# Therapeutic plasma exchange

Rating: Promising — Some human trials, or consistent animal work with a clear mechanism
Type: Therapy
Updated: 2026-10-15
Canonical: https://heretic.bio/articles/therapeutic-plasma-exchange-tpe.html

> Therapeutic plasma exchange removes plasma containing pro-aging factors and replaces it with albumin or donor products. It is an established, FDA-cleared treatment for conditions like Guillain-Barre and TTP; for longevity, the evidence is one 2025 randomized placebo-controlled trial (n=44) in which TPE plus IVIG cut composite biological age by 2.6 years across 36 epigenetic clocks. Effects waned within months, the trial had no IVIG-only arm, and sicker participants benefited most. Long-term safety of repeated use is unknown.

> **Core thesis:** Therapeutic plasma exchange (TPE) removes a person's blood plasma — which accumulates pro-aging inflammatory factors, senescence-associated secretory phenotype (SASP) proteins, and other deleterious molecules with age — and replaces it with albumin/saline or donor plasma. Grounded in decades of heterochronic parabiosis research showing that young blood rejuvenates old tissues, TPE is now being tested as a longevity intervention. The first human clinical trial (Fuentealba et al., _Aging Cell_ , 2025) demonstrated that TPE combined with IV immunoglobulin (IVIG) reduced biological age by an average of 2.6 years as measured by 36 epigenetic clocks and multi-omic biomarkers. This is an experimental therapy with real risks and limited long-term data.

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## Theoretical Foundation: Young Blood, Old Blood

### Heterochronic Parabiosis

The conceptual basis for TPE in longevity comes from **heterochronic parabiosis** — surgically connecting the circulatory systems of a young and old mouse so they share blood.

Study | Key Finding | Significance  
---|---|---  
**Conboy et al. 2005** (_Nature_) | Exposure of old mice to young blood rejuvenated aged progenitor cells in liver, skeletal muscle | Revived the field; proved systemic factors drive aging  
**Villeda et al. 2011** (_Nature_) | Old blood impaired neurogenesis and cognition in young mice | Showed old blood contains pro-aging factors  
**Rebo et al. 2016** (_Nature Communications_) | Neutral blood exchange (not full parabiosis) improved multiple tissues in old mice | Demonstrated plasma itself, not cells, drives effect  
**Sviercovich et al. 2024** (_Ageing Research Reviews_) | Old blood has age-related increase in protein production and "noise" | Identified proteostasis disruption as mechanism  
  
### The "Old Blood" Hypothesis

The current model is that aging blood plasma accumulates: \- **SASP proteins** from senescent cells (pro-inflammatory cytokines: IL-6, TNF-α, TGF-β) \- **Pro-aging signaling molecules** (CCL11/eotaxin, β2-microglobulin) \- **Inflammatory mediators** driving inflammaging \- **Microplastics and environmental toxins** (removed by TPE) \- **Degraded extracellular matrix fragments**

TPE removes these circulating factors, diluting the pro-aging systemic milieu. Unlike parabiosis, TPE does not add "young" factors — it purely dilutes old ones, suggesting that **removal of deleterious factors may be more important than addition of beneficial ones**.

> **Key insight:** The Conboy lab argues that the rejuvenating effect of young blood in parabiosis is actually due to **dilution of old blood factors** , not transfer of young factors. Their neutral blood exchange experiments support this — old mice improved just from having their plasma replaced with saline/albumin.

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## The First Human Trial: Circulate Health / Buck Institute

### Fuentealba et al. 2025 (_Aging Cell_)

This is the landmark study — the **first randomized, single-blind, placebo-controlled trial** of TPE for biological aging in humans.

