The MDS Beacon™

Turkish researchers showed that myelodysplastic syndromes (MDS) patients responded best to Vidaza (azacitidine) when it was taken as a front-line therapy. The results of the study were presented at the 45th meeting of the American Society for Clinical Oncology (ASCO).

The study followed 26 patients who were diagnosed as having Intermediate-1, Intermediate-2, or high risk MDS. They were treated with Vidaza from 2002 to 2008 and received a median of two cycles.

At the end of the study, seven of the 26 patients were ineligible for evaluation. Ten (53 percent) of the remaining 19 patients responded positively to the treatment, four of whom reached complete remission, which is defined by the International Working Group as having a blood count of more than 1,000 neutrophils per µL and more than 100,000 platelets per µL. Patients that achieve complete remission often show no symptoms even after a thorough examination. However, the diagnosis does not necessarily mean that MDS is fully cured or that there are no cancer cells in the body. Two of the ten patients who responded positively reached partial remission, while four minimally improved their blood cell counts. Nine of the remaining 19 patients (47 percent) did not show any response to treatment.

The patients who reached remission had significantly higher numbers of thrombocytes, received more cycles of treatment, and had lower serum ferritin levels than patients who did not respond to Vidaza. Ferritin, an iron-storage protein that prevents iron from forming free radicals, corresponds to blood iron levels. MDS patients who undergo repeated transfusions are at risk for high serum ferritin and often take iron chelators to remove excess iron from the body.

Responses largely varied on whether patients were given Vidaza as the first choice of therapy. From patients who received Vidaza as a front-line treatment, 71 percent of patients showed a significant response, while 29 percent of patients did not. Characteristics that did not affect patient responses included age, sex, and pre-treatment leukocyte, hemoglobin, and neutrophil counts.

Researchers concluded that response to Vidaza depended most significantly on whether patients had previously received a different treatment, what their initial thrombocyte count and serum ferritin levels were, and the number of cycles that were administered.

For more information, please see abstract e18003 at the 2009 ASCO meeting Web site.