Abstract PD12-11: Patient-reported outcomes from the Phase III IMpassion031 trial of neoadjuvant atezolizumab + chemotherapy in early triple-negative breast cancer

Abstract Background: In the IMpassion031 study (NCT03197935) of patients (N = 333) with invasive stage II or III early triple-negative breast cancer (eTNBC), neoadjuvant treatment with atezolizumab vs placebo, each combined with nab-paclitaxel followed by doxorubicin + cyclophosphamide, significantly improved pathologic complete response in the intent-to-treat population. Patient-reported outcomes (PROs) were collected to document patient perspectives on overall treatment burden and clinical benefit of atezolizumab + chemotherapy for neoadjuvant treatment of eTNBC. Methods: Patients received either atezolizumab 840 mg or placebo every 2 weeks (q2w) with nab-paclitaxel 125 mg/m2 every week for 12 weeks followed by atezolizumab 840 mg or placebo q2w with doxorubicin 60 mg/m2 + cyclophosphamide 600 mg/m2 q2w for 4 cycles. After surgery, patients in the atezolizumab arm were unblinded and continued to receive atezolizumab 1200 mg every 3 weeks for 11 doses, while patients in the control arm did not receive any study treatment. Patients completed the EORTC Quality of Life Questionnaire Core 30 (QLQ-C30) and single-item GP5 from the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire at baseline and day 1 of each cycle of neoadjuvant and adjuvant treatment, at end of treatment and during follow-up every 3 months during year 1, every 6 months during years 2-3, and then annually. Mean and mean change from baseline scores (with changes ≥ 10 considered clinically meaningful) in function (role and physical) and global health status/health-related quality of life (GHS/HRQoL) were predefined secondary endpoints. Mean and mean change from baseline scores in disease and treatment-related symptoms, as well as an assessment of overall side-effect bother, were exploratory endpoints. Expected results: The PROs will be compared between the atezolizumab and placebo arms to assess overall treatment burden and the effect of adding atezolizumab to neoadjuvant chemotherapy for the treatment of eTNBC. Citation Format: Elizabeth Mittendorf, Nadia Harbeck, Hong (Amy) Zhang, Shigehira Saji, Kyung Hae Jung, Sheetal Patel, Shilpen Patel, Anh Nguyen Duc, Mario Liste-Hermoso, Stephen Y Chui, Carlos H Barrios. Patient-reported outcomes from the Phase III IMpassion031 trial of neoadjuvant atezolizumab + chemotherapy in early triple-negative breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD12-11.