 Shares of Nkarta Inc. NKTX, 95.82 skyrocketed 92.8 in very active morning trading, enough to make the stock the biggest gainer and most active listed on major U.S. exchanges, after the biopharmaceutical company announced positive results from a Phase 1 trial of its cancer treatments. The rally comes after the stock closed at a record low of 7.77 on Friday. 