The Aids Foundation says it's a fiscal no-brainier to fully fund a drug that prevents the spread of HIV.
Medsafe has approved use of PrEP (prep), an anti-viral cocktail the US Centers for Disease control says reduces the risk of contracting HIV via sexual contact by 90 percent.
But the $1000/month cost of the drug is not yet funded by Pharmac.
Aids Foundation executive director Jason Myers says prevention would save millions of dollars every year.
"The cost of making Prep available to those who need it is between $1 and $2 million a year - really small fry when you consider the cost of treating HIV-positive people has doubled in five years to $32 million."
Around 3200 Kiwis are estimated to be living with HIV. Last year's increase of 244 confirmed cases was the biggest in history.
Mr Myers hopes the new Government, which is sworn in on Thursday, will take a different stance on its use.
"Investing and making pre-exposure prophylaxis available can bring significant gains - not only financial, but human, over the long-term. We're hoping we see some shift in this sooner than later."
Pharmac and incoming Health Minister David Clark have been contacted for comment.