(A) Overall survival of the patients who were assigned to receive IFN- and were alive and in chronic phase after 8 months, when the hematologic response was assessed (landmark analysis). The patients who achieved a complete hematologic response (n = 114) survived more. Log-rank test, P = .0001. (B) Overall survival of the patients who were assigned to receive IFN- and were alive and in chronic phase after 24 months when the cytogenetic response was assessed (landmark analysis). The patients who achieved a complete or major cytogenetic response during the first 24 months (n = 34) survived longer. Log-rank test, P = .001.