What are we paying for? A cost-effectiveness analysis of patented denosumab and generic alendronate for postmenopausal osteoporotic women in Australia

Abstract

ObjectiveZoledronic acid and denosumab were funded by the Australian government for the management of osteoporosis at an equivalent price to alendronate. The price of alendronate has declined by around 65 %, but the price of the other two therapies has remained stable. Using data published since the listing, this paper reports current estimates of the value of denosumab compared to alendronate from an Australian health system perspective.MethodsA cohort-based state transition model was developed that predicted changes in bone mineral density (BMD), and calibrated fracture probabilities as a function of BMD, age and previous fracture to estimate differences in costs and QALYs gained over a 10-year time horizon.ResultsThe base-case incremental cost per QALY gained for denosumab versus alendronate was $246,749. There is a near zero probability that denosumab is cost-effective at a threshold value of $100,000 per QALY gained. If the price of denosumab was reduced by 50 %, the incremental cost per QALY gained falls to $50,068.DiscussionCurrent Australian legislation precludes price reviews when comparator therapies come off patent. The presented analysis illustrates a review process, incorporating clinical data collected since the original submission to inform a price at which denosumab would provide value for money.

An Updated Systematic Review of Cost-Effectiveness Analyses of Drugs for Osteoporosis

“…However, we found that some studies including both direct and indirect costs were not defined as having a societal perspective, although this was the original information stated by authors reported in Table 1; no adjustment and correction were made for this. Nineteen studies applied a lifetime horizon while others considered truncated time horizons [10][11][12][13][14][15]. A Markov model was used in 21 studies, consisting of a Markov cohort model (n = 12) or a Markov microsimulation model (n = 9).…”

Cost-Effectiveness of Pharmacological Treatments for Osteoporosis Consistent with the Revised Economic Evaluation Guidelines for Canada

“…50,51 Five manufacturer-sponsored studies were identified and two independent studies—one comparing denosumab and alendronate and another comparing anabolic drugs (abaloparatide and teriparatide) to no therapy. 41,45–48,52,53…”

Denosumab: A Unique Perspective on Adherence and Cost-effectiveness Compared With Oral Bisphosphonates in Osteoporosis Patients

“…31,34 Up to 60% of studies examined a long time horizon of a lifetime (n = 9), whereas 2 studies utilized a 5-year horizon 32,35 and 4 studies assessed the impact over a 10-year time horizon. 31,34,36,37 Among 11 articles that reported discounting in the methods, the majority (55%) discounted both cost and outcomes by 3%, whereas other studies utilized discounts of 1.5%, 41 3.5%, 34 and 5%. 32,36,38 The annual cost (2017 US dollars) of denosumab ranged from $420.81 in Australia 36 to $1761.62 in the United States, 14 which was always higher than the cost of generic alendronate, which ranged from $25.11 in Sweden 33 to $400.44 in Canada.…”

“…31,34,36,37 Among 11 articles that reported discounting in the methods, the majority (55%) discounted both cost and outcomes by 3%, whereas other studies utilized discounts of 1.5%, 41 3.5%, 34 and 5%. 32,36,38 The annual cost (2017 US dollars) of denosumab ranged from $420.81 in Australia 36 to $1761.62 in the United States, 14 which was always higher than the cost of generic alendronate, which ranged from $25.11 in Sweden 33 to $400.44 in Canada. 38 Only 2 studies reported having no conflicts of interest, 39,42 whereas 7 studies included industry authors.…”