Study of Azacitidine to Evaluate Safety and Effectiveness for Chinese Patients With Higher Risk Myelodysplastic Syndrome

Hematologic Response is defined by those participants who experienced a Complete Response, Partial Response and Stable Disease (SD) based on IWG 2000 response criteria for MDS. CR = repeat bone marrow (BM) shows <5% myeloblasts, and peripheral blood values lasting ≥ 2 months of hemoglobin (hgb) (>110 g/L), neutrophils (≥1.5x10^9/L), platelets (≥100x10^9/L), blasts (0%) and no dysplasia • PR = same as CR for peripheral blood: BM shows blasts decrease by ≥ 50% or a less advanced FAB classification from pretreatment • Stable disease (SD): failure to achieve a PR, no evidence of progression for at least 2 months. • Failure: death during treatment or disease progression • Relapse After CR or PR: return to pretreatment BM blast percent or decrement of ≥ 50% from remission/response levels in granulocytes or platelets; or reduction in hgb by ≥20 g/L or transfusion dependence • Disease Progression: change in blast levels • Disease Transformation to Acute Myelogenous Leukemia.

Hematologic Response is defined by those participants who experienced a Complete Response, Partial Response and Stable Disease (SD) based on IWG 2000 response criteria for MDS. CR = repeat bone marrow (BM) shows <5% myeloblasts, and peripheral blood values lasting ≥ 2 months of hemoglobin (hgb) (>110 g/L), neutrophils (≥1.5x10^9/L), platelets (≥100x10^9/L), blasts (0%) and no dysplasia • PR = same as CR for peripheral blood: BM shows blasts decrease by ≥ 50% or a less advanced FAB classification from pretreatment • Stable disease (SD): failure to achieve a PR, no evidence of progression for at least 2 months. • Failure: death during treatment or disease progression • Relapse After CR or PR: return to pretreatment BM blast percent or decrement of ≥ 50% from remission/response levels in granulocytes or platelets; or reduction in hgb by ≥20 g/L or transfusion dependence • Disease Progression: change in blast levels • Disease Transformation to Acute Myelogenous Leukemia.

Hematologic improvements (HI) have 4 categories: 1. Erythroid response (HI-E): Major >20g/L increase or transfusion independent. Minor: 10-20g/L increase or ≥50% decrease in transfusion requirements. 2. Platelet response (HI-P): Major absolute increase of ≥30x10^9/L or platelet transfusion independence. Minor: ≥50% increase. 3. Neutrophil response (HI-N): Major 100% increase or an absolute increase of >0.5x10^9/L. Minor: ≥100% increase and absolute increase of <0.5x10^9/L 4. Progression or relapse after HI Hematological improvement (HI) was defined as any type (major or minor) of improvement of HI-E, HI-P, or HI-N. Criteria: Pretreatment=hemoglobin <100g/L or RBC transfusion-dependent, platelet count <100x10^9/L or platelet transfusion dependent, absolute neutrophil count <1.5x10^9/L. Sponsor's determination was derived using clinically relevant data. Denominator for progression/relapse after HI included participants who had achieved HI.

The number of units of platelet transfusions received 56 days prior to treatment, considered the baseline period, (baseline period defined as the screening period before the date of the first dose of azacitidine; any laboratory and blood transfusion data reported on the day of the first dose of azacitidine was considered to be baseline data) and during study was standardized per 28 days and summarized by cycle for platelets. The formula for standardizing per 28 days was: [(# of transfusions in the measurement period / length of the measurement period (days)) x 28], where the measurement period was either baseline or the relevant cycle length.

The number of platelet transfusions received 56 days prior to treatment, considered the baseline period (baseline period defined as the screening period before the date of the first dose of azacitidine; any laboratory and blood transfusion data reported on the day of the first dose of azacitidine was considered to be baseline data) and during study was standardized per 28 days and summarized by cycle for platelets. The formula for standardizing per 28 days was: [(# of transfusions in the measurement period / length of the measurement period (days)) x 28], where the measurement period was either baseline or the relevant cycle length.

