LAUSR

314Background: Poly(ADP-ribose) polymerases (PARP) are activated by DNA strand breaks and important for DNA repair in response to platinum-based chemotherapy. PARP inhibition with Vel might enhance anti-tumor effects of Cap with Ox. This phase I study (NCI 8604) examines the tolerability, safety and preliminary efficacy of the combination of Vel with Cap and Ox. Methods: This is a phase I dose escalation protocol testing escalating doses of Vel with Cap and Ox every 28 days (Table 1). Pts were treated in cohorts of 3-6 pts until cycle 1 DLTs were defined. Key eligibility criteria included age ≥ 18 with histologically confirmed malignancy meeting at least one of the following: documented BRCA1/2 mutation and a BRCA related malignancy; a 20% probability of harboring a BRCA mutation; metastatic colorectal cancer; mucinous ovarian cancer; other GI malignancy in which Ox has demonstrated activity. Results: 17 pts (median age 52 [range 19-71]; 14 female, 3 male) were treated at 4 dose levels (DL) (Table 1). Pts...