Mersana Therapeutics says FDA lifts clinical hold on Phase 1 trial of XMT-2056

Mersana Therapeutics announced that the U.S. Food and Drug Administration has lifted the clinical hold on the company’s Phase 1 clinical trial of XMT-2056. XMT-2056 is a systemically administered Immunosynthen STING-agonist ADC that is designed to target a novel human epidermal growth factor receptor 2 epitope and locally activate STING signaling in both tumor-resident immune cells and in tumor cells, providing the potential to treat patients with HER2-high or -low tumors as monotherapy and in combination with standard-of-care agents. The multicenter Phase 1 open-label trial is investigating XMT-2056 in previously treated patients with advanced/recurrent solid tumors expressing HER2, including breast, gastric, colorectal and non-small-cell lung cancers. The dose escalation and dose expansion portions of the trial will evaluate and characterize the relationship of safety, tolerability and exposure of XMT-2056 and this candidate’s preliminary anti-tumor activity, as measured by overall response rate, duration of response and disease control rate.