Intraperitoneal treatment with the trifunctional bispecific antibody Catumaxomab in patients with platinum-resistant epithelial ovarian cancer: A phase IIa study of the AGO Study Group

ObjectiveThe aim of this study was to select the best catumaxomab regimen for further investigation in ovarian cancer based on confirmed tumour response.MethodsRandomised open-label phase IIa study in women with platinum-resistant or -refractory epithelial ovarian cancer. Catumaxomab (6-hour intraperitoneal infusion on days 0, 3, 7 and 10) was administered at a low (10, 10, 10 and 10 μg) or high dose (10, 20, 50 and 100 μg). Responders were patients with either a complete (CR) or partial (PR) response.ResultsForty-five patients were randomised to receive either low dose (23) or high dose (22). There were no responders in the low-dose versus one patient (5%) in the high-dose group with a PR. In the low-dose group, two patients (9%) had stable disease compared with five patients (23%) in the high-dose group. Catumaxomab was well tolerated and there was no difference between the dose groups in the incidence of treatment-induced adverse events, the most common of which were gastrointestinal and injection-site reactions.ConclusionCatumaxomab had modest activity in platinum-resistant ovarian cancer. The high-dose regimen was associated with a slightly better therapeutic index than the low dose regimen.

Research highlights
► Catumaxomab is a trifunctional antibody specifically binding to EpCAM+ epithelial cancer cells, and to ovarian cancer cells alike.
► This phase II study investigated the effects of catumaxomab on platinum-resistant ovarian cancer.
► Catumaxomab has modest growth inhibitory effects on platinum-resistant ovarian cancer.