Challenges to domestic drug patents growDomestic drug companies, who have been challenging drug patents in the US and Europe, are now taking the first steps to challenge patents granted in India to companies based there.

At least a dozen companies have applied for marketing approvals of medicines that have patent protection in India. These patents are owned by global pharma majors like Pfizer, Merck, Roche and Bayer. India allowed product patent protection for drugs from January 1, 2005.

Challenges to domestic drug patents growFor instance, Sun Pharma and Hetero drugs have approached the Drugs Controller General of India (DCGI) for marketing approval for generic versions of Pfizer’s anti-HIV medicine, Selzentry, which has patent protection in India. DCGI is processing both applications.

Marketing approvals, once granted, could be used to launch the product, which means a patent challenge. The owner of the patent could then sue the company for patent violation.

According to Amar Lulla, joint managing director of Cipla, the country’s largest drug seller, Indian companies apply for marketing approval for patented products for several reasons. “It could be because we feel the patents are invalid or it could be for exports to countries where there is no patent infringement,” he said.

The companies also seek marketing approval from the drug regulator to export these medicines to least developed countries where there is no product patent obligation. Ranbaxy, Cipla and APC Pharma are among the companies who have obtained such no-objection-certificates from the drug regulator to export generic versions of Baraclude (entecavir), a drug given to patients with chronic hepatitis-B virus infections. Bristol Myers Squibb owns a product patent for the drug in India.

Domestic companies are able to seek marketing approval for patented products as India’s drug laws do not link the patent status of a medicine to its marketing approval. “Whenever a company applies for a new drug, we ask them about the patent status of the product. If the company is willing to take the risk of launching a product irrespective of the patent status of the medicine, it’s their decision. Our role is to see if the medicine is safe and efficacious,” a senior regulatory official said.

Domestic drug makers say marketing approval does not infringe anyone’s patent until companies decide to launch the product. “Approval from the drugs controller does not mean the companies are going to market the product. For small firms, it could be preparedness to hit the market at the first opportunity, if a big domestic player opposes and reverses the patent,” said D G Shah, secretary general of Indian Pharmaceutical Alliance (IPA), the select club of big Indian drug companies.

For instance, Cipla had launched the generic version of the bird flu drug, oseltamivir, even when a patent application for Tamiflu, the branded drug from the innovator company, Gilead, was pending. The patent office later denied the Gilead application.

This provision that allows companies to seek marketing approval for a medicine with a valid patent is a matter of concern to multinational corporations. German drug maker Bayer had taken Cipla to court to prevent the Indian company from getting marketing approval for its patented medicine. Bayer wanted the court to restrain the drug regulator from giving marketing approval for generic versions of Nexavar (sorafinib tosylate), its patent-protected cancer medicine, to generic competitors such as Cipla. The litigation is ongoing and the drug regulator’s decision in this case will depend upon the outcome of the litigation.