Purpose: To evaluate a rescue therapy involving nevirapine plus nelfinavir plus two nucleoside reverse transcriptase inhibitors (NRTIs) in patients with prior extensive antiretroviral therapy (AT) including protease inhibitors (PIs) but not nonnucleoside reverse transcriptase inhibitors (NNRTIs).
Method: Patients with failing regimens were prospectively enrolled. According to genotypic profile at baseline, two groups were identified: a highly resistant (HR) group, which included strains resistant to PI and NRTI, and a moderate nonresistant group (MR), which showed resistance only to PI or NRTI or no resistance.
Results: Twenty-two individuals were included. Average time of AT prior to enrollment was 3.7 years (range 1.4-7.6), median viral load 4.92 log(10) (interquartile range [IQR] 1.63 log(10)), and median CD4 cell count 64 cells/microL (IQR 94). After 16 weeks of treatment, seven patients (31%) achieved virological response, five of them (22.7%) with <500 c/mL (bDNA). Fourteen patients were studied for resistance. The HR group showed a poorer response than the MR group (0 vs. 7 responses; p =.034).
Conclusion: We found a virological response in 31% of our patients, and mainly in those of the MR group some presented previous intolerance. These two factors probably reflect the number of drugs included in the rescue therapy to which the patient is sensitive. Treatment history as well as genotypic resistance assays are useful in identifying patients with the best chance of responding.