Abstract OT1-01-09: Feasibility and safety of avoiding granulocyte colony-stimulating factor prophylaxis during the paclitaxel portion of dose dense doxorubicin-cyclophosphamide and paclitaxel regimen

Abstract

Background: The need for granulocyte-colony stimulating factor (G-CSF) support during dose-dense (DD) paclitaxel (T) after doxorubicin and cyclophosphamide (AC) is unclear. Given that G-CSF is not devoid of adverse effects, and adds significant costs to treatment, we are examining the feasibility and safety of avoiding G-CSF during dose dense T. Methods: This is a single center, single-arm, phase II, two stage study. The primary aim is to evaluate the rate of T treatment completion within 7 weeks (from D1 of cycle 1 to D1 of cycle 4 of T) omitting Pegfilgrastim using pre-specified safety rules. Secondary aims include: characterization of the utilization of Pegfilgrastim using pre-specified safety rules in patients receiving dose dense T; evaluation of the safety of omitting routine Pegfilgrastim support in patients receiving dose dense T; evaluation of total cost ($ United States) of omitting routine Pegfilgrastim use during dose dense T. As a secondary aim we will evaluate the safety of simplifying the pre-medication regimen used for the T portion of the regimen (withholding corticosteroids in cycle 3 and 4 if no evidence of allergic reactions in cycle 1 and 2). A Simon Optimal design was selected with an overall one-side type I error of 10% and 90% power to detect the difference between unacceptable T completion rate (75%) and desirable completion rate (85%). In the first stage, 51 evaluable patients will be enrolled. If during the first stage, at any point, a total of 12 or more patients do not complete treatment within 7 weeks the trial will be closed permanently. Among the 51 patients enrolled after the first stage, if at least 40 patients complete treatment without dose delay, accrual will continue to the second stage where an additional 74 evaluable patients will be enrolled. If there are at least 100 among the 125 evaluable patients completing treatment without dose delay, the regimen will be considered worthy of further study. If during the second stage, at any point, a total of 26 patients do not complete treatment within 7 weeks the trial will be closed permanently and the study intervention will not be of clinical interest. If the true treatment completion rate is 75%, the chance the regimen is declared ineffective is 91% (exact alpha = 0.094) and if the true treatment completion rate is 85% the chance that the regimen is falsely declared ineffective is 10% (exact power = 0.899). The estimated accrual rate is 6-8 patients/month. Accrual started in April 2016. Clinical trial information: NCT02698891. Citation Format: Barroso-Sousa R, Vaz-Luis I, Guo H, Barry WT, Brackett AM, Brock VA, Roche KA, Kasparian E, Winer EP, Lin NU. Feasibility and safety of avoiding granulocyte colony-stimulating factor prophylaxis during the paclitaxel portion of dose dense doxorubicin-cyclophosphamide and paclitaxel regimen [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-01-09.