Impact of Lp299v on Vascular Function in Patients With PASC

Study Overview
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Brief Summary
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Emerging data show that SARS-CoV-2 infection causes gut microbiome changes strongly associated with Post-Acute Sequelae of SARS-CoV-2 (PASC). The investigators and others have established that an orally ingested probiotic (Lactobacillus plantarum 299v, Lp299v) reduces circulating levels of cell-free mitochondrial DNA (cf-mtDNA), decreases toll-like receptor 9 (TLR9) activation [and downstream interleukin (IL-6)], and improves micro- and macrovascular (brachial artery) endothelial dysfunction [as measured by flow-mediated dilation (FMD%)] in humans. Recently published data also report impaired brachial FMD% and increased vascular stiffness post-SARS-CoV-2 infection. Based on these data, the investigators hypothesize that supplementation with Lp299v will attenuate SARS-CoV-2 associated endothelial dysfunction by reducing cf-mtDNA, TLR9 activation, and inflammation.

Detailed Description
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The intestinal immune system plays a critical role in systemic immunity, and its interaction with the systemic immune system plays a crucial role in determining the severity and outcomes of common pulmonary infections. SARS-CoV-2 infection alters the composition and metabolism of the gut microbiome. Greater losses of beneficial species in the human gut microbiome of SARS-CoV-2 patients are associated with severe disease and greater systemic inflammation. These pathological alterations are observed at least 6 months post-infection and are associated with greater residual systemic inflammation and PASC symptoms. Six weeks of Lp299v supplementation in otherwise healthy smokers reduces circulating levels of the pro-inflammatory IL-6 and reduces monocyte adhesion to endothelial cells. IL-6 is elevated in patients with PASC and strongly correlates with TLR9 activation in disease states with high circulating cf-mtDNA levels. We published trial data showing once daily Lp299v supplementation (20 billion colony forming units/day) in men with coronary artery disease (CAD) improves endothelium-dependent vasodilation in the brachial artery and NO-dependent vasodilation of resistance arterioles from CAD patients. Further, preliminary data suggest Lp299v reduces circulating levels of cf-mtDNA (Fig. 2B). We also published data showing that 6 weeks of Lp299v has a significant anti-inflammatory effect on PBMC gene transcription, with gene ontology analyses indicating Lp299v supplementation inhibits TLR9 activation (z-score -3.48, P<0.0000000023). Combining the evidence that Lp299v reduces (1) circulating cf-mtDNA; (2) TLR9 activation; and (3) IL-6 levels while improving micro- and macrovascular endothelial function make Lp299v an excellent candidate to test as an intervention to improve vascular function in PASC patients. Therefore, we will recruit subjects ages ≥18-89 who carry a clinical diagnosis of PASC and are within a window of 30-180-day post-acute symptom resolution into an 8-week, double-blind, randomized, placebo-controlled clinical trial of Lp299v supplementation. Measurements of micro- and macrovascular function, systemic inflammation, and stool microbiota composition will be made.

Official Title
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Impact of Lp299v on Vascular Function in Patients With PASC

Conditions
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COVID-19

Intervention / Treatment
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* Other: Lactobacillus Plantarum 299v Freeze Dried Capsule
* Other: Freeze Dried Potato Starch Capsule


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ages 18 to 89 years 30-180 days post-COVID-19 diagnosis PASC diagnosed based on symptom report/expert physician judgement Exclusion Criteria: Antibiotics within four weeks of enrollment History of chronic diseases (renal insufficiency, liver dysfunction, cancer requiring systemic treatment within 3 years of enrollment) History of cognitive impairment/inability to follow study procedures Short gut syndrome, inflammatory bowel disease, or an ileostomy. Subjects currently taking Vitamin K antagonists such as coumadin or warfarin Pregnant at the time of screening Unstable coronary artery disease (new symptoms or event within 30 days of enrollment) Daily alcohol use (may interfere with Lp299v's action)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 89 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lp299v<br>Subjects will consume 20 billion colony forming units of Lp299v (2 capsules) once daily for 8 weeks. | Other: Lactobacillus Plantarum 299v Freeze Dried Capsule<br>* The intervention is a probiotic lactobacillus that is contained in food products in the US<br>|
| Placebo Comparator: Heat-killed placebo control<br>Subjects will consume potato starch (2 capsules) once daily for 8 weeks. | Other: Freeze Dried Potato Starch Capsule<br>* The intervention is potato starch that is freeze dried designed to mimic the lp299v capsule.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brachial Artery Flow Mediated Dilation (FMD%) | This is a measurement of endothelial function in the brachial artery | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Nitroglycerin-Mediated Vasodilation of the brachial artery (NMD) | Measurement of vascular smooth muscle reactivity | 8 weeks | 
| Hyperemic Flow Velocity | Measurement of microvascular endothelial function | 8 weeks | 
| Carotid-Femoral Pulse Wave Velocity (cfPWV) | Measurement of vascular stiffness | 8 weeks | 
| Percentage of Laser Doppler Signal | Measurement of skin microvascular function | 8 weeks | 
| interleukin-6 | circulating inflammatory marker | 8 weeks | 
| Stool microbiota alpha diversity | Diversity of bacterial species in the individual microbiome | 8 weeks | 
| Stool microbiota beta diversity | Differences in bacterial composition between intervention arms | 8 weeks | 
| Cell-Free Mitochondrial DNA (cf-mtDNA) | Level of circulating cf-mtDNA in the plasma | 8 weeks | 
| Brachial Artery Resting Diameter | resting diameter of the brachial artery - representative of resting vascular tone | 8 weeks | 
| Myeloid Cell Population phenotypes | Quantification and identification of mononuclear cell and neutrophil types | 8 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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endothelial function, PASC, COVID-19, inflammation, microbiome