Clinical Hold on XMT-2056 Phase 1 Clinical Trial

CAR-T Digest - August 2020

13 Mar 2023: XMT-2056 (IV) / Solid Tumors / Mersana Therapeutics: Announced a clinical hold on its STING agonist ADC in Phase 1 trial

Mersana Therapeutics announced a clinical hold on its Phase 1 clinical trial of XMT-2056
XMT-2056 is an Immunosynthen STING agonist ADC (DAR 8) created to target a new HER2 epitope and locally activates STING signaling in tumor-resident immune cells as well as in tumor cells
- The hold is due to a recent Grade 5 (fatal) serious adverse event associated with XMT-2056 recorded in a patient enrolled in the Phase 1 FIH dose escalation & expansion study evaluating the safety and side effects of XMT-1600 for solid tumors
In May 2022, the US FDA designated XMT-2056 as an orphan medication for the treatment of stomach cancer
“In line with our steadfast commitment to patient safety, we have been proactive in our response to this event. With the clinical hold in place, our efforts for XMT-2056 are now focused on undertaking the work required to fully analyze this SAE and consider potential next steps for development,” said Anna Protopapas, President and CEO of Mersana Therapeutics