Myfortic, a drug used to prevent organ rejection in transplant patients, has been linked to drug side effects that include an increased risk of birth defects and miscarriage. Because of this, the Food & Drug Administration (FDA) has added a new boxed warning to the Myfortic label, and Novartis Pharmaceuticals, the drug’s maker, has sent a letter to physicians informing them of the Myfortic birth defect and miscarriage risk and labeling changes.
Myfortic is used in preventing organ rejection following kidney, liver, or heart transplants, and is generally used in combination with cyclosporine and corticosteroids. According to the FDA, postmarketing data collected by the US National Transplantation Pregnancy Registry, as well as other postmarketing data, indicated that Myfortic puts pregnant women at a high risk of miscarriage, and that it is more likely that babies born to women taking Myfortic will suffer from birth defects.
While it was known previously that Myfortic could cause problems during pregnancy, the FDA had classified the risk as Category C (Risk of Fetal Harm Cannot be Ruled Out). These side effects are now classified as Category D (Positive Evidence of Fetal Risk). The FDA has also updated the Myfortic label to include a warning that “Increased risk of first trimester pregnancy loss and increased risk of congenital malformations, especially external ear and facial abnormalities including cleft lip and palate, and anomalies of the distal limbs, heart, esophagus, and kidney” could occur in pregnant women treated with Myfortic.
The FDA has also warned healthcare providers that female patients planning a pregnancy should not be prescribed Myfortic unless other immunosuppressant drugs have been tried and prove ineffective. The FDA also said that female patients of childbearing age must a be given contraceptive counseling, and use two method of birth control while taking Myfortic. They should also be made aware that the Myfortic can interfere with the effectiveness of oral contraceptives. The FDA is also now requiring women of childbearing age to undergo pregnancy testing within one week of beginning Myfortic therapy. A female patient prescribed Myfortic should begin using contraceptives four weeks prior to starting the drug, and for six weeks after stopping.
Finally, to further monitor fetal outcomes of pregnant women exposed to Myfortic, a National Transplantation Pregnancy Registry has been established. The FDA is encouraging doctors to register their female Myfortic patients by calling 1-877-955-6877.