A spokesman has affirmed that India has partly revoked patents granted to Roche Holding AG for its breast cancer drug, Herceptin. According to reports of Swiss newspaper Schweiz am Sonntag, divisional patents for Herceptin had been lifted by Kolkata Patent Office on July 17.

It was based on the grounds of improper submission. "I can confirm that the Assistant Controller of Patents at the Kolkata Patent Office has revoked divisional patents of Herceptin and that we are now considering the further course of action", a spokesman for Roche said.

The decision has frustrated the attempts being made by Western drug-makers to enter India's drug market. India has emerged as a fast-growing drug market, which has tempted many renowned drug-makers around the world to establish a foothold in India's drug market.

It was the latest decision in a series of rulings on intellectual property and pricing in India. A patent granted to GlaxoSmithKline for breast cancer drug Tykerb was revoked by India on Friday.

Roche has already entered India's drug market. It introduced cut-price versions of Herceptin and another cancer drug MabThera in August 2012. The drugs were introduced under an alliance with Indian generics firm Emcure Pharmaceutics. Roche is following an approach that allows affordable access to drugs in India.