- Use of adequate contraception. Temozolomide has the potential to cause fetal harm. The effects of ATN 224 on the developing human fetus at the recommended therapeutic dose are unknown, but antiangiogenic agents are known to be teratogenic. For these reasons women of child-bearing potential and men with partners of child-bearing potential must agree to use adequate contraception (hormonal and/or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation through the follow up visit 28 days after the last dose of ATN 224 or temozolomide.