antiquity
09-02-2002, 11:28 AM
Birth Defect Risk Unknown for Most New Drugs
September 02, 2002 10:55:48 AM PST, Reuters
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More than nine-tenths of drugs approved since 1980 have not been properly tested to ensure they do not cause birth defects if taken by pregnant women, study findings show.
According to researchers based at the University of British Columbia in Vancouver, Canada, new drugs must be tested to determine if they cause birth defects in pregnant animals before they are approved by the US Food and Drug Administration ( news - web sites) (FDA).
However, what a drug does in animals is not always what it does in humans, they note--so once a drug is approved, researchers need to track what happens in human patients, and use that information to determine whether pregnant women who take the drug are putting their fetuses at risk.
However, as W.Y. Lo and Dr. J.M. Friedman show, these follow-up studies have not been performed for the vast majority of new drugs. As such, more than 90% of new drugs are still considered to have an "undetermined" risk of producing birth defects, according to the report in the September issue of the journal Obstetrics & Gynecology.
Many women need to take drugs for a variety of reasons during pregnancy, and not knowing the risks of these drugs can be frustrating, Friedman told Reuters Health.
"My experience is that many members of the general public, both pregnant women and their partners, are surprised and frustrated about how little we really know about the safety of medications in pregnancy," Friedman said.
The solution, Friedman offered, is simply to keep track of what effects the drugs cause in pregnant women who take them, either because not doing so would risk their or their babies' health, or because they do not yet know they are pregnant.
"I would like to see an ongoing effort to obtain information about the effects on the baby of maternal use of prescription medications in human pregnancy," the researcher said.
Lo and Friedman base their findings on a review of information on birth defect risk of 468 drugs approved between 1980 and 2000. They found that 91% of these new drugs were designated as carrying an "undetermined" risk of birth defects if taken by pregnant women.
In an interview, Friedman said that the companies that manufacture the drugs often have no financial incentive to conduct further studies on birth defects once the drug is FDA-approved. Proper studies cost money, the researcher noted, and there is usually no regulatory requirement that the companies perform these tests.
Friedman added that it would be "unethical" to conduct a study in which researchers gave pregnant women a drug to see if it produced birth defects.
"However, almost all drugs are taken by some pregnant women," the study author said.
Studies could follow a group of pregnant women and record what medications they take and the subsequent health of their babies, or interview parents of babies with birth defects and determine which medications their mothers took, Friedman suggested.
"The point is that such studies are possible, and I believe that they need to be done on a sufficient scale to learn about the safety of all medications in human pregnancy," Friedman said.
SOURCE: Obstetrics & Gynecology 2002;100:465-473.
September 02, 2002 10:55:48 AM PST, Reuters
Â*
More than nine-tenths of drugs approved since 1980 have not been properly tested to ensure they do not cause birth defects if taken by pregnant women, study findings show.
According to researchers based at the University of British Columbia in Vancouver, Canada, new drugs must be tested to determine if they cause birth defects in pregnant animals before they are approved by the US Food and Drug Administration ( news - web sites) (FDA).
However, what a drug does in animals is not always what it does in humans, they note--so once a drug is approved, researchers need to track what happens in human patients, and use that information to determine whether pregnant women who take the drug are putting their fetuses at risk.
However, as W.Y. Lo and Dr. J.M. Friedman show, these follow-up studies have not been performed for the vast majority of new drugs. As such, more than 90% of new drugs are still considered to have an "undetermined" risk of producing birth defects, according to the report in the September issue of the journal Obstetrics & Gynecology.
Many women need to take drugs for a variety of reasons during pregnancy, and not knowing the risks of these drugs can be frustrating, Friedman told Reuters Health.
"My experience is that many members of the general public, both pregnant women and their partners, are surprised and frustrated about how little we really know about the safety of medications in pregnancy," Friedman said.
The solution, Friedman offered, is simply to keep track of what effects the drugs cause in pregnant women who take them, either because not doing so would risk their or their babies' health, or because they do not yet know they are pregnant.
"I would like to see an ongoing effort to obtain information about the effects on the baby of maternal use of prescription medications in human pregnancy," the researcher said.
Lo and Friedman base their findings on a review of information on birth defect risk of 468 drugs approved between 1980 and 2000. They found that 91% of these new drugs were designated as carrying an "undetermined" risk of birth defects if taken by pregnant women.
In an interview, Friedman said that the companies that manufacture the drugs often have no financial incentive to conduct further studies on birth defects once the drug is FDA-approved. Proper studies cost money, the researcher noted, and there is usually no regulatory requirement that the companies perform these tests.
Friedman added that it would be "unethical" to conduct a study in which researchers gave pregnant women a drug to see if it produced birth defects.
"However, almost all drugs are taken by some pregnant women," the study author said.
Studies could follow a group of pregnant women and record what medications they take and the subsequent health of their babies, or interview parents of babies with birth defects and determine which medications their mothers took, Friedman suggested.
"The point is that such studies are possible, and I believe that they need to be done on a sufficient scale to learn about the safety of all medications in human pregnancy," Friedman said.
SOURCE: Obstetrics & Gynecology 2002;100:465-473.