A Phase 1 interventional study of BYON4228 + Pembrolizumab in Solid Tumor, sponsored by Byondis B.V.. Active, not recruiting at 6 sites in 3 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-01-16.
Sponsored by Byondis B.V. · Phase 1, Interventional, and Treatment
This is a phase I trial with BYON4228, a humanized monoclonal antibody (mAb) directed against signal regulatory protein (SIRP)α in solid tumors, alone and in combination with pembrolizumab.
This study includes a dose escalation part (Part 1) in which the MTD or OBD and RDE(s) will be determined. This trial includes an expansion part (Part 2) to evaluate efficacy and safety of BYON4228 in combination with pembrolizumab in specific patient cohorts.
BYON4228 is a humanized IgG1 mAb directed against SIRPα. BYON4228 binds SIRPα expressed on innate immune cells, especially monocytes, macrophages and neutrophils. BYON4228 blocks binding of SIRPα to CD47 and inhibits signaling through the CD47-SIRPα axis.
Patient with histologically confirmed, locally advanced or metastatic cancer who has progressed on standard therapy or for whom no standard therapy exists:
Exclusion Criteria:
Key inclusion and exclusion criteria details are listed here, additional requirements may apply.
Drug: BYON4228 + Pembrolizumab
BYON4228 is a humanized monoclonal antibody (mAb) directed against SIRPα. BYON4228 IV infusion every three weeks until disease progression or unacceptable toxicity. Different doses. Pembrolizumab IV infusion (200 mg) every three weeks from the second treatment cycle onwards.
Incidence of Dose-Limiting Toxicities
Time frame: 21 days
Objective Response Rate
Part 2 (expansion): To evaluate the objective tumor response rate (ORR).
Time frame: 2 years
This study is active, not recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Byondis B.V.