Therapeutics

17α-Estradiol is a stereoisomer of the dominant estrogen 17β-estradiol with much weaker feminizing activity. In the NIA Interventions Testing Program, it consistently extended median lifespan in male mice, possibly via hypothalamic and metabolic effects. Mechanism is incompletely understood and human longevity data do not exist; it is not approved or established as a human anti-aging therapy.

Adeno-associated virus (AAV) gene therapy uses recombinant AAV capsids to deliver a transgene cassette — typically a promoter, coding sequence, and poly-A signal — to target tissues. Different serotypes (AAV9 for CNS/muscle, AAV8 for liver, AAV2 for retina) have distinct tissue tropisms determined by capsid-surface receptor interactions, and the ~4.7 kb packaging limit constrains which genes can be delivered as a single construct. Pre-existing NAb titres and T-cell responses to capsid proteins are the principal immunogenicity barriers, and in some trials have required plasmapheresis or high-dose immunosuppression to avoid clearance or hepatotoxicity. In longevity-relevant preclinical work, AAV vectors have been used to deliver Klotho, TERT, follistatin, and FGF21 transgenes in rodents, yielding functional improvements; no anti-aging AAV product has received regulatory approval, and all human longevity applications remain investigational or compassionate-use.

Acarbose is an alpha-glucosidase inhibitor approved for type 2 diabetes mellitus. By blocking intestinal carbohydrate breakdown, it blunts postprandial glucose and insulin spikes and shifts substrate to colonic fermentation. In the NIA Interventions Testing Program, acarbose extended median lifespan in male mice and modestly in females, an effect attributed to glycemic smoothing and microbiome shifts. Off-label longevity use in humans is investigational; gastrointestinal side effects (flatulence, diarrhea) limit tolerability.

Low-dose aspirin (typically 75–100 mg daily) is an irreversible COX-1 inhibitor that suppresses platelet thromboxane A2, reducing platelet aggregation. It is approved for secondary prevention of myocardial infarction and ischemic stroke, where benefit clearly outweighs bleeding risk. The ASPREE trial in healthy older adults showed no cardiovascular benefit, increased major bleeding, and an early signal of increased all-cause mortality (largely cancer-driven and attenuated in ASPREE-XT extended follow-up). Current guidelines discourage routine primary prevention; the USPSTF 2022 recommends individualized decision-making in adults 40–59 with at least 10 percent 10-year CVD risk and recommends against initiation in adults aged 60 or older. Cancer-prevention signals remain investigational.

Berberine is an isoquinoline alkaloid found in multiple plant genera, including Berberis, Hydrastis canadensis (goldenseal), and Coptis chinensis. It is sold as a dietary supplement in most jurisdictions and is not an approved drug in the EU or US. Berberine inhibits mitochondrial complex I, raising the AMP:ATP ratio and thereby activating AMPK downstream; small trials show modest reductions in fasting glucose, HbA1c, LDL cholesterol, and triglycerides in metabolic syndrome and type 2 diabetes. Marketed informally as natural metformin, evidence quality is limited, product purity varies, and CYP3A4-mediated drug interactions warrant caution. Longevity use is investigational.

Bisphosphonates are synthetic analogues of pyrophosphate that bind avidly to hydroxyapatite in bone mineral and are taken up by osteoclasts during bone resorption, where nitrogen-containing bisphosphonates (alendronate, zoledronate, risedronate) inhibit farnesyl diphosphate synthase in the mevalonate pathway, impairing osteoclast cytoskeletal function and survival. They are approved for osteoporosis, Paget's disease, hypercalcaemia of malignancy, and bone metastases, where they significantly reduce fracture risk and skeletal-related events. Observational and secondary-analysis data suggest broader aging-relevant effects: zoledronate (intravenous, annual) was associated with reduced all-cause mortality in a randomised trial in patients with recent hip fracture (HORIZON Recurrent Fracture Trial; Lyles et al., 2007, NEJM) and in observational cohorts, and bisphosphonate use has been associated with reduced breast, colorectal, and possibly other cancers in several epidemiological studies, though residual confounding cannot be excluded. Geroscience interest centres on possible senolytic-adjacent effects — bisphosphonates deplete osteoclast progenitors and may selectively reduce calcification-associated senescent cell burden — but these mechanisms are hypothetical in humans. Side effects include oesophageal irritation, osteonecrosis of the jaw (rare, mainly with high-dose intravenous use), and atypical femoral fractures with prolonged therapy.

BPC-157 is a synthetic 15-amino-acid peptide derived from a sequence in human gastric juice, marketed for tendon, ligament, and gut healing. Animal studies suggest pro-angiogenic and tissue-repair effects, but human clinical-trial data are very limited, comprising only a small number of pilot studies with no large well-controlled RCTs. It is not approved by the FDA or EMA. Injectable BPC-157 was placed on the FDA 503A Category 2 (significant safety concerns) interim bulk drug substances list and was removed from Category 2 on 22 April 2026 alongside eleven other peptides whose nominators withdrew, pending a Pharmacy Compounding Advisory Committee (PCAC) review scheduled for 23–24 July 2026; this is not an approval, and BPC-157 remains unauthorised for any therapeutic indication and prohibited at all times under WADA category S0 (Unapproved Substances).

Canakinumab (Ilaris, Novartis) is a fully human IgG1κ monoclonal antibody that neutralizes interleukin-1β. The FDA approved it in 2009 for cryopyrin-associated periodic syndromes (CAPS) and later for other autoinflammatory diseases (TRAPS, HIDS/MKD, FMF, Still's disease, sJIA); the EMA gave a parallel centralized authorization. In CANTOS, 150 mg subcutaneously every 3 months reduced the rate of recurrent major adverse cardiovascular events by ~15% in post-MI patients with hsCRP ≥2 mg/L, independent of LDL-cholesterol lowering, and an exploratory analysis suggested lower lung-cancer incidence and mortality. Canakinumab is not labeled for atherosclerosis or cancer in 2026, and high price plus increased serious-infection risk have limited cardiovascular adoption. After the FDA declined an atherosclerosis indication in 2018, Novartis announced it would not pursue further CV-indication filings for canakinumab.

