FDA clears IO-202, a novel LILRB4 antibody, for investigation as a new drug in AML

On May 29, 2020, the United States Food & Drug Administration (FDA) cleared IO-202, an antibody targeting leukocyte immunoglobulin-like receptor B4 (LILRB4), for investigation as a new drug treatment for acute myeloid leukemia (AML) in patients with monocytic differentiation and chronic myelomonocytic leukemia (CMML).¹

Key features¹

IO-202:

• A first-in-class monoclonal antibody that blocks the signaling of LILRB4, an immune inhibitory receptor
• The first T cell activator for AML
• Known to activate T cell cytotoxicity against leukemia cells in preclinical studies and block tumor infiltration

Study Design^1,2

• Phase I, multicenter, open-label, dose-escalation and dose expansion study, to determine the optimal dose of IO-202 in adult patients with AML with monocytic differentiation and in those with CMML
• Will assess IO-202 as a monotherapy or in combination with azacitidine
  • For the dose escalation phase, dose cohorts will be treated with intravenous (IV) IO-202 monotherapy, in ascending doses every 2 weeks, followed by IO-202 every 2 weeks at the same dose in combination with IV or subcutaneous azacitidine, 75 mg/m² for 7 days every 28 days
  • For the expansion phase, IV IO-202 monotherapy will be given at the recommended phase II dose and frequency; combination therapy will consist of IV IO-202 every 2 weeks at the recommended phase II dose and frequency with IV or subcutaneous azacitidine, 75 mg/m² for 7 days every 28 days
• Primary outcomes will evaluate the safety and tolerability of IO-202
• Secondary outcomes will evaluate pharmacokinetics, pharmacodynamics, and clinical activity of IO-202

Biomarkers assessment will also enable a mechanistic understanding of the clinical data and inform future trials.