Purpose Azacitidine (AZA) is the current standard of care for high-risk (ie, International Prognostic Scoring System high or intermediate 2) myelodysplastic syndrome (MDS), but most patients will experience primary or secondary treatment failure. The outcome of these patients has not yet been described. Patients and Methods Overall, 435 patients with high-risk MDS and former refractory anemia with excess blasts in transformation (RAEB-T) were evaluated for outcome after AZA failure. The cohort of patients included four data sets (ie, AZA001, J9950, and J0443 trials and the French compassionate use program). Results The median follow-up after AZA failure was 15 months. The median overall survival was 5.6 months, and the 2-year survival probability was 15%. Increasing age, male sex, high-risk cytogenetics, higher bone marrow blast count, and the absence of prior hematologic response to AZA were associated with significantly worse survival in multivariate analysis. Data on treatment administered after AZA failure were available for 270 patients. Allogeneic stem-cell transplantation and investigational agents were associated with a better outcome when compared with conventional clinical care. Conclusion Outcome after AZA failure is poor. Our results should serve as a basis for designing second-line clinical trials in this population.

Prognostic factors for response and survival in higher-risk myelodysplastic syndrome patients treated with azacitidine (AZA) remain largely unknown. Two hundred eighty-two consecutive high or intermediate-2 risk myelodysplastic syndrome patients received AZA in a compassionate, patient-named program. Diagnosis was RA/RARS/RCMD in 4%, RAEB-1 in 20%, RAEB-2 in 54%, and RAEB-t (AML with 21%-30% marrow blasts) in 22%. Cytogenetic risk was good in 31%, intermediate in 17%, and poor in 47%. Patients received AZA for a median of 6 cycles (1-52). Previous low-dose cytosine arabinoside treatment (P ‫؍‬ .009), bone marrow blasts > 15% (P ‫؍‬ .004), and abnormal karyotype (P ‫؍‬ .03) independently predicted lower response rates. Complex karyotype predicted shorter responses (P ‫؍‬ .0003). Performance status > 2, intermediate-and poor-risk cytogenetics, presence of circulating blasts, and red blood cell transfusion dependency > 4 units/8 weeks (all P < 10 ؊4 ) independently predicted poorer overall survival (OS). A prognostic score based on those factors discriminated 3 risk groups with median OS not reached, 15.0 and 6.1 months, respectively (P < 10 ؊4 ). This prognostic score was validated in an independent set of patients receiving AZA in the AZA-001 trial (P ‫؍‬ .003). Achievement of hematological improvement in patients who did not obtain complete or partial remission was associated with improved OS (P < 10 ؊4 ). In conclusion, routine tests can identify subgroups of patients with distinct prognosis with AZA treatment. (Blood. 2011; 117(2):403-411)

Transformation of Philadelphia (Ph)-negative myeloproliferative neoplasms (MPNs