TRIZAL study: switching from successful HAART to Trizivir (abacavir-lamivudine-zidovudine combination tablet): 48 weeks efficacy, safety and adherence results.

OBJECTIVE:

To assess the antiviral efficacy, safety, and adherence in subjects who switched to Trizivir following long-term HIV-1 RNA suppression.

STUDY DESIGN:

A randomized, open-label, multicentre, 48-week comparative study in subjects who have received two nucleoside reverse transcriptase inhibitors plus a protease inhibitor or an nonnucleoside reverse transcriptase inhibitor or three nucleoside reverse transcriptase inhibitors for at least 6 months, with a history of undetectable plasma HIV-1 RNA since initiation of therapy and plasma viral load of < 50 HIV-1 RNA copies/mL at screening.

METHODS:

Subjects were randomized 1:1 to continue their current treatment or to switch to a simplified treatment with Trizivir administered twice daily. Assessments included plasma HIV-1 RNA, lymphocyte counts, clinical laboratory evaluations, adverse events, and adherence to treatment (obtained via subject self-report). Treatment failure was defined as a plasma viral load of >/= 400 HIV-1 RNA copies/mL on two consecutive occasions or premature discontinuation of randomized treatment.

RESULTS:

At week 48, the proportion of treatment failures in Trizivir arm (23/106, 22%) was noninferior to that observed in continued arm (23/103, 22%) with a treatment difference stratified by prior ART of 1.2%[-10.1; 12.5]. Incidence of adverse events was similar in both treatment groups. The incidence of possible hypersensitivity reaction in the Trizivir trade mark arm was 10%. Significant reductions in cholesterol and triglyceride plasma levels were observed in the Trizivir arm (P < 0.001 and P = 0.006, respectively).

CONCLUSION:

Switching to Trizivir offers a potent and simplified regimen with equivalent efficacy and significant improvement in lipid abnormalities compared to continued triple therapy.