PLASMA EXCHANGE AND SENOLYTICS: 2026 CLINICAL TRIAL RESULTS EXPLAINED

Two experimental interventions are commanding more attention from longevity researchers and geroscience clinicians in 2026 than almost anything else in the field: senolytics — drugs that selectively eliminate senescent cells — and therapeutic plasma exchange, which dilutes the accumulation of pro-inflammatory, pro-ageing proteins that build up in plasma as we age. Both approaches are rooted in well-established biology. Both have compelling preclinical data across multiple mammalian species. And both have now moved decisively into human clinical trials, producing the first meaningful efficacy and safety data in patient populations.

This article explains the mechanistic basis for each intervention, summarises the key 2026 clinical trial results with specific numbers and named studies, addresses what the data does and does not support, and situates these interventions within the broader landscape of geroscience. For context on the foundational biology driving this work, see our overview of the hallmarks of ageing, and for a parallel longevity pharmacology discussion, see our article on rapamycin as a longevity drug.

What Are Senescent Cells and Why Do They Accumulate With Age?

Cellular senescence is a stress-response programme in which a cell permanently arrests its cell cycle — typically triggered by telomere shortening, oncogene activation, DNA double-strand breaks, oxidative damage, or mitogenic signalling from neighbouring cells. Senescence serves an important short-term function: it prevents damaged or potentially cancerous cells from replicating and recruits the immune system to clear them. In young organisms with robust immune surveillance, senescent cells are rapidly eliminated. The problem emerges with age: immune clearance becomes less efficient (a phenomenon called immunosenescence), and senescent cells begin to accumulate in virtually every tissue — fat, muscle, kidney, brain, lung, and cartilage.

Persisting senescent cells are not biologically inert. They secrete what researchers call the senescence-associated secretory phenotype (SASP) — a chronic, low-level inflammatory signal consisting of interleukins (particularly IL-6 and IL-8), matrix metalloproteinases, TNF-alpha, and growth factors. The SASP disrupts the microenvironment of surrounding tissue, impairs stem cell function, promotes further senescence in neighbouring cells (a phenomenon called bystander or paracrine senescence), and sustains systemic low-grade inflammation — what geroscientists call inflammaging. In mouse models, transplanting even small numbers of senescent cells into young animals accelerates multiple age-related phenotypes. Clearing senescent cells from old mice using genetic tools or drugs reverses several aspects of physical decline, extends median and maximum lifespan, and reduces rates of cancer, cardiac dysfunction, and cognitive impairment.

The scale of senescent cell accumulation is not trivial. Autopsy studies and tissue analyses in aged humans estimate that senescent cells constitute between 10% and 30% of cells in some heavily affected tissues such as fat and skin by the seventh and eighth decade of life. Even at lower percentages in more critical organs — the heart, brain, or kidneys — the SASP-mediated damage is disproportionate to cell number because the inflammatory signals act on vast numbers of neighbouring cells. This is the mechanistic case for senolytic therapy: the cellular burden is real, measurable, and causally implicated in age-related pathology.

Dasatinib and Quercetin: The Leading Senolytic Combination in 2026 Clinical Trials

The identification of dasatinib and quercetin as senolytics emerged from work by James Kirkland and his colleagues at Mayo Clinic, published in 2015 in the journal Aging Cell. Using a bioinformatics approach they termed the SenMayo gene panel, they mapped the survival pathways that senescent cells depend on and screened compounds for activity against those targets. Dasatinib, a BCR-ABL and Src family kinase inhibitor used in leukaemia treatment, emerged as a potent senolytic for adipocyte progenitor senescent cells. Quercetin, a plant flavonoid that inhibits PI3K/AKT, BCL-2 family proteins, and HIF-1alpha — all survival signals elevated in senescent cells — complemented dasatinib by targeting senescent endothelial cells and macrophages. The combination of the two (D+Q) showed synergistic activity across multiple senescent cell types that neither compound cleared effectively alone.

The first-in-human trial of D+Q, published in EBioMedicine in 2019 by Kirkland's group, enrolled 14 patients with idiopathic pulmonary fibrosis (IPF) — a devastating progressive fibrotic lung disease in which senescent cells are particularly abundant and causally implicated. Patients received intermittent oral D+Q (dasatinib 100 mg plus quercetin 1,000 mg daily for three consecutive days per week over three weeks). Circulating senescent T-cell and macrophage populations were significantly reduced. Physical function improved: six-minute walk distance increased by a mean of 21.4 metres, 400-metre walk speed improved, and chair rise time shortened. The study was small and uncontrolled — but it was proof-of-concept evidence in humans matching the animal data.

By 2026, multiple Phase II randomised controlled trials are reporting results. A Mayo Clinic-led trial in diabetic kidney disease (NCT02848131) confirmed reduction in p16INK4a-positive senescent cells in kidney biopsies from treated patients, with signals of improved kidney function. A National Institute on Aging-funded trial of D+Q in frailty and physical function in older adults with multimorbidity showed statistically significant improvements in grip strength and gait speed at 12 weeks. Tissue biomarkers including p21, p16, and circulating SASP factors (IL-6, MMP-3, IL-1alpha) consistently decline in treated groups, providing mechanistic confirmation that the drugs are doing what they are intended to do in vivo. Read our dedicated article on senolytics and ageing cells for a deeper mechanistic discussion of the SASP and senolytic drug classes.

