Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa:  A modelling analysis

Jack Stone; Rutendo Bothma; Gabriela B.  Gomez; Robyn Eakle; Christinah Mukandavire; Hasina Subedar; Hannah Fraser; Marie-Claude Boily; Sheree Schwartz; Jenny Coetzee; Kennedy Otwombe; Minja Milovanovic; Stefan D. Baral; Leigh F Johnson; Willem Daniel Francois  Venter; Helen Rees; Peter T Vickerman

doi:10.1002/jia2.26063

Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: A modelling analysis

Jack Stone^*, Rutendo Bothma, Gabriela B. Gomez, Robyn Eakle, Christinah Mukandavire, Hasina Subedar, Hannah Fraser, Marie-Claude Boily, Sheree Schwartz, Jenny Coetzee, Kennedy Otwombe, Minja Milovanovic, Stefan D. Baral, Leigh F Johnson, Willem Daniel Francois Venter, Helen Rees, Peter T Vickerman

^*Corresponding author for this work

Research output: Contribution to journal › Article (Academic Journal) › peer-review

4 Citations (Scopus)

Abstract

Introduction
In 2016, South Africa (SA) initiated a national program to scale-up pre-exposure prophylaxis (PrEP) among female sex workers (FSWs), with ~20,000 PrEP initiations among FSW (~14% of FSW) by 2020. We evaluated the impact and cost-effectiveness of this program, including future scale-up scenarios and potential detrimental impact of the COVID-19 pandemic.

Methods
A compartmental HIV transmission model for SA was adapted to include PrEP. Using estimates on self-reported PrEP adherence from a national study of FSW (67.7%) and the Treatment and Prevention for FSWs (TAPS) PrEP demonstration study in SA (80.8%), we down-adjusted TAPS estimates for the proportion of FSWs with detectable drug levels (adjusted range: 38.0-70.4%). The model stratified FSW by low (undetectable drug; 0% efficacy) and high adherence (detectable drug; 79.9%; 95%CI:67.2-87.6% efficacy). FSWs can transition between adherence levels, with lower loss-to-follow-up among highly adherent FSWs (aHR:0.58; 95%CI:0.40-0.85; TAPS data). The model was calibrated to monthly data on the national scale-up of PrEP among FSWs over 2016-2020, including reductions in PrEP initiations during 2020. The model projected the impact of the current program (2016-2020) and the future impact (2021-2040) at current coverage or if initiation and/or retention are doubled. Using published cost data, we assessed the cost-effectiveness (healthcare provider perspective; 3% discount rate; time horizon 2016-2040) of current PrEP provision.

Results
Calibrated to national data, model projections suggest 2.1% of HIV-negative FSWs were currently on PrEP in 2020, with PrEP preventing 0.45% (95% credibility interval, 0.35-0.57%) of HIV infections among FSWs over 2016-2020 or 605 (444-840) infections overall. Reductions in PrEP initiations in 2020 possibly reduced infections averted by 18.57% (13.99-23.29). PrEP is cost-saving, with $1.42 (1.03-1.99) of ART costs saved per dollar spent on PrEP. Going forward, existing coverage of PrEP will avert 5,635 (3,572-9,036) infections by 2040. However, if PrEP initiation and retention doubles, then PrEP coverage increases to 9.9% (8.7-11.6%) and impact increases 4.3-times with 24,114 (15,308-38,107) infections averted by 2040.

Conclusions
Our findings advocate for the expansion of PrEP to FSWs throughout SA to maximize its impact. This should include strategies to optimise retention and should target women in contact with FSW services.

Original language	English
Article number	e26063
Number of pages	12
Journal	Journal of the International AIDS Society
Volume	26
Issue number	2
DOIs	https://doi.org/10.1002/jia2.26063
Publication status	Published - 20 Feb 2023

Bibliographical note

Funding Information:
Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID-674-A-12-00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID-OAA-A-14-00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS-Free Generation in Senegal (AID-OAA-A-13-00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161-01A1 and R01NR016650-04S1. PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol - http://www.bristol.ac.uk/acrc/

Funding Information:
Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID‐674‐A‐12‐00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID‐OAA‐A‐14‐00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS‐Free Generation in Senegal (AID‐OAA‐A‐13‐00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161‐01A1 and R01NR016650‐04S1.

