By Clare Gurton (

Merck has slashed the price of anti-HIV drug Efavirenz in Thailand, two months after Thailand announced a compulsory licence to manufacture a generic version.

This week, it threatened further compulsory licences against another two products, including Plavix, Sanofi-Aventis’s best-selling blood-thinning drug, a move that is legal under world trade laws yet faces major criticism outside the country.

Mongkol na Songkhala, the senior health ministry beaurocrat leading these patent challenges, says this is the only way he can ensure that he can provide health services to Thailand’s 63 million people, and totally rejects industry arguments that high prices are necessary for R&D investment.

Thailand has been leading the fight against the HIV/AIDS epidemic in Asia, but high drug prices for key HIV/AIDS drug have been a big obstacle, so at one level, Thailand’s move is understandable since it faces a real challenge in treating a large number of HIV-positive patients with drugs that are costly even for rich countries.

The debate over whether innovation is best protected and stimulated by the existing patent regime is an important one. But forcing the issue in Thailand when there is scant evidence of the effectiveness of alternative models could be counter-productive.