Biomarker

A biomarker (biological marker) is a defined, objectively measurable characteristic that serves as an indicator of normal biological processes, pathogenic states, or pharmacological responses to an intervention. Biomarkers are classified by function: diagnostic biomarkers identify disease, prognostic biomarkers predict outcome, predictive biomarkers indicate likely response to treatment, and pharmacodynamic biomarkers confirm that a compound is having its intended biological effect. In peptide research, commonly monitored biomarkers include serum IGF-1 levels for growth hormone secretagogues like CJC-1295 and Ipamorelin, HbA1c and fasting glucose for metabolic peptides like tirzepatide, inflammatory cytokine panels for recovery peptides like BPC-157, and telomere length for anti-ageing peptides like Epithalon. The validation of reliable biomarkers is critical for translating preclinical peptide findings into clinical applications, as they provide objective endpoints that complement subjective outcome measures in clinical trials.