Investigating zero transmission of HIV in the MSM population: a UK modelling case study

Table 3 Base case and future scenario key parameter inputs

Key parameter	Scenario input values^a
Key parameter	Base case	Combination prevention	Combination prevention, 98% TasP	Combination prevention, 99% TasP	Aspirational combination prevention	NHS-commissioned PrEP base case^b	NHS-commissioned PrEP combination prevention
Rate of PrEP uptake	0.08%^c	0.25%	0.25%	0.25%	0.45%	0.08%^c	0.25%
Proportion of MSMLWH diagnosed within three months of transmission	26.00% [4]	40.00%	40.00%	40.00%	40.00%	26.00% [4]	40.00%
Annual probability of having an HIV test	22.35% [4]	40.00%	40.00%	40.00%	50.00%	22.35% [4]	40.00%
Probability of starting treatment within six months of diagnosis	95.17% [31]	98.00%	98.00%	98.00%	98.00%	95.17% [31]	98.00%
Probability of starting treatment within three months of diagnosis	78.00% [6]	90.00%	90.00%	90.00%	95.00%	78.00% [6]	90.00%
TasP	97% [16]	97%	98%	99%	99%	97% [16]	99%

Footnotes: ^aFuture scenario input values are implemented as a linear increase from the 2020 base case value to 2024, with the exception of the date of PrEP uptake which is implemented as a linear increase from 2020 to 2022. ^bIn the NHS-commissioned PrEP base case the number of MSM on PrEP in the first year of the model is increased from the model base case value of 24,698 (based on the number of MSM enrolled on the IMPACT trial) [16] to 50,152 (based on the number of MSM reported to be accessing PrEP through NHS specialist SHSs in 2021) [20]. ^cAssumption based on PrEP Impact trial uptake [21]. All other base case scenario inputs are based on 2019 Public Health England data. HIV: human immunodeficiency virus; MSMLWH: men who have sex with men living with HIV; NHS: National Health Service; PrEP: pre-exposure prophylaxis; TasP: treatment as prevention

ISSN: 2049-3258