Cipla's joint managing director Mr Amar Lulla said: "It only vindicates our stand that such patents are blocking out less expensive generic competition in the AIDS segment." Activist group Consumer Project on Technology has all along claimed that both BMS drugs were researched and developed with public money - stavudine by Yale University and didanosine by the US National Institute of Health (NIH) and subsequently licensed to BMS.

GSK had earlier threatened legal action against Cipla when the Indian company had imported its generic Duovir (Cipla's generic equivalent of Glaxo's Combivir) into Ghana, alleging patent infringement. The legal validity of Glaxo's patents are debatable as three of the four patents were applied for even before Ghana allowed patenting of pharmaceutical products.AIDS activists are now taking their battle further, even as South African president Thabo Mbeki on Wednesday rejected calls to declare a state of emergency to allow generic imports to deal with the AIDS crisis.

Activists now want pharma firms to hand over their patents in developing countries on all essential medicines involved in the treatment of HIV/AIDS to the WHO. Besides a royalty, activists have called on all governments to charge a 1 per cent R&D levy on all generic medicines.