How does lurbinectedin affect pregnancy?

Pregnancy Category and FDA Warnings

Lurbinectedin (brand name Zepzelca) carries a boxed warning for embryo-fetal toxicity. It can cause fetal harm when administered to pregnant women, based on its mechanism as a DNA-damaging agent that impairs cell division.[1] Animal studies show developmental toxicity, including reduced fetal weight, skeletal variations, and increased post-implantation loss at doses below human equivalents.[2]

Effects on Fetus from Studies

In rats and rabbits, lurbinectedin exposure led to:
- Embryofetal death at maternally toxic doses.
- Malformations like cleft palate and limb defects.
- Growth restriction and placental insufficiency.

No human pregnancy data exist due to ethical constraints, but the drug's genotoxic profile suggests high risk of miscarriage, birth defects, or fetal death.[1][2]

Recommendations for Patients

Women of reproductive potential must use effective contraception during treatment and for 6 months after the last dose. Verify pregnancy status before starting therapy. Men with pregnant partners should use condoms during treatment and for 4 months post-treatment.[1] Discontinue breastfeeding during treatment and for 2 weeks after.[2]

What If Exposed During Pregnancy?

Report exposure to the Zepzelca Pregnancy Exposure Registry (1-888-661-7284) or FDA MedWatch. Consult maternal-fetal medicine specialists immediately; options may include termination counseling based on gestational age and risks.[1] No antidote exists; management focuses on monitoring and supportive care.

Sources
[1]: Zepzelca Prescribing Information (FDA)
[2]: Drugs.com - Lurbinectedin Pregnancy