title: Cost-effectiveness of combination therapy for treatment of benign prostatic hyperplasia: a model based on the findings of the Combination of Avodart and Tamsulosin trial.
abstract: OBJECTIVE
  • To evaluate the cost-effectiveness of combination therapy for benign prostatic hyperplasia (BPH) compared with alpha-blocker (AB), 5-alpha reductase inhibitor (5ARI) monotherapy or watchful waiting (WW) in male patients enrolled in the Combination of Avodart and Tamsulosin (CombAT) trial using a Norwegian economic model.
  
  
  METHODS
  • A decision analytic model was constructed to evaluate the BPH treatment regimens using point estimate base-case analyses, one-way sensitivity testing and probabilistic sensitivity analyses. • Symptom severity and acute urinary retention/transurethral resection of the prostate (AUR/TURP) event data came from the 4-year evaluation of the CombAT trial with additional data from the Medical Therapy of Prostatic Symptoms (MTOPS) trial. The model makes use of Norwegian practice pattern data and unit cost and utility estimates were taken from the published literature. • The model calculates treatment costs and utility outcomes at two time horizons: 4 years and lifetime. Incremental cost-effectiveness ratios (ICERs) were calculated using WW as the basis of comparison. Costs and health state utilities were discounted after the first year.
  
  
  RESULTS
  • At 4 years, ICER results for combination therapy are higher than AB monotherapy as a result of the higher drug cost, but the overall cost and quality-adjusted life-year (QALY) differences are small. • At the lifetime evaluation, the ICER results decrease from those at the 4-year horizon, although AB monotherapy remains less expensive than combination therapy. However, the incremental QALYs gained for combination therapy are twice those of AB monotherapy.
  
  
  CONCLUSIONS
  • The model is sensitive to variability in estimates of health state utility assigned on the basis of symptom severity, indicating that both monotherapy and combination therapy have an advantage in maintaining patients in less severe symptom states. •  Overall, combination therapy for BPH is expected to provide the greatest net monetary benefit at willingness-to-pay thresholds at or above ≈€6000 (£5400).
authors.affiliation: Urology Department, Århus University Hospital, Århus, Denmark.
authors.forename: Truls E
authors.initials: TE
authors.lastname: Bjerklund Johansen
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Baker
authors.forename: Libby K
authors.initials: LK
authors.lastname: Black
mesh_terms: D058891:5-alpha Reductase Inhibitors / Q000008:administration & dosage* / Q000191:economics*; D058668:Adrenergic alpha-1 Receptor Antagonists / Q000008:administration & dosage* / Q000191:economics*; D000368:Aged; D001378:Azasteroids / Q000008:administration & dosage* / Q000191:economics*; D003362:Cost-Benefit Analysis; D004359:Drug Therapy, Combination; D000068538:Dutasteride; D006801:Humans; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D011470:Prostatic Hyperplasia / Q000188:drug therapy* / Q000191:economics*; D013449:Sulfonamides / Q000008:administration & dosage* / Q000191:economics*; D000077409:Tamsulosin
chemical_list: D058891:5-alpha Reductase Inhibitors; D058668:Adrenergic alpha-1 Receptor Antagonists; D001378:Azasteroids; D013449:Sulfonamides; D000077409:Tamsulosin; D000068538:Dutasteride