Shares of filgotinib developer Galapagos NV (NASDAQ:GLPG) fell 27.5 percent to $44.60 on Friday after Abbvie Inc. declined to exercise its option to in-license the JAK1 inhibitor, electing instead to advance its own same-class candidate, ABT-494. The decision ends a deal first struck in 2012 and returns full filgotinib rights to Galapagos, which said it had anticipated the move.