US drug giant Pfizer said Friday it will appeal against an Indian ruling overturning a patent for a cancer drug, saying the decision sparks questions about intellectual property protection in India. Indian generics drugs heavyweight Cipla teamed up with other generic local pharmaceutical companies to oppose the granting of the domestic patent for Sutent, which is used to fight liver and kidney cancer. The decision went to the heart of India\'s patent act, which says a patent cannot be granted for a drug unless changes make it significantly more effective and innovative. \"The patentee (Pfizer) has miserably failed to demonstrate any improved activity\" warranting a patent, the office said in its decision. \"I conclude that the invention that is claimed in the patent does not involve any inventive step... and hence (is) not patentable,\" Nilanjana Mukherjee, senior patent officer, said. A spokesman for Cipla, which revolutionised AIDS treatment by supplying cut-price drugs to the world\'s poor and which has been campaigning to be able offer other low-cost generic drugs, had no immediate comment. But Pfizer managing director Jazz Tobaccowalla said the company believes the ruling \"undermines intellectual property rights in India\". \"We will vigorously defend our basic Sutent patent,\" the Pfizer executive said in a statement, adding the company would appeal against the ruling to India\'s Intellectual Property Appellate Board. The patent decision marked another win by Cipla against a high-profile global pharmaceutical company. In September, a court threw out a patent infringement case launched against it by Swiss drugmaker F. Hoffmann-La Roche over the Mumbai firm\'s version of a lung-cancer drug, ruling it had a different molecular makeup. The cases have been watched worldwide as they involve interpretation of stricter drug patent protection rules introduced by India in 2005 to comply with World Trade Organization regulations. India is the world\'s leading exporter and manufacturer of non-branded medicines. Medical charities have expressed concern that compliance with WTO rules could reduce the country\'s role as a supplier of cheap medicines. But Western firms are sceptical about protection in India where low-costing generics comprise more than 90 percent of sales and the government is under pressure to make drugs affordable to the mainly poor population.