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

bluebird bio, Inc. (symbol: BLUE) was one of the worst losers of the
trading day today (2016-04-20), losing -7.15%. The number of shares that
changed hands was 3,054,707, or about 2 times the average daily volume in
the stock.
The closing price was $44.31, amounting to a market cap of $1,640,000,000,
about -77.55% off the highest price in the last 12 months. The stock has
been trading at a range between $37.4 and $197.35.
BLUE is in the Biotechnology: Biological Products (No Diagnostic
Substances) industry, part of the Health Care sector. It first went public
in 2013.