AIDS Treatment News logo      

September 21, 2009

GS-9350 boosts atazanavir just as well as ritonavir

"GS-9350, a new pharmacoenhancer being developed by Gilead Sciences, equals ritonavir (Norvir) as a booster of blood levels of atazanavir (Reyataz), researchers reported last week at the 49th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) l in San Francisco. ...

"Atazanavir levels were 'bioequivalent', or functionally similar, in people taking 150 mg GS-9350 and those taking 100 mg ritonavir. The atazanavir concentration across the dosing interval (known as area under the curve) was equal with both boosting agents, and the maximum atazanavir concentration (known as Cmax) was also similar. Half-life, or how long the drug remains in the body, was comparable. Using the 100 mg dose of GS-9350, however, produced lower atazanavir levels.

"Nine participants discontinued the study early, five of them due to adverse events. Most side-effects were mild and no serious problems were reported, including liver toxicity or clinically relevant heart rhythm changes. However, three people taking GS-9350 stopped early due to skin rash, which resolved after the drug was discontinued."

Read more in Aidsmap, September 21, 2009.