Statement: The Percentage of Participants With Feasibility was 10% higher in cohort 1 of the primary trial than in cohort 2.
Primary_evidence: Outcome Measurement:    Percentage of Participants With Feasibility   The regimen was considered feasible if the participant was able to complete the eribulin portion without dose delay or reduction. Dose delay was defined as a delay due to eribulin-related adverse event (AE) for more than 2 days for subsequent doses (cycles after the initiation of full dose of eribulin, except holidays, scheduling difficulties and nonclinical logistical issues). If a participant had more than 1 dose omission, delay or reduction due to eribulin-related AE, these events were collectively counted as one entity in the same participant. Participants were followed for approximately 3 years after the last dose of the study treatment. Feasibility rates were calculated with or without growth factor support. In both cohorts, the percentage of participants who completed the eribulin portion of the regimen without a dose omission, delay or reduction due to eribulin-related AE was estimated via the observed completion rate and an exact 90% confidence interval (CI) was constructed.   Time frame: From date of first dose, up to 3 years after the last dose of study treatment, or up to approximately 4 years 2 months Results 1:    Arm/Group Title: Cohort 1: Eribulin Mesylate With Filgrastim as Needed   Arm/Group Description: Participants initially received doxorubicin (60 mg/m^2) plus cyclophosphamide (600 mg/m^2) intravenously (IV) on Day 1, of every 14-day cycle for 4 cycles. Eribulin mesylate was administered following the doxorubicin plus cyclophosphamide regimen at a dose of 1.4 mg/m^2 IV over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle for 4 cycles (Cycles 5 to 8). In this Cohort growth factors, subcutaneous pegfilgrastim (6 mg) or filgrastim, could be used with eribulin therapy at the physician's discretion if neutropenia occurred that recovered to Grade   2.   Overall Number of Participants Analyzed: 54   Measure Type: Number   Unit of Measure: Percentage of participants  70.4        (58.5 to 80.4) Results 2:    Arm/Group Title: Cohort 2: Eribulin Mesylate With Prophylactic Filgrastim   Arm/Group Description: Participants initially received doxorubicin (60 mg/m^2) plus cyclophosphamide (600 mg/m^2) IV on Day 1, of every 14-day cycle for 4 cycles. Eribulin mesylate was administered following the doxorubicin plus cyclophosphamide regimen at a dose of 1.4 mg/m^2 IV over 2 to 5 minutes on Days 1 and 8 of a 21-day cycle for 4 cycles (Cycles 5 to 8). In this Cohort filgrastim was used with eribulin therapy at a dose of 300 micrograms for participants   60 kg or 480 micrograms for participants >60 kg, administered subcutaneously on Days 3 and 4 and Days 10 and 11 of each eribulin cycle.   Overall Number of Participants Analyzed: 25   Measure Type: Number   Unit of Measure: Percentage of participants  60.0        (41.7 to 76.4)