First up tomorrow is a review of Gilead's Truvada as a prophylactic to prevent infection by HIV. In clinical trials, Truvada reduced the risk of getting HIV by 44% to 75%. A drug to prevent a disease requires a cleaner side-effect profile than one that treats a disease, since many people taking the drug as a prophylactic will never get the disease. Fortunately, Truvada has been used for a long time to treat HIV, so the safety risk is well established and fairly tolerable.
While a recommendation from the committee and an eventual FDA approval seems likely, obtaining the ability to market Truvada as a prophylactic isn't going to be worth all that much to Gilead. Truvada is fairly expensive, and it seems likely that most insurance companies will be unwilling to cover the cost to use it as a prophylactic.
On Friday, the panel will review Gilead's HIV quad pill. The efficacy has looked pretty good, with reductions in virus levels comparable to Atripla -- a three-in-one pill -- or to a combination of Abbott Labs'
The Quad will compete against Gilead's own drugs, but the company owns all four drugs in the Quad and doesn't have to share revenues like it does with Atripla, which contains a Bristol-Myers drug, and Complera, which contains a drug from Johnson & Johnson
The prospects for a positive advisory panel vote and an eventual FDA approval of the Quad are high, but don't expect much of an increase in the stock price over the binary events, since investors are already expecting an approval.