U.S. Magistrate Judge Marianne B. Bowler denied motions by 14 drug companies, including Bristol-Myers Squibb Co., and Eli Lilly & Co., to exclude expert testimony that prenatal exposure to the anti-miscarriage drug diethylstilbestrol (DES), increased the risk of breast cancer in women over the age of 40, Law 360 reported.
The drug companies had claimed that the testimony did not meet admissibility standards established under the U.S. Supreme Court in the 1993 Daubert v. Merrell Dow Pharmaceuticals Inc., decision. However, Judge Bowler ruled that plaintiffs adequately supported the expert testimony.
In 1971, DES was associated with a rare form of vaginal cancer in female children of women who used DES while pregnant to prevent premature birth or miscarriage. Since then, the FDA has revealed that women who used DES had a 30 percent higher risk of developing breast cancer, and that sons born to mothers who used DES when pregnant had a higher risk of developing noncancerous epididymal cysts. Studies have shown that female children born to mothers who used DES also have a higher risk of developing breast cancer after the age of 40.
In 1975, market approval for DES was revoked for DES at doses of 25 milligrams or higher, and the FDA issued warning labels on lower doses of DES. In 1997, the DES was no longer being made or sold in the US.
The lawsuit alleges negligent failure to warn, negligent failure to test, breach of warranty, and misrepresentation. The suit seeks to establish a class of women born between 1948 and 1972, who were exposed to DES in utero, and were diagnosed with breast cancer after age 40.