Kampala, Sep 20 (Xinhua) A drug designed to reduce the risk of HIV transmission and meant to be taken before unprotected sex is to be tested in Uganda, a media report said Saturday.The pill has proved successful in monkeys and initial tests on human beings have shown encouraging results, the state-owned Saturday Vision newspaper quoted Patrick Ndase, who is coordinating the drug trial, as saying.

A team of Ugandan and American scientists are preparing for a phase three trial, which is considered the final test before the drug goes into use.

The pill would help discordant couples, where one person is HIV positive and the other is HIV negative, to produce children without spreading the infection. It would also help a woman protect herself in case her sexual partner does not want to use a condom.

Ndase said they are enrolling volunteers from different parts of the country for the trials.

“Overall, we want to enrol 3,900 discordant couples on a volunteer basis and follow them up for a planned period of four years,” Ndase said.

Taking a drug to pre-empt infection is called pre-exposure prophylaxis. It has been used against malaria and tuberculosis.

The trial, funded by the Bill and Melinda Gates Foundation, is a partnership involving universities, government departments and NGOs in Uganda and the US.

According to documents from the AIDS Vaccine Advocacy Coalition (AVAC), drugs under study are tenofovir disoproxil fumerate (TDF), commercially known as Viread, and TDF combined with emtricitabine (FTC), commercially known as Truvada.

The two drugs are broad antiviral drugs that can be used for all HIV types, according to Ndase.

“As ARVs (antiretroviral drugs), they are effective both at early and late stage of the infection and as a prevention tool, they can block initial infection. They have no food or drug restrictions and will soon be very affordable because their patent period is ending soon,” he said.

AVAC, a non profit organization carrying out global advocacy to expand HIV prevention, said that the trials are currently planned or going on in many countries of Africa, Asia, Latin America and the US.

“At this point, no one knows whether it will work,” a statement said. “But if it does, it will be used in combination with current HIV prevention methods, including safer sex practices, condoms, treatment of sexually transmitted diseases, risk reduction counselling, safe needles, and male circumcision.”