**Citation:** Fuentealba M, Kiprov D, Schneider K, et al. "Multi-omics analysis reveals biomarkers that contribute to biological age rejuvenation in response to single-blinded randomized placebo-controlled therapeutic plasma exchange." _Aging Cell_. 2025;24(7):e70103. doi:[10.1111/acel.70103](https://doi.org/10.1111/acel.70103)

#### Study Design

  * **Participants:** 44 adults completed the study (average age in their 60s)
  * **Design:** Single-blind, placebo-controlled, randomized
  * **Groups:** 1\. Weekly TPE for 6 months 2\. Biweekly TPE for 3 months 3\. Biweekly TPE + IVIG for 3 months 4\. Sham/placebo group
  * **Measurements:** 36 epigenetic clocks (including GrimAge, Horvath, Hannum, DamAge), proteomics, metabolomics, immune cell phenotyping



#### Key Results

Metric | TPE + IVIG Group | Weekly TPE Group | Sham Group  
---|---|---|---  
**Biological age reduction (composite)** | **−2.61 years** | −1.32 years | Worsened  
**Immune profile** | T cells, NK cells, monocytes shifted toward youthful profile | Moderate changes | Aged  
**Proteomic rejuvenation** | Strongest (proteostasis, senescence, inflammaging markers) | Moderate | —  
**Durability** | Benefit diminished by time point 3 (2 months post-treatment) | Similar waning | —  
  
#### Critical Observations

  1. **IVIG may be the active ingredient:** The study lacked an IVIG-only arm, making it impossible to determine if IVIG or TPE was driving the effect. The IVIG component may be more potent than the plasma exchange itself.
  2. **Benefits were transient:** Effects were strongest at the first post-treatment time point and diminished at the second, suggesting "potential compensatory mechanisms that mitigate the anti-aging effects after multiple sessions."
  3. **Sicker patients responded more:** Participants in poorer health (measured by monocyte and platelet levels) were stronger responders. Healthy individuals showed minimal benefit.
  4. **Baseline variability:** Different clocks showed different baselines across groups, complicating interpretation.
  5. **Small sample size:** N=44 across 4 groups means ~11 per group — underpowered for robust statistical conclusions after correction for 36 clocks.



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## Mechanism of Action

### How TPE Works Mechanically

TPE (also called plasmapheresis) is an FDA-cleared medical procedure: 1\. Blood is withdrawn from the patient 2\. A centrifuge or membrane separator separates plasma from cellular components (RBCs, WBCs, platelets) 3\. Plasma is discarded 4\. Cellular components are returned to the patient mixed with replacement fluid (5% albumin in saline, or donor plasma/IVIG) 5\. Process removes approximately 1.0–1.5 plasma volumes per session

### What TPE Removes

Factor Category | Examples | Aging Relevance  
---|---|---  
**SASP proteins** | IL-6, IL-8, TNF-α, TGF-β, MMPs | Drive inflammaging, tissue degradation  
**Autoantibodies** | ANA, anti-citrullinated protein | Increase with age, drive autoimmunity  
**Pro-aging peptides** | CCL11/eotaxin, β2-microglobulin | Impair neurogenesis, cognitive function  
**Lipotoxic factors** | Oxidized LDL, ceramides | Drive metabolic dysfunction  
**Environmental toxins** | Microplastics, PFAS, heavy metals | Accumulate over decades  
**Inflammatory mediators** | CRP, complement proteins | Chronic low-grade inflammation  
  
### IVIG Mechanism (If Combined)

IV immunoglobulin (IVIG) is a pooled preparation of IgG from thousands of donors: \- Provides **natural antibodies** against senescent cell surface markers \- **Immunomodulatory** effects: regulates Fc receptors, neutralizes autoantibodies \- May accelerate clearance of senescent cells via antibody-dependent cellular cytotoxicity (ADCC) \- Contains **anti-idiotypic antibodies** that suppress autoimmune responses

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## Doses in studies

### Standard Medical TPE (Established)

  * **Volume exchanged:** 1.0–1.5 plasma volumes (~3L for average adult)
  * **Duration:** 1.5–2 hours per session
  * **Replacement fluid:** 5% albumin in normal saline (standard) or fresh frozen plasma
  * **Frequency:** Typically 1–3 sessions per week for acute conditions
  * **Access:** Large-bore peripheral IV or central venous catheter
  * **Anticoagulation:** Citrate (ACD-A) during procedure



### Doses in studies

  * **Frequency options:**
  * Weekly for 6 months (less intensive)
  * Biweekly (2x/week) for 3 months (more intensive)
  * **IVIG addition:** 1–2 g/kg IVIG after select TPE sessions
  * **Monitoring:** Epigenetic clocks (Horvath, GrimAge), immune panels, proteomics before/after
  * **Maintenance:** Unknown; no established re-treatment interval



> ⚠️ **Important:** No established longevity TPE protocol exists. All current protocols are experimental. The Circulate Health trial design is the closest to evidence-based.