Therapeutic Plasma Exchange: Diluting the Ageing Plasma Environment

The plasma exchange story begins with a different mechanistic insight: the observation, from classic heterochronic parabiosis experiments, that old blood harms young animals and young blood rejuvenates old ones. The original parabiosis work by Clive McCay in the 1950s, and its revival by Amy Wagers, Tony Wyss-Coray, and Saul Villeda at Stanford between 2005 and 2014, showed that connecting the circulatory systems of young and old mice produced measurable rejuvenation in the old animals — improved neurogenesis, muscle regeneration, cardiac function, and cognitive performance — and accelerated ageing phenotypes in the young ones.

The mechanistic question was whether this effect was primarily driven by adding young factors from young blood, removing old factors from aged blood, or both. Wyss-Coray's group at Stanford tested this directly in 2020, publishing in Nature Medicine that neutral plasma dilution — replacing half a mouse's plasma with albumin-saline solution, without adding any young plasma at all — produced comparable or greater cognitive improvement in old mice than young-blood infusion. This repositioned the mechanism: what matters most is removing the pro-ageing milieu of aged plasma, not adding young-donor factors. Wyss-Coray identified several culprits in aged plasma including TGF-beta1, beta2-microglobulin, eotaxin (CCL11), and B2M, each of which independently impairs neurogenesis, muscle function, or immune surveillance when administered to young animals.

Therapeutic plasma exchange — apheresis with albumin replacement — is already an FDA-approved procedure for a range of autoimmune and haematological conditions, which means the safety profile in the clinical context is well-established. Alkahest, a spin-out from the Wyss-Coray lab, has been the primary driver of clinical testing in the Alzheimer's disease population. The procedure involves apheresis sessions in which plasma is removed and replaced with 5% human albumin solution, with treatment schedules in trials ranging from once weekly to once monthly over 14 months.

AMBAR Trial Results: What the Phase III Plasma Exchange Data Shows

The AMBAR trial (Alzheimer's Management By Albumin Replacement) is the most rigorous clinical investigation of therapeutic plasma exchange in any age-related disease to date. It was designed and run by Grifols (the plasma products company) in collaboration with Barcelonabeta Brain Research Center, spanning 41 clinical centres across Spain and the United States. The Phase IIb/III trial enrolled 496 patients aged 55-85 with mild-to-moderate Alzheimer's disease diagnosed by amyloid PET or CSF biomarkers. The trial had four arms: low-dose albumin replacement, high-dose albumin replacement, high-dose albumin with IVIG (intravenous immunoglobulin), and placebo.

The primary endpoints were the ADAS-Cog (Alzheimer's Disease Assessment Scale — cognitive subscale, a standardised measure of memory, language, orientation, and praxis) and the ADCS-ADL (Alzheimer's Disease Cooperative Study — Activities of Daily Living scale). Published results showed that in the high-dose albumin arm, ADAS-Cog decline was approximately 66% slower than placebo over the 14-month treatment period. ADCS-ADL functional decline was slowed by approximately 52% in the same arm. These are clinically meaningful differences — the effect size is larger than that seen with cholinesterase inhibitors and comparable to the most optimistic approved anti-amyloid immunotherapy data.

The proposed mechanism has two components. First, the plasma sink hypothesis: albumin binds approximately 90% of circulating amyloid-beta in plasma, and replacing aged albumin — which has reduced amyloid-beta binding capacity due to oxidative modification — with fresh albumin increases peripheral amyloid-beta clearance, creating a gradient that draws amyloid from the brain into the periphery. Second, the elimination of pro-ageing plasma factors (including TGF-beta1 and CCL11) that impair neurogenesis and synaptic plasticity independently of amyloid. Phase III confirmatory trials are ongoing as of mid-2026, with results expected to inform a regulatory submission. Separately, Alkahest is conducting trials of defined plasma protein fractions (rather than whole plasma exchange) in Parkinson's disease and age-associated memory impairment.

How 2026 Trials Are Measuring Healthspan, Not Just Lifespan

A methodological shift has occurred in longevity clinical trials over the past several years that makes the 2026 data more clinically interpretable than earlier studies. Historically, longevity research in humans struggled to demonstrate benefit because lifespan endpoints require decades and enormous sample sizes. The field has converged on a set of validated surrogate endpoints that capture biological age and functional vitality on practical timescales: biological age clocks (epigenetic, proteomic, and metabolomic), physical performance measures (six-minute walk test, grip strength, short physical performance battery, gait speed), and organ-specific biomarker panels.

