Switching from Various Triple HAART Regimens to Lopinavir/Ritonavir Monotherapy in Selected Patients

Long term adverse events and expense associated with HAART have led to an interest in simplified therapy. What could be simpler than monotherapy? Lopinavir/ritonavir monotherapy is an attractive option due to its potency and high genetic barrier.

The current study is a 48 week interim analysis of a 96 week, open-label, randomized study, to assess the feasibility of using LPV/r monotherapy in patients with undetectable viral load after being on HAART for at least 6 months, and without previous virologic failure. Subjects were randomized (1:1) to either switch from triple HAART to LPV/r monotherapy or to maintain their current triple HAART regimen.

Results

60 patients were enrolled.

Baseline characteristics were similar in both groups.

At week 48, by intention-to-treat analysis, 26/30 (86.7%) subjects in the monotherapy arm and 25/30 (83.3%) subjects in the control group had a VL of <80 copies/mL.

There was one virologic failure (defined as VL > 1000 cp/ml) in each arm.

One subject in the monotherapy arm experienced VF with a VL of 1,200 copies/mL at wk 48.

Genotypic resistance results are pending; however, this subject was intensified with TDF + 3TC at the time of VF and subsequently re-suppressed to < 80 copies/mL.

One subject in the control arm experienced VF at wk 36.

Resistance testing showed no resistance-associated mutations. No statistically significant differences were found with regards to changes in CD4 counts, serum cholesterol, and anthropometric measures.

There were no grade 3 or 4 lab abnormalities observed.

One subject in the monotherapy group discontinued due to diarrhea.

Two subjects in the control group underwent regimen changes due to drug-related toxicities.

Based on these results, the authors conclude, "Switching from various triple HAART regimens to LPV/r monotherapy, in patients who were virologically suppressed and without a history of previous virologic failure, was effective, safe and well tolerated through 48 weeks."

Federal University of Rio de Janeiro (UFRJ), Projeto Praça Onze, Rio de Janeiro, Brazil, Hospital Geral de Nova Iguaçu, Infectious Diseases, Rio de Janeiro, Brazil, Abbott Laboratories, Chicago, United States.

Reference
E P Nunes, M S Oliveira, MMTB Almeida, and others. 48-week efficacy and safety results of simplification to single agent lopinavir/ritonavir (LPV/r) regimen in patients suppressed below 80 copies/mL on HAART - the KalMo study. 16th International AIDS Conference. August 13-18, 2006. Toronto, Canada. Abstract TUAB0103.