Standard Dosing Schedule for Lurbinectedin
Lurbinectedin ( Zepzelca) is administered intravenously every 21 days as a 30-minute infusion of 3.2 mg/m² in adults with metastatic small cell lung cancer (SCLC) that progressed after platinum-based chemotherapy.[1][2]
How It's Given in Practice
Premedicate with corticosteroids (e.g., dexamethasone 10 mg IV 30 minutes before) to prevent nausea and vomiting. No dose adjustments for mild hepatic impairment; reduce to 2.4 mg/m² (75% of dose) for moderate impairment (total bilirubin >1.5 to ≤3x ULN or AST >3x ULN). Hold or discontinue for severe cases or platelet counts below 100,000/mm³.[1][2]
What Happens If a Dose Is Missed or Delayed
Administer as soon as possible if delayed by less than a week; otherwise, wait until the next scheduled cycle. Do not double doses. Treatment continues until disease progression or unacceptable toxicity.[1]
Dose Adjustments for Side Effects
Reduce dose sequentially to 2.4 mg/m², then 2.0 mg/m² for grade 4 hematologic toxicity, grade 3/4 nonhematologic toxicity, or persistent grade 2/3 effects despite supportive care. Permanently discontinue for grade 4 nonhematologic toxicity not improving to grade 1, or after two dose reductions.[1][2]
Differences from Other SCLC Treatments
Unlike daily oral topotecan or every-3-weeks irinotecan, lurbinectedin's 21-day cycle supports outpatient use with less frequent monitoring. Median progression-free survival was 5.3 months vs. 3.8 months for topotecan investigator's choice in the phase 3 trial.[2]
[1]: FDA Label for Zepzelca (lurbinectedin)
[2]: Drugs.com - Lurbinectedin Dosing