A compulsory license allows Brazil, under World Trade Organization (WTO) rules, to buy or manufacture generic versions of the drug. Thailand recently earned itself a place on the Office of the US Trade Representative's priority watch list after breaking patents on Sustiva and Abbott's Kaletra, although the move was praised by AIDS activists.
Merck had offered to cut the price of the drug by 30% to $1.10 a pill, but according to the AIDS Healthcare Foundation, Brazil had asked for a reduction to 65 cents per pill, which Merck refused. Brazil offers free universal access to HIV drugs, and is looking to lower the costs of the scheme.
Flexibilities under the WTO agreement allow governments to issue compulsory licenses (including royalty payment to the patent owner) if the country deems it necessary and appropriate to protect the health of its citizens.