The government is “very concerned” that a challenge by Swiss drug giant Novartis to local patent law could restrict the global supply of cheap anti-AIDS drugs, the health minister said...“We urge Novartis to desist from this and withdraw from this,” Anbumani Ramadoss told reporters...Novartis has gone to the Madras High Court…against a law that blocks the patenting of minor improvements in known molecules...The [company] argues…the Indian patent system stifles innovation...Ramadoss also warned Novartis that New Delhi could be forced to overrule patents and issue licences for firms to produce vital drugs, if deemed in the public interest...