The MDS Beacon™

Results from a recent study suggest that treatment with Vidaza or Dacogen is effective for myelodysplastic syndromes patients before they receive donor stem cell transplants. Researchers from South Korea presented these findings at the 2010 European Hematology Association (EHA) Congress.

Stem cell transplantation in which abnormal bone marrow is replaced with healthy donor marrow is the only therapy known to cure myelodysplastic syndromes (MDS). Vidaza (azacitidine) and Dacogen (decitabine), similar types of drugs that both suppress MDS, can be used to reduce the number of diseased blood cells in the marrow prior to transplantation.

According to Dr. Je-Hwan Lee a professor at the Asan Medical Center in Seoul, South Korea, and one of the researchers, “Stem cell transplantation is now increasingly used for MDS patients. Strategies such as Vidaza or Dacogen can help to prevent disease progression and hopefully improve disease status, until transplantation can be performed.”

Seventy-five MDS patients were treated once daily for seven days with 75 mg/m² Vidaza or once daily for five days with 20 mg/m² Dacogen every four weeks. The researchers monitored blood counts, bone marrow, and changes in the patients’ chromosomes.

Nineteen of the patients had matching donors and went on to receive stem cell transplants, a median of 6.5 months after beginning treatment with Vidaza or Dacogen. Of those 19 patients, 9 were treated with Dacogen, and 10 were treated with Vidaza.

After treatment with Vidaza or Dacogen, 43 percent of patients who were evaluated achieved at least a complete response in the bone marrow, but 16 percent progressed from MDS to acute myeloid leukemia (AML). Progression to AML negatively impacted survival.

The only significant difference between treatment with Vidaza and Dacogen was the median number of cycles: 5.5 cycles of Vidaza and 3 cycles of Dacogen. The majority of patients indicated that they stopped treatment because they were planning to receive a stem cell transplant.

Stem cell transplantation successfully resulted in the growth of new neutrophils, a type of white blood cell, in 95 percent of transplant patients and the growth of new platelets, blood cells responsible for clotting, in 79 percent of patients. Two patients required a red blood cell transfusion, and one patient required a platelet transfusion after day 100 following transplantation.

Two years after transplantation, 68 percent of patients were still alive, and 78 percent of those patients remained relapse-free.

As is often a complication with donor stem cell transplants, 42 percent of participants experienced acute graft-vs-host disease, and 26 percent experienced a chronic case of the disease. Graft-vs-host disease occurs when the new stem cells attack the patients’ cells as foreign.

Researchers concluded that Vidaza or Dacogen treatment is effective before donor stem cell transplantation. However, further study is required to show that pre-treatment with Vidaza or Dacogen improve the outcome of patients receiving transplants.

Dr. Lee said, “We will analyze our data further to determine the influence complete response or marrow complete response to Vidaza or Dacogen has on the post-transplant outcomes.”

For more information, please see abstract 0319 at the EHA meeting website.