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

PTC Therapeutics, Inc. (symbol: PTCT) was one of the worst losers of the
trading day today (2015-11-19), losing -13.15%. The number of shares that
changed hands was 1,484,860, or about 1 times the average daily volume in
the stock.
The closing price was $30.12, amounting to a market cap of $1,020,000,000,
about -61.74% off the highest price in the last 12 months. The stock has
been trading at a range between $22.67 and $78.72.
PTCT is in the Major Pharmaceuticals industry, part of the Health Care
sector. It first went public in 2013.