This week's Sunday Spotlight gives the stage to U2 frontman Bono, who has been a leader in the global fight against AIDS for more than a decade. Helping "This Week" mark World AIDS Day, Bono sat down with ABC's George Stephanopoulos to talk about the dramatic turnaround in the battle against a virus that has killed more than 25 million worldwide since 1981.

Antiretroviral drugs, once unaffordable to the majority of people affected by HIV/AIDS, are now significantly more accessible.

"They used to cost a fortune, you know, ten grand a year. It's down to 40 cents a day for one pill," Bono said. "I remember being in Malawi, in Lilongwe, where there was four to a bed, queuing up to be diagnosed. But the diagnosis was a death sentence because there was no treatment. They had the medication. But they couldn't give it to them. They couldn't afford it."

Bono, who is co-founder of ONE and the (RED) Campaign, said a person's ability to access antiretroviral drugs was an "accident of where you live." Unequal accessibility to HIV/AIDS treatment, often exacerbated by political or corporate interests, made Bono "ready to put his life on the line" for the fight against HIV/AIDS.

"It actually really was an assault on my whole idea of equality. And so the charity bit went out the window for me. It became a justice issue," he said. "We can't have these technologies, simple, cheap and be denying them to others."

But changes are happening now, he said. And though Bono recognizes there are still obstacles, he says there is an end in sight.

"There does seem to be the political will. The American people have said that this fight against HIV/AIDS, this tiny, little virus that's wreaked so much havoc in so many people's lives…they got it in their sights. They want to see it done. And that is so inspiring to me," he said.

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This year, Congress reauthorized PEPFAR, a program started by President George W. Bush, which has dedicated billions of dollars to the fight against AIDS.

"We argued with President Bush about setting up PEPFAR," Bono said. "We thought, 'Why not just stick with The Global Fund', which is the multilateral mechanism."

But President Bush, Bono said, wanted a uniquely American organization so the government could "keep an eye on it" and do it "properly."

Political interests are coming together this Tuesday at The Global Fund's Conference, which the U.S. government is hosting.

"Even though originally Republicans historically supported PEPFAR, and Democrats The Global Fund, that has changed," Bono said. "This is incredible. This is what happens when people put their ego and political point-scoring away for a bigger purpose and they stop playing politics with the poor."

These organizations are seeing great results - but Bono's main concern is complacency.

"There's a chance of having the first AIDS-free generation by 2015, 2016. We can see it. We could lose that if we lose the political will," he said. "I would just say to people, 'Hold on tight to this one.'"

Visit World AIDS Day's website to learn more about supporting the cause.

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