OBJECTIVES: To evaluate long-term cost-effectiveness of a fixed-dose combination (FDC) product comprising 0.5mg dutasteride and 0.4mg tamsulosin daily, compared to concomitant administration of both dutasteride (0.5 mg) and tamsulosin (0.4 mg) monotherapies for the treatment of symptomatic benign prostatic hyperplasia (BPH) in Quebec, Canada.  METHODS: Our previously reported Markov state transition model was adapted to simulate the costs and outcomes associated with patients on either type of combination therapy for a 10-year period. As both combination therapies have been shown to be bioequivalent, a cost-minimization analysis was conducted from the perspective of the Quebec provincial healthcare system. The model follows a Quebec cohort of 312,448 male patients aged ≥50 years, diagnosed with moderate to severe symptomatic BPH, similar to the cohort studied in the pivotal 4-year CombAT study, which evaluated concomitant therapy of dutasteride and tamsulosin in BPH patients at risk of clinical progression.  Costs and outcomes were discounted at 5% per year. Results are presented in the form of total healthcare costs, including dispensing fees, over a period of 10 years for both combination therapies.   RESULTS: Over a 10-year period, the use of FDC compared with concomitant Dutasteride + Tamsulosin therapy could save the Quebec healthcare payer up to $356.86m over 10 years ($1.995bn for FDC vs $2.352bn for concomitant therapy, or $1152/patient) when dispensing fees were included, or $140.4m (or $450/patient) without dispensing fees. This cost-saving is driven by lower wholesale acquisition costs of FDC compared to Dutasteride + Tamsulosin administered concomitantly, and the fact that that only one prescription is needed when dispensing the new FDC (when considering dispensing fees).  CONCLUSIONS: The introduction of the FDC in Quebec for the treatment of moderate to severe symptomatic BPH patients would be expected to yield a cost-savings to the healthcare system over a 10-year period.