Cerebrolysin is a porcine-brain–derived peptide preparation manufactured by EVER Pharma (Austria), containing low-molecular-weight neuropeptides and free amino acids and marketed for neurorestoration after ischaemic stroke, traumatic brain injury, and vascular or Alzheimer dementia. It is authorized as a prescription medicine in roughly 50 countries — including Austria, Germany (national authorization), Russia, China, and several CEE and Asian markets — but has no centralized EMA approval and is not FDA-approved. The Cochrane review by Ziganshina et al. (2017, most recently updated 2023, pub7) on acute ischaemic stroke found no demonstrable clinical benefit and a signal of more non-fatal serious adverse events; meta-analyses in vascular dementia and TBI show small, heterogeneous effects on cognitive scales. Use as a longevity or general anti-aging intervention is off-label and unsupported by current trial evidence.

Colchicine is a plant-derived alkaloid from the autumn crocus (*Colchicum autumnale*) that exerts anti-inflammatory effects by binding tubulin and disrupting microtubule polymerization, impairing neutrophil migration and inhibiting assembly of the NLRP3 inflammasome — a cytoplasmic complex that generates IL-1β and IL-18, two cytokines linked to atherosclerotic plaque progression. At 0.5 mg once daily — far below doses used in gout — it attenuates chronic vascular inflammation without broad immunosuppression. Its relevance to aging biology rests on inflammaging: the low-grade, sterile inflammatory state that accumulates with age and accelerates cardiovascular disease, making colchicine a pharmacological tool to interrupt one causal pathway linking aging to major adverse cardiovascular events (MACE). Clinical trial evidence is strong: the COLCOT trial (n = 4,745) showed a 23% relative reduction in MACE in patients randomized within 30 days of myocardial infarction (Tardif et al., NEJM 2019); LoDoCo2 (n = 5,522) demonstrated a 31% reduction in cardiovascular events in stable chronic coronary disease over a median 28.6 months (Nidorf et al., NEJM 2020). The FDA approved colchicine 0.5 mg (Lodoco) in June 2023 for secondary cardiovascular prevention. The 2023 AHA/ACC guideline assigns a Class IIb recommendation for patients with residual inflammatory risk; gastrointestinal side effects are the main tolerability concern, and interaction with CYP3A4/P-gp inhibitors requires dose vigilance.

CRISPR-based therapies use CRISPR-Cas9, base editors, or prime editors to make targeted, somatic edits to DNA either ex vivo (in harvested cells) or in vivo (directly in the patient). The first regulator-approved CRISPR medicine, Casgevy (exagamglogene autotemcel, Vertex/CRISPR Therapeutics), was approved by the FDA on 8 December 2023 and by the European Commission in February 2024 for sickle cell disease and transfusion-dependent β-thalassaemia in patients aged 12+, based on the Frangoul et al. NEJM 2021 trial. Longevity-oriented applications — telomerase reactivation, knockout of senescence or progeroid genes, in-vivo PCSK9 base editing (Verve Therapeutics VERVE-102) and in-vivo ANGPTL3 editing (CRISPR Therapeutics CTX310; NEJM 2025 phase-1 readout showed, at the highest dose, mean LDL −49 % and triglyceride −55 % reductions) — have produced phase-1 cardiovascular readouts but remain preclinical for any aging endpoint; no CRISPR therapy is approved for an aging indication as of 2026.

Cycloastragenol is the aglycone of astragaloside IV, a cycloartane-type triterpenoid hydrolysis product from Astragalus membranaceus root. In cellular assays it produces mild, transient activation of telomerase reverse transcriptase (TERT) and has been reported to improve cardiac, neurological, and metabolic readouts in rodent models. Human data are limited to small studies of the proprietary TA-65 preparation; no independent rigorous RCT exists for free-form cycloastragenol on aging endpoints. Subchronic toxicity and genotoxicity studies support food-supplement use, and cycloastragenol is sold in the US under DSHEA and in the EU as a food supplement, but it has no approved drug indication in any jurisdiction as of 2026.

D+Q is one of the most studied senolytic combinations: dasatinib (a tyrosine-kinase-inhibitor cancer drug) plus quercetin (a flavonoid), given intermittently and designed to selectively eliminate or reduce senescent-cell burden. Preclinical studies show improvements in physical function and tissue health in aged mice. Human data are limited to small pilot trials in IPF, diabetic kidney disease, and frailty, which have shown reductions in senescence markers; efficacy as an anti-aging therapy remains unproven and use is off-label. D+Q is now joined in the senolytic landscape by additional programmes such as Unity Biotechnology's UBX1325 (foselutoclax), which reported peer-reviewed BEHOLD data in NEJM Evidence in April 2025 and subsequent 36-week Phase 2b ASPIRE data via company press release in May 2025.

Denosumab is a fully human IgG2 monoclonal antibody that binds and neutralizes RANKL (receptor activator of nuclear factor-κB ligand), the cytokine required for osteoclast differentiation, activation, and survival; by blocking the RANK–RANKL axis it profoundly suppresses bone resorption. It is FDA-approved for osteoporosis in postmenopausal women and men at high fracture risk (Prolia, 60 mg SC every 6 months), prevention of skeletal-related events in bone metastases (Xgeva, higher dose), and giant cell tumour of bone. Unlike bisphosphonates, RANKL inhibition also affects immune cells and tumour microenvironments because RANKL is expressed on osteoblasts, activated T cells, and stromal cells beyond bone; this has prompted research into oncological and immunological applications. Observational data suggest possible cardiovascular and all-cause mortality reductions in denosumab-treated osteoporosis patients beyond fracture prevention, paralleling findings with bisphosphonates, but confounding and frailty-bias complicate interpretation. A critical safety feature is rebound bone loss if therapy is discontinued without transitioning to a bisphosphonate, as osteoclast activity surges; rare osteonecrosis of the jaw and atypical femoral fractures are also reported.

DHEA (dehydroepiandrosterone) circulates mainly as DHEA-S and serves as precursor for peripheral synthesis of testosterone and estradiol. Serum DHEA-S peaks in early adulthood and falls by roughly 80% by age 70–80 (adrenopause). The enzyme 3β-hydroxysteroid dehydrogenase converts DHEA to androgens and estrogens in peripheral tissues, producing tissue-specific, sex-dependent effects. The DHEAge Study (Baulieu et al. 2000, n=280, age 60–79) randomised participants to 50 mg oral DHEA or placebo for one year; bone density and skin hydration improved in older women, but body composition, muscle strength, and cognition were unaffected. A meta-analysis of 10 RCTs in women with adrenal insufficiency (Alkatib et al. 2009) found only a small quality-of-life benefit (effect size 0.21). The DAWN Trial (Kritz-Silverstein et al. 2008) found no benefit on cognition or well-being in healthy older adults. A 2025 Mendelian randomisation study (Schooling & Zhao) linked genetically higher DHEA-S to shorter lifespan in men (−1.15 years per logged µmol/L) but not in women, arguing against a causally favourable longevity effect. Safety concerns include stimulation of hormone-sensitive cancers; DHEA is sold over the counter in the USA but is prescription-only in most of Europe.

