Anaptysbio, Inc. · NASDAQ:ANAB
Anaptysbio — Technical Presentation (2025)
11 slides from Anaptysbio's technical presentation, 2025
Slide 1: Rosnilimab, a Depleter and Agonist Antibody Targeting PD-1+ T Cells, in Clinical Development for UC
651 Rosnilimab, a Depleter and Agonist Antibody Targeting PD-1+ T Cells, in Clinical Development for Ulcerative Colitis, Reduces Pathogenic PD-1+ T Cells and Inflammatory Cytokine Secretion in Patient Blood and in a Mouse Model of Colitis Pejman Soroosh, Stephen Parmley, Chris Haines, Richard T. Fra
Slide 2: Dysregulation of PD-1 Signaling Impacts Critical T Cell Responses in Inflammatory Diseases such as UC
Dysregulation of Programmed Cell Death Protein (PD-1) Signaling Impacts Critical T Cell Responses in Inflammatory Diseases such as UC • PD-1 is a coinhibitory receptor expressed on activated T cells – Functions to downregulate activated T cells by inducing negative signaling when engaged with its li
Slide 3: PD-1 and its Role in Ulcerative Colitis
PD-1 and its Role in Ulcerative Colitis Elevated levels of PD-1+ inflammatory cells is associated with active UC and lower remission rates High expressing PD-1+ T cells (PD-1high) represent highly Reduction of elevated PD-1high Tph cells inflammatory cells that are elevated and dysregulated in UC1-3
Slide 4: Proposed Mechanism of Action for Rosnilimab
Proposed Mechanism of Action for Rosnilimab Modulation through PD-1 may restore immune homeostasis in numerous autoimmune and inflammatory indications, including UC Rosnilimab aims to: 1 Rapidly engage homeostatic mechanisms to induce clinical response 2 Achieve durable remission through histologic
Slide 5: Membrane Proximal Binding Rosnilimab Results in Greater Reduction of PD-1+ T Cells and IFN-γ Secretion In Vitro
Membrane Proximal Binding Rosnilimab Results in Greater Reduction of PD-1+ T Cells, T Cell Proliferation and IFN-γ Secretion In Vitro Rosnilimab Reduced T Cell Proliferation and PD-1+ T Cells PD-1 Membrane Test Article T Cell Proliferation* No. of PD-1+ T Cells* Binding Epitope Reference 1 Distal ~2
Slide 6: FcR Engagement via IgG1 Domain Results in Reduced PD-1high T cells and Cytokine Secretion in UC PBMCs
FcR Engagement via IgG1 Domain of Rosnilimab Results in Reduced PD-1high T cells and Inflammatory Cytokine Secretion in UC Patient- Derived PBMCs Rosnilimab IgG1 reduced PD-1high T PD-1high T Cell Population PD-1+ T Cell Proliferation cells and proliferating PD-1+ T cells (normalized to isotype) (no
Slide 7: Therapeutic Dosing of Rosnilimab mIgG2a Demonstrated Efficacy in a Murine Model of Colitis
Therapeutic Dosing of Rosnilimab mIgG2a Demonstrated Efficacy in a Murine Model of Colitis Study Design for hPD1 CD4+ Transfer Murine Model of Colitis Rosnilimab mIgG2a maintained body weight Rosnilimab mIgG2a reduced colonic inflammation Colitis Induction and Mouse Body Distal Colon Histology and W
Slide 8: Rosnilimab mIgG2a Significantly Reduced CD4+ T Cell Infiltration into the Colon of Mice with Colitis
Rosnilimab mIgG2a Significantly Reduced CD4+ T Cell Infiltration into the Colon of Mice with Colitis Number of CD4+ T Cells % CD4+%CD4+ T Cells of Total Cells T cells ✱✱✱✱ ✱ 40 (#CD4+/#Total cells x 100) 30 %CD4 T cells 20 10 0 Parmley, et al. Presented at the UEGW meeting, Vienna, Oct 12-15, 2024 *
Slide 9: Rosnilimab mIgG2a Significantly Reduced Gene Expression of Inflammatory Cytokines in the Colon
Rosnilimab mIgG2a Significantly Reduced Gene Expression of Inflammatory Cytokines in the Colon of Mice with Colitis Ifng Cxcl13 ✱ ✱ 8 80 Expression (CPM) Expression (CPM) 6 60 4 40 2 20 0 0 Parmley, et al. Presented at the UEGW meeting, Vienna, Oct 12-15, 2024 *p<0.05 compared to isotype mIgG2a 9
Slide 10: Rosnilimab Treatment Normalized Dysregulated Gene Signatures in Mice with Colitis
Rosnilimab Treatment Normalized Dysregulated Gene Signatures in Mice with Colitis In the murine model of colitis, treatment with rosnilimab Lymphocyte mIgG2a modulated pathway genes relevant in human UC: gene signature • Reduced lymphocyte gene signature • Reduced inflammatory myeloid cell gene sign
Slide 11: Conclusion
Conclusion • Rosnilimab reduced PD-1high T cells and inflammatory cytokine secretion in UC patient-derived PBMCs in vitro • In a murine model of colitis, at Day 49, rosnilimab mIgG2a: – Demonstrated efficacy with a therapeutic dosing regimen – Significantly reduced colonic inflammation measured by h