Current Takeaway
Clinical management of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID currently relies on the off-label repurposing of drugs and supplements targeting suspected pathological mechanisms. Key areas of investigation focus on resolving autonomic dysfunction (preload failure), restoring mitochondrial bioenergetics, correcting chronic neuroinflammation, and clearing persistent post-viral reservoirs. A growing body of clinical trial protocols, randomized pilot studies, and case reports tracks these interventions to identify promising signals that warrant larger-scale replication.
Recent clinical work has highlighted distinct pharmacotherapeutic agents, including the acetylcholinesterase inhibitor pyridostigmine for neuromuscular weakness and orthostatic intolerance, the metabolic enhancer oxaloacetate for cognitive dysfunction, and the antidiabetic drug metformin for preventing Long COVID and protecting synapses. In parallel, early-phase investigations are evaluating the IL-15 superagonist ANKTIVA for viral clearance, the potassium channel blocker amifampridine for neuromuscular fatigue, the NMDA receptor antagonist ketamine for rapid fatigue reduction, and mitochondrial-supportive combinations like 5-ALA/SFC.
Although these pilot trials and mechanistic perspectives provide clear biological rationales, the current evidence base is early and preliminary. Many trials are small, single-center, or open-label, which limits statistical power and increases the risk of bias. Consequently, none of these interventions have achieved regulatory approval or established definitive efficacy in large-scale, placebo-controlled settings, leaving substantial uncertainty regarding their long-term safety, optimal dosing, and generalizability.
Why This Matters
Finding safe and effective treatments for ME/CFS and Long COVID requires translating complex, multi-systemic pathomechanisms into targeted clinical interventions. Identified abnormalities—such as impaired vascular regulation (preload failure), neurovascular coupling deficits, mitochondrial respiration blockages, and hyperactive microglial signaling—directly align with the pharmacology of several existing medications. Repurposing these therapeutics provides an accelerated pathway to clinical applications compared to developing novel compounds from scratch.
Systematic research into these agents offers objective measures of efficacy to complement subjective patient-reported fatigue. For example, demonstrating that pyridostigmine improves peak oxygen consumption ( peak) and hand grip strength connects vascular autonomic regulation directly with muscular capacity. Similarly, evaluating oxaloacetate’s impact on objective cognitive tests (e.g., DANA Brain Vital) and metformin’s ability to prevent neurodegenerative protein aggregation in pre-clinical models grounds these interventions in measurable cellular pathways. These trials build a scientific foundation for stratifying patients into biologically defined subgroups who are most likely to benefit from specific metabolic, vascular, or immunomodulatory mechanisms.
State of Evidence
- Established:
- Metformin decreases the risk of developing post-COVID-19 condition (Long COVID) when administered during acute infection in overweight or obese adults.
- Pyridostigmine improves peak oxygen consumption ( peak) and right atrial pressure in patients with exertional intolerance and confirmed preload failure during invasive cardiopulmonary exercise testing.
- Oxaloacetate is safe and well-tolerated at daily doses up to 2,000 mg in clinical cohorts.
- Plausible but early:
- Pyridostigmine enhances hand grip strength and decreases heart rate elevations upon standing.
- Oxaloacetate improves objective cognitive processing speed and reduces total symptom burden in Long COVID and ME/CFS.
- Metformin prevents cognitive deficits and synaptic damage in animal models by blocking the S1-spike-protein-induced hypoxia switch (HIF-1α) and downstream protein aggregation.
- Amifampridine increases functional scores and reduces excessive sleep requirements in patients with Post-COVID Syndrome.
- Low-dose ketamine infusions induce rapid, transient reductions in fatigue scores, peaking at 24 hours.
- Continuous sipping of high-dose cromolyn sodium improves symptoms of comorbid Mast Cell Activation Syndrome (MCAS) in post-viral patients.
- Sonlicromanol improves fatigue, pain, and physical function over long-term (52-week) open-label administration in mitochondrial disease models.
- Oral 5-ALA/SFC combined with ubiquinone resolves severe chronic fatigue in individuals with specific genetic mutations affecting mitochondrial function (e.g., ADCK1).
- Not established:
- Definitive clinical efficacy or regulatory approval for any of these repurposed therapies in treating ME/CFS or Long COVID.
- The efficacy of metformin, ketamine, or amifampridine in large-scale, parallel-group, randomized, placebo-controlled trials specifically for ME/CFS.
- Long-term safety and tolerability of continuous high-dose protocols (e.g., cromolyn sodium or oxaloacetate) beyond several months.
- Key limitations:
- Small sample sizes in pilot studies (e.g., 20 patients for pyridostigmine hand grip, 10 patients for ketamine crossover, 5 patients for amifampridine and cromolyn series) limit statistical power and generalizability.
- High risk of placebo effects and response bias in open-label studies and retrospective case series.
- Crossover trial designs for drugs like ketamine are prone to carryover effects that confound efficacy comparisons against comparators like midazolam.
- Preclinical data (e.g., metformin’s protection of rat synapses, sonlicromanol’s primary mitochondrial disease trial) require human translational validation in ME/CFS before clinical conclusions can be drawn.
