Switch from raltegravir to enfuvirtide may be safe and effective for patients with multidrug resistant HIV

Between 88% and 89% of patients with multidrug-resistant HIV who continued with enfuvirtide or who switched to raltegravir reached target HIV RNA levels, according to results of a recent study.

There were 170 patients with multidrug-resistant HIV and HIV RNA levels <400 copies/mL involved in the trial. They were randomly assigned in a 1:1 ratio to maintain enfuvirtide treatment or to switch to raltegravir.

The primary endpoint was the cumulative proportion of patients with virologic failure, which the researchers defined as a confirmed HIV RNA level of ≥400 copies/mL over 24 weeks. Most of the secondary endpoints were safety-related.

Virologic failure rates were 1.2% in both groups. The difference between treatment groups (raltegravir minus enfuvirtide) with regard to intention-to-treat analysis was 0.01% (95% CI, –6.7 to 6.8).

Results of the on-treatment-analysis demonstrated a difference of 1.22% (95% CI, –5.6 to 8.1).

At the 24-week mark, 88%-89% of patients in both groups had HIV RNA levels <50 copies/mL.

There were no significant CD4 cell count changes observed in either group.

There were few grade 3-4 adverse events or laboratory abnormalities in either group. There was no difference in rates of those occurrences between the two groups.

De Castro N et al. Clin Infect Dis. 2009;49:1259-1267.