Abstract OT3-05-02: ALEXANDRA/IMpassion030: A phase III study of standard adjuvant chemotherapy with or without atezolizumab in early triple negative breast cancer

Background: Triple negative breast cancer (TNBC) is a subtype with a high risk of relapse in the early disease setting. Because TNBC does not currently have specific targeted agents approved for use in the early setting it is treated primarily with chemotherapy. A growing body of evidence indicates that TNBC is more immunogenic than other subtypes of breast cancer and promising clinical activity has been reported with atezolizumab (an anti–PD-L1 antibody) in Phase 1/1b metastatic TNBC trials. Furthermore, the anti-tumor activity of PD-1/PD-L1 targeting drugs is hypothesized to be enhanced when co-administered with chemotherapy. ALEXANDRA/IMpassion030 will evaluate the efficacy and safety of atezolizumab in combination with standard adjuvant chemotherapy in early TNBC. Methods: ALEXANDRA/IMpassion030 is a global, prospective, randomised, open-label Phase 3 trial investigating the efficacy, safety and pharmacokinetic (PK) profile of adjuvant atezolizumab plus standard chemotherapy versus chemotherapy alone in early TNBC. In total, 2300 patients diagnosed with non-metastatic operable stage II or III TNBC confirmed by central pathology review will be randomised. TumorPD-L1evaluationwill be performed centrally. Patients will be stratified by type of surgery, nodal status, and PD-L1 status. The adjuvant treatment will consist of weekly paclitaxel 80 mg/m2 for 12 weeks followed by dose dense anthracycline (epirubicin 90 mg/m2 or doxorubicin 60 mg/m2) and cyclophosphamide 600 mg/m2 for 4 doses every 2 weeks or the same chemotherapy regimen (T-EC/AC) given concomitantly with atezolizumab 840 mg every 2 weeks followed by maintenance atezolizumab 1200 mg every 3 weeks until completion of 1 year of atezolizumab. Primary end-point is invasive disease-free survival (iDFS) and secondary end-points include iDFS by PD-L1 and lymph node status, overall survival, safety, patient functioning and health related quality of life (HRQoL). Tumour tissue and blood samples will be collected for biomarker research. The first site was activated in May 4th, and approximately 430 sites are expected to be open globally in 30 countries. This trial is sponsored by Roche and conducted in partnership with the Breast International Group, Frontier Science and Technology Research Foundation, Institute Jules Bordet and Alliance Foundation Trials. Clinicaltrials.gov NCT03498716. Citation Format: Ignatiadis M, McArthur H, Bailey A, Martinez J-L, De Azambuja E, Metzger O, Lai C, Ponde N, Goulioti T, Daly F, Bouhlel A, Balta V, Van Dooren V, Viale G, Maetens M, Dufrane C, Nguyen Duc A, Winer E, Gelber R, Piccart M. ALEXANDRA/IMpassion030: A phase III study of standard adjuvant chemotherapy with or without atezolizumab in early triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-05-02.