Median PFS was 12.4 months with B+CP and 7.9 months with Pl + CP ( HR , 0.27 ; 95 % CI , 0.12 to 0.63 ) in EGFR mutation-positive tumors and 8.3 and 5.6 months , respectively ( HR , 0.33 ; 95 % CI , 0.21 to 0.53 ) , in wild-type tumors .