Safety and efficacy after switch to a saquinavir-containing antiretroviral regimen in protease inhibitor pretreated HIV-positive patients.

Objective: the RAINBOW survey is a multinational observational study assessing the tolerability and efficacy of ritonavir-boosted saquinavir (SQV/r), using the 500 mg film-coated SQV formulation, in routine clinical practice. This analysis presents data from the German subgroup of protease inhibitor (PI)-pretreated, but SQV-naive patients.
Methods: multicenter, prospective, open-label, 48 week cohort study. Efficacy assessments included the proportion of patients with HIV-1 RNA <50 and <400 copies/mL and changes in CD4 cell count from baseline to week 48. Tolerability assessments included changes in liver enzymes and lipid levels from baseline to week 48.
Results: a total of 426 patients were included in the analysis. The proportion of patients with HIV RNA levels <50 copies/mL at week 48 was 60.3 % (compared with 31.7% at switch to SQV/r) (intent-to-treat, last observation carried forward analysis). After 48 weeks, median CD4 count increased by +61 cells/mm3 from baseline (p<0.01) and 60.3% of patients achieved HIV-1 RNA <50 copies/mL. Median changes in fasting triglyceride levels (stratified according to baseline level) at week 48 were: +14 mg/dL (IQR -8; 57) for patients with baseline triglyceride <200 mg/dL; -50 mg/dL (IQR -139; 0) for baseline triglyceride 200-750 mg/dL, and -656 mg/dL (IQR -1024; 0) for baseline triglyceride >750 mg/dL (p<0.01 for all). Median changes in fasting total cholesterol (TC) levels (stratified according to baseline) were +16 mg/dL (IQR -3; 43) for patients with baseline TC <200 mg/dL (p<0.01), -3 mg/dL (IQR -25; 25) for baseline TC 200-300 mg/dL (p = 0.4), and -47 mg/dL (IQR -87; -4) for baseline TC >300 mg/dL (p<0.01). No significant changes in liver enzymes or bilirubin were observed. SQV treatment was discontinued in 22% of patients, 6% due to side effects.
Conclusions: these data confirm the efficacy and tolerability of SQV/r in PI-experienced, SQV-naive patients treated in a real-life clinical setting. Of particular relevance are the improvements in triglycerides and TC levels observed in patients with baseline grade III-IV elevations.