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RESEARCH ARTICLE (Open Access)

Impact of increased antiretroviral therapy use during the treatment as prevention era in Australia

Richard T. Gray https://orcid.org/0000-0002-2885-0483 A *
+ Author Affiliations
- Author Affiliations

A The Kirby Institute, UNSW Sydney, Sydney, NSW, Australia.

* Correspondence to: Rgray@kirby.unsw.edu.au

Handling Editor: Jason Ong

Sexual Health - https://doi.org/10.1071/SH23088
Submitted: 3 May 2023  Accepted: 2 June 2023   Published online: 3 July 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Background: We analysed the impact of increased antiretroviral therapy (ART) on HIV epidemiology and healthcare costs in Australia during the ‘Treatment-as-prevention’ and ‘Undetectable equals Untransmissible (U=U)’ eras.

Methods: We conducted a retrospective modelling analysis between 2009 and 2019 to calculate the potential impact of early initiation of ART and treatment-as-prevention on HIV among gay and bisexual men (GBM). The model incorporates the change in the proportion diagnosed, treated, and virally suppressed, as well as the scale-up of oral HIV pre-exposure prophylaxis (PrEP) and the change in sexual behaviour during this period. We simulated a baseline and a no ART increase scenario and conducted a costing analysis from a national health provider perspective with cost estimates in 2019 AUD.

Results: Increasing ART use between 2009 and 2019 averted an additional 1624 [95% percentile interval (PI): 1220–2099] new HIV infections. Without the increase in ART, the number of GBM with HIV would have increased from 21 907 (95% PI: 20 753–23 019) to 23 219 (95% PI: 22 008–24 404) by 2019. HIV care and treatment costs for people with HIV increased by $296 (95% PI: $235–367) million AUD (assuming no change in annual healthcare costs). This was offset by a decrease in the lifetime HIV costs (with 3.5% discounting) for those newly infected of $458 (95% PI: $344–592) million AUD, giving a net cost saving of $162 (95%: $68–273) million AUD (and a benefits-to-cost ratio of 1.54).

Conclusions: Increasing the proportion of Australian GBM on effective ART between 2009 and 2019 likely resulted in substantial reductions in new HIV infections and cost savings.

Keywords: antiretroviral therapy, cost-effectiveness, epidemiology, HIV/AIDS, mathematical models, public health, treatment as prevention.


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