Patients in the observation group who crossed over to receive Vidaza treatment (47 patients) had a response rate of 12.8%.

A multi-center, open-label, single-arm study of 72 patients with RAEB, RAEB-T, CMMoL, or AML was also carried out. Treatment with subcutaneous Vidaza resulted in a response rate (CR + PR) of 13.9%, using criteria similar to those described above. The mean and median duration of clinical response of PR or better was estimated as 810 and 430 days, respectively; 80% of the responding patients were still in PR or better at the time of completion of study involvement. In another open-label, single-arm study of 48 patients with RAEB, RAEB-T, or AML, treatment with intravenous Vidaza resulted in a response rate of 18.8%, again using criteria similar to those described above. The mean and median duration of clinical response of PR or better was estimated as 389 and 281 days, respectively; 67% of the responding patients were still in PR or better at the time of completion of treatment. Response occurred in all MDS subtypes as well as in patients with adjudicated baseline diagnosis of AML in both of these studies. Vidaza dosage regimens in these 2 studies were similar to the regimen used in the controlled study.

Benefit was seen in patients who did not meet the criteria for PR or better, but were considered “improved.” About 24% of Vidaza-treated patients were considered improved, and about 2/3 of those lost transfusion dependence. In the observation group, only 5/83 patients met criteria for improvement; none lost transfusion dependence. In all three studies, about 19% of patients met criteria for improvement with a median duration of 195 days.

Response rate estimates were similar regardless of age or gender.

INDICATIONS AND USAGE

Vidaza is indicated for treatment of patients with the following myelodysplastic syndrome subtypes: refractory anemia or refractory anemia with ringed sideroblasts (if accompanied by neutropenia or thrombocytopenia or requiring transfusions), refractory anemia with excess blasts, refractory anemia with excess blasts in transformation, and chronic myelomonocytic leukemia.

CONTRAINDICATIONS

Vidaza is contraindicated in patients with a known hypersensitivity to azacitidine or mannitol. Vidaza is also contraindicated in patients with advanced malignant hepatic tumors. (See PRECAUTIONS).

WARNINGS

Pregnancy - Teratogenic Effects: Pregnancy Category D

Vidaza may cause fetal harm when administered to a pregnant woman. Early embryotoxicity studies in mice revealed a 44% frequency of intrauterine embryonal death (increased resorption) after a single IP (intraperitoneal) injection of 6 mg/m2 (approximately 8% of the recommended human daily dose on a mg/m2 basis) azacitidine on gestation day 10. Developmental abnormalities in the brain have been detected in mice given azacitidine on or before gestation day 15 at doses of ~3-12mg/m2 (approximately 4%-16% the recommended human daily dose on a mg/m2 basis).

In rats, azacitidine was clearly embryotoxic when given IP on gestation days 4-8 (postimplantation) at a dose of 6mg/m2 (a