SAB Biotherapeutics (SABS) Corporate presentation summary

Clinical efficacy and safety results

• SAB-142, a fully human anti-thymocyte globulin, demonstrated early efficacy signals in type 1 diabetes (T1D) patients, including C-peptide preservation and improved glycemic control, with 4 of 4 treated patients showing C-peptide preservation and 3 of 4 showing enhancement over 120 days.

• Exogenous insulin use decreased and time in range (TIR) improved from 73% to 85% by end of study in the SAB-142 group.

• No severe adverse events, serum sickness, or anti-drug antibodies (ADA) were detected following repeat administration, supporting a favorable safety profile.

• No lymphodepletion, neutropenia, thrombocytopenia, or significant changes in white or red blood cell counts were observed on single or repeat dosing.

• Only mild cytokine release syndrome (CRS) was reported.

Pharmacodynamics and mechanism of action

• SAB-142 preserves regulatory T cells (Tregs) and enhances T cell exhaustion markers (PD-1+, TIGIT+), which are associated with improved clinical outcomes.

• The drug binds to multiple T cell surface proteins (CD2, CD3, CD4, CD8), similar to rabbit ATG, but without causing sustained lymphodepletion.

• Transient lymphopenia due to margination was observed, with lymphocyte counts returning to baseline within 5 days.

• Increased T cell exhaustion profile correlated with better efficacy, especially in super responders.

• SAB-142’s multi-specific mechanism enables sustained immunomodulation and immune tolerance restoration.

Pharmacokinetics and immunogenicity

• SAB-142 exhibits dose-dependent and predictable pharmacokinetics (PK) on both induction and maintenance dosing.

• Low immunogenicity was confirmed on single and repeat dosing, enabling safe and reliable redosing.

• No anti-drug antibodies were detected through Day 360 in redosing cohorts.