Predicting HIV care costs using CD4 counts from clinical trials

Objective: To predict the effects of a new antiretroviral agent on the costs of care in a US HIV care setting. Methods: Recent data on costs of patient care by CD4 count from 2 US cohorts (the HIV Research Network cohort and patients receiving primary care at the University of Alabama at Birmingham HIV clinic) were combined with CD4 count data from the POWER trials of the protease inhibitor darunavir. Patients in the POWER trials received either darunavir plus low-dose ritonavir (darunavir/r) or selected control protease inhibitors. The effects of rising CD4 counts with darunavir/r 600/100 mg twice daily on healthcare costs were predicted by using the US cohort data and published US antiretroviral drug prices. Results: In the POWER trials, the overall cost of antiretroviral treatment including darunavir/r was $427 (1.4%) higher than that of combination treatment including control protease inhibitors. However, this increase may be offset by lower predicted costs of HIV care, leading to predicted net savings in overall costs of HIV treatment and care of $3613 per person-year based on data from the HIV Research Network cohort and $2836 per person-year based on data from the University of Alabama cohort. The prediction of cost savings is limited to the 12-month duration of the trial. Conclusion: By raising the CD4 count, new antiretrovirals could lower healthcare costs for HIV-infected people.This type of analysis could be used for other antiretrovirals, for a short-term assessment of overall budget impact.