First-line ritonavir/indinavir 100/800 mg twice daily plus nucleoside reverse transcriptase inhibitors in a German multicentre study: 48-week results

Abstract

Objectives. To evaluate safety and efficacy of the protease inhibitor combination ritonavir/indinavir 100/800 mg twice daily plus 2-3 nucleoside reverse transcriptase inhibitors (NRTI) in antiretroviral-naive patients. Methods. Within this open-label, uncontrolled multicentre trial, antiretroviral-naive patients (n = 57) with median baseline HIV-RNA of 308 000 copies/mL (range 170-3.01 million copies/mL) and median CD4 cell count of 50 cells/μL (range 0-853 cells/μL) were started on 2-3 NRTIs plus ritonavir/indinavir 100/800 mg twice daily. CD4 cell counts and HIV-RNA were determined at weeks 0, 4, 8, 12, 16, 20, 24 and 48. Statistical analysis was performed on treatment as well as intent-to-treat. Results. Viral load decreased by a median of 3.79 log10 copies/mL (range 2.0-4.60 log10 copies/mL) until week 48. At week 48, 23/57 (40%, intent-to-treat) patients showed a viral load ≤ 80 copies/mL. In parallel, median CD4 cell counts increased by a median of 149 cells/μL (range -60-420 cells/μL). Median triglycerides and cholesterol increased from baseline 160 mg/dL (range 33-364 mg/dL) to 218 mg/dL (range 110-527 mg/dL) at week 48 and from 166 mg/dL (range 63-262 mg/dL) to 233 mg/dL (range 95-359 mg/dL), respectively. Twenty-seven of fifty-seven patients (47%) discontinued study medication, 19 (33%) due to nephrolithiasis. Two patients changed their antiretroviral regimen after failing virologically. Conclusion. Ritonavir/indinavir 100/800 mg twice daily appears to be effective up to 48 weeks despite high baseline viraemia and low CD4 cell count in antiretroviral-naive patients. However, discontinuation due to adverse events, especially nephrotoxicity, is frequent and limits treatment duration. Therefore, extra hydration appears inevitable with this combination.