Abstract PS10-16: Real-world efficacy of ribociclib + aromatase inhibitor/fulvestrant, or endocrine monotherapy, or chemotherapy as first-line treatment in women with HR-positive, HER2-negative locally advanced or metastatic breast cancer: Third interim analysis from the RIBANNA study
Authors: Wöckel Achim , Brucker Cosima , Decker Thomas , Falbrede Jörg , Forstbauer Helmut , Göhler Thomas , Hoffmann Oliver , Jackisch Christian , Janssen Jan , Köhler Andreas , Lüdtke-Heckenkamp Kerstin , Lüftner Diana , Marmé Frederik , Nusch Arnd , Reimer Toralf , Roos Christian , Schmidt Marcus , Weide Rudolf , Fasching Peter 
Published: February 2021

Background: In MONALEESA-3 and MONALEESA-7 trials, ribociclib (RIB, a selective CDK4/6 inhibitor) in combination with endocrine therapy (aromatase inhibitor [AI] or fulvestrant [FUL]) demonstrated a significant prolongation of overall survival among patients with breast cancer (BC), regardless of menopausal status and treatment-line. In the premenopausal or perimenopausal women, RIB + AI/FUL should be combined with a luteinizing hormone-releasing hormone agonist. The real-world evidence for the effectiveness, safety, and tolerability of RIB + AI/FUL in the routine clinical practice is needed to support the use of this combination. Methods: RIBANNA is a prospective, non-interventional study ongoing in Germany since October 2017. Pre-, peri- and postmenopausal women (planned, n = 3020) treated with RIB + AI/FUL, or endocrine monotherapy (ET), or chemotherapy (CT) as the first-line treatment for HR+/HER2- aBC in accordance with German guidelines were included. Data from routine clinical practice in all 3 cohorts, including further lines of sequential therapy, were collected. Updated data on baseline demographics and safety analysis will be presented. Additionally, first experience with CANKADO, an innovative digital and patient-friendly application for electrocardiogram (ECG) measurement, are described. By combining this app to Kardia mobile (AliveCor’s single lead device), single-lead ECG can be recorded and sent via the CANKADO app for a cardiologist to read over. The cardiologist reviews the measurements, and reports the corrected QT interval by Fredericia (QTcF) results towards the trial site. Impact of the use of CANKADO onto the clinical routine will be analyzed. Results: For the second interim analysis, 1141 patients were enrolled until July 12th, 2019, while the full analysis set comprised 813 patients (Table 1). Median duration of RIB exposure in patients on RIB + AI/FUL vs total population was 151 vs 150 days respectively. At cut-off date, patients received first-line (89%, n = 1016), second-line (7%, n = 82), and third-line treatments (1%, n = 11). A starting dose of 600 mg per day for RIB in the first-line setting was seen in most of the patients (85%); data of second-line patients will be reported later. The first-line mean daily dose of RIB was 451.6 mg/day RIB was prescribed mainly in combination with letrozole (75%), fulvestrant (12%), anastrozole (7%), and exemestane (6%). A total of 62% of patients in the study were documented as therapy-naïve for ET. Of 424 patients with early breast cancer, 129 (30%) had documented prior CT without ET. The most common all-grade adverse events frequently noted in RIB + AI/FUL cohort in comparison with other cohorts were nausea (RIB [19%] vs ET [9%] vs CT [11%]), neutropenia (19% vs 1% vs 10%), fatigue (17% vs 9% vs 14%), and leukopenia (14% vs 4% vs 12%). The usage of CANKADO application to assess QTcF was initiated in the year 2019 and first data will be presented. Conclusion: RIBANNA study showed diverse population characteristics among the patients who received RIB treatment in a real-world setting. The third interim analysis is planned in October 2020, and the updated baseline data, information on safety, digital ECG measurement using CANKADO application will be presented.

Baseline Demographic Characteristics as of Second Interim AnalysisDemographic VariableRIB + AI/FUL (n = 658)Endocrine Therapy (n = 78)Chemotherapy (n = 77)Mean age, years (SD)67 (11)72 (12)62 (10)Mean time since initial diagnosis, years6.17.23.6T stage at baseline*, n (%)TX204 (31)28 (36)18 (23)T0+T1132 (20)12 (15)11 (14)T2-T4302 (46)35 (45)42 (54)N stage at baseline*, n (%)NX212 (32)29 (37)28 (36)N0+N1317 (48)36 (46)35 (46)N2+N3108 (16)10 (13)8 (10)M stage at baseline*, n (%)MX6 (1)0 (0)0 (0)M018 (3)1 (1)1 (1)M1616 (94)75 (96)71 (92)Metastatic location at baseline*, n (%)CNS, liver, lungs258 (39)14 (18)42 (54)Bone only181 (28)42 (54)11 (14)Skin, lymph nodes, other149 (23)16 (20)14 (18)*Remaining cases are missing.CNS, central nervous system.

Citation Format: Achim Wöckel, Cosima Brucker, Thomas Decker, Jörg Falbrede, Helmut Forstbauer, Thomas Göhler, Oliver Hoffmann, Christian Jackisch, Jan Janssen, Andreas Köhler, Kerstin Lüdtke-Heckenkamp, Diana Lüftner, Frederik Marmé, Arnd Nusch, Toralf Reimer, Christian Roos, Marcus Schmidt, Rudolf Weide, Peter Fasching. Real-world efficacy of ribociclib + aromatase inhibitor/fulvestrant, or endocrine monotherapy, or chemotherapy as first-line treatment in women with HR-positive, HER2-negative locally advanced or metastatic breast cancer: Third interim analysis from the RIBANNA study [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 PS10-16.