The Role of CTLA-4 Pathway Inhibition in Immunotherapy


CTLA-4 pathway

Immune checkpoint pathways regulate activation of T cells at various stages of immune response.5

CTLA-4 and PD-L1 both play crucial roles in T cell regulation but have distinct differences. The CTLA-4 pathway is believed to regulate T-cell proliferation at the early stage of naive T-cell activation, principally in the lymph nodes. Activation of the CTLA-4 pathway downregulates the immune response by binding to CD80 (B7.1) or CD86 (B7.2).5

Inhibiting the CTLA-4 pathway1,6-10:

CTLA-4 is a co-inhibitory receptor CTLA-4: cytotoxic T-lymphocyte– associated antigen 4; CD80: cluster of differentiation 80; CD86: cluster of differentiation 86; CD28: cluster of differentiation 28

TAKE A DEEPER LOOKat the role of CTLA-4


Tremelimumab (anti–CTLA-4 antibody)


Tremelimumab, when used in combination with an anti–PD-L1 agent, such as durvalumab (MEDI4736), may have the potential to augment the biological and clinical effect of PD-L1 inhibition. These therapies combined may have enhanced activity compared with each one being used alone and may provide the unique benefits of immunotherapy to a broader population of cancer patients.11-13

VIEW the full list of clinical trials with tremelimumab


CTLA-4=cytotoxic T-lymphocyte–associated antigen 4; IgG2=immunoglobulin G2; mAb=monoclonal antibody; PD-L1=programmed cell death ligand-1.


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