Mersana Therapeutics, Inc., a clinical-stage biopharmaceutical company, develops antibody-drug conjugates (ADC) for cancer patients with unmet needs. The company develops Emi-Le (XMT-1660), a B7-H4-targeting Dolasynthen ADC candidate, which is in Phase 1 clinical trial; and XMT-2056, an Immunosynthen ADC targeting a novel human epidermal growth factor receptor 2 that is in Phase 1 clinical trial. Its preclinical products portfolio includes XMT-2068 and XMT-2175. It has strategic research and development collaborations with Janssen Biotech, Inc., Ares Trading S.A., Merck KGaA, and Asana Biosciences, LLC for the development of ADC product candidates.