[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-seo-400663-105":3,"detail-sidebar-cat-0-en-105":80,"doc-detail-400663-en":130},{"code":4,"msg":5,"data":6},0,"ok",{"site_id":7,"language":8,"slug":9,"title":10,"keywords":11,"description":12,"schema_data":13,"social_meta":73,"head_meta":75,"extra_data":77,"updated_unix":79},105,"en","on-demand-dosing-of-hiv-preexposure-prophylaxis-for-women-has-their-time-finally-come","On-Demand Dosing of HIV Preexposure Prophylaxis for Women: Has Their Time Finally Come?","","Editorial commentary evaluates whether on-demand oral PrEP could become a viable option for women amid limited evidence for the 2–1–1 regimen. It contrasts established daily, injectable, and newly approved oral choices with the unmet need for women who prefer oral dosing or fewer daily doses. Using modeled pharmacokinetic/pharmacodynamic data from tissue concentrations and in vitro protection targets, the commentary argues the approach supports further assessment. It also highlights modeling challenges and adherence evidence gaps.",{"@graph":14,"@context":72},[15,34,55],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/healthcare/","Healthcare",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/on-demand-dosing-of-hiv-preexposure-prophylaxis-for-women-has-their-time-finally-come/400663/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":49,"encodingFormat":47,"isAccessibleForFree":50,"interactionStatistic":51},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/on-demand-dosing-of-hiv-preexposure-prophylaxis-for-women-has-their-time-finally-come/400663.png","ImageObject",300,407,{"name":42,"@type":43},"jay","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-10-29","2026-09-27",true,{"@type":52,"interactionType":53,"userInteractionCount":33},"InteractionCounter",{"@type":54},"ViewAction",{"@type":56,"mainEntity":57},"FAQPage",[58,64,68],{"name":59,"@type":60,"acceptedAnswer":61},"What gap does the editorial identify in on-demand PrEP for women?","Question",{"text":62,"@type":63},"It notes that no studies have been powered to demonstrate efficacy of on-demand dosing in women, even though the 2–1–1 regimen has shown effectiveness in men who have sex with men.","Answer",{"name":65,"@type":60,"acceptedAnswer":66},"How does the editorial describe the on-demand dosing regimen?",{"text":67,"@type":63},"It presents 2–1–1 dosing as taking two F/TDF tablets 2–24 hours before sex, plus one tablet each at 24 and 48 hours after sex.",{"name":69,"@type":60,"acceptedAnswer":70},"What is the role of the modeled tissue pharmacokinetic/pharmacodynamic approach?",{"text":71,"@type":63},"It explains that modeled tissue drug concentrations linked to in vitro cellular protection were used to simulate multi-day on-demand regimens and estimate the proportion of profiles meeting the 90% effective concentration across days post-sex.","https://schema.org",{"og:url":32,"og:type":74,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":76,"canonical":32},"index,follow",{"doc_id":78,"site_id":7},400663,1790763197,{"code":4,"msg":81,"data":82},"success",[83,87,91,95,100,105,109,114,119,122,126],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":84,"show_sort_weight":85,"slug":86},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":88,"show_sort_weight":89,"slug":90},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":92,"show_sort_weight":93,"slug":94},"Exam",70,"exam",{"id":96,"doc_module":4,"doc_module_name":25,"category_name":97,"show_sort_weight":98,"slug":99},5,"Comic",60,"comic",{"id":101,"doc_module":4,"doc_module_name":25,"category_name":102,"show_sort_weight":103,"slug":104},6,"Technology",50,"technology",{"id":106,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":107,"slug":108},7,40,"healthcare",{"id":110,"doc_module":4,"doc_module_name":25,"category_name":111,"show_sort_weight":112,"slug":113},8,"Research & Report",30,"research-report",{"id":115,"doc_module":4,"doc_module_name":25,"category_name":116,"show_sort_weight":117,"slug":118},9,"Religion & Spirituality",20,"religion-spirituality",{"id":117,"doc_module":4,"doc_module_name":25,"category_name":120,"show_sort_weight":117,"slug":121},"World Cup","world-cup",{"id":123,"doc_module":4,"doc_module_name":25,"category_name":124,"show_sort_weight":123,"slug":125},10,"Lifestyle","lifestyle",{"id":127,"doc_module":4,"doc_module_name":25,"category_name":128,"show_sort_weight":96,"slug":129},19,"General","general",{"code":4,"msg":81,"data":131},{"doc_id":78,"user_id":132,"nickname":42,"user_avatar":133,"doc_module":4,"category_id":106,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":33,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":30,"language":139,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":12,"update_tm":143,"read_time":110,"preview_page_count":4},3985747858866,"https://ap-avatar.wpscdn.com/davatar_a8503ba1806abce46bf441b54a3ca4cd","The Journal of Infectious Diseases  \nEDITORIAL COMMENTARY  \nOn-Demand Dosing of HIV Preexposure Prophylaxis for Women: Has Their Time Finally Come?  \nSusan P. Buchbinder1, and Peter L. Anderson2  \n1San Francisco Department of Public Health, University of California, San Francisco, California, USA; and 2Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado, USA  \nKeywords. PrEP; preexposure prophylaxis; F/TDF; on-demand; 2–1–1; women.  \nHuman immunodeficiency virus (HIV- 1)/AIDS remains the leading cause of death worldwide among women of reproductive age [ 1]. Preexposure prophylaxis (PrEP) has been shown to significantly reduce the risk of HIV acquisition in women, particularly when adherence is high [2–4] . However, current clinical guidelines recommend only 4 systemic PrEP options for women: daily coformulated emtricitabine/tenofovir disoproxil fumarate (F/TDF) [5], injectable cabotegravir administered bimonthly [5], injectable lenacapavir administered semiannually [6], and, most recently, daily F/tenofoviralafenamide (F/TAF) [6] . On-demand PrEP taken as a 2–1–1 regimen (2 F/TDF tablets 2–24 hours before sex, and 1 tablet each 24 and 48 hours after sex) has been shown to be effective in men who have sex with men (MSM) [7], but there have been no studies powered for efficacy to date of on-demand dosing for women, despite 10 years having passed  \nReceived 11 September 2025; accepted 29 September 2025; published online 9 December 2025  \nCorrespondence: Susan P. Buchbinder, MD, Bridge HIV, San Francisco Department of Public Health, 25 Van Ness Avenue, Suite 100, San Francisco, CA 94102-6033 (susan. [buchbinder@sfdph.org](buchbinder@sfdph.org)) .  \nThe Journal of Infectious Diseases®  \n© The Author(s) 2025. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@ [oup.com](oup.com) for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact [journals.permissions@oup.com](journals.permissions@oup.com). [https://doi.org/10.1093/infdis/jiaf507](https://doi.org/10.1093/infdis/jiaf507)  \nsince the original efficacy study in MSM was published. Although widespread excitement exists about long-acting PrEP agents, some women do not want injectables [8] or need or would like oral regimens delivered less frequently than daily [9]. An on-demand oral regimen would allow women demedicalized PrEP delivery that could simultaneously overcome some of the societal and structural barriers, such as stigma and relationship power dynamics, that have so severely limited PrEP uptake and persistence among women to date. Evidence from the contra  \nceptive literature underscores the importance of method choice, with greater availability of options linked to increased contraceptive uptake, increased persistence, and better health outcomes [ 10].  \nThe time is long overdue to assess ondemand regimens of oral PrEP for women. In this issue of The Journal of Infectious Diseases, Engel and colleagues present modeled data in support of on-demand PrEP dosing for women from an established pharmacokinetic/pharmacodynamic tissue model of F/TDF for PrEP [ 11]. Using data from their published in vitro/ in vivo model in which concentrations  \nof the parent and active metabolites of F/TDF and corresponding endogenous nucleotides in female genital tract tissue were linked to cellular protection from an in vitro assay [ 12], they simulated several 3- and 4-day on-demand regimens with F/TDF to determine the proportion of predicted profiles achieving or exceeding the 90% effective concentration  \n(EC90) at 5, 7, and 10 days post-sex. For rectal exposures, their previous analysis reported that > 80% of the predicted profiles achieved the EC90 for 10 days. They chose the 5-and 7-day ","cbCaijcwPb6PmCOi","https://ap.wps.com/l/cbCaijcwPb6PmCOi","pdf",303567,"English","# Editorial Commentary\n## On-demand oral PrEP rationale for women\n## Current PrEP options and evidence gaps\n## Modeling approach and EC90-based simulations\n## Challenges in estimating tissue effectiveness and adherence\n## Implications for future dosing studies","[{\"question\":\"What gap does the editorial identify in on-demand PrEP for women?\",\"answer\":\"It notes that no studies have been powered to demonstrate efficacy of on-demand dosing in women, even though the 2–1–1 regimen has shown effectiveness in men who have sex with men.\"},{\"question\":\"How does the editorial describe the on-demand dosing regimen?\",\"answer\":\"It presents 2–1–1 dosing as taking two F/TDF tablets 2–24 hours before sex, plus one tablet each at 24 and 48 hours after sex.\"},{\"question\":\"What is the role of the modeled tissue pharmacokinetic/pharmacodynamic approach?\",\"answer\":\"It explains that modeled tissue drug concentrations linked to in vitro cellular protection were used to simulate multi-day on-demand regimens and estimate the proportion of profiles meeting the 90% effective concentration across days post-sex.\"}]","On-Demand Dosing of HIV Preexposure Prophylaxis for Women: Has Their Time Finally Come? | PDF",1790513025]