A phase I study of EpCAM/CD3-bispecific antibody (MT110) in patients with advanced solid tumors.

2504 Background: MT110 is a bispecific T cell engaging antibody construct (BiTE) that directs CD3 expressing T cells to kill target cells that express EpCAM, which is widely found on solid tumors. Methods: Safety, tolerability, pharmacokinetics and anti-tumor activity of MT110 in patients (pts) with advanced solid tumors were studied using a 3+3 design. Continuous IV infusions for at least 28 days of doses ranging from 1 to 48 µg/d have been tested. Stepwise intra-patient dose escalations within cycle 1 or at start of cycle 2 have been explored. Results: 51 pts (6 gastric cancers, 32 CRC, 2 SCLC, 5 NSCLC, 3 HRPC, 1 ovarian cancer) have been treated in 12 dose cohorts. The maximally administered dose includes day 1 dose of 3 µg/d escalated up to 48 µg/d. The maximum tolerable dose (MTD) has not yet been established. Diarrhea and elevations in liver function tests have been reported as dose limiting toxicity (DLT) for individual patients. Transaminase elevations were fully reversible and mitigated by dexame...