OncoResponse, a US-based clinical-stage biotech company advancing immunotherapies derived from the immune systems of Elite Cancer Responders, announced on Wednesday that it has started dosing the first subject in the Phase one/two trial of OR502, a novel, humanised anti-leukocyte immunoglobulin like receptor B2 (LILRB2) antibody that rescues innate and adaptive immune responses from LILRB2 mediated immune suppression.

This Phase 1/2 study is an open-label, multicentre, first-in-human dose-escalation and expansion study designed to determine the safety, tolerability, and preliminary anti-tumour activity of OR502, a fully human IgG1 antibody that binds specifically to LILRB2. OR502 will be administered as a monotherapy and in combination with anti-PD-1, cemiplimab, in subjects with advanced solid tumours. The study consists of two parts. Part A is a dose-escalation phase to determine the maximum-tolerated dose (MTD) or optimal dose of OR502 for further evaluation as monotherapy and in combination. Part B is an expansion phase in subjects with advanced solid tumours treated with OR502 at two separate doses, to help determine the recommended Phase 2 dose (RP2D) for further development and determine preliminary anti-tumour activity.

The role of potential biomarkers will be evaluated throughout the study, and more intensively in a separate biology cohort. Additional details are available on ClinicalTrials.gov, identifier: NCT06090266.

Clifford Stocks, chief executive officer of OncoResponse, said, 'Initiating this study in cancer patients reflects our continued commitment to advancing programs that have the greatest potential to improve outcomes for patients undergoing cancer treatment.'