Who's the biggest HIV drug seller of all?

Who's the Big Kahuna of HIV drugs? If you said GlaxoSmithKline (NYSE: GSK) or Abbott Laboratories (NYSE: ABT), you're wrong. It's Gilead Sciences (NASDAQ: GILD), at least according to sales figures compiled by Reuters.

Gilead drugs occupy the top two slots in a global ranking of HIV meds by sales. Truvada sits on top with $2.49 billion in 2009 sales; Atripla (a Gilead/Bristol-Myers Squibb med) is second with $2.38 billion; and Viread is in seventh place with $668 million. Add it up and you'll get more than $5.5 billion.

Even the big GlaxoSmithKline-Pfizer partnership, ViiV, doesn't come close to that. The venture's Epzicom came in at fifth place with $855 million, while Combivir nabbed eighth place with $665 million and Epivir came in 10th with $542 million. Of course, GSK and Pfizer are hoping that their combination pipeline will eventually boost ViiV drugs up in the rankings.

Merck, Bristol-Myers, Abbott Laboratories and Johnson & Johnson all have drugs in the top 10.

- read the Reuters ranking