First-in-Human Study of XMT-1536 in Cancers Likely to Express NaPi2b

This is a multi-center study of XMT-1536 (upifitamab rilsodotin) in patients with tumors likely to express NaPi2b, focusing on patients with platinum-resistant ovarian cancer and non-small cell lung cancer, adenocarcinoma subtype. XMT-1536 (upifitamab rilsodotin) was administered as an intravenous infusion once every four weeks. The study consisted of three segments: dose escalation (DES), dose expansion (EXP), and the pivotal cohort (UPLIFT). The DES segment studied small groups of patients who received increased doses. A Safety Review Committee was established to review the data from each dose level before moving to the next higher dose. The dose escalation cohort has ended and is no longer enrolling patients. Enrollment into the EXP segment consisted of 2 parallel cohorts of patients to confirm the dose that has been identified in DES and estimate the objective response rate in each patient population. The EXP and UPLIFT cohorts are no longer enrolling patients. All adverse events were graded according to the National Cancer Institute (NCI) Common Terminology Criteria version (CTCAE v5.0). Throughout the study, pharmacokinetics were measured using proprietary assays developed by Mersana. Anti-cancer activity were measured via RECIST.