- Pregnant women are excluded from this study because Triapine® is a heterocyclic carboxaldehyde thiosemicarbazone with the potential for teratogenic or abortifacient effects; because there is an unknown but potential risk for adverse events in nursing infants secondary to treatment of the mother with Triapine®, breastfeeding should be discontinued if the mother is treated with Triapine®; these potential risks may also apply to other agents used in this study