Background: 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 antiretroviral therapy (ART)-naïve and pretreated but protease inhibitor (PI)-naïve patients.
Methods: This was a multicenter, prospective, open-label, 48-week observational cohort study. Tolerability assessments included changes in liver enzymes and lipid levels from baseline to week 48. Efficacy assessments included changes in the proportion of patients with HIV-1 RNA <50 and <400 copies/ml, and changes in CD4 cell count from baseline to week 48.
Results: The analysis included 275 ART-naïve and 179 pretreated but PI-naïve patients. The proportion of ART-naïve patients achieving <50 copies/ml by 48 weeks was 53.1% by intent-to-treat (ITT) analysis and 67.3% using last observation carried forward (LOCF) analysis. In pretreated but PI-naïve patients, the proportions achieving <50 copies/ml by 48 weeks were 53.1% (ITT) and 70.4% (LOCF). The median increase in CD4 count at week 48 was +174 cells/mm3 (interquartile range [IQR] 86, 265) in the ART-naïve group and +100 cells/mm3 (IQR 0, 209) in the pretreated but PI-naïve group (p < 0.01 for both; LOCF). Drug-related adverse events were reported in 7.6% of ART-naïve and 2.8% of pretreated but PI-naïve patients. Treatment with SQV/r was stopped in 21.5% of ART-naïve and 17.9% of pretreated but PI-naïve patients (due to side effects in 3.3% and 2.8%, respectively). There were no clinically relevant changes in liver enzyme levels. Overall, the total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein levels increased to week 48, although the levels remained within normal ranges in the majority of patients.
Conclusions: The results of this observational cohort study of treatment with the 500-mg tablet formulation of SQV are consistent with high efficacy and tolerability results seen in controlled studies of SQV/r. This analysis confirms that SQV/r is effective and well tolerated in ART-naïve and pretreated but PI-naïve patients in 'real-world' clinical settings.