On February 12, 2021, the FDA approved trilaciclib (Cosela; G1 Therapeutics), as a first-in-class cyclin-dependent kinase (CDK)4/6 inhibitor to reduce the frequency of chemotherapy-induced myelosuppression in adults with extensive-stage small-cell lung cancer, when used before a platinum plus etoposide regimen or a topotecan-containing regimen. Trilaciclib may prevent damage to bone marrow cells by inhibiting the CDK4/6 enzyme. The FDA granted trilaciclib priority review and a breakthrough therapy designation.
“For patients with extensive-stage small-cell lung cancer, protecting bone marrow function may help make their chemotherapy safer and allow them to complete their course of treatment on time and according to plan,” said Albert Deisseroth, MD, PhD, Supervisory Medical Officer at the FDA’s Center for Drug Evaluation and Research. “Today’s approval of Cosela will give patients a treatment option that can reduce the occurrence of a common, harmful side effect of chemotherapy.”
The FDA approved trilaciclib based on data from 3 randomized, double-blind, placebo-controlled studies with a total of 245 patients who were randomized to intravenous trilaciclib or to placebo before chemotherapy. The study compared the incidence rate and duration of severe neutropenia in the first cycle of chemotherapy.
In all 3 studies, patients who received trilaciclib had a lower risk for severe neutropenia than those who received placebo, as well as a shorter duration of severe neutropenia.
The most common (≥10%) adverse events were fatigue, increased levels of aspartate aminotransferase, headache, pneumonia, and deficiencies in calcium, potassium, and phosphate. The grade 3 or 4 hematologic adverse reactions to trilaciclib included neutropenia (32%), thrombocytopenia (18%), anemia (16%), leukopenia (4%), and febrile neutropenia (3%). Trilaciclib therapy is associated with the risk for acute drug hypersensitivity, interstitial lung disease, and pneumonitis.