shares of vertex pharmaceuticals inc vrtx shed 023 to 18686 monday on what proved to be an allaround poor trading session for the stock market with the sp 500 index spx falling 000 to 468280 and dow jones industrial average djia falling 004 to 3608745 vertex pharmaceuticals inc closed 5613 below its 52week high 24299 which the company reached on january 25th the stock demonstrated a mixed performance when compared to some of its competitors monday as johnson  johnson jnj fell 090 to 16352 merck  co inc mrk fell 037 to 8369 and abbvie inc abbv fell 011 to 11684 trading volume 10 m remained 522517 below its 50day average volume of 15 m editors note this story was autogenerated by automated insights an automation technology provider using data from dow jones and factset see our market data terms of use