Yes, it is quite disastrous. However, I think $SVNT has them beat slightly. 52 week high was 23.46 and today it closed at 3.96, which is more than -83.12% down.
DNDN peak was at 57.67 and today's close at 9.91 puts them at -82.8% down since those highs. Curious what Mr. Cohen will do with his gigantic loss at this point.