Cost-Effectiveness Analysis of Pertuzumab With Trastuzumab and Chemotherapy Compared to Trastuzumab and Chemotherapy in the Adjuvant Treatment of HER2-Positive Breast Cancer in the United States

ObjectiveThe APHINITY trial assessed the effectiveness and the safety of adding pertuzumab to trastuzumab and chemotherapy (THP) compared to trastuzumab and chemotherapy (TH) in the adjuvant management of human epidermal growth factor 2-positive (HER2+) breast cancer. We performed a study to project the potential cost-effectiveness of THP vs. TH.Study DesignTrial-based cost-utility modeling analysis.MethodsWe performed an economic evaluation from a payer perspective using a Markov model with six health states: invasive disease-free survival, non-metastatic recurrence, remission, first-line metastatic, subsequent line metastatic, and death. We parameterized the model using data from both arms in APHINITY extrapolated to a patient's lifetime horizon. Estimates of health state utilities were based on EQ-5D trial data and the literature, and costs were estimated from government sources and the published literature. The primary outcomes of the model were life-years (LYs), quality-adjusted LYs (QALYs), costs, and incremental cost-effectiveness ratios (ICERs). Uncertainty was addressed via univariate and probabilistic sensitivity analyses.ResultsFor the intention-to-treat population, the model projected improved outcomes (by 0.50 LYs and 0.45 QALYs) and increased costs (by $74 420) for ICERs of $147 774/LY gained and $167 185/QALY gained for PHT vs. HT patients. In the node-positive patient population, the model projected improved outcomes (by 0.86 LYs and 0.76 QALYs) and increased costs (by $66 647) for ICERs of $77 684/LY gained and $87 929/QALY gained. For the hormone-receptor-negative patient population, the model projected health gains, increased costs, and ICERs of $147 022/LY gained and $166 518/QALY gained. The results were sensitive to changes in the model time horizon.ConclusionThe addition of pertuzumab to the available regimens for HER2+ early breast cancer is likely to be cost-effective for patients in the U.S. at high risk of recurrence.