Retrospective longitudinal cohort study with 36 HIV naïve-treatment patients, who started therapy with lopinavir/ritonavir or efavirenz (LPV/r or EFZ), follow-up of 36 months. Primary endpoint: virological success (HIV RNA <50 copies/mL) in the first six months and at the end of the study.

Background: Either LPV/r or EFZ plus a two nucleoside reverse-transcriptase inhibitors (NRTIs) are recommended by the current guidelines all around the world as the main background drugs for initial therapy of human immunodeficiency virus type 1 (HIV-1) infection. This indication is based in results of clinical trials, but patients who participate in these studies usually are greatly motivated to continue their prescribed regimen, and can be different from the "real life". Therefore, clinical practice often cannot reproduce published results.

Methods: A retrospective longitudinal cohort study was performed with 36 naïve-treatment patients, who started therapy with LPV/r or EFZ, with follow-up of 36 months. The primary endpoint was virological success (HIV RNA <50 copies/mL) in the first six months and at the end of the study. Effectiveness was examined comparing time to virological failure and CD4 recovery.

Inclusion Criteria:

• HIV-1 infected naive-treatment patients

Exclusion Criteria:

• use of Anti-Retroviral Agents in the past