Transplant rejection drug boosts the risk of birth defects

Authorities in the United States have issued a warning with regard to a drug used to prevent the rejection of transplanted organs.

The Food and Drug Administration (FDA) says the drug CellCept used to help prevent kidney, liver and heart transplant rejection, boosts the risk of first trimester pregnancy loss and increases the risk of congenital malformations.

In future the drug will carry a new warning changed from Category C (risk of fetal harm cannot be ruled out) to Category D (positive evidence of fetal risk).

The congenital malformations include in particular, external ear and facial abnormalities including cleft lip and palate, and abnormalities of the distal limbs, heart, esophagus, and kidneys.

The FDA says data collected from a national registry prompted the new warnings and CellCept should not be given until a negative pregnancy test is confirmed within one week prior to therapy.

According to the FDA the drug reduces blood levels of the hormones in the oral contraceptive pill and may therefore reduce the effectiveness of birth control pills.

The FDA warning cites a review of postmarketing data from 1995 to 2007 that found among 77 women exposed to the drug, 25 had a spontaneous abortion and 14 had a deformed infant or fetus.

The FDA says because dangerous side effects are reported voluntarily to the FDA, it is often difficult to determine how common the adverse outcomes actually are.

The FDA says animal studies of the drug did find some signs of fetal defects.

Roche and FDA have notified healthcare providers about the warning

The FDA also warns that women of childbearing potential (including pubertal girls and peri-menopausal woman) taking CellCept must receive contraceptive counseling and use effective contraception.