Funding Information:
The content is solely the responsibility of the authors and does not necessarily represent the official views of any of the funding agencies. GBG is currently employed by Sanofi Pasteur. Sanofi Pasteur did not provide funding for this work and had no role in study design, data collection, data analysis, data interpretation or writing of the report. RE is currently employed by USAID which occurred after the original project ended. This article was made possible by the support of the American people through the United States Agency for International Development (USAID) under the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). The contents of this article are the sole responsibility of the authors and do not necessarily reflect the views of USAID, PEPFAR or the United States Government. This work was supported, in whole or in part, by the Bill & Melinda Gates Foundation [OPP1084416]. Under the grant conditions of the Foundation, a Creative Commons Attribution 4.0 Generic License has already been assigned to the Author Accepted Manuscript version that might arise from this submission.

Funding Information:
HF has received an honorarium from MSD unrelated to this research. PV has received unrestricted research funding from Gilead unrelated to this work.

Funding Information:
PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol ‐ http://www.bristol.ac.uk/acrc/

Publisher Copyright:
© 2023 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.

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Cite this

Stone, J., Bothma, R., Gomez, G. B., Eakle, R., Mukandavire, C., Subedar, H., Fraser, H., Boily, M.-C., Schwartz, S., Coetzee, J., Otwombe, K., Milovanovic, M., Baral, S. D., Johnson, L. F., Venter, W. D. F., Rees, H., & Vickerman, P. T. (2023). Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: A modelling analysis. Journal of the International AIDS Society, 26(2), Article e26063. https://doi.org/10.1002/jia2.26063

@article{929f85ffd1354939b8ee27332a902da9,

title = "Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: A modelling analysis",

abstract = "IntroductionIn 2016, South Africa (SA) initiated a national program to scale-up pre-exposure prophylaxis (PrEP) among female sex workers (FSWs), with ~20,000 PrEP initiations among FSW (~14% of FSW) by 2020. We evaluated the impact and cost-effectiveness of this program, including future scale-up scenarios and potential detrimental impact of the COVID-19 pandemic. MethodsA compartmental HIV transmission model for SA was adapted to include PrEP. Using estimates on self-reported PrEP adherence from a national study of FSW (67.7%) and the Treatment and Prevention for FSWs (TAPS) PrEP demonstration study in SA (80.8%), we down-adjusted TAPS estimates for the proportion of FSWs with detectable drug levels (adjusted range: 38.0-70.4%). The model stratified FSW by low (undetectable drug; 0% efficacy) and high adherence (detectable drug; 79.9%; 95%CI:67.2-87.6% efficacy). FSWs can transition between adherence levels, with lower loss-to-follow-up among highly adherent FSWs (aHR:0.58; 95%CI:0.40-0.85; TAPS data). The model was calibrated to monthly data on the national scale-up of PrEP among FSWs over 2016-2020, including reductions in PrEP initiations during 2020. The model projected the impact of the current program (2016-2020) and the future impact (2021-2040) at current coverage or if initiation and/or retention are doubled. Using published cost data, we assessed the cost-effectiveness (healthcare provider perspective; 3% discount rate; time horizon 2016-2040) of current PrEP provision.ResultsCalibrated to national data, model projections suggest 2.1% of HIV-negative FSWs were currently on PrEP in 2020, with PrEP preventing 0.45% (95% credibility interval, 0.35-0.57%) of HIV infections among FSWs over 2016-2020 or 605 (444-840) infections overall. Reductions in PrEP initiations in 2020 possibly reduced infections averted by 18.57% (13.99-23.29). PrEP is cost-saving, with $1.42 (1.03-1.99) of ART costs saved per dollar spent on PrEP. Going forward, existing coverage of PrEP will avert 5,635 (3,572-9,036) infections by 2040. However, if PrEP initiation and retention doubles, then PrEP coverage increases to 9.9% (8.7-11.6%) and impact increases 4.3-times with 24,114 (15,308-38,107) infections averted by 2040. ConclusionsOur findings advocate for the expansion of PrEP to FSWs throughout SA to maximize its impact. This should include strategies to optimise retention and should target women in contact with FSW services. ",

