These patent-protected medicines are used to treat diseases such as cancer, diabetics and hypertension. Under the current laws, no drug company can manufacture or market low-cost versions of these medicines until the expiry of their patents.

Data submitted by the Ministry of Commerce and Industry to the Lok Sabha in response to a query from R Senthil, convenor, Indian Medical Parliamentarians' Forum, revealed that India has given 460 product patents between January 1, 2005 and August 31, 2007. Only 68 of these patents belonged to Indian drug companies. The data also showed that of the 460 patents, 436 were granted during the first eight months of 2007.

Responding to the ministry disclosure, Anand Grover of civil society group Affordable Medicines and Treatment Campaign said that an inquiry should be conducted to ascertain if the substantive law and procedures were complied with while scrutinising these patent applications.

"The Indian patent law is more stringent than that of the US. Only new innovations (and not minor modifications of known products) can be patented here. If you look at the actual number of new innovations that got approved in the US, it would be around 250. How can there be more innovations here," he asked.

"The ministry data is more than one year old. Indian patent offices have granted more than 1,000 product patents for medicines until now. We need to properly look into these patent grants," he added.