OBJECTIVES To evaluate the financial impact on the INHS following the introduction of cinacalcet for patients with intractable PHPT or in those whom parathyroidectomy (PTX) is contraindicated METHODS The number of patients eligible for cinacalcet was estimated by literature and local demographic information. The BIM simulates the impact of PHPT management in patients with or without cinacalcet. Resources to manage patients not receiving cinacalcet included drugs for treatment of secondary osteoporosis, visits and diagnostics and a second PTX for patients refractory to their first PTX. Resources to manage patients receiving cinacalcet included 60 mg/day cinacalcet and all of the above except the re-surgery. The total cost was calculated by applying the resources used, the INHS tariffs for visits, diagnostics and surgery and the reimbursed price for drugs RESULTS It was estimated that in the first three years following market introduction, just 113, 320 and 490 out of 1400 eligible patients with PHPT would be placed on cinacalcet therapy respectively. The baseline cost of PHPT management resulted in € 794 per patient, per year (€ 256 for drugs, € 314 for re-surgery, € 224 for diagnostics). The introduction of cinacalcet resulted in a cost of €3698 per patient per year with cinacalcet costing € 4380, partially offset by savings due to less other drugs (- € 256), avoiding PTX (- € 314) and less diagnostics (- € 112). The total incremental annual budget increase due to addition of cinacalcet was € 417,864, € 1,183,332 and €1,811,978 in the first three years, respectively CONCLUSIONS Because of the low prevalence of intractable PHPT, the incremental financial BI on the INHS following the introduction of cinacalcet would be very small and partially offset by savings from less health care resource use. Based on these calculations, the INHS granted reimbursement for cinacalcet in this new indication in 2008.