Cost Effectiveness of Paricalcitol versus a non-selective vitamin D receptor activator for secondary hyperparathyroidism in the UK: a chronic kidney disease markov model

Abstract

Background: secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD) and a frequent cause of clinically significant bone disease. Non-selective vitamin D receptor (VDR) activator treatment has been used to treat the condition but is ineffective for many patients with hypercalcaemia and hyperphosphataemia and may precipitate worsening of their condition. Compared with non-selective VDR activator treatment, use of the VDR ligand paricalcitol may increase survival and reduce the risk of morbidities in patients with SHPT, which may have health economic consequences.

Objective: the objective of this study was to determine the cost effectiveness of paricalcitol versus a non-selective VDR activator for the treatment of SHPT in patients with CKD in the UK setting.

Methods: A Markov process model was developed employing data sources from the published literature, paricalcitol clinical trials and observational studies, official UK price/tariff lists and national population statistics. The comparator was alfacalcidol, a non-selective VDR activator medication. The primary perspective of the study was that of the UK National Health Service (NHS). The efficacy outcomes (reductions in SHPT, proteinuria, complications and mortality) were extrapolated to: number of life-years gained (LYG) and number of quality-adjusted life-years (QALYs). Clinical and economic outcomes were discounted at 3.5%. The year of costing for costs determined in the study was 2006.

Results: the reference case analysis was a 10-year time horizon, based on a comparison of paricalcitol with a non-selective VDR activator, which is started in CKD stage 3 (moderate reduction in glomerular filtration rate [GFR] with kidney damage) and continued in CKD stage 4 (severe reduction in GFR) and CKD stage 5 (established kidney failure). The use of paricalcitol leads to an additional medical cost of pound3224 ($US5970). The health benefits of paricalcitol lead to an increase in LYG of 0.52 and a gain in QALYs of 0.465. Therefore the use of paricalcitol results in an incremental cost-effectiveness ratio of pound6933/QALY ($US12 840/QALY) from the primary perspective of the NHS. One-way sensitivity analyses and probabilistic sensitivity analyses confirmed the robustness of the model.

Conclusion: this model showed that the favourable clinical benefit of paricalcitol results in positive short- and long-term health economic benefits. This study suggests that the use of paricalcitol in patients with early CKD may be cost effective from the UK NHS perspective versus non-selective VDR activator medication.