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## Clinical Applications Beyond Longevity

TPE is FDA-approved and well-established for numerous conditions:

### FDA-Approved Indications (ASFA Category I)

  * **Guillain-Barré syndrome** — acute inflammatory demyelinating polyneuropathy
  * **Myasthenia gravis** — autoimmune neuromuscular crisis
  * **Hyperviscosity syndrome** — Waldenström's macroglobulinemia
  * **Thrombotic thrombocytopenic purpura (TTP)**
  * **Goodpasture syndrome** — anti-GBM disease
  * **Cryoglobulinemia**
  * **Severe rheumatoid arthritis** (refractory)
  * **Long COVID** (emerging evidence)



### Potential Longevity-Spanning Applications

Application | Evidence Level | Mechanism  
---|---|---  
**Biological age reduction** | Emerging (1 RCT) | Removal of SASP/inflammatory factors  
**Autoimmune disease** | Strong (approved use) | Removal of autoantibodies  
**Neurodegenerative disease** | Investigational | Reduction of neuroinflammatory factors  
**Chronic inflammation** | Investigational | CRP/cytokine reduction  
**Post-COVID syndrome** | Emerging | Removal of spike protein, inflammatory mediators  
  
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## Risks and Side Effects

### Common (5-20%)

  * **Hypocalcemia** — citrate anticoagulant binds calcium; causes perioral tingling, paresthesias
  * **Hypotension** — volume shifts during procedure
  * **Allergic reaction** — to replacement fluid (albumin, IVIG)
  * **Access complications** — hematoma, infection at IV site



### Less Common (1-5%)

  * **Infection** — related to IV access or immunosuppression from IVIG
  * **Hypogammaglobulinemia** — repeated TPE depletes immunoglobulins (rationale for IVIG replacement)
  * **Bleeding** — depletion of clotting factors (especially with albumin replacement vs. FFP)
  * **Transfusion reactions** — if donor plasma used



### Rare but Serious (<1%)

  * **Anaphylaxis** — to IVIG or replacement fluid
  * **Cardiac arrhythmia** — electrolyte disturbances
  * **Vascular injury** — central line placement complications
  * **Hypersensitivity reactions** — including ACE inhibitor-induced bradykinin-mediated reactions



### Long-Term Repeated TPE Concerns

  * **Protein depletion** — albumin, immunoglobulins, clotting factors
  * **Iron deficiency** — small RBC loss with each procedure
  * **Fibrinogen depletion** — bleeding risk
  * **Unknown long-term effects** of chronic plasma renewal on homeostasis



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## Companies and Clinical Landscape

Entity | Approach | Status  
---|---|---  
**Circulate Health** | TPE + IVIG for longevity; FDA-cleared technology | Clinical-stage; first RCT published 2025  
**Buck Institute** | Academic collaborator on multi-omics analysis | Published landmark 2025 study  
**Private clinics** | Off-label TPE protocols (various) | Unregulated; quality varies widely  
**Conboy Lab (UC Berkeley)** | Basic science; neutral blood exchange research | Preclinical; developing small-molecule alternatives  
  
### Regulatory Status

  * TPE procedure: **FDA-cleared** medical device (for specific indications)
  * Longevity use: **Off-label / experimental** — not FDA-approved for anti-aging
  * IVIG: FDA-approved for immunodeficiency, off-label for longevity
  * **Right-to-try laws** (Montana 2025, others) may expand access to experimental protocols