author = "Jack Stone and Rutendo Bothma and Gomez, {Gabriela B.} and Robyn Eakle and Christinah Mukandavire and Hasina Subedar and Hannah Fraser and Marie-Claude Boily and Sheree Schwartz and Jenny Coetzee and Kennedy Otwombe and Minja Milovanovic and Baral, {Stefan D.} and Johnson, {Leigh F} and Venter, {Willem Daniel Francois} and Helen Rees and Vickerman, {Peter T}",

note = "Funding Information: Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID-674-A-12-00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID-OAA-A-14-00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS-Free Generation in Senegal (AID-OAA-A-13-00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161-01A1 and R01NR016650-04S1. PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol - http://www.bristol.ac.uk/acrc/ Funding Information: Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID‐674‐A‐12‐00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID‐OAA‐A‐14‐00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS‐Free Generation in Senegal (AID‐OAA‐A‐13‐00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161‐01A1 and R01NR016650‐04S1. Funding Information: The content is solely the responsibility of the authors and does not necessarily represent the official views of any of the funding agencies. GBG is currently employed by Sanofi Pasteur. Sanofi Pasteur did not provide funding for this work and had no role in study design, data collection, data analysis, data interpretation or writing of the report. RE is currently employed by USAID which occurred after the original project ended. This article was made possible by the support of the American people through the United States Agency for International Development (USAID) under the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). The contents of this article are the sole responsibility of the authors and do not necessarily reflect the views of USAID, PEPFAR or the United States Government. This work was supported, in whole or in part, by the Bill & Melinda Gates Foundation [OPP1084416]. Under the grant conditions of the Foundation, a Creative Commons Attribution 4.0 Generic License has already been assigned to the Author Accepted Manuscript version that might arise from this submission. Funding Information: HF has received an honorarium from MSD unrelated to this research. PV has received unrestricted research funding from Gilead unrelated to this work. Funding Information: PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol ‐ http://www.bristol.ac.uk/acrc/ Publisher Copyright: {\textcopyright} 2023 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.",

year = "2023",

month = feb,

day = "20",

doi = "10.1002/jia2.26063",

language = "English",

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journal = "Journal of the International AIDS Society",

issn = "1758-2652",

publisher = "BioMed Central",

number = "2",

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Stone, J, Bothma, R, Gomez, GB, Eakle, R, Mukandavire, C, Subedar, H, Fraser, H, Boily, M-C, Schwartz, S, Coetzee, J, Otwombe, K, Milovanovic, M, Baral, SD, Johnson, LF, Venter, WDF, Rees, H & Vickerman, PT 2023, 'Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: A modelling analysis', Journal of the International AIDS Society, vol. 26, no. 2, e26063. https://doi.org/10.1002/jia2.26063

Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: A modelling analysis. / Stone, Jack; Bothma, Rutendo; Gomez, Gabriela B. et al.
In: Journal of the International AIDS Society, Vol. 26, No. 2, e26063, 20.02.2023.

Research output: Contribution to journal › Article (Academic Journal) › peer-review

TY - JOUR

T1 - Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa

T2 - A modelling analysis

AU - Stone, Jack

AU - Bothma, Rutendo

AU - Gomez, Gabriela B.

AU - Eakle, Robyn

AU - Mukandavire, Christinah

AU - Subedar, Hasina

AU - Fraser, Hannah

AU - Boily, Marie-Claude

AU - Schwartz, Sheree

AU - Coetzee, Jenny

AU - Otwombe, Kennedy

AU - Milovanovic, Minja

AU - Baral, Stefan D.

