Imperial College London


Faculty of MedicineSchool of Public Health

Professor of Mathematical Epidemiology



+44 (0)20 7594 3263mc.boily




LG26Norfolk PlaceSt Mary's Campus






BibTex format

author = {Mitchell, KM and Dimitrov, D and Hughes, J and Xia, F and Donnell, D and Amico, R and Bokock, K and CHITWARAKORN, A and Bekker, L-G and Holtz, T and Mannheimer, S and Grant, R and Boily, MC},
doi = {10.1097/QAD.0000000000001766},
journal = {AIDS},
pages = {809--818},
title = {In what circumstances could non-daily pre-exposure prophylaxis for HIV substantially reduce program costs?},
url = {},
volume = {32},
year = {2018}

RIS format (EndNote, RefMan)

AB - Objectives:To review the main factors influencing the costs of nondaily oral pre-exposure prophylaxis (PrEP) with tenofovir ( emtricitabine). To estimate the costreductions possible with nondaily PrEP compared with daily PrEP for different popula-tions (MSM and heterosexual populations).Design:Systematic review and data triangulation.Methods:We estimated the required number of tablets/person/week for dosing regi-mens used in the HPTN 067/ADAPT (daily/time-driven/event-driven) and IPERGAY (on-demand) trials for different patterns of sexual intercourse. Using trial data, andbehavioural and cost data obtained through systematic literature reviews, we estimatedcost savings resulting from tablet reductions for nondaily versus daily oral PrEP,assuming 100% adherence.Results:Among different populations being prioritized for PrEP, the median reportednumber of days of sexual activity varied between 0 and 2days/week (0–1.5days/weekfor MSM, 1–2days/week for heterosexual populations). With 100% adherence and twoor fewer sex-days/week, HPTN 067/ADAPT nondaily regimens reduced the number oftablets/week by more than 40% compared with daily PrEP. PrEP program costs werereduced the most in settings with high drug costs, for example, by 66–69% with event-driven PrEP for French/US populations reporting on average one sex-day/week.Conclusion:Nondaily oral PrEP could lower costs substantially (>50%) compared withdaily PrEP, particularly in high-income countries. Adherence and efficacy data areneeded to determine cost-effectiveness.
AU - Mitchell,KM
AU - Dimitrov,D
AU - Hughes,J
AU - Xia,F
AU - Donnell,D
AU - Amico,R
AU - Bokock,K
AU - Bekker,L-G
AU - Holtz,T
AU - Mannheimer,S
AU - Grant,R
AU - Boily,MC
DO - 10.1097/QAD.0000000000001766
EP - 818
PY - 2018///
SN - 0269-9370
SP - 809
TI - In what circumstances could non-daily pre-exposure prophylaxis for HIV substantially reduce program costs?
UR -
UR -
VL - 32
ER -