The body argued that providing the drug — pre- exposure prophylaxis (PrEP) — was not its responsibility and it was for local councils to fund “preventative” health treatment.
Mr Justice Green, sitting in London, disagreed and ruled that NHS England had erred in law and it did have the power to commission PrEP, a highly effective anti-retroviral drug used to stop HIV from becoming established in the event of transmission.
The ruling was a victory for leading charity National Aids Trust with backing from the Local Government Association.
When taken consistently, PrEP has been shown to reduce the risk of HIV infection in people who are at high risk by more than 90%.
Allowing National Aids Trust’s application for judicial review, the judge said the core of the legal challenge was about “the allocation of budgetary responsibility in the health field”.
He said: “No one doubts that preventative medicine makes powerful sense. But one governmental body says it has no power to provide the service and local authorities say they have no money.
“The claimant is caught between the two and the potential victims of this disagreement are those who will contract HIV/Aids but who would not were the preventative policy to be fully implemented.
“In my judgment the answer to this conundrum is that NHS England has erred in deciding that it has no power to commission the preventative drugs in issue.”
Alternatively, said Justice Green, NHS England has “mischaracterised the PrEP treatment as preventative when in law it is capable of amounting to treatment for a person with infection”.
In any event NHS England had the power to commission preventative treatments because that facilitated, or was incidental to, “the discharge of its broader statutory functions”.
The judge gave NHS England permission to appeal against his ruling to the Court of Appeal.
Campaigners say while the majority of gay men use condoms to prevent HIV infection, there is also an “ethical duty” to provide PrEP to those who do not.