$ACAD is one of biggest losers #stocks today. read more:

ACADIA Pharmaceuticals Inc. (symbol: ACAD) was one of the worst losers of
the trading day today (2016-01-13), losing -14.46%. The number of shares
that changed hands was 3,732,610, or about 3 times the average daily volume
in the stock.
The closing price was $23.13, amounting to a market cap of $2,330,000,000,
about -55.51% off the highest price in the last 12 months. The stock has
been trading at a range between $22.74 and $51.99.
ACAD is in the Major Pharmaceuticals industry, part of the Health Care
sector. It first went public in 1985.