Baltimore — In the biggest effort yet to find a cure for HIV, the National Institutes of Health on Wednesday named six large scientific teams to tackle different parts of the challenge.

The government will commit $30 million a year for five years to the effort. One team, led by Philadelphia’s Wistar Institute and the University of Pennsylvania, will get $4.6 million a year.

For years, with the world focused on getting treatment to millions of infected people and preventing further spread of the disease, the notion of a “cure seemed naive and overambitious,” said Luis J. Montaner, a Wistar scientist who will share leadership of the Philadelphia team. “People didn’t use the word.”

That has gradually changed, with major funding now being dedicated to finding a vaccine and an outright cure.

“A simple, safe, and scalable cure for HIV would accelerate progress toward ending the HIV/AIDS pandemic,” NIH Director Anthony S. Fauci said in a statement announcing the teams, five days before the start of the international AIDS conference in South Africa.

In a departure from the way that research is typically funded, the NIH requested proposals from large teams that would work collaboratively.

Also involved in the partnership are the VA San Diego Healthcare System, the University of Nebraska and the University of Utah.

The NIH grant, officially part of the Martin Delaney Collaboratory: Toward an HIV-1 Cure, will provide $23 million over five years to the Philadelphia group. Montaner estimated that at least $18 million of that would remain in the city.