The Cost and Intermediate Cost-Effectiveness of a Randomized Control Trial Delivering U=U Messaging to Increase HIV...

South African men have lower HIV testing uptake than their female counterparts, leading to lower antiretroviral treatment (ART) uptake and higher HIV-related mortality. A recent cluster-randomized trial in a high HIV prevalence area in Cape Town showed that relaying the "undetectable equals untransmittable" (U=U) message to South African men increased their HIV testing uptake compared to issuing standard testing invitations. We conducted an economic analysis based on this trial to inform decision-making regarding implementing U=U messaging in routine public-sector HIV care.

We analyzed the mean cost of the U=U intervention and its intermediate cost-effectiveness over the control arm. Costs were estimated from trial expenditure data in 2020 South African rand (ZAR), converted using March 2020 US$ exchange rates. Shared trial costs were allocated to each arm based on participant volume or days of operation; capital costs, including the creation of the U=U message via human-centered design workshops, were annualized over 8 years. In a second scenario, trial cost was adjusted for potential implementation in routine care.

Peer promoters delivered 504 U=U invitations to test for HIV over 7 intervention days and 544 standard invitations over 5 control days in March 2020. Compared with standard invitations, men who received U=U messaging had 60% increased odds of getting tested for HIV. The average trial cost was $5.40 per U=U message delivered ($2.35 after adjustment for routine implementation), $388.47 per person testing HIV-positive ($168.99 adjusted), and $906.44 per person initiating ART ($394.31 adjusted). Within trial costs, staff, overhead, and research costs were the largest allocations, with each accounting for 20% to 30% of total costs. After routine implementation adjustment, the costs of message creation via human-centered design workshops, personnel (peer promoters, research staff), and supplies were the largest allocations. Cost of U=U messaging per person confirmed HIV-positive and initiating ART was lower than conventional HIV testing messaging and at the lower end of cost ranges of HIV self-test distribution models targeted at men ($62 to $7,936 per person confirmed positive and $117 to $8,198 per person initiating ART) established in previous work.

Delivering tailored U=U messaging can increase HIV testing and ART uptake among men while saving costs over standard untargeted HIV testing messaging and other HIV self-test distribution models.