After decades of steep increases in the number of people worldwide living with AIDS, at the end of 2011, something positive happened: The devastating plague started to level off in one of the greatest public health victories of the modern age. Now, however, pharmaceutical industry pressure on the biggest source of the drugs that stemmed the epidemic — India –could put a hitch in that progress.There are lots of reasons AIDS is more under control these days, from improved sexual education to needle exchange programs. Most important, though, is the widespread availability of anti-retroviral drugs, which allow HIV and AIDS patients to live with lower viral loads, making it less likely that they’ll pass the disease on. That never would have worked if off-brand manufacturers hadn’t been able to produce the pills at a much lower cost than the drug companies who’d brought them to market initially. And a huge percentage of those manufacturers are in India, which produces 86 percent of the AIDS drugs being taken around the world.The American pharmaceutical industry has never been happy about competition from the Indian generics, which drive down prices. And lately, they’ve stepped up their complaints — the Chamber of Commerce has labeled India an “international outlier on intellectual property,” as part of a broader campaign to push back against the subcontinent’s economic protectionism. There’s been intense pressure on the U.S. trade representative and on Wednesday the White House, which earlier this year put India on a special trade blacklist over its patent laws, sent Vice President Biden to Mumbai to chide officials for putting up barriers to trade.