Does lurbinectedin increase birth defect risk?
Yes, lurbinectedin carries a high risk of causing birth defects and fetal harm. It is classified as Pregnancy Category D by the FDA, meaning animal studies show clear evidence of fetal risk, and human data—though limited—suggest potential harm. The drug's label warns against use during pregnancy, as it can cause embryofetal toxicity, including malformations.[1][2]
Evidence from animal studies
In rats and rabbits, lurbinectedin at doses below human equivalents caused reduced fetal weight, skeletal abnormalities, and increased fetal loss. These effects occurred at exposures 0.1-0.4 times the human dose, confirming teratogenic potential.[1]
Human pregnancy data
No controlled trials exist in pregnant women due to ethical concerns. Postmarketing reports and the manufacturer's pharmacovigilance note risks, with recommendations for contraception during treatment and for 6 months after (men and women). Pregnancies during treatment should be terminated if feasible.[1][2]
Recommendations for patients
Women of childbearing potential must verify non-pregnancy via serum pregnancy test before starting. Effective contraception is required. Men should use condoms. Breastfeeding is not advised during treatment and for 2 weeks after.[1]
Related chemotherapy risks
Lurbinectedin, a DNA-binding agent like other alkylators (e.g., cyclophosphamide), shares class-wide teratogenicity. Similar drugs increase congenital anomalies by 10-20% in exposed first-trimester pregnancies.[3]
What if exposure happens accidentally?
Report to the Zepzelca Pregnancy Registry (1-888-438-4231) or FDA MedWatch. Immediate counseling with a teratogen specialist is advised; risks peak in the first trimester.[1]
Sources:
[1] Zepzelca (lurbinectedin) prescribing information, Jazz Pharmaceuticals, 2023. https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/213069s000lbl.pdf
[2] DrugPatentWatch.com entry for lurbinectedin. https://www.drugpatentwatch.com/p/tradename/ZEPZELCA
[3] Briggs' Drugs in Pregnancy and Lactation, 12th ed., 2022.