title: Predicting direct costs of HIV care during the first year of darunavir-based highly active antiretroviral therapy using CD4 cell counts: evidence from POWER.
abstract: BACKGROUND
  Given the association between CD4 cell counts and HIV-related morbidity/mortality, new antiretroviral therapies could potentially lower the direct costs of HIV care by raising CD4 cell counts.
  
  
  OBJECTIVE
  To predict the effects of the ritonavir-boosted, HIV protease inhibitor (PI) darunavir on the direct costs of care, while accounting for CD4 cell counts, during the first year of therapy in highly treatment-experienced, HIV-infected adults in different healthcare settings.
  
  
  METHODS
  The mean annual per-patient cost of darunavir/ritonavir (DRV/r) and control PI-based highly active antiretroviral therapy (HAART) was calculated from the proportional use of antiretroviral agents in the DRV/r and control PI arms of the pooled POWER 1 and 2 trials, applying drug-acquisition costs for five healthcare settings. Non-antiretroviral-related costs by CD4 cell count, derived from non-interventional studies in the same settings, were applied to the POWER data (proportion of patients with CD4 cell counts in different strata at week 48) to estimate mean annual non-antiretroviral-related costs per patient in patients receiving DRV/r or control PI-based HAART during year 1.
  
  
  RESULTS
  Across all settings, the mean annual per-patient cost of DRV/r-based treatment was 2-19% higher than that of control PI-based therapy during the first year of therapy. By raising CD4 cell counts, however, DRV/r-based regimens were predicted to lower mean annual non-antiretroviral-related costs by 16-38% compared with control PI-based therapy. When combined, the total annual per-patient cost of HIV care during the first year of therapy was estimated to be 7% lower in the DRV/r compared with the control PI arm using US data, 8% lower using Swedish data, budget neutral using UK and Belgian data and 5% higher using Italian data.
  
  
  CONCLUSIONS
  Darunavir-based HAART may lower non-antiretroviral-related costs compared with control PI-based therapy in highly treatment-experienced, HIV-infected patients during the first year of therapy by improving patients' CD4 cell counts. These costs could partly/fully offset the increased acquisition cost of DRV/r in this patient population over the same period.
authors.affiliation: Department of Pharmacology, University of Liverpool, Liverpool, UK and Tibotec BVBA, Mechelen, Belgium.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Hill
authors.forename: Kelly
authors.initials: K
authors.lastname: Gebo
authors.forename: Lindsay
authors.initials: L
authors.lastname: Hemmett
authors.forename: Mickael
authors.initials: M
authors.lastname: Löthgren
authors.forename: Gabriele
authors.initials: G
authors.lastname: Allegri
authors.forename: Erik
authors.initials: E
authors.lastname: Smets
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023241:Antiretroviral Therapy, Highly Active / Q000191:economics*; D018791:CD4 Lymphocyte Count / Q000191:economics; D017322:Clinical Trials, Phase II as Topic; D000069454:Darunavir; D016527:Drug Costs; D005060:Europe; D006678:HIV; D015658:HIV Infections / Q000188:drug therapy / Q000191:economics*; D017320:HIV Protease Inhibitors / Q000191:economics / Q000627:therapeutic use; D015497:HIV-1; D017048:Health Care Costs; D006801:Humans; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D016032:Randomized Controlled Trials as Topic; D019438:Ritonavir / Q000191:economics* / Q000627:therapeutic use; D013449:Sulfonamides / Q000191:economics* / Q000627:therapeutic use; D014481:United States; D055815:Young Adult
chemical_list: D017320:HIV Protease Inhibitors; D013449:Sulfonamides; D019438:Ritonavir; D000069454:Darunavir