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## Cost and Accessibility

  * **Per TPE session:** $1,500–$3,000 (US clinic prices)
  * **Typical longevity course:** 12–24 sessions → $18,000–$72,000
  * **IVIG cost:** $7,000–$15,000 per dose (adds significantly)
  * **Insurance:** Does not cover longevity/off-label use
  * **Access:** Requires specialized clinic with apheresis equipment and medical supervision



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## Evidence Quality Summary

Evidence Type | Status | Rating  
---|---|---  
**Heterochronic parabiosis (animal)** | Multiple labs, decades of data | **Strong**  
**Neutral blood exchange (animal)** | Conboy lab, multiple studies | **Moderate-Strong**  
**TPE for medical conditions (human)** | FDA-approved, extensive RCTs | **Strong** (for approved uses)  
**TPE for longevity (human)** | 1 RCT (N=44), 2025 | **Emerging**  
**TPE + IVIG biological age reduction** | 1 RCT, significant but transient | **Preliminary**  
**Long-term safety of repeated TPE** | No data | **Unknown**  
  
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## Open Questions and Limitations

  1. **Is TPE alone effective, or is IVIG the active ingredient?** The 2025 trial had no IVIG-only arm — this is a critical gap.
  2. **How durable are the effects?** Benefits waned within months. What is the optimal re-treatment interval?
  3. **Who benefits most?** Sicker patients responded better in the trial — is TPE appropriate for healthy individuals?
  4. **What is being removed vs. what should be removed?** Multi-omics identified biomarkers but the specific causal agents of aging in plasma remain unclear.
  5. **Can oral small-molecule alternatives replicate TPE?** The Conboy lab is investigating compounds that neutralize pro-aging plasma factors without apheresis.
  6. **Safety of decades-long repeated TPE?** No longitudinal data exists for chronic use.



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## Comparison with Other Rejuvenation Approaches

Approach | Mechanism | Human Evidence | Cost | Accessibility  
---|---|---|---|---  
**TPE + IVIG** | Removes circulating pro-aging factors | 1 RCT (2025) | Very high | Low (specialized clinics)  
**[Senolytics](senolytics.html)** | Kills senescent cells | Multiple early RCTs | Low-Moderate | High (oral)  
**NAD+ precursors** | Restores NAD+ levels | Multiple RCTs | Low | High (oral)  
**Rapamycin** | mTOR inhibition | Clinical trials ongoing | Low | Moderate (prescription)  
**Young plasma infusion** | Adds young factors | Ambrosia trial (controversial, halted) | Very high | Very low  
  
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## Sources

1. Fuentealba M, Kiprov D, Schneider K, et al. Multi-omics analysis reveals biomarkers that contribute to biological age rejuvenation in response to single-blinded randomized placebo-controlled therapeutic plasma exchange. Aging Cell . 2025;24(7):e70103. doi: 10.1111/acel.70103 (DOI 10.1111/acel.70103)
2. Conboy IM, Conboy MJ, Wagers AJ, et al. Rejuvenation of aged progenitor cells by exposure to a young systemic environment. Nature . 2005;433(7027):760-764. PMID: 15716955 (PubMed 15716955)
3. Villeda SA, Luo J, Mosher KI, et al. The ageing systemic milieu negatively regulates neurogenesis and cognitive function. Nature . 2011;477(7362):90-94. PMID: 21886162 (PubMed 21886162)
4. Rebo J, Mehdipour M, Gathwala R, et al. A single heterochronic blood exchange reveals rapid inhibition of multiple tissues by old blood. Nat Commun . 2016;7:13363. PMID: 27845773 (PubMed 27845773)
5. Sviercovich A, Mei X, Xie G, Conboy MJ, Conboy IM. The dominance of old blood, and age-related increase in protein production and noise. Ageing Research Reviews . 2024;101:102641. doi: 10.1016/j.arr.2024.102641 (DOI 10.1016/j.arr.2024.102641)
6. Chen C, et al. Small extracellular vesicles from young plasma reverse age-related functional declines by improving mitochondrial energy metabolism. Nat Aging . 2024. doi: 10.1038/s43587-024-00612-4 (DOI 10.1038/s43587-024-00612-4)