Study of efavirenz over 96 weeks shows durability, efficacious regimen

Results from 48-96 weeks essentially same

Recent results from the Daily Antiretroviral Therapy (DART 1) trial show promising results for antiretroviral-naïve patients.

The 96-week study results from 65 patients who were treated with the combination of once-daily efavirenz (600 mg), lamivudine (300 mg), and didanosine (400 mg) showed that the rates of patients achieving HIV-1 RNA viral loads of less than 400 copies were essentially the same as the previous 48-week results.1

"For the 96-week study, the HIV RNA of less than 400 copies in an intent-to-treat analysis was 74 percent, and in the treated analysis, which only included patients who were able to remain on the study, it was 100 percent," says Edwin DeJesus, MD, medical director of the Orlando Immunology Center in Orlando, FL, lead author of the study.

"When we looked at an analysis of less than 50 copies, the intent to treat group had 68 percent, and the treated analysis group was at 92 percent," DeJesus says.

The intent to treat group included responses from patients who had discontinued the study for various reasons, DeJesus explains.

"Once a patient took a dose of medication, the patient was counted," he says.

The once-daily regimen was a simple one of 3 pills, chosen for its convenience and safety, DeJesus says.

"We want to be able to provide future patients with options that are less toxic and lead to less chronic adverse events," DeJesus explains. "This regimen provides a good alternative for that."

The phase IV, open-label, single arm study followed patients prospectively for nearly 2 years, looking at both efficacy and safety in patients who were new to antiretroviral treatment.

"It’s important to study the durability of these regimens," DeJesus says.

The patients had baseline viral loads of greater than 1000 copies, and their baseline CD4 cell counts were equal to or greater than 100, he says.

"These patients couldn’t have an AIDS diagnosis, but they could have had it in the past, as long as they were antiretroviral naïve," DeJesus says.

"The beauty of these results were when you compare the week 48 to week 96, the results were essentially the same," DeJesus says. "All of the patients who continued the study continued from week 48 to 96, so there was no virologic breakthrough from week 48 to 96."

This means that once patients took the once-daily medication regimen they continued to respond, and they had no virologic breakthroughs of having a HIV viral load of less than 400 copies on 2 consecutive occasions.1

"The main take-home message of this study is that there was no discontinuation on the second year of follow-up due to virologic failure, breakthrough virus, or lack of efficacy," DeJesus says. "The importance of this study is it gives us another simple option with 3 pills, once a day."

Reference

  1. DeJesus E, et al. Efficacy and Safety of a Once-Daily Efavirenz-Based Regimen for Treatment Naive HIV Subjects: 96-Week Results from the DART I Trial. Presented at the 10th European AIDS Conference/The European AIDS Clinical Society, Nov. 17-20, 2005, in Dublin, Ireland. Poster: PE7.3/3.