Modelling the cost-effectiveness of adjuvant lapatinib for early-stage breast cancer

Abstract

Background. It has been shown in the NeoALTTO trial that a neoadjuvant regimen containing paclitaxel, lapatinib and trastuzumab is superior to regimens which include only one of the HER2 antagonists with paclitaxel. In light of these results, we modelled the potential cost-effectiveness of adjuvant lapatinib for patients with HER2-positive early-stage breast cancer. Material and methods. We constructed a Markov state-transition model with three different health states: disease free, relapse, and death. We assumed an 18-week course of lapatinib was added to the TCH arm of the BCIRG 006 trial. Since no efficacy data are available for combining adjuvant lapatinib with trastuzumab, we ran the model assuming five different hypothetical hazard ratios for disease free survival when lapatinib is added to TCH (TCH was used as the control group). The hazard ratios were 0.9, 0.8, 0.7, 0.6, and 0.5. Outcomes are given in quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at the 4% rate. We calculated the cost per QALY from the perspective of the Irish health care system. Probabilistic sensitivity analysis and one-way sensitivity were performed and confidence