First drug to treat hair loss disorder alopecia OK'd by FDA. Jada Pinkett Smith and Rep. Ayanna Presley have it.

The Food and Drug Administration on Monday approved a drug called baricitinib as the first for treating severe alopecia areata, an autoimmune disorder affecting more than 300,000 people in the United States every year.

Alopecia causes either temporary or permanent patchy hair loss that can affect any hair-bearing site of the body, leading to emotional distress. The condition has come to the fore recently through high-profile cases including Hollywood actress Jada Pinkett Smith and Rep. Ayanna Pressley.

"Access to safe and effective treatment options is crucial for the significant number of Americans affected by severe alopecia," said FDA official Kendall Marcus in a statement. "Today's approval will help fulfill a significant unmet need for patients with severe alopecia areata."