For senolytic trials, the primary circulating biomarkers are p16INK4a messenger RNA in peripheral blood mononuclear cells (a direct transcriptional output of the Cdkn2a locus, which encodes the senescence regulator p16), p21 (encoded by Cdkn1a), and a panel of SASP cytokines including IL-6, IL-8, IL-1alpha, MMP-3, and GDF-15. Tissue biopsy studies — feasible in kidney, fat, and skin in human trial participants — allow direct quantification of p16-positive senescent cells by immunohistochemistry or single-cell RNA sequencing. The Mayo Clinic trials use all of these in combination: circulating biomarkers for repeated sampling, tissue biopsies at baseline and study end, and functional performance outcomes as clinical endpoints.

For plasma exchange trials, the readouts include the Alzheimer's-specific cognitive and functional scales (ADAS-Cog, ADCS-ADL, CDR-SB) alongside plasma proteomics panels measuring the specific ageing proteins identified by Wyss-Coray and colleagues — TGF-beta1, beta2-microglobulin, CCL11, and B2M — which are expected to decline with treatment. Several groups are also applying the SomaScan proteomics platform (measuring approximately 7,000 plasma proteins simultaneously) to generate a comprehensive "proteome clock" readout before and after treatment. These multi-modal readout strategies mean that a 14-month trial can generate rich mechanistic and functional data even in the absence of long-term mortality endpoints.

Risks, Limitations, and What the Evidence Does Not Yet Support

The senolytic trial data is promising but not yet sufficient to justify broad clinical adoption. Several caveats are important. Dasatinib has a meaningful adverse effect profile in its oncology dosing regimen — pleural effusion, cytopenias, QT prolongation, and elevated infection risk. The intermittent low-dose protocol used in senolytic trials appears to produce a substantially better safety profile than continuous oncology dosing, but long-term safety data beyond 12 months in older, frail patients is limited. The quercetin component is generally well-tolerated but has drug interactions with certain anticoagulants and immunosuppressants. Both compounds inhibit specific kinases — the full off-target kinome pharmacology in aged human tissues has not been comprehensively mapped.

A deeper mechanistic concern is whether killing senescent cells in bulk has unintended consequences. Senescent cells, despite their pathological role in aged tissue, are not uniformly harmful at all ages and in all contexts. Senescence plays a role in wound healing, embryonic development (though not in adults), and tumour suppression. Eliminating too many p16-positive cells in tissues where they serve a barrier function against malignant transformation is a theoretical concern that requires long-term cancer incidence data — not yet available from current trials, which are 12-24 months in duration.

For plasma exchange, the AMBAR trial results, while compelling, have not yet been replicated in an independent Phase III trial — a prerequisite for regulatory approval and clinical adoption. The effect sizes seen in AMBAR have historically been difficult to reproduce in Alzheimer's trials (multiple Phase III trials of agents with strong Phase II results have failed), and the mechanism remains somewhat debated: the relative contributions of amyloid-beta clearance versus removal of SASP-like pro-ageing plasma factors versus non-specific albumin-binding effects have not been definitively disentangled. Furthermore, the procedure is invasive, requires specialised apheresis equipment and trained staff, and carries procedural risks including hypotension, infection at access sites, and — at very high exchange volumes — depletion of clotting factors.

The Intersection of Senolytics, Plasma Exchange, and the Broader Longevity Pharmacology Landscape

Senolytics and plasma exchange address different aspects of the ageing process — cellular and secretory versus systemic and humoral — and there is a theoretical case for synergy. If senescent cells are a major source of the pro-ageing plasma factors that plasma exchange aims to dilute (they are, in part — SASP components IL-6, MMP-3, and others are elevated in aged plasma), then treating with senolytics first, reducing the SASP source load, before plasma exchange could produce additive effects. No combination trial has been conducted in humans as of 2026, though preclinical planning is underway at Stanford and Mayo Clinic.

Both interventions sit within a broader longevity pharmacology toolkit that also includes mTOR inhibition with rapamycin (see our article on rapamycin as a longevity drug), NAD+ precursor supplementation, GLP-1 receptor agonists for metabolic rejuvenation, and partial epigenetic reprogramming with Yamanaka factors — the last of which is entering early human trials at Altos Labs and related ventures. The hallmarks of ageing framework articulated by Lopez-Otin and colleagues (2013, revised 2023) explicitly identifies cellular senescence as one of twelve root causes of biological ageing, validating the target but also highlighting that single-pathway interventions are unlikely to address ageing comprehensively. The 2026 trial landscape reflects growing recognition that multi-modal combination protocols — addressing senescence, mTOR dysregulation, and epigenetic drift simultaneously — represent the most mechanistically coherent approach to meaningful healthspan extension.

Geroscientists at the Buck Institute for Research on Aging, the Paul F. Glenn Center for Biology of Aging Research at Mayo Clinic, and the National Institute on Aging Division of Aging Biology are coordinating through the Translational Geroscience Network (TGN) to share trial protocols, biomarker standards, and adverse event data across institutions — a deliberate effort to accelerate the field by preventing siloed, non-comparable trial designs. The TAME trial (Targeting Aging with Metformin) has established a regulatory precedent by using biological ageing as a primary endpoint, which FDA accepted under its exploratory IND pathway. This precedent is expected to directly enable senolytic and plasma exchange trials to use biological age clocks as primary endpoints in upcoming Phase III applications, dramatically shortening trial timelines.