Trilaciclib

Trilaciclib is a transient inhibitor of CDK 4 and 6. Hematopoietic stem and progenitor cells (HSPCs) in the bone marrow give rise to circulating neutrophils, RBCs, and platelets.

• COSELA is indicated to decrease the incidence of chemotherapy-induced myelosuppression in adult patients when administered prior to a platinum/etoposide-containing regimen or topotecan-containing regimen for extensive-stage small cell lung cancer (ES-SCLC). COSELA is a kinase inhibitor indicated to decrease the incidence of chemotherapy-induced myelosuppression in adult patients when administered prior to a platinum/etoposide-containing regimen or topotecan-containing regimen for extensive-stage small cell lung cancer.ICD-10: C34.90

• COSELA is contraindicated in patients with a history of serious hypersensitivity reactions to trilaciclib. Reactions have included anaphylaxis [see Warnings and Precautions ( 5.2 )] .contraindicated

COSELA is for intravenous use only. The recommended dose of COSELA is 240 mg/m 2 as a 30-minute intravenous infusion completed no more than 4 hours prior to the start of chemotherapy on each day chemotherapy is administered. ( 2.1 ) Reduce dose in patients with moderate or severe hepatic impairment. ( 2.2 ) See Full Prescribing Information for instructions on preparation and administration. ( 2.3 ) 2.1 Recommended Dosage The recommended dose of COSELA is 240 mg/m 2 per dose. Administer as a 30-minute intravenous infusion completed no more than 4 hours prior to the start of chemotherapy on each day chemotherapy is administered. The interval between doses of COSELA on sequential days should not be greater than 28 hours. Missed Treatment Session(s) If the COSELA dose is missed, discontinue chemotherapy on the day the COSELA dose was missed. Consider resuming both COSELA and chemotherapy on the next scheduled day for chemotherapy. Discontinuation of Treatment If COSELA is discontinued, wait 96 hours from the last dose of COSELA before resumption of chemotherapy only. 2.2 Dose Modification Dose Modification for Adverse Reactions Withhold, discontinue, or alter the administration of COSELA to manage adverse reactions as described in Table 1 [see Warnings and Precautions ( 5 )].

Injection-Site Reactions, Including Phlebitis and Thrombophlebitis: Monitor for signs and symptoms of injection-site reactions, including phlebitis and thrombophlebitis during infusion. Stop infusion and permanently discontinue COSELA for severe or life-threatening reactions. ( 5.1 ) Acute Drug Hypersensitivity Reactions: Monitor for signs and symptoms of acute drug hypersensitivity reactions, including edema (facial, eye, and tongue), urticaria, pruritus, and anaphylactic reactions. Withhold COSELA for moderate reactions, and permanently discontinue for severe or life-threatening reactions. ( 5.2 ) Interstitial Lung Disease (ILD)/Pneumonitis: Patients treated with CDK4/6 inhibitors should be monitored for pulmonary symptoms indicative of ILD/pneumonitis. Interrupt and evaluate patients with new or worsening symptoms suspected to be due to ILD/pneumonitis. Permanently discontinue COSELA in patients with recurrent symptomatic or severe/life-threatening ILD/pneumonitis. ( 5.3 ) Embryo-Fetal Toxicity: Can cause fetal harm. Advise patients of the potential risk to a fetus and to use effective contraception. ( 5.4 ) 5.1 Injection-Site Reactions, Including Phlebitis and Thrombophlebitis COSELA administration can cause injection-site reactions including phlebitis and thrombophlebitis. Injection-site reactions including phlebitis and thrombophlebitis occurred in 56 (21%) of 272 patients receiving COSELA in clinical trials, including Grade 2 (10%) and Grade 3 (0.4%) adverse reactions (ARs).

The following clinically significant adverse reactions are described elsewhere in the label: Injection-Site Reactions, including phlebitis and thrombophlebitis [ s ee Warnings and Precautions ( 5.1 )] Acute Drug Hypersensitivity Reactions [see Warnings and Precautions ( 5.2 )] ILD/Pneumonitis [see Warnings and Precautions ( 5.3 )] The most common adverse reactions (≥10% of patients with ≥2% difference in incidence compared to placebo) were fatigue, hypocalcemia, hypokalemia, hypophosphatemia, aspartate aminotransferase increased, headache, and pneumonia. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact G1 Therapeutics, Inc., at 1-800-790-4189 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The safety of COSELA was evaluated in Studies 1, 2, and 3 [see Clinical Studies ( 14 )] . Patients received COSELA 240 mg/m 2 by 30-minute intravenous infusion prior to chemotherapy on each chemotherapy day.

Lactation: Advise not to breastfeed. ( 8.2 ) 8.1 Pregnancy Risk Summary Based on the mechanism of action, COSELA can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology ( 12 )] . There are no available human or animal data on COSELA use to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Advise pregnant women of the potential risk to a fetus. The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. However, the background risk of major birth defects is 2% to 4% and of miscarriage is 15% to 20% of clinically recognized pregnancies in the United States general population. 8.2 Lactation Risk Summary There are no data on the presence of trilaciclib in either human or animal milk, the effects on the breastfed child or the effects on milk production. Because of the potential for serious adverse reactions in breastfed children, advise lactating women to not breastfeed while taking COSELA and for at least 3 weeks after the last dose. 8.3 Females and Males of Reproductive Potential Pregnancy Testing Based on its mechanism of action, COSELA can cause fetal harm if administered to a pregnant woman [see Use in Specific Populations ( 8.1 )].

