Zerit is indicated for the treatment of adults with advanced HIV infection who are intolerant of approved therapies with proven clinical benefit or who have experienced significant clinical or immunologic deterioration while receiving these therapies or for whom such therapies are contraindicated.

10,438 subjects participated in a randomized, double-blind, 12-week clinical trial comparing Zerit to zidovudine, another treatment for HIV infection. Subjects receiving Zerit had a mean increase in CD4+ cell count from baseline to week 12, while subjects continuing on zidovudine had a mean decrease of CD4+ cell count.

The major clinical toxicity of Zerit is peripheral neuropathy. This adverse event occurred in 15% to 21% of subjects in the controlled trials. Neuropathy is characterized by numbness, tingling, or pain in the feet and hands.

Zerit inhibits the replication of HIV in human cells in vitro by two known mechanisms. First, it inhibits HIV reverse transcriptase, the process by which HIV-infected DNA is created from RNA. Second, it inhibits viral DNA synthesis by causing DNA chain termination; natural elongation of DNA chains is unable to occur.

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