Donanemab is a humanised IgG1 monoclonal antibody directed against the pyroglutamate-modified N-terminus of amyloid-beta (N3pG), an epitope found almost exclusively in established plaques. In the phase 3 TRAILBLAZER-ALZ 2 trial it slowed clinical decline by 22 to 36 percent on the Integrated Alzheimer Disease Rating Scale and CDR-SB over 76 weeks in early symptomatic Alzheimer disease, with greater effect in low/medium tau participants. Treatment can be stopped once amyloid clearance is achieved on PET. The FDA approved donanemab on 2 July 2024. The European Medicines Agency initially refused approval on 27 March 2025 but recommended approval after re-examination on 24 July 2025, and the European Commission granted marketing authorisation on 24 September 2025, restricted to APOE epsilon-4 non-carriers and heterozygotes. ARIA-E occurred in roughly 24 percent of treated participants in TRAILBLAZER-ALZ 2. On 9 July 2025 the FDA approved an updated label with a modified titration schedule that lowered ARIA-E rates. UK MHRA approved donanemab on 23 October 2024 (NICE issued final non-recommendation on 19 June 2025); Japan's PMDA approved donanemab on 24 September 2024.

Epitalon (Ala-Glu-Asp-Gly) is a synthetic tetrapeptide developed in the 1980s–90s by Vladimir Khavinson's group at the St Petersburg Institute of Bioregulation and Gerontology, and proposed as a telomerase activator and pineal-gland modulator. The clinical literature is dominated by small, mostly unblinded studies from a single research network with serious methodological concerns (limited randomization, soft endpoints, no independent Western replication). Epitalon is not approved as a medicinal product by the FDA or EMA. The FDA placed it on the 503A Category 2 bulk-substance list in 2023, then removed it on 22 April 2026 alongside eleven other peptides whose nominators withdrew, with a formal PCAC consultation scheduled for 24 July 2026. It is sold internationally as a research peptide; longevity or telomerase claims are not supported by adequately powered, independently replicated trials.

Exosomes are extracellular vesicles of 30–150 nm diameter that originate from the endosomal multivesicular body pathway and carry a cargo of proteins, lipids, mRNAs, miRNAs, and other non-coding RNAs that can modulate gene expression and cell behaviour in recipient cells. In aging research, exosomes derived from young plasma or from mesenchymal stem cells (MSC-EVs) have shown rejuvenating effects in rodent models — improving cardiac function, cognitive performance, and tissue regeneration — and are proposed as a cell-free alternative to plasma transfusion or stem cell therapy with potentially lower immunogenic risk. Regulatory classification is contested: the FDA considers most exosome products as biologics subject to IND application for clinical use, and in 2019 issued a safety alert warning that exosome products marketed for anti-aging, orthopedic, or hair loss indications outside clinical trials have not demonstrated safety or efficacy. The clinical evidence base consists primarily of small pilot studies and case series; controlled randomised trial data in aging are absent. Standardisation of isolation method, cargo characterisation, potency assays, and dosing remains an unresolved challenge across the field, and exosome products sold directly at clinics should be viewed with significant caution.

Gene therapy delivers genetic material to add, silence, or edit genes — typically via AAV vectors for stable transgene expression and lipid nanoparticles for transient nucleic-acid delivery (e.g., mRNA, gene-editing components). Longevity targets include telomerase (TERT), follistatin, Klotho, and partial reprogramming via OSK (the three Yamanaka factors Oct4, Sox2 and Klf4 — omitting c-Myc to reduce oncogenicity). Rodent data are strong for some constructs, but human applications remain pre-clinical or run as small offshore or patient-paid programs outside FDA-regulated frameworks (BioViva, Libella). Risks include immunogenicity, oncogenicity, and off-target editing; no anti-aging gene therapy is approved.

GHK-Cu is the glycyl-L-histidyl-L-lysine tripeptide complexed with copper(II), a fragment of α2-macroglobulin whose plasma concentration declines with age. In topical cosmetic dermatology it has been marketed for decades for wound healing, skin remodeling, and hair growth; supportive human trials are small and the broader literature is mechanistic and in-vitro (modulation of >4000 genes, fibroblast and angiogenic effects). Topical cosmetic preparations remain widely sold in the EU and US under cosmetic-regulation pathways, but no GHK-Cu drug product is FDA- or EMA-approved. Injectable GHK-Cu was placed on the FDA 503A Category 2 list in 2023, removed from Category 2 on 22 April 2026 alongside eleven other peptides whose nominators withdrew, and is scheduled for PCAC consultation before the end of February 2027.

GLP-1 receptor agonists (e.g. liraglutide, semaglutide, dulaglutide) mimic the incretin hormone glucagon-like peptide-1, stimulating glucose-dependent insulin secretion, suppressing glucagon, slowing gastric emptying, and reducing appetite. Approved indications include type 2 diabetes and obesity; large trials demonstrate reduced cardiovascular events, now-approved kidney-disease risk reduction in type 2 diabetes with chronic kidney disease (semaglutide, FDA January 2025, FLOW trial), and investigational heart-failure symptom improvements in HFpEF. Longevity-relevant effects include weight loss, improved glycemia, and possible neuroinflammatory dampening. Off-label use purely for healthspan extension in metabolically healthy adults remains investigational. On 21 February 2025 the FDA declared the US semaglutide shortage resolved, ending the 503A/503B compounding window for semaglutide; tirzepatide compounding was similarly restricted after a 2024 preliminary-injunction denial, and the FDA proposed a permanent 503B bulks exclusion for semaglutide, tirzepatide, and liraglutide on 30 April 2026.