AU - Johnson, Leigh F

AU - Venter, Willem Daniel Francois

AU - Rees, Helen

AU - Vickerman, Peter T

N1 - Funding Information: Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID-674-A-12-00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID-OAA-A-14-00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS-Free Generation in Senegal (AID-OAA-A-13-00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161-01A1 and R01NR016650-04S1. PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol - http://www.bristol.ac.uk/acrc/ Funding Information: Funding for this project primarily came from the Bill and Melinda Gates Foundation [OPP1084416] and the United States Agency for International Development [AID‐674‐A‐12‐00034]. Additionally, funding was also provided by a supplement to the Johns Hopkins University Center for AIDS Research, a National Institutes of Health (NIH) funded programme (P30AI094189) with support specifically from the Office of AIDS Research (OAR). The original model development received support from the Linkages across the Continuum of HIV Services for Key Populations Affected by HIV project (LINKAGES, Cooperative Agreement AID‐OAA‐A‐14‐00045) and the parent study HIV Prevention 2.0 (HP2): Achieving an AIDS‐Free Generation in Senegal (AID‐OAA‐A‐13‐00089). The supplement, LINKAGES and HP2 received support from the United States Agency for International Development (USAID) and the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). JC was supported by the South African Medical Research Council through its Division of Research Capacity Development under the Research Capacity Development Initiative (RCDI) programme. Funding was also received in part by the Wellcome Trust [214204/A/18/Z]. SB and SS were funded by R01MH121161‐01A1 and R01NR016650‐04S1. Funding Information: The content is solely the responsibility of the authors and does not necessarily represent the official views of any of the funding agencies. GBG is currently employed by Sanofi Pasteur. Sanofi Pasteur did not provide funding for this work and had no role in study design, data collection, data analysis, data interpretation or writing of the report. RE is currently employed by USAID which occurred after the original project ended. This article was made possible by the support of the American people through the United States Agency for International Development (USAID) under the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). The contents of this article are the sole responsibility of the authors and do not necessarily reflect the views of USAID, PEPFAR or the United States Government. This work was supported, in whole or in part, by the Bill & Melinda Gates Foundation [OPP1084416]. Under the grant conditions of the Foundation, a Creative Commons Attribution 4.0 Generic License has already been assigned to the Author Accepted Manuscript version that might arise from this submission. Funding Information: HF has received an honorarium from MSD unrelated to this research. PV has received unrestricted research funding from Gilead unrelated to this work. Funding Information: PV and HF also acknowledge support from the National Institute of Health Research Health Protection Research Unit in Behavioural Science and Evaluation at the University of Bristol (NIHR200877). MCB acknowledges funding from the MRC Centre for Global Infectious Disease Analysis (reference MR/R015600/1), jointly funded by the UK Medical Research Council (MRC) and the UK Foreign, Commonwealth & Development Office (FCDO), under the MRC/FCDO Concordat agreement and is also part of the European & Developing Countries Clinical Trials Partnership phase 2 (EDCTP2) programme supported by the European Union. This work was carried out using the computational facilities of the Advanced Computing Research Centre, University of Bristol ‐ http://www.bristol.ac.uk/acrc/ Publisher Copyright: © 2023 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.

