Methodology

Evidence tiers

Evidence is shown on a visible seven-tier scale (1 = healthy-aging human lifespan RCT, down to 7 = in vitro/mechanism) and is never collapsed into a single marketing score. Tier 1 is empty on this site by design: no telomere intervention has a healthy-aging lifespan RCT. Note the deliberate distinction between tier 2 (a human clinical-outcome RCT in a disease population, e.g. danazol or imetelstat) and a healthy-aging lifespan result — the former is real and important, but it is disease treatment, not evidence of an anti-aging effect. Tier 3 (telomere-length / telomerase-activity biomarker RCTs, e.g. TA-65) sits below that, because a biomarker change is not a clinical outcome.

Why telomere length is a contested biomarker

Telomere length is measured by several methods (qPCR, Flow-FISH, Southern/TRF) that do not always agree, varies between tissues and cell types, and associates with aging and mortality only modestly and inconsistently across cohorts. A longer measured telomere is not straightforwardly "healthier," and lengthening telomeres in a trial does not establish a slowing of human aging. Every page states this so a telomere-length result is never read as a longevity outcome.

The telomerase–cancer paradox

Telomerase is silenced in most human somatic cells and reactivated in the large majority of cancers, so pharmacologically activating it raises an unresolved cancer-risk question. The clearest illustration is that the only FDA-approved telomerase drug — imetelstat (RYTELO, 2024) — inhibits telomerase to treat lower-risk MDS. TeloiX frames imetelstat as the honesty foil: it points the opposite direction from the anti-aging "activation" narrative.

Honesty flag

Each intervention carries a flag derived by string classification of its human-evidence field: ● available is reserved for a genuine healthy-aging human lifespan RCT; ▲ qualified marks human data that is telomere-length / telomerase-activity biomarker, disease-outcome, pilot, observational, or (for imetelstat) an approved telomerase inhibitor — i.e. not a healthy-aging lifespan RCT; ○ none marks animal/preclinical-only, thin, or mechanism nodes. The classifier generalizes across the longevity cluster with zero data fabrication.

How identifiers are confirmed

Journal, volume and DOI were confirmed via Crossref; trial design and status via the ClinicalTrials.gov v2 API where an NCT was resolvable; and PMID/PMCID against Europe PMC. Each record's citation status names which source confirmed it and on what date. An identifier that cannot be confirmed is left empty and named as unconfirmed in the record, never invented and never taken from a secondary source.

This site previously used a build-time tag to mean “confirm this later”. It was removed on 2026-08-08, because a record can sit behind such a tag indefinitely while the page reads as though someone is coming back to it. The 2025 TA-65 meta-analysis was carried that way even though its own citation status recorded a confirmed DOI; it is now confirmed in full (PMID 41286474, PMCID PMC12644169). A record either names its confirmed identifiers or names what is missing and why.