Abstract
BACKGROUND: Capivasertib has gained US Food and Drug Administration approval in combination with a hormonal-based regimen (eg, fulvestrant) for managing hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer, with results from the CapiTello-291 trial showing Capivasertib plus fulvestrant to have superior efficacy compared with fulvestrant alone. OBJECTIVE: To examine the cost-effectiveness of capivasertib plus fulvestrant vs fulvestrant alone for treating HR+/HER2- advanced breast cancer in the United States from a payer's perspective. METHODS: A Markov model of 708 participants with 3 health states (progression-free, progressive disease, death) from CapiTello-291 trial data was used to compare the costs and efficacy of the two treatment strategies on TreeAge Pro software. This model adopted a willingness-to-pay (WTP) threshold of $100,000 per quality-adjusted life-year (QALY) from a US health care perspective. A 10-year lifetime horizon with a monthly cycle length was used with a 3% discount on costs and utilities derived from previously published resources. To assess our model's uncertainty, multiple one-way sensitivity analyses and probabilistic sensitivity analyses using various distribution ranges of our model parameters were conducted. RESULTS: In the base model, capivasertib plus fulvestrant treatment was expected to generate an incremental 0.62 QALYs at an incremental cost of $79,117.66, which resulted in an incremental cost-effectiveness ratios of $128,283.61/QALY. Our sensitivity analysis shows that at willingness-to-pay levels of $130,000/QALY and $500,100/QALY, the likelihood of capivasertib plus fulvestrant being cost-effective compared with fulvestrant monotherapy was 50% and 100%, respectively. CONCLUSIONS: The findings from this study suggest that adding capivasertib to fulvestrant treatment is not cost-effective when compared with fulvestrant alone, from the perspective of the US health care system. Considering the notable therapeutic impact that the inclusion of this medication in standard treatment plans can have, it is necessary to engage in more extensive talks and negotiations over the pricing of this newly approved medication.