PY - 2023/2/20

Y1 - 2023/2/20

N2 - IntroductionIn 2016, South Africa (SA) initiated a national program to scale-up pre-exposure prophylaxis (PrEP) among female sex workers (FSWs), with ~20,000 PrEP initiations among FSW (~14% of FSW) by 2020. We evaluated the impact and cost-effectiveness of this program, including future scale-up scenarios and potential detrimental impact of the COVID-19 pandemic. MethodsA compartmental HIV transmission model for SA was adapted to include PrEP. Using estimates on self-reported PrEP adherence from a national study of FSW (67.7%) and the Treatment and Prevention for FSWs (TAPS) PrEP demonstration study in SA (80.8%), we down-adjusted TAPS estimates for the proportion of FSWs with detectable drug levels (adjusted range: 38.0-70.4%). The model stratified FSW by low (undetectable drug; 0% efficacy) and high adherence (detectable drug; 79.9%; 95%CI:67.2-87.6% efficacy). FSWs can transition between adherence levels, with lower loss-to-follow-up among highly adherent FSWs (aHR:0.58; 95%CI:0.40-0.85; TAPS data). The model was calibrated to monthly data on the national scale-up of PrEP among FSWs over 2016-2020, including reductions in PrEP initiations during 2020. The model projected the impact of the current program (2016-2020) and the future impact (2021-2040) at current coverage or if initiation and/or retention are doubled. Using published cost data, we assessed the cost-effectiveness (healthcare provider perspective; 3% discount rate; time horizon 2016-2040) of current PrEP provision.ResultsCalibrated to national data, model projections suggest 2.1% of HIV-negative FSWs were currently on PrEP in 2020, with PrEP preventing 0.45% (95% credibility interval, 0.35-0.57%) of HIV infections among FSWs over 2016-2020 or 605 (444-840) infections overall. Reductions in PrEP initiations in 2020 possibly reduced infections averted by 18.57% (13.99-23.29). PrEP is cost-saving, with $1.42 (1.03-1.99) of ART costs saved per dollar spent on PrEP. Going forward, existing coverage of PrEP will avert 5,635 (3,572-9,036) infections by 2040. However, if PrEP initiation and retention doubles, then PrEP coverage increases to 9.9% (8.7-11.6%) and impact increases 4.3-times with 24,114 (15,308-38,107) infections averted by 2040. ConclusionsOur findings advocate for the expansion of PrEP to FSWs throughout SA to maximize its impact. This should include strategies to optimise retention and should target women in contact with FSW services.

AB - IntroductionIn 2016, South Africa (SA) initiated a national program to scale-up pre-exposure prophylaxis (PrEP) among female sex workers (FSWs), with ~20,000 PrEP initiations among FSW (~14% of FSW) by 2020. We evaluated the impact and cost-effectiveness of this program, including future scale-up scenarios and potential detrimental impact of the COVID-19 pandemic. MethodsA compartmental HIV transmission model for SA was adapted to include PrEP. Using estimates on self-reported PrEP adherence from a national study of FSW (67.7%) and the Treatment and Prevention for FSWs (TAPS) PrEP demonstration study in SA (80.8%), we down-adjusted TAPS estimates for the proportion of FSWs with detectable drug levels (adjusted range: 38.0-70.4%). The model stratified FSW by low (undetectable drug; 0% efficacy) and high adherence (detectable drug; 79.9%; 95%CI:67.2-87.6% efficacy). FSWs can transition between adherence levels, with lower loss-to-follow-up among highly adherent FSWs (aHR:0.58; 95%CI:0.40-0.85; TAPS data). The model was calibrated to monthly data on the national scale-up of PrEP among FSWs over 2016-2020, including reductions in PrEP initiations during 2020. The model projected the impact of the current program (2016-2020) and the future impact (2021-2040) at current coverage or if initiation and/or retention are doubled. Using published cost data, we assessed the cost-effectiveness (healthcare provider perspective; 3% discount rate; time horizon 2016-2040) of current PrEP provision.ResultsCalibrated to national data, model projections suggest 2.1% of HIV-negative FSWs were currently on PrEP in 2020, with PrEP preventing 0.45% (95% credibility interval, 0.35-0.57%) of HIV infections among FSWs over 2016-2020 or 605 (444-840) infections overall. Reductions in PrEP initiations in 2020 possibly reduced infections averted by 18.57% (13.99-23.29). PrEP is cost-saving, with $1.42 (1.03-1.99) of ART costs saved per dollar spent on PrEP. Going forward, existing coverage of PrEP will avert 5,635 (3,572-9,036) infections by 2040. However, if PrEP initiation and retention doubles, then PrEP coverage increases to 9.9% (8.7-11.6%) and impact increases 4.3-times with 24,114 (15,308-38,107) infections averted by 2040. ConclusionsOur findings advocate for the expansion of PrEP to FSWs throughout SA to maximize its impact. This should include strategies to optimise retention and should target women in contact with FSW services.

U2 - 10.1002/jia2.26063

DO - 10.1002/jia2.26063

M3 - Article (Academic Journal)

C2 - 36807874

SN - 1758-2652

VL - 26

JO - Journal of the International AIDS Society

JF - Journal of the International AIDS Society

IS - 2

M1 - e26063

ER -