Pre-Exposure Prophylaxis (PrEP) Adherence Monitoring Using Dried Blood Spots

Summary

The primary objective of this study is to define the mean, variance, and dose proportionality for tenofovir-diphosphate(TFV-DP) in dried blood spots resulting from 33%, 67%, and 100% of daily dosing with 200mg emtricitabine and 300mg of tenofovir disoproxil fumarate (as Truvada®). With this information, a model will be established to predict adherence rates to TFV-DP using DBS. Forty-eight healthy HIV-uninfected adult participants who are at low risk for HIV infection will be randomized to one of 6 sequences consisting of two directly observed dosing regimens, 33%/67%, 33%/100%, 67%/33%, 67%/100%, 100%/33%, and 100%/67% with each dose regimen lasting approximately 12 weeks, separated by an approximately 12 week washout period. DBS will be collected at regular intervals, including during the washout. The hypothesis of the study is that levels of TFV-DP in DBS will predict adherence rates in the preceding 1-3 months.

Timeline

Start

2014-04

Primary completion

2016-11

Completion

2017-01

Publications

• Background Anderson PL, Liu AY, Castillo-Mancilla JR, Gardner EM, Seifert SM, McHugh C, Wagner T, Campbell K, Morrow M, Ibrahim M, Buchbinder S, Bushman LR, Kiser JJ, MaWhinney S. Intracellular Tenofovir-Diphosphate and Emtricitabine-Triphosphate in Dried Blood Spots following Directly Observed Therapy. Antimicrob Agents Chemother. 2017 Dec 21;62(1):e01710-17. doi: 10.1128/AAC.01710-17. Print 2018 Jan.
• Ibrahim ME, Castillo-Mancilla JR, Yager J, Brooks KM, Bushman L, Saba L, Kiser JJ, MaWhinney S, Anderson PL. Individualized Adherence Benchmarks for HIV Pre-Exposure Prophylaxis. AIDS Res Hum Retroviruses. 2021 Jun;37(6):421-428. doi: 10.1089/AID.2020.0108. Epub 2020 Dec 10.
• Grant RM, Pellegrini M, Defechereux PA, Anderson PL, Yu M, Glidden DV, O'Neal J, Yager J, Bhasin S, Sevelius J, Deutsch MB. Sex Hormone Therapy and Tenofovir Diphosphate Concentration in Dried Blood Spots: Primary Results of the Interactions Between Antiretrovirals And Transgender Hormones Study. Clin Infect Dis. 2021 Oct 5;73(7):e2117-e2123. doi: 10.1093/cid/ciaa1160.
• Koss CA, Liu AY, Castillo-Mancilla J, Bacchetti P, McHugh C, Kuncze K, Morrow M, Louie A, Seifert S, Okochi H, MaWhinney S, Gandhi M, Anderson PL. Similar tenofovir hair concentrations in men and women after directly observed dosing of tenofovir disoproxil fumarate/emtricitabine: implications for preexposure prophylaxis adherence monitoring. AIDS. 2018 Sep 24;32(15):2189-2194. doi: 10.1097/QAD.0000000000001935.
• Castillo-Mancilla J, Seifert S, Campbell K, Coleman S, McAllister K, Zheng JH, Gardner EM, Liu A, Glidden DV, Grant R, Hosek S, Wilson CM, Bushman LR, MaWhinney S, Anderson PL. Emtricitabine-Triphosphate in Dried Blood Spots as a Marker of Recent Dosing. Antimicrob Agents Chemother. 2016 Oct 21;60(11):6692-6697. doi: 10.1128/AAC.01017-16. Print 2016 Nov.

Drugs

Indications

No indication recorded.