Bayer stops trial of drug it hopes will be a blockbuster

Dec. 5, 2018

Bayer has halted testing for vilaprisan, a new medication developed to treat uterine fibroids. The company said that it’s concerned about the risk of side effects uncovered in toxicology data. 

“We recently observed safety signals in pre-clinical toxicological studies in rodents investigating long term safety of vilaprisan — a drug candidate we develop for the treatment of uterine fibroids and endometriosis,” Bayer stated. “Although these are preliminary pre-clinical findings that have not been observed in other vilaprisan studies we decided as a precautionary measure to pause recruitment in the ongoing clinical studies with vilaprisan until a thorough analysis of the findings has been achieved.”

Bayer had predicted that peak annual sales for vilaprisan could reach $1.1 billion. 

Read the full Reuters report.