FDA revises finasteride labels

The labels of 2 formulations of finasteride, used to treat enlarged prostate and male-pattern baldness, are being revised to indicate that additional sexual side effects may persist after the drug has been discontinued, FDA announced.

Finasteride 5 mg (Proscar, Merck) was approved by the FDA in 1992 for the treatment of symptoms related to enlarged prostate. Finasteride 1 mg (Propecia, Merck) was approved by the FDA in 1997 for the treatment of male-pattern hair loss in males only.

Some sexual side effects were reported during clinical trials and were included on the labels when the drugs were initially approved.  The labels were expanded in 2011 to include erectile dysfunction, which some reported persisted after they discontinued the drug.

The latest changes reflect information gained through post-marketing reports, and submitted to the FDA’s Adverse Events Reporting System (AERS) and Merck’s worldwide safety database.

The Propecia label was revised to include libido disorders, ejaculation disorders, and orgasm disorders. A review of post-marketing reports submitted to the AERS database showed that 59 of 421 individuals reported 1 of these sexual dysfunctions lasting for at least 3 months after discontinuing the drug.

The Proscar label was revised to include decreased libido. Information submitted to Merck’s worldwide safety database showed that 68 cases of decreased libido and 131 cases of erectile dysfunction were associated with the use of this drug formulation and lasted for at least several weeks after discontinuation.

Both labels were revised to include a description of reports of male infertility and/or poor semen quality that normalized or improved after drug discontinuation. Merck’s worldwide safety database identified 251 cases with these reports, 13 of which contained enough information for FDA to evaluate. There was limited information available to assess the effect of the drug on semen quality.

“Despite the fact that clear causal links between finasteride and sexual adverse events have NOT been established, the cases suggest a broader range of adverse effects than previously reported in patients taking these drugs,” FDA wrote in its statement.

“Information about these adverse events may be important to individual patients. Therefore, prescribers and patients need to be aware of them, as part of a discussion of risk and benefits of finasteride when determining the best treatment options.”