A "game-changing" drug that prevents people from contracting HIV has been given the green light for distribution to NHS patients in England.

Despite the NHS being at breaking point, the High Court ruled the NHS should fund Pre-exposure prophylaxis (PrEP) at a cost of £20m ($25m) a year, as it was the service's responsibility to carry out preventative health. The drug can reduce the risk of infection by more than 90% if taken correctly.

Critics previously said the drug, which costs £400 per person per month, was too expensive and those at risk should be encouraged to practice safe sex instead, arguing the much-needed cash should be used to fund other treatments, such as drugs to help children with cystic fibrosis.

But Deborah Gold, chief executive of National Aids Trust (NAT), said the drug can actually save the NHS money in the long-term.

She said: "We are delighted to have been vindicated by the court a second time. HIV is a critical issue in the UK where over 4,000 people acquire HIV every year.

"PrEP works, it saves money, and most importantly it has the power to prevent HIV acquisition for thousands of people, at the same time as beginning to end the HIV epidemic. This judgement brings that possibility one step closer."

PrEP pills used for preventing HIV iStock

The drug is now being trialled for three years by 10,000 patients, deemed to be high risk due to their partners having the infection.

NHS England, which fought not to offer the drug, said they would not appeal the High Court decision.

Dr Ian Williams, chairman of NHS England's group on HIV, said: "This announcement demonstrates NHS England's commitment to fund PrEP and provides the chance to best prepare England for optimal roll-out following this large-scale clinical trial.

"For now, the trial will provide access to PrEP for thousands of people most at risk of acquiring HIV."