Birth defects as one of Topamaxs potential risks will be included in the warning label on the anticonvulsants packaging after the US Food and Drug Administration (FDA) asked it of the drugs manufacturer Ortho-McNeil, a subsidiary of Johnson & Johnson. The agency wanted to further strengthen its warnings after several studies link the drug to birth defects especially oral clefts when taken during pregnancy prompted it to caution healthcare professionals in prescribing Topamax to all women of childbearing age.
Topamaxs relation to Sudden Unexpected Death in Epilepsy most commonly known as SUDEP is also another side effect that the drug users are looking out for.
A review of pregnancy databases according to the agency showed a higher risk for cleft lip and cleft palate. When parts of the lip or palate don't completely fuse early in the first trimester; that is when the problem occurs, when women may not know they are pregnant. The use of an effective birth control method for women undergoing the Topamax treatment is recommended by the FDA aside from the use of alternative medications that have a lower risk of birth defects.
Marketing of Topamax for epilepsy treatment was began by Ortho-McNeil Pharmaceutical in 1996, and for the prevention of certain types of migraine headaches in 2004. Recent FDA data showed that more than 32 million Topamax prescriptions have been filled since 2007. FDA issued a warning 15 years later after several studies reported the drugs association with oral cleft birth defects.
In the first trimester of pregnancy, data from the North American Antiepileptic Drug Pregnancy Registry showed that the problem occurred in 1.4 percent of infants exposed to topiramate alone. In comparison to a rate of 0.38 percent to 0.55 percent in infants exposed to other antiepileptic drugs. Infants of mothers without epilepsy or related treatments had a prevalence of 0.07 percent. The finding is supported by similar data from the United Kingdom Epilepsy and Pregnancy Register, according to the FDA.
The FDA also just recently elevated Topamaxs classification from pregnancy category C to D which means there is an evidence of fetal risk among humans. Topamax brought in $2.7 billion in revenue for Johnson & Johnson in 2008, before losing patent protection the following year and dropping to $538 million last year. The company paid a fine of $81.5 million after pleading guilty last year to promoting Topamax for unapproved uses.
Johnson & Johnson said it is working with the FDA on the update, noting that the Topamax label already outlines the risks of using the drug during pregnancy and recommends caution in such circumstances. Most serious Topamax side effects discovered so far are the birth defects.
