Healthspan Weekly — Apr 20, 2026

The week's real story isn't any single result — it's a quiet convergence on the same design question: should longevity drugs be single-target or multi-target? Seragon Biosciences' company-funded combination drug outperformed rapamycin in mice, GHK-Cu (a copper peptide) is having a biohacker moment with evidence running well behind the hype, and Columbia University's Mailman School of Public Health published a report arguing the whole field is optimizing for the wrong number. Meanwhile, the FDA is quietly putting the biohacker peptide menu on an official 2026 agenda — which is how infrastructure actually changes.

• Cala kIQ Plus (Cala Health): FDA-cleared next-generation wearable neurostimulation system for action hand tremor in essential tremor and Parkinson's, delivering 40-minute wrist-worn sessions.
• Kardia 12L (AliveCor): CE-marked 12-lead handheld ECG system now cleared for distribution across the European Economic Area.
• SRN-901 peer-reviewed publication (Seragon Biosciences): Multi-pathway oral combination drug (urolithin A, quercetin, NR, alpha-lipoic acid, SRN-820) published in Drug Design, Development and Therapy April 15.
• OS-01 12-week clinical data (OneSkin): Topical senotherapeutic peptide trial reported ~18% reduction in trans-epidermal water loss at 12 weeks and directional improvement in systemic inflammation markers in the trial.
• Omada GLP-1 Care Track results (Omada Health): 12-week comparative study showing GLP-1 plus behavioral coaching produced greater fat loss with preserved lean mass versus control.

Most longevity drugs get tested in isolation against a placebo. Seragon Biosciences did something more interesting: they ran their drug head-to-head against rapamycin, NMN, and NR — same mice, same conditions. Their drug won.

Published April 15 in Drug Design, Development and Therapy, the paper reports that SRN-901 — an oral combination of urolithin A, quercetin, nicotinamide riboside, alpha-lipoic acid, and Seragon's proprietary SRN-820 — extended median remaining lifespan in 18-month-old mice by 33% in the study. Rapamycin, the field's mTOR benchmark, managed 21% in the same study. NMN and NR didn't significantly move the needle. Frailty progression was attenuated by roughly 70% versus placebo in the study, and tumor incidence dropped 30.5% in the study. Transcriptomic work showed upregulation of DNA repair alongside downregulation of inflammation, reactive oxygen species, and mTORC1 signaling.

A crucial nuance buried in most coverage: 33% refers to median remaining lifespan from 18 months — the increase in median total lifespan was 10.7% in the study. Still notable, but a different number than the headline suggests. The bigger asterisk: the study was funded by Seragon, and all authors except two are Seragon employees or shareholders. The combination-therapy thesis is scientifically sound and increasingly mainstream — aging is networked, so hitting multiple pathways should beat any single lever. But until an independent lab reproduces this, the correct posture is interested skepticism. Watch for whether an academic group picks this up for replication, and whether Seragon files for human trials. If neither happens within twelve months, that silence is its own signal.

Columbia's Mailman School of Public Health published a report this week naming something the longevity field has been quietly uncomfortable about for years: we've gotten very good at extending lifespan and very bad at keeping pace on healthspan. More people are making it into their 80s and 90s, but a significant share of those bonus years are spent managing chronic disease, cognitive decline, or functional dependency.

The report's argument is structural, not sentimental: research funding, trial design, and regulatory frameworks should explicitly prioritize functional capacity, cognitive independence, and quality of life as primary endpoints — not as secondary outcomes grudgingly collected after mortality. It lands alongside a JAMA Oncology secondary analysis of the GAP70+ trial showing that fewer than 1 in 10 older adults with advanced cancer prioritize extending survival over maintaining quality of life. When patients with real skin in the game actually get asked, they keep giving medicine the same answer. If major funders (NIA, Hevolution, ARPA-H) respond by reweighting their portfolios toward function-first endpoints, the effect compounds over a decade. If they don't, the longevity industry keeps measuring itself by a metric most of its customers don't actually want.

Your mitochondria don't just produce energy — how efficiently they produce it may be a master control on aging. A study in Aging Cell from researchers at Saitama Medical University and Chiba University identifies COX7RP as a protein that helps mitochondria form supercomplexes: tighter, more efficient configurations of the electron transport chain that burn the same fuel while producing more ATP and fewer reactive oxygen species.

Male mice engineered to produce extra COX7RP lived 6.6% longer on average in the study — modest, but meaningful in healthy animals, where most interventions only work in disease models. They showed improved insulin sensitivity, lower triglycerides and cholesterol, higher ATP output, and, in single-nucleus RNA sequencing of white adipose tissue, reduced expression of genes linked to the senescence-associated secretory phenotype. If a drug or supplement can activate this pathway in humans, the practical implications are large; several existing compounds (urolithin A among them) are thought to support supercomplex formation, though whether they act through COX7RP specifically is unknown. The observable signal that matters: biotech interest. Mechanistic findings like this either attract early-stage investment within a year or they don't — and that tells you which way the field is reading it.

A before-and-after thread on r/Biohackers pulled 1,425 points this week — the highest-engagement longevity signal in the trending data. GHK-Cu (glycyl-L-histidyl-L-lysine copper) is a naturally occurring tripeptide that drops from about 200 ng/ml in human plasma at age 20 to 80 ng/ml by 60, and has more than fifty years of published research behind it. It's genuinely interesting biology.

The honest evidence read: GHK-Cu has solid preclinical data across many tissues and real human evidence for topical skin and wound applications — it's already used in FDA-cleared wound healing devices. For the injectable use driving most of the Reddit enthusiasm, almost all published evidence comes from cell cultures, animal models, or topical studies. Forums describe paradoxical skin worsening at high doses (the "copper uglies"), which is anecdotal but consistent with the risk profile of moving a controlled topical into off-label systemic use. The genuinely interesting forward experiment isn't another before-and-after photo — it's whether GHK-Cu's documented gene expression effects translate to measurable epigenetic age changes in humans. That study would matter. Fourteen hundred upvotes do not.

If you want one story that captures modern aging biology, it's this: sometimes the thing wrecking a cell isn't death, it's damage. Researchers from the University of Tokyo and St. Jude, publishing in Nature Communications on April 6, found that MLKL — a protein usually associated with necroptosis, a form of programmed cell death — can age hematopoietic stem cells without triggering cell death at all.

In mice, stress activated MLKL, which briefly moved to mitochondria and damaged them. The result looked like classic blood-system aging: less regenerative capacity, fewer lymphoid cells, and the myeloid skew that tracks with frailer, less resilient immunity in older people. Removing or inactivating MLKL preserved stem-cell function and mitochondrial performance in older and stressed animals. This is the kind of mechanism that could eventually matter for immune aging, chemotherapy recovery, and infection resilience in the elderly — and it's a fresh reminder that mitochondria keep showing up as the choke point where disparate aging processes converge. The next thing to watch: whether anyone can modulate MLKL pharmacologically without breaking the useful parts of cell-death signaling, which is the field's perpetually difficult trick.

This week: GHK-Cu going viral on Reddit, Seragon Biosciences' company-funded wonder drug beating rapamycin in mice bred and housed under company conditions, and a Columbia report politely suggesting the entire field has been measuring the wrong thing for about forty years. The most honest signal of the week was two healthy adults getting IV BPC-157 and nothing happening — which is, in peptide medicine, a minor triumph.

Stay rigorous out there.

Forward this to the friend whose supplement stack just got longer than their grocery list.