The number of units of RBC received 56 days prior to treatment, considered the baseline period (baseline period defined as the screening period before the date of the first dose of azacitidine; any laboratory and blood transfusion data reported on the day of the first dose of azacitidine was considered to be baseline data) and during study was standardized per 28 days and summarized by cycle for RBC. The formula for standardizing per 28 days was: [(# of transfusions in the measurement period / length of the measurement period (days)) x 28], where the measurement period was either baseline or the relevant cycle length.

The number of RBC transfusions received 56 days prior to treatment, considered the baseline period (baseline period defined as the screening period before the date of the first dose of azacitidine; any laboratory and blood transfusion data reported on the day of the first dose of azacitidine was considered to be baseline data) and during study was standardized per 28 days and summarized by cycle for platelets. The formula for standardizing per 28 days was: [(# of transfusions in the measurement period / length of the measurement period (days)) x 28], where the measurement period was either baseline or the relevant cycle length.

The on-treatment adverse event of infection requiring IV antibiotics, antifungals, or antivirals per 28 days/cycle. The overall post-baseline average is the average of number of infections requiring IV antibiotics or IV antiviral per 28 days/cycle.

Overall survival is defined as time to death from any cause, is calculated using date of first dose and date of death, or date of last follow-up for censored participants. Those, who die regardless of the cause of death, will be considered to have an event.

A treatment-emergent adverse events (TEAE) was defined as AEs with an onset date on or after the date of first dose and within 28 days after the date of the last dose. Any AE that occurred beyond this timeframe and was assessed by the investigator as possibly related to study drug was considered treatment-emergent. The intensity and severity of AEs was assessed by the investigator according to the Common Terminology Criteria for Adverse Event (CTCAE) Version 4.0. For any AEs not listed in the CTCAE grading system, the intensities of these events was assessed by the Investigator using the 5-point scale: Grade 1 = Mild, Grade 2 = Moderate; Grade 3 = Severe, Grade 4 = Life threatening, Grade 5 = Death. An SAE is any AE occurring that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, and constitutes an important medical event.

Area under the plasma concentration-time curve from time zero to infinity (AUC∞) following multiple doses of Azacitidine on Day 7; if possible, the area under the concentration-time curve from time zero to infinity, calculated by the linear trapezoidal rule and extrapolated to infinity was calculated according to the following equation: AUC∞ = AUCt + (Ct/ λz ), where Ct is the last quantifiable concentration. No AUC extrapolation will be performed with unreliable λz. If % AUC extrapolated is ≥ 25%, AUC∞ will not be reported

Area under the plasma concentration-time curve from time zero to the last quantifiable time point, calculated by the linear trapezoidal rule when concentrations are increasing and the logarithmic trapezoidal method when concentrations are decreasing.

The observed maximum plasma concentration obtained directly from the observed concentration versus time data.

Time to maximum observed plasma concentration obtained directly from the observed concentration versus time data.

The apparent terminal half-life was calculated according to the following equation t½ = 0.693/λz.

Apparent total plasma clearance (CL/F) of Azacitidine was calculated as Dose/AUC∞

Apparent volume of distribution, was calculated according to the equation: Vd/F = (CL/F)/λz

A treatment-emergent adverse events (TEAE) was defined as AEs with an onset date on or after the date of first dose and within 28 days after the date of the last dose. Any AE that occurred beyond this timeframe and was assessed by the investigator as possibly related to study drug was considered treatment-emergent. The intensity and severity of AEs was assessed by the investigator according to the Common Terminology Criteria for Adverse Event (CTCAE) Version 4.0. For any AEs not listed in the CTCAE grading system, the intensities of these events was assessed by the Investigator using the 5-point scale: Grade 1 = Mild, Grade 2 = Moderate; Grade 3 = Severe, Grade 4 = Life threatening, Grade 5 = Death. An SAE is any AE occurring that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, and constitutes an important medical event.