With the data for the two chemotherapy regimens combined , the addition of bevacizumab to chemotherapy was associated with increased overall survival ( 17.0 months vs. 13.3 months ; hazard ratio for death , 0.71 ; 98 % confidence interval , 0.54 to 0.95 ; P = 0.004 in a one-sided test ) and higher response rates ( 48 % vs. 36 % , P = 0.008 ) .