Background: ANRS IPERGAY showed the efficacy of on demand PrEP with TDF/FTC in preventing HIV acquisition among MSM.
Methods: A prospective economic evaluation was performed during the trial from the healthcare system perspective to determine the cost of PrEP per HIV-infection averted in the TDF/FTC arm. Both hospital and non-hospital resources were considered. Costs for counseling were added. Drugs (TDF/FTC and drugs for STIs), tests (for HIV and STIs), visits and hospital admissions were valued with the national tariff and based on their mean use during the trial (15 tablets of TDF/FTC per month). Robustness of results was tested by sensitivity analyses. The incremental cost-effectiveness ratio (ICER) of PrEP per HIV-infection averted was calculated for one year and compared to the yearly and lifetime cost of one HIV-infection in France (€20,170 and € 535,000 respectively).
Results: The trial enrolled 400 participants and found that the number needed to treat for one year to prevent one HIV-infection was 17.6. The cost of counseling was 690 € per person-year. The total one-year costs of PrEP were €4,004 per participant, of which 78% were drug costs (€500 for 30 tablets of TDF/FTC). PrEP ICER was €70,470 per infection averted. Using TDF/FTC costs of €60 for 30 tablets, the one-year cost was €1,253 per patient and the ICER was €22,052 per infection averted, similar to the yearly cost of treating HIV-infection. Sensitivity analyses in figure 1 show the contrubtion of drug costs and NNT results on the ICER.

sensitivity analysis of the ICER at current and low drug prices
[sensitivity analysis of the ICER at current and low drug prices]

Conclusions: In France, the ICER of on demand PrEP in MSM with TDF/FTC at the current price is higher than the cost of treating a patient with HIV-infection for one year but much lower than the lifetime cost of HIV-infection. Using the lower cost of TDF/FTC however, PrEP becomes cost-neutral on a yearly basis.