Glucosamine is an endogenous amino sugar and structural precursor of glycosaminoglycans — polysaccharides that maintain cartilage hydration, elasticity, and compressive resistance. Sold as glucosamine sulfate or hydrochloride at 1500 mg/day, it is one of the most widely used joint supplements globally. Glucosamine partially inhibits glycolysis, mimicking carbohydrate restriction: in C. elegans and ageing C57BL/6 mice this shift activated AMPK, increased mitochondrial biogenesis, and extended lifespan (roughly 8% in nematodes; statistically significant in mice) (Weimer et al., Nature Communications 2014). A UK Biobank cohort of 495,077 adults (Li et al., Annals of the Rheumatic Diseases 2020) found glucosamine use associated with 15% lower all-cause mortality (HR 0.85, 95% CI 0.82–0.89) and 18% lower CVD mortality (HR 0.82, 95% CI 0.74–0.90) over 8.9 years. Suissa et al. (Pharmacoepidemiology and Drug Safety 2022) showed these estimates likely reflect collider stratification bias in prevalent-cohort designs, which can produce spurious 15–20% mortality reductions when the true effect is null. No randomised trial has tested a mortality endpoint; guidelines endorse glucosamine only for symptomatic knee osteoarthritis, where structural benefit evidence remains mixed.

Growth hormone (GH, somatropin) is a peptide hormone secreted by the anterior pituitary that regulates body composition, bone density, and metabolism primarily through hepatic production of insulin-like growth factor 1 (IGF-1). After the third decade, GH pulse amplitude and daily secretion decline roughly 14% per decade — termed somatopause — leading to reduced IGF-1, increased visceral adiposity, and loss of lean mass. The landmark Rudman 1990 trial (NEJM) showed six months of recombinant GH in 21 men aged 61–81 increased lean body mass by 8.8% and reduced adipose tissue by 14.4%; Rudman himself cautioned the study had no anti-aging implications. A central paradox complicates the picture: in C. elegans, Drosophila, and multiple mouse strains (Ames dwarf, Snell dwarf, GH-receptor knockout), reduced GH/IGF-1 signaling extends lifespan by 40–65%, while humans with Laron syndrome (congenital GH-receptor deficiency) show near-zero cancer incidence and diminished diabetes risk despite severe short stature. In older adults, GH replacement improves body composition but has not demonstrated benefits in functional capacity, cognition, or survival, and carries substantial risks — insulin resistance, fluid retention, arthralgias, carpal tunnel syndrome, and a theoretical increase in cancer promotion via IGF-1-driven mitogenic signalling. Aguiar-Oliveira and Bartke (Endocrine Reviews 2019) concluded that current evidence does not support off-label GH use for healthy aging; approved indications remain restricted to documented adult GH deficiency of pituitary origin.

Heterochronic parabiosis (HCP) is an experimental surgical technique in which the circulatory systems of a young and an old animal are joined by anastomosis of subcutaneous vasculature, exposing each partner continuously to the other's blood. Classic studies by Clive McCay in the 1950s and a revival by Irina and Michael Conboy (2005, Nature), Amy Wagers, Saul Villeda, and colleagues in the 2000s–2010s showed that old mice conjoined with young partners exhibit improvements in muscle regeneration, neurogenesis, cardiac hypertrophy, and liver function, while young mice show partial deterioration. Two competing mechanistic hypotheses emerged: the young-factors model, proposing that circulating rejuvenating factors in young blood are responsible — highlighted by controversy over GDF11, which was initially championed and then disputed as a beneficial rejuvenation factor — and the dilution model, proposed by Irina Conboy and colleagues, arguing that dilution of pro-aging factors (TGF-β, β2-microglobulin) accumulated in old blood is the dominant mechanism, a view supported by experiments using young saline-albumin exchange rather than young blood specifically. Human translation efforts include Alkahest (a 2014 spin-out from Tony Wyss-Coray's Stanford lab, with Saul Villeda as a scientific advisor), which has fractionated plasma into defined protein fractions (GRF6019) for Alzheimer's and Parkinson's trials, and small commercial young-plasma infusion services that preceded regulatory scrutiny; the FDA issued a safety alert in 2019 warning against unproven commercial young-plasma infusions. No plasma-based therapy for aging is currently approved by the FDA or EMA.

Menopausal HRT replaces estrogen, typically combined with a progestogen in women with a uterus, to relieve vasomotor symptoms, protect bone, and treat genitourinary symptoms. Per WHI re-analyses and the timing hypothesis, the benefit-risk profile is more favorable when initiated within roughly ten years of menopause or before age 60. VTE risk is greater with oral estrogen than with transdermal preparations, and breast cancer risk is greater with combined estrogen+progestogen than estrogen-alone, rising with duration. It is symptom- and risk-directed therapy, not a proven life-extension intervention.

Humanin is a 24-amino-acid mitochondrial-derived peptide encoded in the 16S rRNA region of mtDNA, originally identified by Hashimoto and Nishimoto in surviving neurons of Alzheimer brains. In cell and rodent models it is anti-apoptotic (binds Bax, IGFBP-3) and neuroprotective against amyloid-β toxicity, and circulating humanin declines with age in mice, macaques, and humans. There is no approved indication for humanin or its analogues anywhere in the world as of 2026; all evidence is preclinical or observational, with no completed phase-3 human efficacy trial. Synthetic humanin and analogues such as HNG circulate as research peptides only.

Klotho is a transmembrane protein and co-receptor for FGF23 that declines markedly with age; its soluble circulating form (s-Klotho) suppresses Wnt and TGF-β signalling and has been associated with renal function, cognitive health, and cardiovascular protection in observational studies. In mouse models, transgenic Klotho overexpression has extended lifespan (Kurosu et al., 2005), and AAV-mediated Klotho gene therapy has improved kidney function and rescued cognitive deficits in disease models. In aged rhesus macaques, peripheral injection of recombinant Klotho protein — not gene therapy — enhanced cognition (Castner et al., 2023); AAV-Klotho gene therapy in primates has not yet been published. Human longevity application remains strictly preclinical; BioViva and affiliated researchers have reported self-administered gene therapy experiments in single individuals outside regulated clinical frameworks, but these lack controlled safety or efficacy data and should not be interpreted as evidence of benefit. Risks include disruption of FGF23-phosphate homeostasis (potentially hypophosphatemia/hyperphosphaturia) and the general immunogenicity and off-target concerns of systemic AAV delivery; note that vascular calcification is a phenotype of Klotho deficiency, so overexpression is expected to be protective rather than calcifying.

