Evidence & research
Surrogate endpoint
Also known as: biomarker endpoint
A measurable proxy — a blood marker, a scan — used to stand in for the outcome anyone actually cares about.
In plain terms
Surrogates are convenient and sometimes wrong. A compound can raise IGF-1, increase lipolysis, or improve a marker of inflammation without improving any outcome a person would notice. Ask what was measured, then ask whether that is the thing you want.
Guides that use this term
CJC-1295, ipamorelin and MK-677 reliably raise growth hormone and IGF-1 in humans. What the trials have not shown is that raising those numbers produces the outcomes people take them for.
A 2026 meta-analysis found lean mass falls in absolute terms on GLP-1 drugs while rising as a proportion of body weight. Both statements are true, and they explain the entire argument.
Educational reference only. Pepperz does not provide medical advice, diagnosis, treatment, prescribing guidance, or dosing recommendations.