SV-BR-1-GM + cyclophosphamide + interferon + retifanlimab

This is a **combination therapy regimen** that includes the following components: \n- **SV-BR-1-GM**: A genetically engineered, irradiated, allogeneic breast cancer cell line that overexpresses granulocyte-macrophage colony-stimulating factor (GM-CSF), used as a **whole-cell cancer vaccine** to stimulate tumor-specific immune responses in breast cancer. SV-BR-1-GM expresses HLA class I and II, a variety of tumor-associated antigens, and genes supportive of antigen presentation and immune activation. \n- **Cyclophosphamide**: An alkylating **chemotherapeutic**, administered at low dose before SV-BR-1-GM, used for transient immune modulation, particularly to suppress regulatory T cells and improve vaccine efficacy. \n- **Interferon**: Specifically interferon-alpha 2b, administered intradermally into inoculation sites after SV-BR-1-GM (timed for additional immune stimulation; acts as a "danger signal" enhancing dendritic cell activity and antigen presentation). \n- **Retifanlimab**: A humanized **monoclonal antibody** that targets programmed death-1 (PD-1), functioning as an **immune checkpoint inhibitor** to override T-cell exhaustion and augment antitumor immunity.\n\nThe regimen is being studied in **breast cancer (advanced/metastatic)**, particularly to maximize immune system activation and object tumor regression via multi-pronged immunologic mechanisms. Retifanlimab is being incorporated to improve the efficacy of SV-BR-1-GM by blocking immune checkpoints[3][4][5]. \nSV-BR-1-GM and this regimen are developed primarily by BriaCell Therapeutics.