Autologous Biologic Therapy for Post-COVID Conditions (“Long COVID”)

Boulder Biologics offers investigational autologous biologic procedures for selected individuals experiencing persistent symptoms following SARS-CoV-2 infection, commonly referred to as Post-COVID Conditions or Long COVID. These procedures utilize patient-derived bone marrow–based cellular and plasma components and are intended to support recovery through immunomodulatory and reparative signaling mechanisms, rather than through direct tissue replacement.

Post-COVID conditions remain an active area of scientific investigation. While no cellular therapy has been approved by the U.S. Food and Drug Administration (FDA) for Long COVID, emerging translational and early clinical literature support further study of autologous mesenchymal stromal cell–containing biologics in this context.

Biological Features of Post-COVID Conditions

Current evidence suggests that Long COVID is a heterogeneous syndrome with several recurring biological features rather than a single disease entity: (1)

1. Persistent Organ Dysfunction: Many individuals demonstrate lingering cardiopulmonary, vascular, or endothelial abnormalities following acute infection, which may manifest as:

  • Dyspnea or exercise intolerance

  • Palpitations or autonomic instability

  • Reduced diffusion capacity or imaging abnormalities

Structural damage, microvascular injury, and impaired tissue repair are thought to contribute to these symptoms. (1)

2. Immune Dysregulation and Chronic Inflammation: Long COVID is frequently associated with:

  • Persistent elevation of inflammatory cytokines (e.g., IL-6)

  • Altered T-cell and NK-cell activity

  • Features of immune exhaustion or autoinflammatory signaling

This dysregulated immune state is believed to underlie fatigue, myalgias, and systemic symptoms. (1,4-7)

3. Neurological and Cognitive Dysfunction: Recent neurobiological studies demonstrate:

  • Blood–brain barrier (BBB) disruption

  • Ongoing neuroinflammation

  • Altered glial and vascular signaling

These changes correlate with cognitive impairment (“brain fog”), headache, and autonomic symptoms seen in Long COVID. (2)

About Mesenchymal Stromal Cell–Containing Biologics

Mesenchymal stromal cells (MSCs) are non-hematopoietic cells found in bone marrow and other tissues. Importantly, current scientific consensus emphasizes that their clinical activity is primarily mediated by paracrine signaling and immune modulation, rather than by differentiation into organ-specific cells. (3,4)

Key properties described in the literature include:

  • Immunomodulation (interaction with T cells, NK cells, macrophages)

  • Anti-inflammatory signaling

  • Support of tissue repair environments

  • Endothelial and microvascular support

Claims of routine in vivo differentiation into neurons, cardiomyocytes, or other mature tissues are not supported in clinical human data and are avoided here.

Rationale for Autologous Bone Marrow–Derived Biologic Use in Long COVID

Immune System Modulation: Multiple experimental and early clinical studies suggest that MSC-containing biologics can:

  • Down-regulate pro-inflammatory cytokines

  • Increase anti-inflammatory mediators such as IL-10

  • Modulate overactive T-cell and NK-cell responses

These effects have been observed in severe acute COVID-19 and are hypothesized to be relevant to post-acute immune dysregulation. (4-7)

Tissue Repair Signaling

Rather than replacing damaged cells, MSC-derived paracrine factors may:

  • Support endothelial repair

  • Improve microvascular signaling

  • Promote a more permissive environment for endogenous tissue recovery (3,4)

Neurological Considerations and Intranasal Delivery

Preclinical and translational studies demonstrate that intranasal delivery of autologous cellular products can allow biologic signals to access the central nervous system via olfactory and trigeminal pathways, bypassing systemic circulation. (8) This route is being investigated for neurological and cognitive symptoms, though it remains investigational.

What Is Autologous Bone Marrow–Derived Biologic Therapy?

This investigational approach involves:

  1. Bone marrow aspiration from the posterior superior iliac spine (PSIS)

  2. Filtration and minimal processing of bone marrow aspirate

  3. Optional concentration of cellular components

  4. Autologous administration via:

    • Intravenous (IV) infusion

    • Intranasal atomization (in selected cases)

No donor cells, genetic modification, or culture expansion is used.

Safety Considerations

  • Autologous biologics reduce the risks of immune rejection seen with donor-derived products

  • Published studies in COVID-19 populations report acceptable short-term safety profiles, though data remain limited (4-7)

  • This approach is not risk-free, and the benefit is not guaranteed

At Boulder Biologics:

  • Only autologous materials are used

  • Patients undergo careful screening

  • Treatment is framed as investigational

Clinical Outcomes and Current Evidence

Clinical evidence for MSC-based biologics in Long COVID is preliminary. Early reports and small studies suggest possible improvement in:

  • Fatigue

  • Autonomic symptoms

  • Cognitive complaints

However:

  • Not all patients improve

  • Controlled Long COVID–specific trials are still ongoing

  • These therapies should be viewed as experimental supportive interventions, not established treatments

Regulatory Disclosure

The procedures described on this page involve autologous biologic products.

