{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T12:38:13Z","timestamp":1793277493508,"version":"4.5.0"},"reference-count":28,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T00:00:00Z","timestamp":1789084800000},"content-version":"am","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"Protocol Safety Review Team Drs Usha Sharma"},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Lydia Soto-Torres"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Intraerythrocytic tenofovir diphosphate (TFV-DP) concentrations from emtricitabine\/tenofovir disoproxil fumarate (F\/TDF) pre-exposure prophylaxis (PrEP) measured in dried blood spots (DBS) are approximately 30\u201340% lower during pregnancy, but data on TFV-DP concentrations in peripheral blood mononuclear cells (PBMCs) are limited. We evaluated the effect of pregnancy on intracellular TFV-DP concentrations in PBMCs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Directly observed dosing of daily oral F\/TDF was administered to 18 healthy nonpregnant and 18 pregnant Kenyan women without HIV for 8 weeks. Blood for DBS and PBMC was collected weekly for nonpregnant and biweekly for pregnant women. TFV-DP concentrations in DBS and PBMCs were quantified using validated liquid chromatography-tandem mass spectrometry. Steady-state fitted TFV-DP concentrations in PBMC and DBS were compared between pregnant and nonpregnant women.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Median (IQR) age was 23 (20\u201327) years and gestational age was 16 (14\u201320) weeks for pregnant women at enrollment. Median (IQR) Cockroft Gault-estimated creatinine clearance was 131 (113\u2013146) mL\/min for nonpregnant versus 176 (154\u2013196) mL\/min for pregnant women. 1922 of 1925 (99.8%) expected doses were directly observed. Fitted steady-state median (IQR) TFV-DP concentrations in DBS were 1545 (1203, 1887) fmol\/punch in nonpregnant versus 919 (835, 1003) fmol\/punch in pregnant women [percent change: 40.5%, 95% CI (29.5%, 51.5%); P &amp;lt; .001]. Modeled steady-state geometric mean (GM) (95% CI) PBMC TFV-DP concentrations were 56.2 (48.0, 65.8) fmol\/106 cells in nonpregnant versus 47.8 (40.4, 56.5) fmol\/106 cells in pregnant women [GM ratio (95% CI): .85 (.68, 1.06); P = .15].<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Steady-state TFV-DP concentrations in PBMCs were reassuringly not meaningfully different between pregnant and nonpregnant women.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/infdis\/jiag460","type":"journal-article","created":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T11:51:40Z","timestamp":1789041100000},"source":"Crossref","is-referenced-by-count":0,"title":["Effect of Pregnancy on Intracellular Tenofovir Diphosphate Exposure and Thresholds Following Oral Emtricitabine-Tenofovir Disoproxil Fumarate Pre-Exposure Prophylaxis: A Directly Observed Dosing Study"],"prefix":"10.1093","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-7240-5412","authenticated-orcid":false,"given":"Linxuan","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Epidemiology, University of Washington , Seattle, Washington ,","place":["USA"]},{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1200-8494","authenticated-orcid":false,"given":"Peter L","family":"Anderson","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus , Aurora, Colorado ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9818-0059","authenticated-orcid":false,"given":"Samantha","family":"MaWhinney","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus , Aurora, Colorado ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matilda","family":"Saina","sequence":"additional","affiliation":[{"name":"Center for Clinical Research, Kenya Medical Research Institute , Nairobi ,","place":["Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2347-006X","authenticated-orcid":false,"given":"Nelly R","family":"Mugo","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]},{"name":"Center for Clinical Research, Kenya Medical Research Institute , Nairobi ,","place":["Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3963-1339","authenticated-orcid":false,"given":"Clare E","family":"Brown","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nina","family":"Akelo","sequence":"additional","affiliation":[{"name":"Center for Clinical Research, Kenya Medical Research Institute , Nairobi ,","place":["Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katherine","family":"Thomas","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer F","family":"Morton","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1338-2592","authenticated-orcid":false,"given":"Elex","family":"Hill","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenneth","family":"Ngure","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]},{"name":"Department of Community Health, Jomo Kenyatta University of Agriculture and Technology , Nairobi ,","place":["Kenya"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8636-4048","authenticated-orcid":false,"given":"Elena A","family":"Rechkina","sequence":"additional","affiliation":[{"name":"Department of Global Health, University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lane","family":"Bushman","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus , Aurora, Colorado 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