Abstract 3361: A prescription for new trial designs for drug development focused on the neoadjuvant setting: Save lives, resources, and time

Abstract

Abstract Background: Traditionally, new drug combinations are first tested for safety and efficacy in the stage 4 setting. The I-SPY 2 TRIAL has focused on bringing promising new combinations into the phase 2/3 high-risk setting once safety is established. I-SPY 2 is an adaptive neoadjuvant platform trial for women with stage 2/3 breast cancer at high risk for early recurrence. In this setting, complete pathologic response (pCR) is the primary endpoint. We and others have demonstrated that pCR is highly predictive of distant recurrence free survival at 3 years. In I-SPY 2 the hazard rate is 0.2 (Confidence Interval 0.11-0.37), regardless of subtypes or agent. Agents that extend progression free survival in the metastatic setting, can be lifesaving when given at an earlier stage setting. Methods: The health economic benefits of achieving pCR were investigated using a Markov model describing the risk of recurrence, progression and death. The risk of recurrence was informed by I-SPY 2 and the risk of cancer progression and the associated treatment costs were based on literature values. We assumed constant recurrence rate without accounting for subtype specific rates in this first version of the model. Results: For each additional patient with pathologic complete response a net monetary benefit of $170,000 (Credible Interval 95% 100,000—250,000) and a gain of 4 life-years (CrI 95% 2—6) was predicted. The ICER for pCR is -$45,000. This represents the aggregate benefit across all I-SPY cancers. Modeling accounting for cancer subtype is in process and will be presented also. Conclusion: A short term endpoint, response to chemotherapy in the neoadjuvant setting, which is highly correlated with long term outcome, provides the opportunity to focus drug development on improving that endpoint. Enabling more patients to achieve a pCR would provide enormous benefit in terms of lives and resources saved. The economic modeling, along with the findings from I-SPY 2 suggests that we should shift drug development to the high risk early setting and evolve drug designs to improve every patient’s outcome. In I-SPY 2, we are shifting our platform trial design to increase every patient’s chance to achieve pCR. Platform adaptive trials in the early stage neoadjuvant setting are ideal for advancing the field and maximizing benefit for patients. Citation Format: Andreas Karlsson, Yiwey Shieh, Andre Dempsey, Christina Yau, Angela Dmichele, Doug Yes, Laura van't Veer, Nola Hylton, Martin Eklund, Laura Esserman. A prescription for new trial designs for drug development focused on the neoadjuvant setting: Save lives, resources, and time [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3361.