Outpatient therapy of malignant ascites related to advanced gynecologic carcinomas with intraperitoneal application of the trifunctional antibody catumaxomab

Objectives: Catumaxomab (CATU) is a trifunctional antibody approved for the treatment (Tx) of malignant ascites (MA) related to EpCAM-positive tumors. CATU is mostly administered in a hospital. We report on our single-institution experience with outpatient CATU in patients (pts) with MA due to various gynecologic carcinomas.

Methods: 26 patients were included: epithelial ovarian cancer (14), metastatic breast cancer (6), endometrial cancer (3), other (3). Patients had failed a median of 4 prior systemic Tx (range: 1 – 12). CATU was administered at four planned increasing doses (i.e., 10, 20, 50, and 150 µg) given at 4-day intervals over 2 weeks. Toxicities were scored according to the CTCAE 4.0 scale. Puncture-free survival (PuFS) was calculated from start of CATU to the next puncture, death, or loss to follow-up. Overall survival (OS) was calculated from start of CATU to death or loss to follow-up.

Results: All pts received CATU in an outpatient setting with 17 pts (65.4%) receiving all four planned applications. CATU was generally well tolerated. Secondary hospitalization was necessary in 7 pts: fever, n = 1; abdominal pain, n = 1; generally deteriorated condition, n = 5.. Subsequent punctures were necessary in 5 pts (19.2%). Median PuFS was 79.5 days, median OS was 93.5 days. 11 pts (42.3%) received systemic Tx after IP CATU. 5 pts are still alive and free from subsequent punctures after a maximum of 876+ days.

Conclusions: Outpatient IP CATU treatment of MA due advanced gynecologic malignancies is feasible and efficacious. Moreover, CATU allows for subsequent antineoplastic Tx in a substantial proportion of pts.