FDA Grants Fast Track Designation to IO-202 for R/R AML

IO-202, a LILRB4 checkpoint inhibitor, has been granted a fast track designation by the FDA for the treatment of patients with relapsed or refractory acute myeloid leukemia (AML), according to a press release from Immune-Onc Therapeutics.¹

The purpose of the designation is to facilitate development and hasten review of drugs for the treatment of serious diseases and to fulfil unmet needs. Based on the designation, IO-202 will be could eligible for more interactions and communications with the FDA with regard to the agent's development plan and data collection to support a future approval, as well as accelerated approval and priority review.

“We are pleased that the FDA has granted IO-202 fast track designation in recognition of its potential to improve outcomes for people with relapsed or refractory AML. We look forward to working closely with the FDA to accelerate the clinical development of IO-202, which is currently being evaluated as a monotherapy and in combination with other agents in a phase 1 dose escalation and expansion trial in patients with AML with monocytic differentiation and in chronic myelomonocytic leukemia (CMML),” Paul Woodard, PhD, chief medical officer of Immune-Onc, said in a press release.

Preclinical findings have shown that IO-202 converts “don’t kill me” signals to “kill me” signals by activating T-cell killing and converts “don’t find me” signals to “find me” signals by inhibiting blood cancer cell infiltration. LILRB4 is a protein found of monocytic cells and inhibits antigen-presenting cell activation, thus generating immune tolerance. IO-202 was previously granted orphan drug designation in November 2020.²

A open-label, non-randomized, dose-escalation and expansion study phase 1 clinical trial (NCT04372433) assessing the use of single-agent IO-202 in patients with AML and CMML is currently open for enrollment. The study’s estimated enrollment is 44 patients. In the dose escalation phase, patients will receive IO-202 intravenously in ascending doses every 2 weeks, and those in the dose expansion will receive IO-202 intravenously at the recommended phase 2 dose.

Primary end points for the study include safety measured by the number of adverse effects (AEs), safety measured by severity of AEs, and tolerability measured by incidence and duration of dose interruptions and dose reductions during treatment. Secondary end points include pharmacokinetics, evaluation of anti-drug antibodies against IO-202, and rates of response to IO-202 in those with anti-drug antibodies.

Patients were eligible for treatment if they were 18 or older. Part 1 eligibility criteria for the dose-escalation portion included relapsed or refractory AML with myelomonocytic or monoblastic/monocytic differentiation and relapsed or refractory CMML who progressed with available therapies for active disease.

During the expansion phase, patients must have relapsed or refractory AML with myelomonocytic or monoblastic differentiation and has progressed while on treatment with other available therapies therapies. Other inclusion criteria included patients having serial bone metastasis aspirates or biopsies as well as peripheral blood sampling, an ECOG status of 0 to 2, and adequate hepatic and renal function.

Immune-Onc has also received investigational new drug clearance in January 2022 for IO-202 in solid tumors.

References

1. Immune-Once Therapeutics received FDA fast track designation for IO-202, the first-anti-LILRB4 myeloid checkpoint inhibitor, for the treatment of relapsed or refractory acute myeloid leukemia (AML). News Release. Immune-Onc. February 17, 2022. Accessed February 18, 2022. https://bit.ly/3v0MUIP

2. Immune-Onc Theraputics announces orphan drug designation of IO-202 (anti-LILRB4) for treatment of AML and poster presentation at ASH 2020. News Release. Immune-Onc. November 10, 2020. Accessed February 18, 2022. https://bit.ly/3uYPOxT