We describe the safety, tolerability, and efficacy of protease inhibitor (PI) containing highly active antiretroviral therapy (HAART) among patients switching from nonnucleoside reverse transcriptase inhibitor (NNRTI)-based HAART from a clinical setting in South India. We assessed a prospective cohort of 91 HIV-infected patients with at least 12 months of clinical follow-up on second-line ritonavir-boosted PI-based therapy between August 2003 and December 2008. More than three fourths of patients met the World Health Organization (WHO) criteria for immunological failure at the time of switch. The median time to switch was 758 days. Patients demonstrated consistent increases in their CD4 counts during the first 12 months, by which time the median CD4 count was 322 cells/mm(3). The most common adverse events within the first year after switch were nausea (14.8%), lipodystrophy (10.4%), and peripheral neuropathy (7.0%). Patients switching to atazanavir (ATV)-based regimens compared to those switching to indinavir (IDV)-based regimens had similar immunological and clinical outcomes. Given the therapeutic success of using second-line PI-containing HAART after experiencing treatment failure, further efforts must be taken to expand access to second-line HAART so that more patients can benefit from these drugs.
