IO Biotech drops after cancer vaccine narrowly misses main goal of late-stage study

** Shares of biotech firm IO Biotech IOBT.O fall 19.9% to $1.45 after surging over 50% in premarket trading

** Company says patients on its experimental cancer vaccine, in combination with Merck's MRK.N Keytruda, showed improvement in a late-stage study goal, but narrowly missed the main goal as the results did not show statistical significance

** Co says the study data showed that patients on the combination treatment experienced slower disease progression, with a hazard ratio of 0.77; However, the result was not statistically significant, as the p-value of 0.056 was slightly above the threshold of 0.045

** Despite the miss, the vaccine led to improvement in progression-free survival in patients with advanced skin cancer in late-stage study

** Company plans to meet with the U.S. FDA this fall to discuss the data and next steps for a potential regulatory submission

** Including session moves, stock up 61.4% YTD