Generic Renvela Maker Files for FDA Approval

Generic drug makers have been going after phosphate binders for short while now; however, it could reach a fever pitch after Genzyme sued Impax Laboratories on July 1 for trying to create a generic form of Renvela.

This fight has been going on since at least last year when Impax attempted to develop a generic version of Genzyme’s previous phosphate binder Renagel. In response, Genzyme filed a lawsuit in Maryland alleging patent infringement.

History seems to be repeating itself this year after Impax filed for regulatory approval of a generic form of Renvela. And Genzyme, once again, filed for patent infringement.

In a news release, Impax said it filed an Abbreviated New Drug Application containing a paragraph IV certification for a generic version of Renvela with the U.S. Food & Drug Administration.

“Paragraph IV” certification was created by the Drug Price Competition and Patent Term Restoration Act of 1984. This act, also known as the Hatch-Waxman Act for Rep. Henry Waxman, D-Calif., and Sen. Orrin Hatch, R-Utah, established the modern system of generic drugs.

According to the U.S. Federal Trade Commission, by using a Paragraph IV certification, Impax can claim that the Genzyme’s patents are invalid or will not be infringed by the manufacture, use, or sale of the generic products.

The Hatch-Waxman Act, however, allows the branded company to block the FDA approval process by filing suit, which Genzyme  did. As a result of the lawsuits, the FDA stays final approval of the generic drugs until one of three things happens: 1) patent expiration; 2) a final determination by a court of non-infringement or patent invalidity; or 3) the expiration of a 30-month period from the time the ANDA filer notifies the patent holder of a Paragraph IV certification.

Impax has been down this road before. In May 2009, the FDA granted approval of Impax’s Abbreviated New Drug Application for generic versions of Precose Tablets (acarbose), 25 mg, 50 mg and 100 mg strengths. Precose is a Bayer HealthCare Pharmaceuticals product.

It should be interesting to see how their latest foray plays out.