A Pilot Study of Efficacy and Safety of Standard Dose of Lopinavir/Ritonavir in Combination with one Nonnucleoside Reverse Transcriptase Inhibitor and one Nucleoside Reverse Transcriptase Inhibitor in well Virology Suppressed HIV Infected Adults

Abstract

Background : Highly active antiretroviral therapy leads to long life of HIV-infected adults. More patients have co-morbid diseases which cause intolerance of nucleoside reverse transcriptase inhibitor (NRTI) toxicity. Due to limitation of available drug in Thailand, adjusting regimen to nonnucleoside reverse transcriptase inhibitor (NNRTI) plus boosted protease inhibitor is another option.

Objectives: To study the virological control and trough concentration (Ctrough) of lopinavir (LPV) in a combined regimen of one NNRTI, one NRTI and standard dose of lopinavir/ritonavir (LPV/rtv).

Material and Methods: This study was a 52-week prospective clinical trial. Eligible patients were HIV - infected adults with plasma HIV RNA (pVL) < 50 copies/mL, age > 18 years, no history of LPV resistance and received a combined treatment of one NNRTI, one NRTI and LPV/rtv for at least 3 months. Patients with LPV/rtv 500mg/125 mg were adjusted to 400mg/100 mg. the other combined drugs, 1 NNRTI and 1 NRTI were continued. The primary outcome was virological control (pVL<50 copies/mL). Secondary outcome was Ctrough of LPV > 1 mg/L.

Results: Between November 2013 and April 2014, a total of 12 patients were screened and enrolled in this study. Seven patients received LPV/rtv 500 mg/125 mg before enrollment and five patients received LPV/rtv 400 mg/100 mg. Seven patients on nevirapine (NVP) and five patients on efavirenz (EFV). Eleven patients on lamivudine and one patient on tenofovir. Eleven of 12 patients had pVL< 50 copies/mL and their Ctrough of LPV > 1 mg/L.

Conclusion: NVP or EFV plus standard dose of LPV/rtv in Thai HIV infected adults with well virological suppress had efficacy in virological control with enough level of Ctrough of LPV.