FDA Approves Sandoz's Omnitrope as Follow-on Protein Product

Sandoz (Holzkirchen, Germany, www.sandoz.com), the generics arm of Novartis(Basel, Switzerland, www.novartis.com),received approval from the US Food and Drug Administration (Rockville,MD, www.fda.gov) for"Omnitrope" (somatropin [rDNA origin]), a follow-on version of apreviously approved recombinant human growth hormone (rhGH) product. 

FDA's decision follows the approval of Omnitrope by European regulatoryauthorities in April 2006. Sandoz had filed a lawsuit against the FDAin September 2005 seeking a ruling on its new drug application, whichit filed in July 2003.

In approving Omnitrope, FDA emphasized that the drug is not a genericbiologic because it is not rated as therapeutically equivalent to any ofthe other approved human growth hormone products. Instead, FDAcharacterizes the drug as a "follow-on protein product"(www.fda.gov/cder/drug/infopage/somatropin/qa.htm) and stresses thatits approval does not create a new pathway for follow-on versions ofall protein products.

"The approval of Omnitrope in a 505 (b)(2) application does notestablish a pathway for approval of follow-on products for biologicalproducts licensed under Section 351 of the Public Health Service Act,nor does it mean that more complex and/or less well understood proteinsapproved as drugs under the Food, Drug, and Cosmetic Act could beapproved as follow-on products," said FDA. "The majority of proteinproducts are licensed as biological products under the Public HealthService Act, not approved as drugs under the Food, Drug, and CosmeticAct. There is no abbreviated approval pathway analogous to 505 (b)(2)of 505 (j) of the Act for protein products licensed under Section 351of the Public Health Service Act. Such a pathway for the approval orlicensure of follow-on protein products under the Public Health ServiceAct would require new legislation."  

FDA also points out that its approval of Omnitrope does not involve theregulatory and legal questions raised with follow-on products licensedunder the Public Health Service Act. These issues involve: proteinproducts with unknown or multiple active ingredients; (rhGH productshave one known active ingredient, somatropin); protein products thatare difficult to characterize (currently available technologies allowrhGH to be extensively characterized); protein products that areglycosylated (rhGH is not glycosylated); and protein products that havean unknown mechanism of action (rhGH's mechanism of action is wellunderstood).

In its statement, the agency also pointed out that Omnitrope is notFDA's first approval of a follow-on protein product. Other follow-onprotein products approved under section 505 of the Food, Drug, andCosmetic Act include: "GlucaGen" (glucagon recombinant for injection),"Hylenex" (hyaluronidase recombinant human), "Hydase" and "Amphadase"(hyaluronidase), and "Fortical" (calcitonin salmon recombinant) nasalspray.