Mersana Therapeutics, Inc. (NASDAQ:MRSN – Get Free Report) saw a significant drop in short interest during the month of May. As of May 15th, there was short interest totalling 8,990,000 shares, a drop of 17.7% from the April 30th total of 10,920,000 shares. Based on an average trading volume of 2,150,000 shares, the days-to-cover ratio […]