Anti-Ley Monoclonal Antibody (Mab) Hu3s193 As Consolidation Therapy For Patients (Pts) With Relapsing Platinum Sensitive Ovarian Cancer (Oc) After Achieving A Second Complete Response (2cr).

e17039Background: Lewis-Y (LeY) antigen is a blood group related antigen expressed in 75% of OC. hu3S193 is a humanized anti-LeY IgG1 mAb with strong complement and antibody dependent cytotoxicity with clinical benefit shown in a phase II study in pts with platinum-resistant OC and small tumor burden. Improving progression free survival (PFS) in pts who achieve a 2CR is an unmet need. Methods: This phase II study accrued pts with relapsed OC, LeY expression by IHC, and a KPS ≥ 70% who had achieved a 2CR after 5-8 cycles of platinum doublet chemotherapy (chemoRx). Patients received intravenous infusions of hu3S193, 30mg/m2every 2 weeks starting ≤ 8 weeks after the last dose of chemoRx and continuing for 12 doses (24 weeks) or until disease progression or unacceptable toxicity. Primary endpoint was PFS with a sample size calculated to detect a 50% increase in PFS, compared to a historical value of 10.8 months. Secondary objectives were safety and pharmacokinetics (PK). Results: 29 pts were enrolled. Median ...