NCT07115667

Radiation Combined With BCMA/CD3 Bispecific Antibody Therapy for Solitary Bone Plasmacytoma With Mild Bone Marrow Infiltration

A Prospective Single-Arm Clinical Trial of Radiation Combined With BCMA/CD3 Bispecific Antibody Therapy for Solitary Bone Plasmacytoma With Mild Bone Marrow Infiltration

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 21 (estimated)
• Sponsor: Institute of Hematology & Blood Diseases Hospital, China · Academic / Other
• Sex: All
• Age: 18 Years – 78 Years
• Healthy volunteers: Not accepted

Summary

This is a prospective, single-arm, single-center clinical trial designed to evaluate the safety and efficacy of radiation combined with a BCMA/CD3 bispecific antibody (CM336) in patients with solitary bone plasmacytoma (SBP) with mild bone marrow infiltration.

Detailed description

This is a prospective, single-arm, single-center clinical trial designed to evaluate the safety and efficacy of radiation combined with a BCMA/CD3 bispecific antibody (CM336) in patients with solitary bone plasmacytoma (SBP) with mild bone marrow infiltration. SBP is a rare plasma cell malignancy with a high risk of progression to multiple myeloma (MM), particularly in patients with minimal bone marrow involvement. Although radiotherapy is the standard treatment, it is often insufficient to eradicate clonal plasma cells and prevent progression in high-risk patients. CM336, a novel BCMA/CD3 bispecific antibody, has demonstrated promising activity in relapsed/refractory multiple myeloma. In this trial, eligible patients will receive radiotherapy followed by a 12-cycle limited treatment course of CM336, aiming to achieve deep clearance of residual malignant cells and reduce progression risk.

Conditions

• Solitary Bone Plasmacytoma
• Plasmacytoma of Bone
• Plasma Cell Disorders

Interventions

Type	Name	Description
DRUG	BCMA/CD3 bispecific antibody (CM336)	Patients with solitary bone plasmacytoma (SBP) with mild bone marrow infiltration will receive radiation combined with a BCMA/CD3 bispecific antibody (CM336)

Timeline

• Start date: 2025-08-25
• Primary completion: 2026-12-01
• Completion: 2027-12-01
• First posted: 2025-08-11
• Last updated: 2025-09-08

Locations

1 site across 1 country: China