Approximately 50 patients will be randomized 1:1 to one of two dose/schedule cohorts: one with a continuous dosing schedule (100 mg QD) and one with an induction dosing schedule (120 mg QD x 14 days, then 80 mg QD starting Day 15). Patients will receive treatment with mivavotinib until disease progression, unacceptable toxicity, withdrawal of consent, or death.
Study CX-659-401 is a multicenter, open-label, phase 2 study of mivavotinib to evaluate the single-agent activity of mivavotinib in patients with relapsed/refractory non-GCB/ABC DLBCL, incorporating ctDNA-based next-generation sequencing (NGS) to identify DLBCL patients harboring MyD88 and/or CD79B mutations within the study. This goal of this strategy is to evaluate its activity both in the cell-of-origin subgroup of non-GCB/ABC DLBCL and in the genetically defined subgroups of MyD88/CD79B-mutated and wild type DLBCL.