Bangalore: In a blow to pharma giant Pfizer, the Delhi Patent Office has revoked its patent for sunitinib (brand name Sutent) granted in 2007. Sutent is used to treat a type of kidney cancer and the drug had global sales of $1.19 billion in 2011. The Indian Patent Office revoked the patent on the ground of lacking an innovative step.

The revocation decision comes after a post-grant opposition filed by Indian pharma major Cipla and NATCO Pharma. Post-grant opposition is the option to challenge the grant of a patent. Mr Aijaz Tobaccowalla, MD, Pfizer India, in a statement to the media said "we believe the decision undermines intellectual property rights in India and we will defend out basic Sutent patent".

The decision comes at a time when pharma majors around the world are closely watching the Indian intellectual property scene, following the compulsory licensing decision on Bayer's Nexavar and the Novartis case against the Indian Patent Office for refusal to grant it a patent for Glivec.

Pfizer's Sutent costs approximately $3800 (Rs 1.96 lakh) for a 45-day treatment or $84 (Rs 4,357) for a 25 mg capsule. The patent granted Pfizer a monopoly over this drug in the market. Given the cost, Pfizer started the Sutent Patient Assistance Program (SPAP) four years ago to make Sutent available to all patients irrespective of their income. The program offers eligible patients either a partial or fully subsidized treatment based on medical and socio-economic criteria.

This is the second major patent revocation in the country. In 2010, the Chennai Patent Office revoked Swiss firm Roche's patent on HIV drug Valcyte following post-grant opposition by patent groups. Valcyte was then priced at Rs 1,023 per tablet while the generic versions were priced at Rs 245 per tablet.