Single and multiple dose pharmacokinetics of maraviroc in saliva, semen, and rectal tissue of healthy HIV-negative men.

BACKGROUND: Antiretroviral pharmacology in seminal plasma (SP) and rectal tissue (RT) may provide insight into antiretroviral resistance and the prevention of sexual transmission of human immunodeficiency virus (HIV). Saliva may be of utility for noninvasively measuring adherence. METHODS: A pharmacokinetic study was performed in 12 HIV-negative men receiving maraviroc 300 mg twice daily for 8 days. Seven time-matched pairs of blood plasma (BP) and saliva samples were collected over 12 h on day 1 (PK1) and days 7 and 8 (PK2). One RT sample from each subject was collected during PK1 and PK2. Two SP samples were collected from each subject during PK1, and 6 SP samples were collected from each subject during PK2. RESULTS: SP AUCs were ∼50% lower than BP. However, protein binding in SP ranged from 4% to 25%, resulting in protein-free concentrations >2-fold higher than BP. RT AUCs were 7.5- to 26-fold higher than BP. Maraviroc saliva AUCs were ∼70% lower than BP, but saliva concentrations correlated with BP (r(2) = 0.58). CONCLUSIONS: More pharmacologically available maraviroc was found in SP than BP. High RT concentrations are promising for preventing rectal HIV acquisition. Saliva correlation with BP suggests that this may be useful for monitoring adherence. CLINICAL TRIALS REGISTRATION: NCT00775294.

Gastric cancer and the high combination prevalence of host cytokine genotypes and Helicobacter pylori in Honduras.

BACKGROUND & AIMS: Inflammatory cytokine polymorphisms are associated with gastric adenocarcinoma in Helicobacter pylori-infected patients in Europe and Asia. We investigated the cytokine profile in the Latino population, specifically Honduras, a high-incidence region, and the use of the combination prevalence of H pylori and genotypes in identifying high-risk populations. METHODS: A population-based case-control study identified 170 incident gastric cancer cases and 162 healthy village controls. Interleukin (IL)-Ibeta-511, IL-1RN, IL-10-1082, and tumor necrosis factor-alpha-308 genotypes were determined. We define the combination prevalence index (CPI) as the product of H pylori and IL-1beta-511T+ genotype prevalence in healthy subjects. Medline identified gastric cancer studies to facilitate country-specific CPI calculations. RESULTS: In healthy, population-based Honduran controls, IL-1beta-511T+ prevalence was 81% (95% confidence interval, 75%-87%; CT, 57%; TT, 25%), which was among the highest reported. IL-10-1082A+ prevalence was 93% (95% confidence interval, 88%-97%), mirroring Asian populations. Seventeen percent were homozygous for both proinflammatory cytokines (TT/AA), with increased risk among cases (odds ratio, 2.6; 95% confidence intervals, 1.0-6.8). Tumor necrosis factor-alpha polymorphisms were nearly absent. Endemic H pylori infection (85%) was confirmed. Importantly, the CPI association with country incidence is highly significant (P = .0057), based on 16 global populations and Honduras. Sensitivity analysis confirms a robust CPI. CONCLUSIONS: The CPI, based on IL-1beta genotypes, has a strong association with country-specific gastric cancer incidence. The CPI correlation supports the chronic inflammation carcinogenesis model, and may explain the geographic variation. We report a novel cytokine profile in Honduras that mirrors Asian populations and explains the high incidence rates. This may have dyspepsia management and screening implications for the growing US Latino population.