Vanda Pharmaceuticals Inc's (NASDAQ:VNDA) Fanapt (iloperidone) tablets received FDA approval for the acute treatment of manic or mixed episodes associated with bipolar I disorder in adults. This approval expands Fanapt's market, previously approved for schizophrenia treatment since 2009. Bipolar disorder affects approximately 2.8% of the U.S. adult population, with a significant portion classified as severe. The approval was based on a pivotal study showing statistically significant improvement in patients treated with Fanapt over placebo. Despite this positive development, Vanda's net product sales for 2023 decreased by 4% Y/Y, with sales of another major drug, Hetlioz, declining due to increased competition. VNDA shares surged 27.9% in premarket trading following the announcement.