Truvada was previously approved as a treatment for people infected with HIV to be used in combination with other antiretroviral drugs.

Washington - US regulators on Monday approved the first drug to reduce the risk of becoming infected with HIV among individuals at high risk of acquiring the virus that causes Aids.

The drug Truvada was approved by the US Food and Drug Administration to be used in combination with safe sex practices to reduce sexually-transmitted HIV infection among those with a high likelihood for infection, such as those with an HIV-infected partner.

The move follows the recommendation of a review board that suggested approval of the drug, which had already been given the green-light for use in treatment of HIV along with other antiretroviral drugs.

“Today's approval marks an important milestone in our fight against HIV,” said Food and Drug Administration Commissioner Margaret Hamburg.

She pointed to the need to prevent the 50,000 new infections that appear each year despite ongoing efforts to halt the spread of the disease.

“New treatments as well as prevention methods are needed to fight the HIV epidemic in this country,” she said.

The FDA relied on two studies that showed the reduced risk of HIV infection among both heterosexuals and homosexuals.

Critics have expressed concern that the drug could lull its users into a false sense of security, while others worry about the drug's high cost or the possible emergence of a drug-resistant HIV strain. The daily pill must be used alongside condoms, the regulators said.

The announcement comes one week before an international Aids conference in Washington at which 25,000 participants are to discuss the status of the fight against Aids as well as new scientific studies. - Sapa-dpa