Purpose: Trilaciclib is an intravenous cyclin-dependent kinase 4/6 inhibitor indicated to decrease the incidence of chemotherapy-induced myelosuppression (CIM) by protecting hematopoietic stem and ...progenitor cells and immune system function from chemotherapy-induced damage (myeloprotection). Here, we investigated the myeloprotective effects of trilaciclib among patients at increased risk of CIM. Patients and Methods: Data were pooled from three randomized, double-blind, placebo-controlled, phase 2 clinical studies of trilaciclib administered prior to chemotherapy in patients with extensive-stage small cell lung cancer (ES-SCLC). Myeloprotective outcomes were evaluated in patient subgroups based on age (<65 or greater than or equal to65 years), risk of chemotherapy-induced febrile neutropenia (FN), and risk of anemia or red blood cell (RBC) transfusions. For the FN and anemia analyses, risk factors were identified from published literature and used to classify patients into FN and anemia risk categories. Subgroup analysis based on age was also performed on patient reported outcome (PRO) measures. Results: In total, 123 patients received trilaciclib and 119 patients received placebo. Myeloprotective benefits of trilaciclib were observed regardless of age, with greater effects observed among patients aged greater than or equal to65 years. Across FN risk factors and categories, trilaciclib had beneficial effects on neutrophil-related endpoints vs placebo, with greater effects observed in patients at higher risk of FN. Effects on RBC-related endpoints favored trilaciclib vs placebo, regardless of anemia risk factors and categories. Improvements in PROs with trilaciclib were observed irrespective of age group, but with greater improvements and less deterioration from baseline observed in older patients. Conclusion: By both decreasing the incidence of CIM and improving quality of life, trilaciclib has the potential to allow patients receiving chemotherapy for ES-SCLC, including patients who are older or more vulnerable to CIM, to receive chemotherapy on schedule and at standard-of-care doses, and to improve the experience for patients receiving chemotherapy to treat ES-SCLC. Clinical Trial Numbers: NCT02499770; NCT03041311; NCT02514447. Keywords: trilaciclib, myelosuppression, myeloprotection, myelopreservation, chemotherapy, small cell lung cancer
Abstract Background: Early stage triple negative breast cancer (TNBC) is associated with a high risk of distant relapse. ALEXANDRA/IMpassion030 is a global, prospective, randomized, open-label, phase ...3 trial that investigated the efficacy, safety and pharmacokinetic profile of adjuvant atezolizumab plus standard anthracycline/taxane chemotherapy (arm A) versus chemotherapy alone (arm B) in early-stage TNBC. Methods: ALEXANDRA/IMpassion030 (NCT03498716) aimed to randomize (1:1) 2300 patients with operable stage II-III TNBC, confirmed by central pathology review. Patients were stratified by type of surgery (breast conserving versus mastectomy), nodal status (0 versus 1-3 versus >=4 nodes), and centrally assessed PD-L1 status (IC 0 vs >=1% ). Adjuvant chemotherapy consisted 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 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 (Arm A) or the same chemotherapy regimen (T-EC/AC) alone (Arm B). The primary endpoint was invasive disease-free survival (iDFS); secondary endpoints included, iDFS in the PD-L1 positive and lymph node-positive subpopulations, overall survival, safety, patient functioning and health related quality of life (HRQoL). On the 14th of November 2022, following an IDMC recommendation, the study accrual was temporarily stopped. In February 2023, the protocol was amended in order for the IDMC to perform an early interim analysis of efficacy and futility, at approximately 62% of the planned (390) iDFS events. The futility boundary was set to a Hazard Ratio (HR) > 1. Results: The IDMC recommendations of 15th March 2023 reported that the primary endpoint crossed the futility boundary, accrual to the study was permanently stopped and the experimental treatment was discontinued. Between August 2018 and November 2022, the study enrolled 2199 patients, with 1101 randomised to the atezolizumab arm (A) and 1098 to the control arm (B). At a median follow-up of 25.3 months, 239 (10.9%) iDFS events were observed in the 2199 enrolled patients; 127 versus 112 iDFS events were observed (61.3% of 390) in the A versus B arms respectively, HR 1.12, (95% confidence interval, CI, 0.87, 1.45). In the PD-L1 positive subgroup, (1567/2199 patients, 71.3%), 77 versus 73 iDFS events were observed in the A versus B arms respectively, HR 1.03, (95% CI 0.75, 1.42). Among patients with lymph node positive tumors (1066/2199 patients, 48.5%), 86 versus 66 iDFS events were observed in the A versus B arm respectively, HR 1.41, (95% CI 1.02, 1.96). Incidence of adverse events grade >=3 was 58.01% versus 48.15% in the A versus B arms, including death in 1.01% (11) and 0.55% (6) of patients, respectively. Conclusions: Crossing the pre-specified futility boundary of HR > 1 provides evidence that adjuvant atezolizumab is very unlikely to improve invasive disease-free survival when added to adjuvant anthracycline and taxane based chemotherapy in patients with stage II-III triple-negative breast cancer. With longer treatment exposure in the atezolizumab arm (A), adverse events were more frequent but consistent with the atezolizumab safety profile. No new or unexpected safety issue was identified. Citation Format: Michail Ignatiadis, Andrew Bailey, Heather McArthur, Sarra El-Abed, Evandro de Azambuja, Otto Metzger, Steve Chui, Max Dieterich, Thomas Perretti, Guenther Steger, Jacek Jassem, Soo Chin Lee, Michaela Higgins, José Zarbá, Marcus Schmidt, Henry Gomez, Angel Guerrero-Zotano, Luca Moscetti, Joanne Win Yang Chiu, Carter DuFrane, Vanessa Honvault, Rosa Altarcheh, Luciana Molinero, Andrew Ellingson, Elisabetta Munzone, Noa Efrat Ben-Baruch, Emilio Bajetta, Shinji Ohno, Seock-Ah Im, Gustavo Werutsky, Einav Gal-Yam, Xavier Gonzalez-Farré, Ling-Ming Tseng, William Jacot, Oleg Gluz, Zhimin Shao, Yaroslav Shparyk, Ivan Sinielnikov, Zimina Anastasia, Aleksandr Vasiliev, Esther Shearer-Kang, Eric Winer, Diogo Martins-Branco, Shona Fielding, David Cameron, Giuseppe Viale, Shigehira Saji, Richard Gelber, Martine Piccart. Adding atezolizumab to adjuvant chemotherapy for stage II and III triple-negative breast cancer is unlikely to improve efficacy: interim analysis of the ALEXANDRA/IMpassion030 phase 3 trial abstract. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr GS01-03.