Lecanemab is a humanised IgG1 monoclonal antibody that binds soluble amyloid-beta protofibrils and, to a lesser degree, fibrillar plaques. In the phase 3 CLARITY-AD trial it slowed decline on the Clinical Dementia Rating Sum of Boxes by 0.45 points over 18 months in early Alzheimer disease versus placebo. The FDA granted accelerated approval on 6 January 2023 and traditional approval on 6 July 2023. The European Medicines Agency initially refused the marketing authorisation in July 2024 but reversed after re-examination, and the European Commission granted approval on 15 April 2025, restricted to APOE epsilon-4 non-carriers and heterozygotes. The main safety concern is amyloid-related imaging abnormalities (ARIA-E oedema, ARIA-H microhaemorrhage), which are markedly more frequent and severe in APOE epsilon-4 homozygotes. On 30 August 2025 the FDA approved a once-weekly subcutaneous autoinjector formulation (LEQEMBI IQLIK) for maintenance dosing, the first anti-amyloid antibody with at-home administration. NICE issued final guidance on 19 June 2025 not recommending lecanemab for routine NHS use, with a third consultation opened in 2026; Germany's G-BA found kein Zusatznutzen on 19 February 2026.

Trace lithium exposure from drinking water (~0.01–0.1 mg/L) has been associated with lower all-cause mortality in ecological studies in Japan, Texas, and Europe; the proposed mechanism is GSK-3β inhibition and induction of autophagy, with extension of lifespan demonstrated in C. elegans. Therapeutic-dose lithium carbonate (300–1800 mg/day) is approved worldwide for bipolar disorder and has neuroprotective signals, but is constrained by renal, thyroid, and parathyroid toxicity at long-term use. Microdose lithium orotate (1–5 mg elemental lithium) is sold as a dietary supplement in the US under DSHEA and as a food supplement (Nahrungsergänzungsmittel) in Germany — it is not a licensed medicine, and BfArM has historically treated higher-strength preparations as medicinal. No adequately powered RCT supports a longevity indication. In August 2025 the Yankner group reported (Liu et al., Nature) that endogenous brain lithium is depleted in mild cognitive impairment and Alzheimer disease, with amyloid-β sequestering available lithium; a small 2026 JAMA Neurology pilot RCT (n≈80) in MCI did not meet its primary endpoint but reported a verbal-memory signal. Neither establishes a longevity indication.

Mesenchymal stem cells (MSCs) are multipotent stromal progenitors capable of differentiating into osteoblasts, chondrocytes, and adipocytes, and are isolated from bone marrow, adipose tissue, umbilical cord (Wharton's jelly), placenta, and dental pulp, with umbilical cord-derived MSCs increasingly favoured for allogeneic use due to lower immunogenicity and higher proliferative capacity. Despite early assumptions of direct tissue engraftment and replacement, current evidence indicates that transplanted MSCs rarely engraft stably at target tissues; instead, the dominant mechanism of action is paracrine, mediated by secreted cytokines, growth factors, extracellular vesicles (exosomes and microvesicles), and mitochondrial transfer, which modulate local immune responses, reduce fibrosis, support angiogenesis, and dampen senescent cell secretome activity. In age-related and chronic disease contexts, MSC therapies have been investigated in clinical trials for osteoarthritis, graft-versus-host disease, Crohn's disease, heart failure, COPD, and frailty, with graft-versus-host disease being the setting with the most established regulatory acceptance in some jurisdictions. For aging and longevity applications specifically, small trials have reported functional improvements in frailty endpoints, but sample sizes, follow-up durations, and outcome standardization remain insufficient for definitive conclusions. Regulatory status varies by region: the EMA and FDA require approval as advanced-therapy medicinal products (ATMPs) or biologics, and many administered products operate outside approved frameworks. Long-term safety data, including oncogenicity risk from repeated dosing, are not fully established.

Metformin is a biguanide oral antidiabetic drug, first-line therapy for type 2 diabetes mellitus. It lowers hepatic gluconeogenesis and improves insulin sensitivity, partly via mitochondrial complex I inhibition and indirect AMPK activation. Observational data suggest reduced all-cause mortality and cancer incidence in diabetics, motivating the proposed TAME trial (Targeting Aging with Metformin), which as of mid-2026 has not yet enrolled at scale, with funding and protocol revisions ongoing. Off-label longevity use remains investigational; benefit in metabolically healthy people is unproven and may even blunt exercise adaptations.

Methylene blue (MB) is a synthetic phenothiazine dye with FDA approval (Provayblue, 2016) for treatment of acquired methemoglobinemia at an initial dose of 1 mg/kg intravenously, with a repeat dose of 1 mg/kg if needed (total up to 2 mg/kg). At low concentrations (nanomolar to low micromolar), it acts as a redox cycler in the mitochondrial electron transport chain, accepting electrons from NADH and donating them to cytochrome c, thereby bypassing dysfunctional complexes I and III and supporting ATP synthesis. In cell culture and rodent models, low-dose MB has reduced mitochondrial reactive oxygen species, improved memory in aged animals, and attenuated neurodegeneration-related pathology. Interest in MB for aging stems partly from a small number of human trials investigating cognitive effects in healthy older adults or early Alzheimer's disease, with mixed and modest results; no aging or longevity indication has been approved, regulatory frameworks for low-dose oral use vary by country, and recommendations for off-label use as a longevity agent are unsupported by RCT evidence.

Mitochondrial transplantation involves the direct transfer of intact, metabolically functional mitochondria — isolated from autologous or allogeneic tissue — into ischaemic or otherwise bioenergetically compromised cells or organs to supplement or replace dysfunctional mitochondria. The best-documented clinical context is paediatric cardiac surgery: McCully and colleagues (Boston Children's Hospital) reported in a preliminary 2017 JTCVS communication that autologous mitochondria injected into ischaemia-injured myocardium improved ventricular function in children with postcardiotomy ECMO-dependent cardiogenic shock; a larger 2020 JTCVS case series (n=24) showed 80% successful ECMO separation versus 29% in controls. This application is now in early clinical study (NCT02851758). Mechanistic proposals include import via clathrin-mediated endocytosis, macropinocytosis, and direct membrane fusion, though the dominant uptake pathway and long-term mitochondrial survival in recipient cells remain under investigation. Application to aging is hypothetical: in preclinical models, intravenous mitochondrial infusion has been reported to improve muscle function and cognitive markers in aged rodents, but the route, source tissue, dosing, and safety profile for systemic aging applications are not established, and no approved indication for aging exists.

