Tissue Pharmacologic and Virologic Determinants of Duodenal and Rectal Gastrointestinal-Associated Lymphoid Tissue Immune Reconstitution in HIV-Infected Patients Initiating Antiretroviral Therapy

Plasma, duodenal, and rectal tissue antiretroviral therapy (ART) drug concentrations, human immunodeficiency virus (HIV) RNA and HIV DNA copy numbers, and recovery of mucosal immunity were measured before and 9 months after initiation of 3 different ART regimens in 26 subjects. Plasma and tissue HIV RNA correlated at baseline and when 9-month declines were compared, suggesting that these compartments are tightly associated. Antiretroviral tissue:blood penetration ratios were above the 50% inhibitory concentration values in almost 100% of cases. There were no correlations between drug concentrations and HIV DNA/RNA. Importantly, no evidence was found for residual viral replication or deficient tissue drug penetration to account for delayed gastrointestinal-associated lymphoid tissue immune recovery.

Lessons from maraviroc clinical trials

Evaluation of: Gulick RM, Lalezari J, Goodrich J et al. Maraviroc for previously treated patients with R5 HIV-1 infection. N. Engl. J. Med. 359, 1429-1441 (2008). Maraviroc is the first commercially available HIV chemokine receptor antagonist targeting HIV that utilizes the CCR5 chemokine receptor (R5 tropic). The Maraviroc versus Optimized Therapy in Viremic Antiretroviral Treatment-Experienced Patients (MOTIVATE) trials were two randomized, placebo-controlled studies designed to demonstrate the activity of maraviroc in triple-class-experienced HIV individuals, with a primary end point of viral load suppression at 48 weeks. Maraviroc outperformed the placebo plus optimized background (OBT) arm, and exhibited a favorable safety profile with low discontinuation rates, which equaled those of the placebo plus OBT group. The results of these trials led to maraviroc receiving regulatory approval for the treatment of HIV.