Cost effectiveness of tibial nonunion treatment: A comparison between rhBMP-7 and autologous bone graft in two Italian centres

Abstract

Current evidences show that recombinant human bone morphogenetic protein 7 (rhBMP-7, eptotermin alfa) can be considered an effective alternative to autologous bone graft (ABG) in the treatment of tibial nonunions. Few studies, so far, have analysed the costs of treating tibial nonunions with either rhBMP-7 or ABG and none of them has specifically considered the Italian situation. The aim of the present study was to capture, through observational retrospective methods, the direct medical costs associated with the treatment of tibial nonunions with rhBMP-7 or ABG in Italy and to compare the cost effectiveness of the two interventions. The secondary objective was to perform a cost-reimbursement analysis for hospitalisations associated with the two treatments. Data of 54 patients with indication for tibial nonunion were collected from existing data sources. Of these patients, 26 were treated with ABG and 28 with rhBMP-7. The study captured the direct medical costs for treating each tibial nonunion, considering both inpatient and outpatient care. The hospital reimbursement was calculated from discharge registries, based on diagnosis-related group (DRG) values. A subgroup of patients (n=30) was also interviewed to capture perceived health during the follow-up, and the quality-adjusted life years (QALYs) were subsequently computed. The two groups were similar for what concerns baseline characteristics. While the medical costs incurred during the hospitalisation associated with treatment were on average €3091.21 higher (P<0.001) in patients treated with rhBMP-7 (reflecting the product procurement costs), the costs incurred during the follow-up were on average €2344.45 higher (P=0.02) in patients treated with ABG. Considering all costs incurred from the treatment, there was a borderline statistical evidence (P=0.04) for a mean increase of €795.42, in the rhBMP-7 group. Furthermore, the study demonstrated that, without appropriate reimbursement, the hospital undergoes significant losses (P=0.003) when using rhBMP-7 instead of ABG. In contrast to these losses, in Italy, the average cost to achieve a successful outcome was €488.96 lower in patients treated with rhBMP-7 and, additionally, the cost per QALY gained was below the cost-utility threshold of $50,000.

Keywords: Adverse events; Cost effectiveness; Cost utility; Costs; Eptotermin alfa; Italy; OP-1; Osteogenic protein 1; Tibial nonunions; rhBMP-7.