MOTS-c is a 16-amino-acid mitochondrial-derived peptide encoded within the mitochondrial 12S rRNA region. In rodent studies it activates AMPK, inhibits the folate-purine cycle, and improves insulin sensitivity, glucose homeostasis, and exercise capacity; circulating MOTS-c rises transiently with exercise, which is the basis for the popular "exercise mimetic" framing. Human data are limited to small observational studies of endogenous levels. MOTS-c is not approved as a medicinal product by the FDA, EMA, PMDA, or NMPA as of 2026. The FDA added MOTS-c to the 503A Category 2 bulk-substance list in 2023 (peptides flagged as raising significant safety risks for compounding), then removed it on 22 April 2026 alongside 11 other peptides whose nominators withdrew, with formal PCAC review scheduled for July 2026; outside that pending review it still circulates only as a research-use peptide.

Navitoclax (ABT-263) is an orally bioavailable BH3 mimetic that inhibits BCL-2, BCL-xL, and BCL-W by binding their BH3-interaction groove and displacing pro-apoptotic effectors BAX and BAK, triggering the intrinsic apoptosis pathway. Senescent cells upregulate BCL-2 family members through their anti-apoptotic programme (SCAP); navitoclax exploits this as a senolytic. Chang et al. (Nature Medicine, 2016) showed oral ABT-263 depleted senescent hematopoietic stem cells in irradiated and naturally aged mice and restored self-renewal, providing the first in vivo evidence of pharmacological senolysis with tissue benefit. The primary obstacle is BCL-xL-dependent thrombocytopenia: platelets depend almost exclusively on BCL-xL for survival. Gandhi et al. (JCO, 2011, Phase I) found this dose-limiting at 325 mg/day continuous or 350 mg intermittent; Rudin et al. (Clin Cancer Res, 2012, Phase II) recorded Grade III-IV thrombocytopenia in 41% of patients. BCL-xL-directed PROTACs such as DT2216 and PZ15227 exploit low E3-ligase expression in platelets for comparable senolytic activity with reduced toxicity (Skwarska and Konopleva, Cancer Research, 2023). As of mid-2026, navitoclax has not entered trials for senescence clearance in healthy individuals.

Nicotinamide (NAM, also called niacinamide) is the amide form of vitamin B3 and a direct precursor in NAD+ biosynthesis via the salvage pathway enzyme NAMPT. It is biochemically distinct from the NAD+ precursors nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR): whereas NR and NMN feed into the salvage pathway before NAM's NAMPT entry point, NAM is the common end-product of NAD+ consumption by sirtuins, PARPs, and CD38, making intracellular NAM accumulation a feedback inhibitor of SIRT1 and other sirtuins at high concentrations. This dual role — both precursor and sirtuin inhibitor — complicates interpretation of supplementation studies and distinguishes it mechanistically from NR/NMN. NAM has established medical uses: topical niacinamide is widely used for acne and skin barrier function, and oral high-dose nicotinamide (500 mg twice daily) reduced actinic keratoses and non-melanoma skin cancer rates in a randomized trial in immunocompetent high-risk adults (Chen et al., 2015, NEJM); however, a subsequent phase 3 trial in solid-organ transplant recipients (ONTRANS; Allen et al., NEJM 2023) found no reduction in keratinocyte cancers or actinic keratoses, limiting confidence that the ONTRAC result generalises to the higher-risk transplant population. Its use as a systemic longevity supplement is investigational and the net effect on sirtuin-dependent processes at supplemented doses in humans is not established.

Peptide therapy uses short amino-acid chains, often injected, intended to modulate growth hormone (e.g., sermorelin, ipamorelin), tissue repair, or metabolism. A few peptides are approved for narrow indications, but most longevity uses are off-label or sourced as research chemicals. Human evidence for anti-aging endpoints is sparse, quality control of compounded products is variable, and regulatory bodies (e.g., FDA) have restricted several popular peptides.

Pioglitazone is a thiazolidinedione PPARγ agonist approved for type 2 diabetes mellitus as an insulin sensitizer, acting primarily by promoting the differentiation and lipid uptake of adipocytes, thereby reducing ectopic fat deposition and improving systemic insulin sensitivity. PPARγ activation also modulates inflammatory gene expression and macrophage polarization towards anti-inflammatory phenotypes, which has generated interest in pioglitazone for age-related conditions beyond glycaemic control. The IRIS trial (Kernan et al., 2016, NEJM) demonstrated reduced cardiovascular events in non-diabetic patients with insulin resistance and prior stroke or TIA. Nir Barzilai and colleagues have included pioglitazone in geroscience cohort discussions as a candidate that addresses metabolic and inflammatory hallmarks of aging. Long-term safety concerns include risk of congestive heart failure, bone loss, and a possible association with bladder cancer; France and Germany suspended use in 2011 following safety signals, and the EMA did not withdraw authorisation EU-wide but added contraindications (active or past bladder cancer, uninvestigated haematuria) and strict labelling restrictions, limiting its investigational use as a longevity agent.

Plasmapheresis is the umbrella term for extracorporeal procedures that separate plasma from cellular blood components; technique varies, with plasma either fractionated or filtered and partially returned, or wholly removed and replaced as in TPE. It is established for autoimmune and hyperviscosity disorders, where its dominant mechanism is removal of pathogenic plasma factors such as antibodies, immune complexes, and inflammatory mediators. In longevity contexts it is proposed to dilute pro-aging plasma factors, but evidence for healthy-aging benefit is preliminary.

Rapamycin (sirolimus) is a macrolide mTORC1 inhibitor approved as an immunosuppressant to prevent kidney transplant rejection and to treat lymphangioleiomyomatosis. By inhibiting mTORC1, it slows protein synthesis, enhances autophagy, and extends lifespan in yeast, worms, flies, and mice across multiple labs. Off-label use for human longevity remains investigational; clinical trials are evaluating intermittent low-dose protocols, but efficacy and long-term safety in healthy adults are unproven. The PEARL trial (Moel et al., Aging-US April 2025) reported safety similar across groups; the primary efficacy endpoint of visceral adipose tissue change was not met, but secondary outcomes showed dose-dependent improvements in lean mass and pain in women on 10 mg/week.

