Long game · part of Ageing and longevity
Does it change a biological age clock?
A clock is a prediction, not an outcome. Moving one has never been shown to change what happens to a person, and that limitation belongs on the result.
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people in trials
3
studies in people
2
compounds, animal or lab only
2
compounds people report on
0
trials found nothing
Measured in people
A trial that gave people the compound comes first. A study that only watched people, who happened to have more or less of something related, comes after. Both are studies in people and both are here. Only the first kind tested the thing you are asking about, and the watch-only ones are labelled. Within that, the most people come first. That is a fact about the studies, not a judgement about the compound. Counts are never added up across compounds, because the same person can be in more than one trial.
Other compounds
2 compounds · 27 people given one of themApproved drugs, biologics and hormones that have been measured for this. They are here because leaving them out would misrepresent the evidence, and they are below the peptides because that is not what most people come here to read.
- 01DanazolHormoneLimited. People have taken it in a published study, but fewer than 100 of them. 3 completed trials, 63 people given it.5 reported27 people given it1 trial, 1 watch-only
Danazol stopped telomeres shrinking, and the trial was halted early because it appeared to be working. 27 patients with inherited telomere disease took 800 mg a day by mouth, planned for two years. Everyone got the drug and there was nothing to compare against. Telomere loss slowed in all 12 patients assessable on the main measure, and 12 of the 27 met it. 11 of those 12 gained length by two years, averaging 386 base pairs. Liver enzymes rose mildly in 41 percent and a third got muscle cramps.
The numbers The result that makes danazol interesting. Phase 1 to 2 prospective study, 27 patients with inherited telomere diseases, danazol 800 mg a day orally for a planned 24 months, primary efficacy endpoint a 20 percent reduction in annual telomere attrition. Halted early because attrition was reduced in all 12 patients evaluable for the primary endpoint; 12 of 27 (44 percent) met it in intention to treat. 11 of 12 (92 percent) gained telomere length at 24 months against baseline, mean increase 386 base pairs. Haematological response in 19 of 24 evaluable at 3 months and 10 of 12 at 24 months. Grade 2 or lower elevated liver enzymes in 41 percent and muscle cramps in 33 percent.
New England Journal of Medicine, 2016· 27 people
A serious side effect surfaced years after the trial was over. Doctors at the Mayo Clinic describe pancreatitis, an inflamed pancreas, in people taking danazol for telomere biology disorders. It was published eight years after the original trial. This came out of ordinary clinical use, not from a study set up to count side effects. Nobody can tell from a report like this how often it happens.
The numbers A Mayo Clinic report describing pancreatitis in the setting of danazol therapy for telomere biology disorders, published eight years after the original trial. An adverse effect identified in ongoing clinical use rather than in the trial.
Mayo Clinic Proceedings, 2024· number of people not givenobserved only, nobody was given it
What people using it report
- Longevity forums talk about it almost only because of the 2016 telomere result. They usually leave out how many people were in it, the early stop, and the disease those people had.
- 02GDF15BiologicModerate. At least one finished study in people, and at least 100 people who took it. 2 completed trials, 313 people given it.3 reportednobody was given it1 watch-only study
Higher GDF15 marked out men who died sooner, but nobody was given anything. 876 Swedish men aged 35 to 80 gave a blood sample and were then followed for up to 14 years. Those with more GDF15 at the start were roughly three times as likely to die of any cause. The pattern held in a separate set of 324 twins. This is a group watched over time, not a trial. It cannot tell you whether lowering GDF15 would help anyone.
The numbers 876 Swedish men aged 35 to 80 followed up to 14 years: serum GDF15 at entry predicted all-cause mortality with an adjusted odds ratio of 3.38 (95 percent CI 1.38 to 8.26), validated in 324 same-sex twins and independent of telomere length, IL-6 and CRP. An association in a cohort, not an intervention.
Aging Cell, 2010· 876 peopleobserved only, nobody was given it
What people using these actually report
These are people describing their own use. They come from clinic write-ups, complaint records kept by regulators, and public forums, and they are shown as written. They are the best guide on this page to what people actually do, what they expect, and what goes wrong. They cannot show that anything works. Nobody was compared with people on a dummy pill, and people who saw no effect mostly stopped posting. Both things are true at once. The bad reports are kept in for the same reason.
- Longevity forums talk about it almost only because of the 2016 telomere result. They usually leave out how many people were in it, the early stop, and the disease those people had.
Sources: Longevity forums and patient communities in aplastic anaemia and telomere biology disorders. Uncontrolled self-report, and the patient communities are describing a different population from the people considering it for ageing.
- Many users say they felt nothing at all. Long-running longevity forum threads keep asking the same question for years without an answer. Has anyone gotten a result they could measure? And what would a longer telomere even feel like?
- The telomere and biological-age numbers people post are the weakest part. One person's months-long self-test used a saliva DNA test of biological age, not a telomere test at all. The only telomere test they could find cost about 290 dollars and needed a blood draw and a doctor. Others in the thread argued the biological-age result was not believable. Home telomere and biological-age tests are so rough that their error covers the whole claimed effect. Almost none of these reports include a starting test on the same kit.
