The MDS Beacon™

At the 45th meeting of the American Society for Clinical Oncology (ASCO), researchers presented a Phase 2 study showing that Nplate (romiplostim) is effective in treating thrombocytopenia, a condition that causes low platelet counts in the blood. Researchers showed that Nplate raised platelet counts and decreased the need for platelet transfusions for patients with low and intermediate-1 risk myelodysplastic syndromes (MDS).

Thrombocytopenia is a common symptom of MDS, and the only current treatment option is a platelet transfusion. Platelets are responsible for blood clotting, and low levels can cause nosebleeds, bleeding gums, rashes of small red dots, and flat, pinpoint bruises. These symptoms are normally treated by platelet transfusions. Nplate is a protein that stimulates platelet production, decreasing the need for transfusions.

The trial included 28 patients with low or intermediate-1 risk MDS with a low platelet count. The average patient was 71 years old, and 68 percent had received platelet transfusions in the year prior to participating in the study. Patients received 750 µg Nplate weekly or biweekly by subcutaneous injection or bi-weekly by intravenous infusion. The average length of treatment was 12 weeks; treatments ranged from four weeks of weekly subcutaneous injection to 20 weeks of biweekly subcutaneous injection.

Sixty-five percent of patients who completed eight weeks of treatment, regardless of schedule, achieved a platelet response, which is defined by the International Working Group criteria as a minimum of 100,000 platelets per µL of blood or an increase of at least 30,000 platelets per µL during treatment. Sixty-one percent of patients completing eight weeks of treatment did not require any platelet transfusions during the therapy. Patients experienced fatigue (18 percent) and headaches (18 percent), and two patients progressed to acute myeloid leukemia.

The small number of study participants limited the ability to compare treatment schedules. However, researchers concluded Nplate is effective in raising platelet counts and decreases the need for transfusions for low and intermediate-1 risk MDS patients. They recommend future studies use 750 µg Nplate administered weekly or bi-weekly by subcutaneous injection.

For more information, please visit abstract 7009 on the 2009 ASCO meeting Web site.