Systematically optimized BCMA/CS1 bispecific CAR-T cells robustly control heterogeneous multiple myeloma

Area of Science:

• Immunotherapy
• Oncology
• Cellular Therapy

Background:

• Chimeric antigen receptor (CAR)-T cell therapy is effective against B-cell malignancies but faces challenges with antigen escape and tumor relapse.
• Multiple myeloma (MM) remains a challenge, particularly for therapies targeting B-cell maturation antigen (BCMA) that exhibit resistance.

Purpose of the Study:

• To design and optimize bispecific CAR-T cells for treating heterogeneous multiple myeloma (MM).
• To overcome resistance to conventional CAR-T cell therapy targeting BCMA.
• To develop a robust cell-based therapy approach for novel disease targets.

Main Methods:

• Rational design and optimization of bispecific CAR-T cells targeting BCMA and CS1.
• Comparative analysis of bispecific CAR-T cells versus co-expressed individual CAR-T cells.
• In vivo efficacy studies of bispecific CAR-T cells, including combination therapy with anti-PD-1 antibody.

Main Results:

• BCMA/CS1 bispecific CAR-T cells demonstrated superior CAR expression and function compared to individual CARs.
• Combination therapy with anti-PD-1 antibody accelerated initial tumor clearance in vivo.
• CAR-T cell treatment alone resulted in durable tumor-free survival, even after tumor re-challenge.

Conclusions:

• BCMA/CS1 bispecific CAR-T cells represent a promising strategy to prevent antigen escape in MM CAR-T therapy.
• The integrated optimization process can be applied to develop advanced cell-based therapies for various diseases.
• This approach offers a potential solution for overcoming treatment resistance in multiple myeloma.