Regulatory Status and FDA Position: The U.S. Food and Drug Administration (FDA) has stated that no stem cell or cellular therapy has been approved to treat COVID-19, Long COVID, or post-COVID conditions. This includes therapies marketed for immune modulation, neurological recovery, fatigue, cardiopulmonary symptoms, or “regeneration.”

The biologic procedures described on this page involve autologous human cells and tissues and are provided as investigational medical interventions, not as FDA-approved drugs or biologics. These procedures are offered based on physician judgment, emerging scientific evidence, and individualized patient evaluation.

The FDA has specifically cautioned patients and providers about clinics that:

  • Claim stem cells can cure or reverse COVID-19 or Long COVID

  • Claim injected cells replace damaged organs or brain tissue

  • Market stem cells as “proven,” “approved,” or “guaranteed” treatments

Boulder Biologics does not make these claims.

Terminology and Scientific Accuracy: Consistent with FDA guidance and current scientific consensus:

  • We avoid claims that mesenchymal stromal cells differentiate into functional lung, heart, or brain cells in vivo.

  • We do not claim tissue regeneration, organ replacement, or cure of Long COVID.

  • Any potential benefit is described as paracrine signaling, immune modulation, and support for endogenous repair processes, consistent with the prevailing literature and FDA-accepted scientific framing.

References to “stem cells” on this page reflect cellular populations contained within autologous bone marrow–derived biologic material, not manufactured or expanded stem cell products.

Autologous vs Donor-Derived Cells: The FDA has raised particular concern regarding allogeneic (donor-derived) stem cell products, including umbilical cord, placental, and amniotic products, marketed outside of approved clinical trials.

At Boulder Biologics:

  • Only autologous (patient-derived) cellular material is used

  • No donor cells are administered

  • No culture expansion, genetic modification, or manufacturing of cells occurs

This distinction is important, as FDA enforcement actions have primarily targeted unapproved donor-derived products marketed without appropriate authorization.

Investigational Nature and Informed Consent: The FDA emphasizes that investigational cellular therapies must be presented transparently. Accordingly:

  • Patients are informed that this approach is experimental

  • Clinical response is variable and unpredictable

  • Some patients may experience no benefit

  • Long-term efficacy data for Long COVID are not yet established

Participation is voluntary, and treatment is undertaken only after a comprehensive informed consent process.

Safety Framing: While published studies in acute COVID-19 populations suggest that autologous and MSC-based cellular therapies have acceptable short-term safety profiles, the FDA cautions that:

  • “Safe” does not mean “effective”

  • Absence of short-term harm does not establish long-term benefit

  • Adverse events, including infection, thrombosis, immune effects, or lack of benefit, remain possible

For this reason, safety is discussed conservatively, and no statements of “minimal risk” or “risk-free” therapy are made.

How This Differs from Non-Compliant Stem Cell Clinics

Boulder Biologics’ approach differs from non-compliant stem cell marketing in that we:

  • Do not advertise stem cells as FDA-approved

  • Do not claim disease modification, cure, or regeneration

  • Do not use donor-derived perinatal tissues

  • Do not imply endorsement by the FDA

  • Do not claim universal effectiveness

This page is intended to inform, not to promote unproven claims.

FDA Consumer Guidance (for patient reference): The FDA encourages patients considering cellular therapies to:

  • Ask whether a treatment is FDA-approved

  • Be skeptical of claims that sound “too good to be true”

  • Understand the difference between clinical research and established therapy

Patients are encouraged to review FDA consumer resources on regenerative medicine and stem cell therapies.

References

1.     Centers for Disease Control and Prevention. Post-COVID Conditions. https://www.cdc.gov/coronavirus/2019-ncov/long-term-effects/index.html

2.     Greene C, Connolly R, Brennan D, et al. Blood–brain barrier disruption and sustained systemic inflammation in individuals with long COVID–associated cognitive impairment. Nature Neuroscience. 2024;27:421–432. https://doi.org/10.1038/s41593-024-01576-9

3.     Mesenchymal Stem Cell – Overview. ScienceDirect Topics.

https://www.sciencedirect.com/topics/engineering/mesenchymal-stem-cell

4.     Shi L, Wang L, Xu R, et al. Mesenchymal stem cell therapy for severe COVID-19.

Signal Transduction and Targeted Therapy. 2021;6:339. https://doi.org/10.1038/s41392-021-00754-6

5.     Leng Z, Zhu R, Hou W, et al. Transplantation of ACE2- mesenchymal stem cells improves the outcome of patients with COVID-19 pneumonia. Aging and Disease. 2020;11(2):216–228. PMID:32257537

6.     Song N, Wakao S, Hanibuchi M, et al. Mesenchymal stem cell immunomodulation in COVID-19–related cytokine storm. Stem Cells. 2021. https://doi.org/10.1002/stem.3354

7.     Beghini DG, Horita SI, Henriques-Pons A. Mesenchymal stem cells in the treatment of COVID-19. Cells. 2021;10(10):2588. https://doi.org/10.3390/cells10102588

8.     Galeano C, Qiu Z, Mishra A, et al. The route by which intranasally delivered stem cells enter the central nervous system. Cell Transplantation. 2018;27(3):501–514. https://doi.org/10.1177/0963689718754561