The following drug information is obtained from various newswires, published
medical journal articles, and medical conference presentations.
Approved on November 17, 1995
Epivir (also referred to as 3TC) and AZT are members of the
nucleoside analogue class of drug compounds, which both interfere
with the replication of HIV, the virus that causes AIDS.
The 3TC/AZT approval was based on data from four clinical trials
enrolling approximately 1,000 HIV-infected adults who received
either the combined 3TC/AZT therapy, 3TC as a single therapy, AZT
as a single therapy, or AZT and ddC (Roche Company's anti-AIDS
nucleoside analogue, which received accelerated approval in
The trials showed subjects treated with the 3TC/AZT combination
sustained higher increases of CD4 cells than subjects on the other
three regimens. On average, CD4 cell counts in subjects on the
3TC/AZT combination increased by 30 to 50 cells above the levels at
the start of the 24-week trials.
Adverse effects were similar to those associated with other
nucleoside analogue drugs: nausea, diarrhea, anemia, low white
blood cells, pancreatitis (especially in children who had received
prior nucleoside analogue therapy), and neuropathy. Some of the
more severe adverse reactions required withdrawal from therapy.
3TC has been studied in humans since April 1991. Since October
1993, the drug has been available to subjects outside of controlled
clinical trials under an open-label protocol. More than 35,000
subjects have received the drug under this expanded program, which
allows access to promising drugs for serious diseases prior to
3TC was granted an accelerated approval, a regulatory mechanism
which allows FDA to grant early marketing status for a product
based on laboratory markers such as CD4 cell counts (a reflection
of immune system strength) rather than on clinical endpoints such
as delay in death or reduction in opportunistic infections.
Clinical benefit must eventually be demonstrated for products
receiving accelerated approval. Trials designed to demonstrate the
clinical benefit of the 3TC/AZT treatment regimen are currently