Metabolism

The maximum concentration (C max ) increased proportionally whereas the total plasma exposure (AUC 0-last ) increased slightly greater than proportional over a dosage range of trilaciclib 200 mg/m 2 to 700 mg/m 2 (0.83 to 2.9 times the approved recommended dose). There was no accumulation of trilaciclib following repeated dosing.

• Feb 12, 2021NDANDA214200Pharmacosmos

1. 1Myelosuppression3515%
2. 2Off Label Use2712%
3. 3Dyspnoea187.7%
4. 4White Blood Cell Count Decreased187.7%
5. 5Platelet Count Decreased177.3%
6. 6Death166.8%
7. 7Pneumonia156.4%
8. 8Anaemia146.0%
9. 9Performance Status Decreased146.0%
10. 10Fatigue135.6%
11. 11Infection125.1%
12. 12Haemorrhage114.7%
13. 13Infusion Site Pain114.7%
14. 14Nausea114.7%
15. 15Red Blood Cell Count Decreased114.7%

The 10 most recently updated of 44 ClinicalTrials.gov registrations naming Trilaciclib as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• I-SPY TRIAL: Neoadjuvant and Personalized Adaptive Novel Agents to Treat Breast Cancer
  Recruiting · Phase 2 · Interventional · 5,000 enrolled · QuantumLeap Healthcare Collaborative
  NCT01042379updated 2026-05-06
• Phase II Trial of Trilaciclib, Pembrolizumab, Gemcitabine and Carboplatin in Metastatic Triple-Negative Breast Cancer
  Active not recruiting · Phase 2 · Interventional · 36 enrolled · Wake Forest University Health Sciences
  NCT06027268updated 2026-04-22
• Trilaciclib in Patients Receiving Sacituzumab Tirumotecan for EGFR-mutated, Advanced Non-Small Cell Lung Cancer (NSCLC)
  Recruiting · Phase 2 · Interventional · 49 enrolled · The First Affiliated Hospital of Xiamen University
  NCT06992739updated 2026-04-14
• Study of Trilaciclib and Lurbinectidin
  Recruiting · Phase 2 · Interventional · 30 enrolled · UNC Lineberger Comprehensive Cancer Center
  NCT05578326updated 2026-03-30
• Trilaciclib in Combination With Chemotherapy in Patients With CDK4/6-Dependent Solid Tumors
  Recruiting · Phase 1 · Interventional · 100 enrolled · Hebei Medical University Fourth Hospital
  NCT07490236updated 2026-03-24
• Effect of Trilaciclib in the Prevention of Myelosupression in Subjects With Limited-stage Small Cell Lung Cancer
  Not yet recruiting · Phase 3 · Interventional · 120 enrolled · Pharmacosmos A/S
  NCT07473128updated 2026-03-16
• the Prevention of Bone Marrow Suppression Caused by Chemotherapy in Advanced NSCLC With Trilaciclib
  Enrolling by invitation · Phase 2 · Interventional · 41 enrolled · Henan Cancer Hospital
  NCT06370416updated 2026-01-28
• Bone Marrow Protection, Safety, Efficacy of Trilaciclib and Eribulin in Locally Advanced or Metastatic TNBC(Triple-negative Breast Cancer)
  Not yet recruiting · Phase 2 · Interventional · 29 enrolled · Sun Yat-sen University
  NCT07255612updated 2025-12-01
• Carboplatin, Etoposide, and Atezolizumab With or Without Trilaciclib (G1T28), a CDK4/6 Inhibitor, in Extensive-Stage SCLC
  Completed · Phase 2 · Interventional · 107 enrolled · G1 Therapeutics, Inc.
  NCT03041311updated 2025-09-25
• Trilaciclib (G1T28) in Patients With Previously Treated Extensive Stage SCLC Receiving Topotecan Chemotherapy
  Completed · Phase 1 · Phase 2 · Interventional · 123 enrolled · G1 Therapeutics, Inc.
  NCT02514447updated 2025-09-25

Frequently asked questions

How does Trilaciclib work?

Trilaciclib is a transient inhibitor of CDK 4 and 6. Hematopoietic stem and progenitor cells (HSPCs) in the bone marrow give rise to circulating neutrophils, RBCs, and platelets.

What is Trilaciclib used for?

According to FDA labeling, Trilaciclib carries indications including: COSELA is indicated to decrease the incidence of chemotherapy-induced myelosuppression in adult patients when administered prior to a platinum/etoposide-containing regimen or topotecan-containing regimen for extensive-stage small cell lung cancer (ES-SCLC). COSELA is a kinase inhibitor indicated to decrease the incidence of chemotherapy-induced myelosuppression in adult patients when administered prior to a platinum/etoposide-containing regimen or topotecan-containing regimen for extensive-stage small cell lung cancer.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Trilaciclib?

Trilaciclib is classified as Detoxifying agents for antineoplastic treatment, Kinase Inhibitor, Cyclin-dependent Kinase 4 Inhibitors, Cyclin-dependent Kinase 6 Inhibitors, Kinase Inhibitors, Multidrug and Toxin Extrusion Transporter 1 Inhibitors, Multidrug and Toxin Extrusion Transporter 2 K Inhibitors, Organic Cation Transporter 2 Inhibitors, Cellular Communication Alteration.

What are the brand names for Trilaciclib?

Trilaciclib is marketed under brand names including Cosela.

What are the contraindications for Trilaciclib?

Trilaciclib labeling lists contraindications including: COSELA is contraindicated in patients with a history of serious hypersensitivity reactions to trilaciclib. Reactions have included anaphylaxis [see Warnings and Precautions ( 5.2 )] .. Always consult the full prescribing information and a clinician.