Validation of International Working Group response criteria in higher-risk myelodysplastic syndromes: A report on behalf of the MDS Clinical Research Consortium

The utility of the International Working Group (IWG) 2006 response criteria for myelodysplastic syndromes myelodysplastic syndromes: (my-eh-lo-diss-PLASS-tik SIN-dromez) A group of disorders where the bone marrow does not work well, and the bone marrow cells fail to make enough healthy blood cells. Myelo refers to the bone marrow. Dysplastic means abnormal growth or development. People with MDS have low blood cell count for at… (MDS) as a surrogate endpoint for outcomes is unclear. We assessed the validity of the IWG 2006 response criteria in a large cohort of higher-risk MDS patients (pts) treated at centers from the MDS Clinical Research Clinical Research: A type of research that involves individual persons or a group of people. There are three types of clinical research. Patient-oriented research includes clinical trials which test how a drug, medical device, or treatment approach works in people. Epidemiology or behavioral studies look at the… Consortium. The best overall response rate (ORR) by IWG 2006 criteria to first-line therapy among 597 evaluable pts was 38% and include complete response (CR) 16%, marrow CR (mCR) 2%, partial response (PR) 10%, hematological improvement (HI) 10%, stable disease (SD) 33%, and progressive disease (PD) 24%. CR was associated with a better overall survival (OS) compared to all other response groups (P < 0.001). Among 470 pts treated with hypomethylating agent (HMA) as first-line therapy, the overall Response Rate, defined as HI or better was 39%. The median OS from time of best response was 21 mo, 8 mo, 14 mo, 12 mo, 13 mo, and 8 mo for CR, mCR, PR, HI, SD, and PD, respectively (P < 0.001). We validated those results in a separate cohort of 539 higher-risk MDS pts treated at Moffitt Cancer Center who received first-line HMA therapy, particularly addressing the value of mCR and mCR+HI. mCR alone without HI, SD, and PD outcomes were inferior to CR, PR, mCR+HI, and HI. In conclusion, CR by IWG 2006 response criteria can be used as a surrogate endpoint for OS in higher-risk MDS pts. Any response associated with restoration of effective hematopoiesis hematopoiesis: (hi-mat-uh-poy-EE-suss) The process of making blood cells in the bone marrow. is associated with better outcome.