A Phase II Study of ABT-888, an Inhibitor of Poly(ADP-ribose) Polymerase (PARP) in Combination With Temozolomide in Patients With Heavily Pretreated, Metastatic Colorectal Cancer
We will initiate a single arm, open label Phase II study to test the clinical activity of
ABT-888 and temozolomide in patients with metastatic colorectal cancer.
Treatment will continue weekly with restaging scans to be performed every 8 weeks. The trial
will follow a Simon's two-stage optimal design. For the first stage, 21 patients will be
accrued. If two (9.5%) or fewer of the 21 patients exhibit a partial or complete response
with ABT-888 plus temozolomide, the agent will be rejected and the trial stopped. However,
if at least 3 patients of the 21 (14%) exhibit a response in the first stage, then an
additional 29 patients will be entered into the second stage, for a total of 50 patients in
this phase II study. If 8 (16%) or more patients exhibit a response, then the treatment will
be considered for further investigation. The sample sizes of 21 and 50 patients and the
decision rules, in stages 1 and 2 respectively, are designed to differentiate a 25% overall
response rate from a 10% overall response rate.
Allocation: Non-Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
Disease control rate defined as stable disease, partial response, or complete response according to the Response Evaluation Criteria in Solid Tumors (RECIST).
Michael J Pishvaian, MD, PhD
United States: Food and Drug Administration
|Georgetown University Medical Center||Washington, District of Columbia 20007|