Sources: LongeCity 'Telomeres' forum threads on Epitalon and Epithalon; the Age Reversal Forum self-experimentation thread on Epitalon (AEDG); SelfAssay's aggregated community corpus for Epitalon (258 reports, 236 contributors); vendor price tracking at peppers.market (73 vendors, retrieved August 2026). Reddit's r/Peptides is the most cited venue for this compound but was not directly readable when this section was compiled, so nothing here is drawn from it.
Measured in animals or in the lab, not yet in people
These are kept apart from the studies in people, not ranked against them. They answer a different question. A result in a rat is a real result, and a reason somebody ran the study. It is not a measure of what happens in you. When the work in people is missing, the reason is usually money, not failure. The bottom of this page explains why.
Peptides and blends
- 01EpitalonPeptideModerate. At least one finished study in people, and at least 100 people who took it. 5 completed trials, 266 people given it.6 reported1 animal or lab study
What people using it report
- Many users say they felt nothing at all. Long-running longevity forum threads keep asking the same question for years without an answer. Has anyone gotten a result they could measure? And what would a longer telomere even feel like?
- The telomere and biological-age numbers people post are the weakest part. One person's months-long self-test used a saliva DNA test of biological age, not a telomere test at all. The only telomere test they could find cost about 290 dollars and needed a blood draw and a doctor. Others in the thread argued the biological-age result was not believable. Home telomere and biological-age tests are so rough that their error covers the whole claimed effect. Almost none of these reports include a starting test on the same kit.
Measured in animals or in the lab
In a dish. The first time a lab with no link to the original group found the same direction of effect. Normal human cells grew longer telomeres, more so at higher doses. Cancer cells mostly used a different route. A November 2025 correction replaced three figures without changing the conclusions.
The numbers The first replication of the direction of the telomere effect by a group unconnected to the originators: dose-dependent telomere lengthening in normal human epithelial and fibroblast cells through hTERT and telomerase, with alternative lengthening of telomeres seen mainly in cancer lines. A November 2025 correction notice (PMID 41240216) replaced Figures 1 to 3 without changing the conclusions.
Biogerontology (Brunel University London), 2025· lab (cells in a dish)
Other compounds
- 01OSK Partial ReprogrammingBiologicPreliminary. Studied in people, but no published study has had people take it. 1 registered with no result.5 reported1 animal or lab study
Measured in animals or in the lab
In normally ageing mice, not ones bred to age fast, long stretches of partial reprogramming changed the kidney and skin. The longer the treatment ran, the bigger the change. Ageing clocks read younger. Genes for inflammation, worn-out cells and stress were turned down. The authors did not claim these mice lived longer.
The numbers Mouse, physiologically ageing wild-type rather than progeroid. Long-term partial reprogramming regimens produced duration-dependent effects in kidney and skin, with reversion of epigenetic clock measures and reduced inflammation, senescence and stress-response gene expression. The authors make no lifespan extension claim for wild-type mice.
Nature Aging, 2022· animal study
Why the trial record looks like this
A missing trial usually means nobody would pay for it. Nobody spends hundreds of millions of dollars on a molecule they cannot own. So the compounds with the thinnest record in people are often the oldest and easiest to get, not the weakest. Taking Epitalon as the example, because it states the problem most clearly:
Where Epitalon came from shapes its record. These peptides were first made inside the Soviet military medical system in the 1970s. Extracts from thymus and pineal glands were used there to restore immune function in military staff exposed to radiation and toxic chemicals. The clinical work that followed came out in Russian journals, during and after the Cold War. Western scientists mostly did not read it, list it or try to repeat it. That is a real reason nobody has repeated the work, and it has nothing to do with science. It says nothing about whether the peptide works.
Money points the same way. Epitalon is four amino acids long. Any peptide lab can make it. Price trackers list dozens of sellers at roughly 1 to 26 US dollars per milligram. Nobody can own it, so no company can earn back the cost of the careful study with a hidden dummy that would settle the question. A thin record here is partly about money. It is not proof the molecule fails.
Neither reason fixes the science problem, and that problem is real. Decades of good results from one research group, mostly in journals close to that group, with nobody else repeating them, can mean two things. It can mean a real effect nobody else bothered to test. It can also mean errors in how one group measured, chose patients or expected results. Both explanations predict the same record, so the record cannot settle it either way. The only outside support so far is in cells, not people. The 2025 Brunel study found the same direction as the 2003 telomere result. Vladimir Khavinson led the group for four decades and died in January 2024. So any proof now has to come from outside it.
A compound shows up here only when a study on its own page names this goal and reports a result for it. Just naming it is not enough. Work in people, in animals and in the lab is counted separately and never mixed. People counts come from the study lines, and when in doubt they count low. Nothing here is advice. Nothing here tells you to take or to avoid anything.