FDA admits Sun’s appeal

US drugs regulator food and drug administration (FDA) has accepted a generic challenge by India’s Sun Pharmaceuticals Industries Ltd against Glivec, a controversial mega-earner cancer drug of Novartis AG, potentially weakening the Swiss drug maker’s petition against an Indian ruling denying the drug a patent. The challenge in the US, if it invalidates Novartis’ patent, will not only significantly stre-ngthen the plea of local drug makers here, but also open up a huge generics market for them in the US for this drug, which, last year, grossed some $2.5 billion (Rs11,605 crore then), equivalent to more than one-10th of Novartis’ revenues.
Novartis’ patent on Glivec was challenged by Sun Pharma through what is called a Para IV filing with FDA. The filing initiates a process with which a generics firm can seek marketing approval for an already patented product either by invalidating the patent, by proving there is fundamentally nothing novel in the product or by proposing to introduce a variant without infringing the patent. The appeal was listed early this month by FDA after a six-month surveillance by the regulator. Under the rules, Novartis is expected to respond to this challenge within 45 days of the date of listing.

Earlier, Novartis has challenged the Indian patent office’s decision to turn down its patent application through an appeal filed early in 2006 in the Madras high court. The case has since shifted to the Intellectual Property Appellate Board, or IPAB, which hears such disputes in the country. In 2006, the Chennai patent office refused Novartis’ patent claim for Glivec—which is a beta crystal or polymorphic form of the known cancer drug Imatinib Mesylate—on the ground that it is not an innovation and the Indian patent law does not identify this as patentable. One of the newly amended provisions in the Indian patent law, Section 3D, specifies that no derivatives or modified forms of known drug substances are patentable unless it enhances the therapeutic efficacy substantially.