OSE Immunotherapeutics SA announced acceptance of an upcoming poster presentation at the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting, being held June 4 – 8, 2021, covering promising initial data from Phase 1 dose escalation of selective SIRPa inhibitor BI 765063 in patients with advanced solid tumors (Abstract #2623). The data to be presented at ASCO 2021 indicate that OSE Immunotherapeutics’ first-in-class signal regulatory protein a (SIRPa) inhibitor BI 765063 was well-tolerated, showed sustained receptor occupancy (RO) saturation and monotherapy activity. Clinical benefit was observed in 45% of patients evaluable per RECIST* criteria. A durable partial response was observed in an advanced hepatocellular carcinoma (HCC) patient, and the on-treatment biopsy of the responder showed an increase in CD8 T-cell infiltration and activation. Furthermore, the on-treatment biopsy also showed an increase in PD-L1 expression on tumor cells. A BI 765063 dose escalation study in combination with Ezabenlimab (PD-1 antagonist) is ongoing and will help determine the recommended dose for further Phase 2 clinical development in patients with advanced solid tumors.