In 2001, the US Food and Drug Administration approved a new HIV medication called tenofovir disoproxil fumarate (TDF). Patient advocates hailed the decision, noting that it represented the first novel antiviral agent to get the green light after the FDA turned down a similar drug two years earlier. But a lot changes in a decade. For one thing, the maker of TDF, Gilead Sciences of Foster City, California, has a newer, better formulation of tenofovir, called tenofovir alafenamide (TAF). Meanwhile, patient advocates at the International AIDS Society Conference in Kuala Lumpur this week are crying foul that the company isn’t working on a stand-alone version of TAF and plans to sell it only in expensive combination pills.