Public health advocacy groups say they are dismayed a drug that can reduce the spread of HIV will not gain a federal subsidy as a preventative measure.

Earlier this year, the Therapeutic Goods Administration approved the use of the anti-retroviral drug Truvada as a pre-exposure prophylactic (PrEP) to reduce the spread of sexually transmitted HIV.

The pill, taken once daily, had become popular with thousands of gay men in Australia who wanted to reduce their risk of contracting HIV.

The drug is up to 95 per cent effective in preventing HIV infection, according to the HIV Foundation.

It is already listed on the Pharmaceutical Benefits Scheme (PBS) as a treatment for people who have contracted HIV.

But the independent Pharmaceutical Benefits Advisory Committee (PBAC) yesterday recommended Truvada not be added to the PBS as a preventative drug, citing concerns it would not be cost-effective.

President of the Australian Federation of AIDS Organisations Bridget Haire said the ruling was disappointing.

"What it means is there's no simple, equitable way of people who are at high risk of getting HIV of acquiring [Truvada] around the country," she said.

"What we are seeing is a picture where if you're a gay man at high risk of HIV, your access to health depends on where you live."

Ms Haire said people could still buy Truvada by contacting their local AIDS councils, seeing a doctor to import the drug for personal use, or by joining PrEP trials running in New South Wales, Victoria and Queensland.

"But obviously those things are complex," she said.

"It's just not as simple as going to your doctor or going to your chemist in the way that you do normally for safe and effective drugs."

Preventative treatment 'would cost up to $200K a year'

The PBAC noted the cost of treating someone at high risk of HIV infection with Truvada would cost between $105,000 and $200,000 a year.

"In order to make Truvada available for PrEP to the whole at-risk population a substantial reduction in price would be needed to achieve cost effectiveness," the PBAC said.

Ms Haire said she hoped drug manufacturer Gilead would consider reducing the price of the drug so the Federal Government could subsidise it.

"We believe, and there's mathematical modelling to support this, that really good access to Truvada across Australia for all the people who need it will at least halve new HIV infections over the next year," she said.

In Queensland, a $6 million PrEP trial is underway for 2,000 men.

When he announced the expansion of the trial earlier this year, State Health Minister Cameron Dick said the best way for PrEP to become widely available would be through a PBS listing.

"The Palaszczuk Government is stepping up to the mark, but it is crucial that the Federal Government plays its part in HIV prevention by ensuring a PBS listing for this valuable medication," he said.