A Multi-Compartment Single and Multiple Dose Pharmacokinetic Comparison of Rectally Applied Tenofovir 1% Gel and Oral Tenofovir Disoproxil Fumarate

作者:Yang Kuo Hsiung*; Hendrix Craig; Bumpus Namandje; Elliott Julie; Tanner Karen; Mauck Christine; Cranston Ross; McGowan Ian; Richardson Harman Nicola; Anton Peter A; Kashuba Angela D M
来源:PLos One, 2014, 9(10): e106196.
DOI:10.1371/journal.pone.0106196

摘要

This Phase 1, randomized, two-site (United States), double-blind, placebo-controlled study enrolled 18 sexually abstinent men and women. All received a single 300-mg dose of oral tenofovir disoproxil fumarate (TDF) and were then randomized 2: 1 to receive single and then seven daily rectal exposures of vaginally-formulated tenofovir (TFV) 1% gel or a hydroxyethyl cellulose (HEC) placebo gel. Blood, colonic biopsies and rectal and vaginal mucosal fluids were collected after the single oral TDF, the single topical TFV gel dose, and after 7 days of topical TFV gel dosing for extracellular analysis of TFV and intracellular analysis of the active metabolite tenofovir diphosphate (TFVdp) in peripheral blood mononuclear cells (PBMCs) and isolated mucosal mononuclear cells (MMC), including CD4+ and CD4-cell subsets. With a single rectal dose, TFV plasma concentrations were 24-33 fold lower and half-life was 5 h shorter compared to a single oral dose (p = 0.02). TFVdp concentrations were also undetectable in PBMCs with rectal dosing. Rectal tissue exposure to both TFV and TFVdp was 2 to 4-log(10) higher after a single rectal dose compared to a single oral dose, and after 7 daily doses, TFVdp accumulated 4.5 fold in tissue. TFVdp in rectal tissue homogenate was predictive (residual standard error, RSE = 0.47) of tissue MMC intracellular TFVdp concentration, with the CD4+ cells having a 2-fold higher TFVdp concentration than CD4-cells. TFV concentrations from rectal sponges was a modest surrogate indicator for both rectal tissue TFV and TFVdp (RSE = 0.67, 0.66, respectively) and plasma TFV (RSE = 0.38). TFV penetrates into the vaginal cavity after oral and rectal dosing, with rectal dosing leading to higher vaginal TFV concentrations (p<0.01).

  • 出版日期2014-10-28

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