January 10, 2003
The following information was noted by the FDA in its approval announcement: In a clinical study conducted in 783 treatment-naive, HIV-infected individuals Zerit XR was comparable to the previously approved twice daily formulation of Zerit. In this randomized, controlled study, participants were randomized to either the extended release or standard formulation, in combination with Epivir and Sustiva. The proportion of people with HIV-RNA (viral load levels) below 400 copies at 48 weeks was 79 percent and 76 percent for the extended release and immediate release-containing regimens, respectively. For viral load under 50, the response rates were 55 percent and 57 percent for the new and old formulations, respectively. The tolerability and safety profile of the new once daily, extended release formulation is comparable to that of the previously approved twice-daily formulation.
This adds one more drug to the list of once-a-day FDA-approved antiretrovirals. The other drugs include Videx, Videx EC, Sustiva, Epivir, and Viread. It is expected that the new once-a-day protease, Atazanavir, will be approved sometime in the next few months. For more information on once-a-day HIV treatments, see the article in the Fall 2002 STEP Perspective, "Once-Daily Antiretroviral Options."