Retatrutide (LY3437943) is an investigational once-weekly subcutaneous peptide by Eli Lilly that simultaneously activates the GLP-1 receptor (GLP-1R), the glucose-dependent insulinotropic polypeptide receptor (GIPR), and the glucagon receptor (GCGR). GLP-1R agonism suppresses appetite and slows gastric emptying; GIPR agonism amplifies glucose-dependent insulin secretion and sensitizes adipose tissue to GLP-1; GCGR agonism raises resting energy expenditure through hepatic fat oxidation and, in preclinical models, brown-adipose thermogenesis, a mechanism absent from dual agonists such as tirzepatide. The phase 2 obesity trial (Jastreboff et al., NEJM 2023) found a mean 24.2% body weight reduction at 48 weeks with 12 mg; approximately half of participants exceeded 25% loss, and liver fat declined by a mean of 82.4% at 24 weeks. A concurrent phase 2 trial in type 2 diabetes (Rosenstock et al., Lancet 2023) showed greater HbA1c and weight reductions vs. placebo and dulaglutide 1.5 mg. Phase 3 TRIUMPH-1 topline data (May 2026) reported 28.3% mean weight loss at 80 weeks with 12 mg in 2 339 adults with obesity without diabetes. Retatrutide remains investigational; no regulatory approval had been granted as of mid-2026, and long-term cardiovascular outcomes are not yet established.

Semaglutide is a long-acting GLP-1 receptor agonist approved for type 2 diabetes (Ozempic, Rybelsus) and chronic weight management (Wegovy). The SELECT trial demonstrated a 20 percent reduction in major adverse cardiovascular events in adults with obesity and established cardiovascular disease without diabetes. Longevity-relevant mechanisms include sustained weight loss, improved insulin sensitivity, lower inflammation, and possible cognitive and renal protection. Off-label use solely for lifespan extension in healthy adults is investigational and not endorsed.

A senescent-cell vaccine is an immunological strategy aimed at training the adaptive immune system to recognize and eliminate senescent cells in vivo, analogous to anti-tumour vaccination. The approach was demonstrated preclinically by Suda and colleagues (2021, Nature Aging): mice vaccinated with peptides derived from glycoprotein nonmetastatic melanoma protein B (GPNMB), a surface antigen overexpressed on senescent cells, developed anti-GPNMB antibody responses (humoral immunity) that selectively eliminated GPNMB-expressing senescent cells, reduced senescent cell burden, improved physical function, and partially replicated healthspan benefits seen with pharmacological senolytics in progeroid (Ercc1-mutant accelerated-aging) and diet-induced obese mouse models. The concept is in early discovery phase: GPNMB is not exclusively expressed on senescent cells, potential immune tolerance and autoimmunity risks have not been evaluated in humans, no clinical trial has been initiated, and whether a single antigen target can cover the heterogeneous senescent cell landscape across tissues remains unresolved. This is a preclinical proof-of-concept, not an available or approaching clinical product.

Senolytic therapy uses drugs or natural compounds to selectively eliminate senescent cells, which accumulate with age and secrete a multi-component secretome (the SASP) of inflammatory cytokines and chemokines, growth factors, and tissue-remodeling proteases such as MMPs. By targeting senescent-cell anti-apoptotic pathways (SCAPs) and promoting selective apoptosis in these cells, senolytics aim to reduce age-related dysfunction. Evidence is robust in animal models, but human trials remain small and early; clinical efficacy, optimal dosing, and long-term safety are unproven. The Unity Biotechnology UBX1325 (foselutoclax) BEHOLD trial in diabetic macular oedema, with peer-reviewed results in NEJM Evidence (April 2025), is the most advanced human senolytic programme to date; the Phase 2b ASPIRE 36-week readout was subsequently reported via a Unity press release in May 2025.

Sermorelin is a synthetic 29-amino-acid analogue of endogenous growth hormone-releasing hormone (GHRH 1–29) that stimulates pituitary somatotrophs to secrete growth hormone (GH) in a pulsatile, feedback-sensitive manner, in contrast to exogenous GH administration which suppresses endogenous production. It was formerly FDA-approved for paediatric GH deficiency (Geref); the manufacturer voluntarily discontinued the product in 2008 for commercial reasons, and the FDA's 2013 Federal Register notice formally determined that Geref had not been withdrawn from sale for reasons of safety or effectiveness. Sermorelin remains approved in some other jurisdictions. In anti-aging medicine, sermorelin is widely prescribed off-label at clinics that advertise effects on GH/IGF-1 axis activity, body fat, lean mass, and sleep quality in middle-aged and older adults. Controlled evidence for meaningful longevity or functional outcomes is limited, and the GH secretagogue class broadly lacks Phase III efficacy data for aging indications. Adverse effects include injection-site reactions, fluid retention, and theoretical concern about promotion of occult neoplasia given GH/IGF-1 mitogenic signalling; its use is not endorsed by major endocrinological societies for anti-aging purposes.

SGLT2 inhibitors (gliflozins, e.g. empagliflozin, dapagliflozin) block renal sodium-glucose cotransporter 2, causing urinary glucose excretion. They are approved for type 2 diabetes, heart failure (preserved and reduced ejection fraction), and chronic kidney disease, with robust cardiovascular and renal mortality benefits. Proposed mechanisms include a hypothesized ketone-mediated cardiac fuel shift, mild caloric loss, and reduced glomerular hyperfiltration, though the dominant pathway remains debated. Canagliflozin extended lifespan in male mice. Off-label longevity use in non-indicated adults remains investigational.

Statins (HMG-CoA reductase inhibitors, e.g. atorvastatin, rosuvastatin) lower hepatic cholesterol synthesis and upregulate LDL receptors, reducing circulating LDL cholesterol. They are approved for primary and secondary prevention of atherosclerotic cardiovascular disease, with strong randomized evidence for reduced cardiovascular mortality. Longevity-relevant pleiotropic effects include endothelial improvement, anti-inflammatory action, and possible plaque stabilization. In low-risk individuals, the absolute mortality benefit is small and less certain; benefit is most clearly demonstrated in higher-risk and secondary prevention populations. Off-label use purely for longevity is investigational.

TA-65 is a proprietary, purified cycloastragenol-enriched extract from Astragalus membranaceus, marketed by T.A. Sciences (licensed by Geron) and sold as a telomerase-activating dietary supplement. Human data are sparse: Salvador et al. (Rejuvenation Research, 2016) reported a 1-year randomized double-blind placebo-controlled trial in 117 CMV-positive adults with modest effects on telomere length, and a subsequent 500-subject Geriatrics trial reported a small reduction in senescent CD8+CD28− T-cells. No rigorous RCT shows benefit on hard healthspan endpoints (frailty, mortality, dementia, cardiovascular events). In 2018 the FTC issued a complaint and final consent order against marketing claims; TA-65 is regulated in the US as a dietary supplement under DSHEA, not as an approved drug, and the EU treats astragalus extracts as food supplements.

