A Dose Escalation and Expansion Trial With BYON4228 Alone and in Combination in Patients With Advanced or Metastatic Solid Tumors

A Dose Escalation and Expansion Trial With the SIRPα-directed Monoclonal Antibody BYON4228 Alone and in Combination to Evaluate the Safety, Pharmacokinetics, Pharmacodynamics and Efficacy in Patients With Advanced or Metastatic Solid Tumors

Status

Active, not recruiting

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT06932952

Enrollment

Registered

2025-04-17

Start date

2025-05-07

Completion date

2026-12-01

Last updated

2026-01-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Solid Tumor

Keywords

mAB, Monoclonal antibody, SIRPα, CD47, SIRP

Brief summary

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.

Detailed description

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.

Interventions

DRUGBYON4228 + 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.

Study design

Allocation

Intervention model

SEQUENTIAL

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Patient with histologically confirmed, locally advanced or metastatic cancer who has progressed on standard therapy or for whom no standard therapy exists: * Part 1 (dose escalation): Solid tumors of any origin; * Part 2 (expansion): Patients with other solid tumor types indicated for pembrolizumab monotherapy; * Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1; * For Part 2 only: at least one measurable cancer lesion as defined by the Response Evaluation Criteria for Solid Tumors (RECIST version 1.1); * Adequate baseline organ function.

Exclusion criteria

* Having been treated with CD47 or SIRPα targeting agents or other anticancer therapy within 4 weeks prior to the start of IMP treatment; * History of hypersensitivity or allergic reaction to any of the excipients of BYON4228; * Any contraindication to pembrolizumab treatment; * For Part 2: Patients previously given a PD-1 or PD-L1 inhibitor who had subsequent disease progression within 8 weeks of initiation; * Symptomatic brain metastases; * History of autoimmune disorders; * Severe active infection or other severe uncontrolled systemic disease; * Having clinically significant cardiovascular disease; * Known infection of Hepatitis B, C or E. Key inclusion and

Design outcomes

Primary

Measure	Time frame	Description
Incidence of Dose-Limiting Toxicities	21 days	—
Objective Response Rate	2 years	Part 2 (expansion): To evaluate the objective tumor response rate (ORR).

Countries

Belgium, Spain, United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026