Brazil, which has a much-copied universal free Aids programme, has for years threatened to break patents in its drive to cut the cost of foreign drugs used in its 15-drug anti HIV-Aids cocktail.
It will make the move in 2005 when it begins domestic production of three to five drugs without permission from the companies that hold the patents, Pedro Chequer, head of the government's Aids programme said.
Chequer did not specify which patents would be broken.
Under Brazilian law, and based on World Trade Organisation rules, a nation can break drug patents by applying a "compulsory licence" on a product if it is a case of national emergency or national interest.
Brazil says it can no longer afford to run its free anti-Aids programme using imported drugs.
"We determined that we have to move to a situation of self-sufficiency through compulsory licensing," Chequer said. "If we don't move towards self-sufficiency, the programme will collapse."
He added: "We see mergers of multinationals, regional monopolies, it's all a big agreement to keep developing nations hostage to the multinational industry."
Brazil has a universal and free
Aids drugs programme
In the mid 1990s Aids experts expected millions of Brazil's young, sexually-active population to fall prey to the disease.
Brazil began free access to the cocktail of drugs in 1997. It has kept the number of people living with HIV at about 600,000. Nearly 150,000 Brazilians currently receive the HIV-Aids drug cocktail, almost half the total of 350,000 who receive such treatment throughout the developing world.
The cost of providing foreign imports of drugs in the cocktail has skyrocketed from 50% of the programme's budget in 1998 to an estimated 85% in 2005.
Brazil currently makes seven of the drugs in its cocktail and hopes to begin manufacture of more in the first half of 2005.
But the South American country still lacks pharmaceutical industry technology and the capacity to supply all 15 of the drugs, Chequer said.
"Breaking patents means vertical national production from start to finish, so that we are not dependent on any other country for essential materials," he added.
Newly released data indicates the spread of Aids stabilised in 2004 in the nation of 180 million people, but was rising among poor, black and mixed-race Brazilians. Figures also show the disease has reached record levels among women.