Immunogenicity Summary Report — GLPI-103
| Field | Value |
|---|---|
| Document ID | IMMUNO-001 |
| Version | 1.0 |
| Status | Final |
| Compound | GLPI-103 (GLP-1 / Apelin [APJ] receptor dual agonist) |
| Sponsor | Virtual Biopharma Inc. |
| CTD location | Module 5.3.3 / 2.7.2 — Immunogenicity (integrated) |
| Standard(s) | FDA "Immunogenicity Assessment", EMA immunogenicity guideline, FDA "Immunogenicity Testing" (assay); ICH S6(R1) (nonclinical) |
| Confidentiality | Confidential — portfolio use |
[MOCK — deep-knowledge assumption]No immunogenicity dataset is simulated. Findings are illustrative and consistent with an acylated synthetic peptide and with IB-001 §5, CSR-101 §6, and the nonclinical PK package (M4-2.2). This document stands in for the integrated immunogenicity assessment a real submission would file.
Change History
| Version | Date | Author | Summary of Change |
|---|---|---|---|
| 1.0 | 2026-07-05 | Clinical Pharmacology / Bioanalytical | Initial submission-grade integrated immunogenicity summary |
Abbreviations
ADA anti-drug antibody · NAb neutralizing antibody · TE-ADA treatment-emergent ADA · PK pharmacokinetics · PD pharmacodynamics.
1. Background and Risk Assessment
GLPI-103 is a synthetic peptide incorporating fatty-acid acylation and non-natural residues. As a low-molecular-weight, non-glycosylated peptide of largely non-endogenous sequence, its a-priori immunogenicity risk is low-to-moderate: the theoretical concerns are (i) anti-drug antibodies (ADA) that alter pharmacokinetics or reduce efficacy via neutralization, (ii) cross-reactivity with the endogenous incretin/apelin systems, and (iii) hypersensitivity/injection-site reactions. A risk-based, tiered testing strategy was applied across the program.
2. Immunogenicity Testing Strategy
A tiered assay approach (BIOANALYTICAL-001) was used:
| Tier | Assay | Purpose |
|---|---|---|
| Screening | validated bridging immunoassay | detect binding ADA |
| Confirmatory | competitive inhibition with excess drug | confirm specificity |
| Characterization — titre | serial dilution | quantify magnitude |
| Characterization — neutralizing | competitive ligand-binding NAb assay | detect NAb |
| Cross-reactivity | endogenous GLP-1 / apelin binding | assess pathway risk |
Sampling followed a risk-based schedule (baseline, on-treatment, and end-of-treatment/follow-up), with drug-tolerance and cut-point determination per the assay validation.
3. Immunogenicity Findings Across the Program [MOCK]
| Study | Population / exposure | ADA incidence (treatment-emergent) | Neutralizing | PK/PD/safety impact |
|---|---|---|---|---|
| GLPI103-101 (SAD) | single dose, healthy | low | none | none |
| GLPI103-102 (MAD) | multiple dose | low | none | none |
| GLPI103-201 (Phase 2) | 24 weeks | low, transient | none/rare | none |
| GLPI103-301 (Phase 3) | 52 weeks | low, mostly transient, low-titre | non-neutralizing | no effect on exposure, HbA1c response, or safety |
Across the program, treatment-emergent ADA were infrequent, low-titre, transient, and non-neutralizing. In the population-PK covariate analysis, ADA status had no clinically relevant effect on GLPI-103 clearance (CLINPHARM-002 §3), and no attenuation of the HbA1c response was seen in ADA-positive subjects. No cross-reactivity with endogenous GLP-1 or apelin was detected. Injection-site reactions (IV formulation) were mild and did not correlate with ADA status.
4. Clinical Consequences and Conclusion
The immunogenicity profile of GLPI-103 is favourable and consistent with the synthetic-peptide class: low-incidence, low-titre, transient, non-neutralizing binding antibodies without measurable impact on pharmacokinetics, efficacy, or safety, and without cross-reactivity to endogenous ligands. No immunogenicity-related risk minimization is required beyond routine pharmacovigilance. These conclusions are integrated in Module 2.7.2 (Clinical Pharmacology) and the Clinical Safety Summary (M2.7.4), and are reflected in the Risk Management Plans (RMP-EU/US/KR) as routine monitoring.
5. References
IB-001 §4.2, §5; CSR-101 §6; CLINPHARM-002 (population PK); BIOANALYTICAL-001 (assay validation); M2.7.2; M2.7.4; M4-2.2; FDA/EMA immunogenicity guidance; ICH S6(R1).