Cancer Management and Research (Aug 2021)
Myeloprotective Effects of Trilaciclib Among Patients with Small Cell Lung Cancer at Increased Risk of Chemotherapy-Induced Myelosuppression: Pooled Results from Three Phase 2, Randomized, Double-Blind, Placebo-Controlled Studies
Abstract
Maen Hussein,1 Marina Maglakelidze,2 Donald A Richards,3 Marielle Sabatini,4 Todd A Gersten,5 Keith Lerro,6 Ivan Sinielnikov,7 Alexander Spira,8,9 Yili Pritchett,10 Joyce M Antal,10 Rajesh Malik,10 J Thaddeus Beck11 1Florida Cancer Specialists, Leesburg, FL, USA; 2LLC Arensia Exploratory Medicine, Tbilisi, Georgia; 3Texas Oncology-Tyler, US Oncology Research, Tyler, TX, USA; 4Saint Leon Hospital, Bayonne, France; 5Florida Cancer Specialists, West Palm Beach, FL, USA; 6Regional Medical Oncology Center, Wilson, NC, USA; 7Volyn Regional Oncology Center, Lutsk, Ukraine; 8Virginia Cancer Specialists, Fairfax, VA, USA; 9US Oncology Research, The Woodlands, TX, USA; 10G1 Therapeutics, Inc., Research Triangle Park, NC, USA; 11Highlands Oncology Group, Fayetteville, AR, USACorrespondence: Maen HusseinFlorida Cancer Specialists, Leesburg, FL, USATel +1 352-787-9448Email [email protected]: 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 ≥ 65 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 ≥ 65 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