title: Does Adherence Change When No One is Looking? Comparing Announced and Unannounced Tenofovir Levels in a PrEP Trial.
abstract: Differences between unannounced and announced tenofovir levels as measures of PrEP adherence are not well understood. In an ancillary adherence study involving one urban site (Kampala) and two rural sites (Kabwohe and Tororo) from the Partners PrEP study, 268 specimen pairs from chronologically proximal clinic and home visits were tested for plasma tenofovir levels. Comparing clinic and home specimens, 89 versus 89 % were classified as detectable (>0.31 ng/ml; p = 0.77), 87 versus 86 % as recent dosing (>10 ng/ml; p = 0.80), and 82 versus 80 % as steady-state (>40 ng/ml; p = 0.44). Mean difference between announced and unannounced drug levels, adjusted for specimen collection time was 3.2 ng/ml (p = 0.50) for Kabwohe, 23.2 ng/ml (p = 0.003) for Kampala and -3.3 ng/ml p = 0.69) for Tororo. In the setting of high adherence, plasma tenofovir levels tested at the clinic were categorically similar as levels tested at home; however, differences were seen between urban and rural settings.
authors.affiliation: Department of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda. nmusinguzi@gmail.com.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Musinguzi
authors.affiliation: Infectious Diseases Institute, Makerere University, Kampala, Uganda.
authors.forename: Timothy
authors.initials: T
authors.lastname: Muwonge
authors.affiliation: Department of Global Health, University of Washington, Seattle, WA, USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Thomas
authors.affiliation: Department of Global Health, University of Washington, Seattle, WA, USA.|Department of Medicine, University of Washington, Seattle, WA, USA.|Department of Epidemiology, University of Washington, Seattle, WA, USA.
authors.forename: Jared M
authors.initials: JM
authors.lastname: Baeten
authors.affiliation: Department of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda.|Massachusetts General Hospital, Center for Global Health, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.|Department of Global Health and Populations, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Bangsberg
authors.affiliation: Massachusetts General Hospital, Center for Global Health, Boston, MA, USA.|Harvard Medical School, Boston, MA, USA.
authors.forename: Jessica E
authors.initials: JE
authors.lastname: Haberer
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D016903:Drug Monitoring; D004359:Drug Therapy, Combination; D000068679:Emtricitabine / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000517:prevention & control* / Q000523:psychology; D006801:Humans; D008297:Male; D055118:Medication Adherence / Q000523:psychology*; D065129:Pre-Exposure Prophylaxis; D012648:Self Care / Q000523:psychology*; D012747:Sexual Partners; D000068698:Tenofovir / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D014454:Uganda
chemical_list: D019380:Anti-HIV Agents; D000068698:Tenofovir; D000068679:Emtricitabine
keywords: Announced adherence; Emtricitabine; Prep; Tenofovir; Unannounced adherence