
The US Food and Drug Administration approved on Tuesday (May 30) a controversial drug some experts say is the first biogeneric, despite critics' concerns that the company did not perform adequate safety testing. However, the agency cautions that the approval should not open any doors for biogenerics.
The product, a recombinant human growth hormone (rhGH) marketed as Omnitrope by Sandoz, has been called a biogeneric because its active ingredient in Omnitrope is somatropin, the same as in Pfizer's Genotropin, another recombinant human growth hormone that has been on the market since 1998. In addition, Sandoz submitted its application through a process that is normally used for generic drugs.
However, in its approval document, the FDA calls Sandoz's Omnitrope a "follow-on protein product," not a biogeneric, and says its approval "does not create a new pathway for follow-on versions of all protein products." Unlike with other generics, patients can't take a prescription for Pfizer's Genotropin, for example, and go to the pharmacy and receive Omnitrope instead; doctors must write a prescription specifically for Omnitrope.
The FDA also does not address scientific issues with many other biologics. As a result, the decision avoids setting a precedent for many lucrative biologics currently in development by generics companies, such as erythropoietin and interferon.
Still, the decision sends a clear message, Charlie Mayr, a spokesperson for the Generic Pharmaceutical Association, told The Scientist. "One of the most significant things about the Omnitrope approval is it shoots down lots of misperceptions about biogenerics companies," he noted. "They are sophisticated pharma companies with the scientific, medical, clinical and manufacturing expertise to get their products to market."
Biogeneric firms such as Barr Pharmaceuticals have supported the approval, while companies such as Pfizer and Genentech that sell protein therapeutics argued that the normal, generic drug approval process is not adequate for this new drug. Indeed, Pfizer, as well as the developers of the other five rhGHs that are currently on the market, went through a full approval process with large, expensive clinical trials. Sandoz, on the other hand, performed four small clinical trials, relying on Omnitrope's similarity to Genotropin to get approval.
Petitions submitted to the FDA by Genentech, Pfizer, and industry lobbyists argued that full-blown clinical trials are necessary to guarantee the safety and efficacy of protein therapies because they are more complicated than small molecules. "We're not worried about the competition. We're worried about the safety of patients," Walter Moore, vice president of government affairs for Genentech, which markets its own rhGH called Nutropin, told The Scientist.
Sandoz did extensive testing including animal studies, in addition to its clinical trials, which enabled the FDA to state in its 53-page response to petitioners "that, despite their differences, Omnitrope and Genotropin are highly similar in their clinical effects." And because of this clear similarity, the FDA also relied on its previous "finding of safety and effectiveness for Genotropin to support approval of Omnitrope."
Although the FDA ultimately approved Omnitrope with fewer clinical trials, the agency repeatedly makes clear that it did so because of the product's simplicity and the long history of hGH therapy. (The product was first used as a treatment in 1958, and the FDA has approved seven rhGH products since 1985).
Omnitrope was approved this April in Europe and has been on the market in Australia since November 2005. Sandoz first submitted its new drug application to the FDA in July, 2003. Two months ago, the company won a federal lawsuit forcing the agency to make a decision on the product.
Representatives from the FDA and Sandoz did not return requests for comment.
Aaron J. Bouchie
Links within this article
Omnitrope label history
D. Wilkie, "Can biotech be generic?" The Scientist, December 20, 2004.
A.McCook, "Manufacturing on a grand scale," The Scientist, February 14, 2005.
"Sandoz gets precedent-setting US approval for Omnitrope as first follow-on version of a previously approved recombinant biotechnology drug," Sandoz, May 30, 2006.
Generic Pharmaceutical Association