In the latest row between global drugmakers and governments over affordable medicines, China’s State Intellectual Property Office revoked the patent on Viread, a drug sold by Gilead Sciences for treating HIV/AIDS and hepatitis B, after a challenge by Aurisco, the largest manufacturer of active pharmaceutical ingredients in the Asian country. It is said that the rational for the move was that the Viread patent lacked novelty and was not entitled to protection. And in this instance, the decision means that, unlike when a government issues a compulsory license to a specific patent challenger, the Chinese market for Viread will now be opened to numerous competitors.