Abstract P3-12-02: Cost-effectiveness analysis of adding neoadjuvant chemotherapy with pertuzumab, in patients with HER2+ breast cancer in Spain

OBJECTIVES: Given the increase resource constriction of the healthcare systems, efficiency analyses are become more frequent to give additional information to help decision makers in the adoption of new interventions that have already proved clinical value. The use of a neoadjuvant chemotherapy regimen including pertuzumab, trastuzumab and docetaxel (PTD) has demonstrated to improve pathological complete response (pCR) in patients with HER2+ breast cancer (BC). The objective of this study was to estimate the cost-effectiveness of PTD vs. TD in Spain. METHODS: Clinical outcomes from the NeoSphere trial were combined with local data regarding the use of resources associated to patients' follow-up and management of recurrences in a Markov model. Markov models are commonly used to represent the evolution of cancer patients, the effect on clinical outcomes and costs of alternative treatment strategies. In this study, patients with HER2+ BC were modeled through six different health states (event-free, locoregional-relapse, remission, metastatic-relapse [1L], metastatic-relapse [2L], and death) in two cohorts receiving PTD or TD. Long-term effects were estimated by fitting a log-logistic distribution (other techniques were also explored) to event free survival (EFS) data from the NeoSphere study (prevention of 5% relapses at 5 years) combined with utility estimates from the literature. Other transition probabilities as well as unit costs were also obtained from the literature and validated by a 15-oncologists Delphi panel, as well as the estimation of the patients follow-up and recurrences costs. The effectiveness was expressed in terms of quality adjusted life years (QALY) and the analysis was performed from the perspective of the Spanish National Healthcare System (NHS) over a lifetime horizon (a 3% annual discount rate was used for both costs and effects). Deterministic and probabilistic sensitivity analyses (PSA) were performed to assess the robustness of the model results and the influence of different input parameters. RESULTS: PTD was associated to higher effectiveness than PT (14.007 and 13.447 QALY respectively) and lower lifetime costs (€141.070 € and €148.299 € respectively). PTD was also a dominant option over PT when pathological complete response results from the NeoSphere study were combined with EFS data from the CTNeoBC analysis to estimate long-term results. Both the deterministic and probabilistic sensitivity analyses confirmed the robustness of the results, showing that PTD was a dominant option in more than 90% simulations in the PSA. CONCLUSIONS: Beyond the better long-term health outcomes, the combination of PTD would also result in lower lifetime costs for the Spanish NHS, showing that adding pertuzumab is a dominant strategy in HER2+ BC patients receiving neoadjuvant therapy. Citation Format: Abanell J, Ciruelos E, De la Haba J, Martín M, Muñoz-Molina B, De Salas-Cansado M, Colomer R. Cost-effectiveness analysis of adding neoadjuvant chemotherapy with pertuzumab, in patients with HER2+ breast cancer in Spain [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-12-02.