How routine pharmacovigilance failed to identify finasteride’s persistent sexual side effects

When confronted with data that their product could cause persistent erectile dysfunction, the Risk Management Safety Team at Merck, in 2009, had the opportunity to take further action to sort out the issue. Realizing that many adverse event reports lacked adequate information, the team could have recommended conducting additional rigorous prospective studies on finasteride to obtain needed information using validated instruments to assess sexual symptoms. Instead of seeking out the truth regarding a serious and life-altering adverse effect, the Risk Management Safety Team’s planned action was routine pharmacovigilance for another 2 years. It is difficult to justify this decision since routine pharmacovigilance was unable to provide adequate information on hundreds of cases from 1998 to 2008. The FDA also bears some responsibility as it did not advise or requireMerck to conduct additional safety studies to adequately address the signal of persistent
erectile dysfunction.

Irwig MS. doi: 10.1111/andr.13122 [Andrology]