Telomerase reverse transcriptase (TERT) is the catalytic subunit of telomerase; its somatic expression is repressed in most adult human tissues, leading to progressive telomere shortening with each cell division. AAV-delivered TERT transgenes have extended median lifespan, delayed frailty, and improved metabolic and neuromuscular phenotypes in middle-aged and old mice in work from the Blasco laboratory, with a single administration showing lasting effects without elevated cancer incidence in the mouse models studied. Human longevity application remains preclinical; the concern that telomerase activation could promote tumour growth by enabling unlimited replicative capacity in cells harbouring oncogenic mutations is a central safety caveat that has not been resolved in human data. Self-administered TERT gene therapy by individuals outside regulated trials (reported in the context of BioViva/Andrews) lacks peer-reviewed safety or efficacy evaluation and represents an extreme scientific and safety risk.

TRT restores testosterone in men with documented hypogonadism (low serum testosterone plus symptoms), via gels, injections, or pellets. Benefits include improved libido, mood, lean mass, and bone density. Risks include erythrocytosis, fertility suppression, and cardiovascular effects; the recent TRAVERSE trial suggested cardiovascular non-inferiority but not benefit, though TRAVERSE also found increased rates of atrial fibrillation and venous thromboembolism in the testosterone arm. TRT is not validated as a longevity therapy in eugonadal men and remains controversial outside clinical hypogonadism.

TPE is a specific form of plasmapheresis in which approximately one to one-and-a-half plasma volumes are removed and replaced per session with albumin, saline, or donor plasma, rather than re-infused. It is standard of care for several neurologic and hematologic diseases. Longevity interest stems from rodent dilution studies suggesting rejuvenation; small human trials (e.g., in Alzheimer's) are early and ongoing, with no proven anti-aging benefit.

Thymosin α-1 (Tα1) is a 28-amino-acid peptide derived from prothymosin α, naturally produced by thymic epithelial cells, that modulates innate and adaptive immunity by activating TLR signalling in dendritic cells and monocytes and promoting Th1-type T-cell responses. The thymus undergoes substantial involution from early adulthood, and declining thymic output with age contributes to T-cell senescence and immune ageing; Tα1 supplementation is proposed to partially compensate for this deficit. Thymalfasin (Zadaxin, SciClone Pharmaceuticals) is approved in over 35 countries — but not the United States — as an adjunct therapy for chronic hepatitis B and C and as an immunostimulant in patients with impaired immunity; it has been used off-label during COVID-19 outbreaks in several countries. Human evidence for anti-aging or longevity benefit is absent; trials in cancer and infection support immunomodulatory activity, but effect sizes and consistency vary. Tα1 is widely marketed by anti-aging clinics; its regulatory classification ranges from approved drug to unregulated peptide depending on jurisdiction. FDA added thymosin α-1 to Category 2 of the interim 503A bulks list on 29 September 2023; the substance was removed from Category 2 effective 27 September 2024 after the nominator withdrew its nomination, and on 4 December 2024 the FDA Pharmacy Compounding Advisory Committee (PCAC) voted against its inclusion on the 503A allowed bulks list, leaving it not eligible for use in 503A compounding in the US.

Tirzepatide is a once-weekly dual GIP and GLP-1 receptor agonist approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound). The dual incretin action produces greater weight loss and HbA1c reduction than selective GLP-1 agonists in head-to-head trials; the FDA approved Zepbound for moderate-to-severe obstructive sleep apnea in adults with obesity in December 2024. Cardiovascular outcomes were non-inferior to dulaglutide in the SURPASS-CVOT trial (3-point MACE 12.2% vs 13.1% over a median ~4 years; HR 0.92, 95.3% CI upper limit <1.0), reported in late 2025. Longevity-relevant effects parallel GLP-1 agonists: improved metabolism, weight reduction, and reduced cardiometabolic risk. Off-label use in metabolically healthy adults for lifespan extension remains investigational.

Urolithin A is a gut-derived metabolite produced when colonic bacteria transform ellagitannins and ellagic acid — polyphenols found in pomegranates, walnuts, and berries — via species such as Gordonibacter urolithinfaciens; because the requisite microbiome varies between individuals, dietary ellagitannin intake does not reliably raise urolithin A levels in all people. The compound activates mitophagy through mechanisms including inhibition of prohibitin-2 and indirect PINK1/Parkin pathway engagement, and improves mitochondrial respiration in preclinical models. In human randomized trials, a phase I safety and biomarker study (Andreux et al., 2019) established tolerability in older adults, while the ATLAS trial (Singh et al., 2022) in overweight middle-aged adults showed improvements in skeletal muscle mitophagy markers, aerobic endurance, and muscle strength as secondary endpoints; the primary endpoint (peak power output) was not met, and both trials were conducted by Amazentis, the commercial developer. Regulatory status: sold as a dietary supplement in many countries; not approved as a drug; longer-term safety and efficacy trials are ongoing.

Alpha-ketoglutarate (AKG) is a key intermediate of the tricarboxylic acid (TCA) cycle that also serves as an obligate co-substrate for a large family of dioxygenases — including TET methylcytosine hydroxylases and Jumonji-domain histone demethylases — that regulate the epigenome. Plasma AKG levels decline substantially with age in humans, which has motivated its supplementation in longevity research. In a 2020 mouse study (Asadi Shahmirzadi et al., Cell Metabolism), the calcium salt form (CaAKG) extended median lifespan in middle-aged female mice (roughly 10–17% depending on cohort, with ~20% extension at the 90th percentile in cohort 1) while males showed only a non-significant numerical trend; frailty was reduced in both sexes, though the trial was conducted in a single cohort rather than through the rigorous multi-site NIA Interventions Testing Program. A small 7-month open-label observational analysis of 42 self-selected users of the commercial formulation Rejuvant (Katcher et al., 2021) reported reductions in biological age as estimated by the TruAge DNA-methylation clock, but the study was industry-funded, single-arm without randomisation, and lacked a pre-registered primary endpoint. CaAKG is marketed as a supplement; no drug approval exists for aging indications, and independent replication in humans is absent.