RESUMEN
Ritonavir is a potent, orally bioavailable inhibitor of HIV-1 protease. Our investigators undertook a retrospective study to compare the effectiveness of ritonavir (600mg twice daily) associated with 2 reverse transcriptase inhibitors (RTIs) in 38 patients in 3 situations. Group I patients previously treated with 2 RTIs, Group II treatment-naive patients, and Group III patients previously treated with 2 RTIs and saquinavir. Routine hematological and biochemical studies, HIV-1 viremia, and CD4+ lymphocyte counts were performed before and after ritonavir. In Group I, the median of HIV-1 RNA plasma levels decreased from 4.8 to 3.4 log(10) copies/mL, in Group II from 5.9 to 2.9 log(10) copies/mL, and in Group III from 5.2 to 4.1 log(10) copies/mL. (p=0.003, p=0.014, p=0.002, respectively, Wilcoxon signed rank test). The median increases of CD4(+) cells occurred as follows: in Group I from 173 to 282 cells/mm(3), in Group II from 92 to 254 cell/mm(3), and in Group III from 68 to 133 cell/mm(3) (p=0.002, p=0.008, p<0.001, respectively, Wilcoxon signed rank test). In Group II the mean weight increased from 55.2 +/-14.3 kg to 59.4+/-15.7 kg and, in Group III, from 62.2+/-10.5 kg to 67.5+/-12 kg (p = 0.026, p = 0.002, respectively, paired T test). Patients in Group I presented no weight gain. Mild reversible hypertriglyceridemia occurred in 6 of 38 patients. The results of this study showed that ritonavir is a good choice for treatment naive patients and as a sequential option, not only after 2 RTIs, but also after a 3 drug regimen with saquinavir.