 Shares of Cortexyme Inc. CRTX, -73.76 tumbled 72.7 in trading on Wednesday, the day after the company said a late-stage clinical trial evaluating its experimental Alzheimers disease treatment failed to meet the studys endpoints. Cortexymes stock is down 43.3 this year; the SP 500 SPX, -0.09 is up 21.8. 