Those at high risk of coming into contact with HIV in Wales will be able to access Prep as part of a three year trial.
The Health Secretary Vaughan Gething has announced an all-Wales study to provide the drug Prep - or Truvada® to all those who would benefit from the preventative treatment.
The announcement follows the decision on Truvada® by the All Wales Medicines Strategy Group. The study will run for at least three years and will begin this summer.
Vaughan Gething said: "There is no doubt that Truvada® reduces rates of HIV infection when taken correctly and supported by wider, preventative sexual health services can help to reduce overall HIV transmission and infection rates. This is the advice of the World Health Organisation.
"The study that I have announced will mean that all those for whom the drug is clinically appropriate can access it.
"The study will help us to learn how best to provide the preventative treatment to reduce risks of HIV transmission in Wales and answer some of the questions raised by the All Wales Medicines Strategy Group around incidence rates.
"The All Wales Medicines Strategy Group is a highly regarded, independent expert group. I acknowledge their advice that there are uncertainties regarding cost-effectiveness and that they have not recommended the drug for routine use within NHS Wales at this time.
"I am asking Public Health Wales and the HIV Expert Group to work together to deliver the study."
Andrew White, Stonewall Cymru Director, said: "PrEP has been shown to be highly effective at lowering rates of HIV transmission. This trial will allow Wales to protect those most at risk and given that it costs much more to treat than to prevent HIV, in the long-term this will also save NHS Wales money.
"Although this is a temporary measure, we will press for Welsh Government to make PrEP available long-term for those who need it following the three-year trial. Of course, PrEP is not the sole answer to tackling HIV transmission.
"This preventative measure should be accompanied by high-quality sex and relationships education - the majority of LGBT young people still say they don't receive the information or guidance they need to stay safe.
"We will continue to work with the Welsh Government and others to update existing guidance on SRE so that LGBT young people are equipped to make safe, healthy decisions about their wellbeing."