Timeline
2022-05-15 - Pyridostigmine trial identifies preload failure mechanism and acute exercise improvement
A randomized, placebo-controlled clinical trial of 39 female patients with ME/CFS showed that a single 60 mg dose of the acetylcholinesterase inhibitor pyridostigmine acutely increased peak oxygen consumption ( peak) and improved cardiac filling pressures during a second invasive cardiopulmonary exercise test (iCPET). This study provides physiological evidence that impaired vascular regulation (preload failure) is a key driver of exertional intolerance in ME/CFS, indicating that acetylcholinesterase inhibition can partially correct this deficit. Furthermore, the worsening of filling pressures in the placebo group during back-to-back testing offers an objective, physiological demonstration of post-exertional malaise. However, the study evaluated only the acute, immediate effects of a single dose, leaving it unproven whether daily oral use of pyridostigmine provides long-term functional improvement or safe symptom control. The findings also do not clarify if the drug’s benefits are restricted to patients with confirmed small fiber neuropathy.
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2023-06-08 - Metformin in COVID-OUT trial demonstrates prevention of Long COVID
The phase 3, randomized, quadruple-blind COVID-OUT trial involving 1,126 overweight or obese adults demonstrated that early outpatient treatment with metformin (initiated within seven days of acute SARS-CoV-2 symptom onset) reduced the incidence of a subsequent Long COVID diagnosis by 41% over a 10-month follow-up period. This trial establishes that a safe, inexpensive, and widely available metabolic medication can prevent the development of post-viral sequelae when taken during the acute phase. The preventive effect was most pronounced when metformin was started within three days of symptom onset, whereas ivermectin and fluvoxamine showed no efficacy. However, the trial was limited to adults aged 30–85 with overweight or obesity, meaning it does not prove whether metformin prevents Long COVID in individuals with normal body mass index or in younger cohorts. Additionally, the study was designed for prevention during acute infection and does not address whether metformin is effective as a treatment for individuals who have already developed chronic Long COVID.
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2023-06-22 - Vericiguat Phase 2 trial initiated for endothelial dysfunction in Post-COVID Syndrome
A randomized, double-blind, placebo-controlled Phase 2 clinical trial (NCT05697640) was initiated by Charité University in Berlin to investigate whether the soluble guanylate cyclase stimulator vericiguat improves physical function in patients with Post-COVID-19 Syndrome. The trial targets patients with confirmed endothelial dysfunction—a condition where impaired function of the inner lining of small blood vessels reduces local blood flow and tissue oxygenation. By evaluating a drug known to enhance nitric oxide signaling and promote vasodilation, the study aims to test if correcting endothelial impairment translates into improved physical capacity and reduced fatigue. However, the trial is ongoing with results yet to be published, and it remains to be proven whether vericiguat is safe and effective in this population. It also does not establish whether the drug’s mechanisms are applicable to post-viral patients who do not exhibit measurable signs of microvascular endothelial dysfunction.
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2024-01-25 - Amifampridine case series indicates reduction in neuromuscular fatigue and hypersomnia
A case series of five patients with Post-COVID Syndrome, including double-blind discontinuation trials in two participants, showed that the potassium channel blocker amifampridine led to a normalization of daily sleep duration and a significant increase in functional Bell scores (mean rising from 28 to 82). This observation suggests that amifampridine, which increases acetylcholine release at the neuromuscular junction, may target a shared neuromuscular pathway driving profound fatigue and excessive sleep requirements in post-viral syndromes. The recurrence of severe fatigue when active drug was replaced with a placebo during the discontinuation phase strengthens the likelihood of a direct pharmacological effect. However, the study’s extremely small sample size and descriptive nature limit the generalizability of the findings. It does not prove amifampridine’s efficacy or safety in a large, representative clinical trial, nor does it establish optimal dosing guidelines for the broader Long COVID or ME/CFS populations.
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2024-11-06 - Sonlicromanol Phase 2b program shows long-term improvement in mitochondrial symptoms
A Phase 2b trial program evaluating the mitochondrial-targeted drug sonlicromanol in adults with genetically confirmed m.3243A>G mitochondrial disease demonstrated significant long-term improvements in fatigue, pain, physical quality of life, and balance during a 52-week open-label extension. Although the initial 28-day randomized, placebo-controlled portion of the study failed to meet its primary cognitive endpoint, post-hoc analyses and the subsequent year-long extension showed clinical benefits, particularly in patients who were more severely affected at baseline. This trial provides supportive evidence that modulating cellular oxidative stress and inflammatory distress pathways can alleviate systemic symptoms associated with mitochondrial dysfunction, which is hypothesized to play a major role in ME/CFS. However, because the primary endpoint of the randomized portion was not met, the short-term efficacy of sonlicromanol remains unproven. Furthermore, the 52-week extension lacked a control group, and the drug has not yet been directly tested in patients diagnosed with ME/CFS or Long COVID.
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2024-12-26 - Genetic case study links ADCK1 mutation to ME/CFS and resolution via oral 5-ALA/SFC
A genetic case report of a 35-year-old woman with severe, long-standing ME/CFS identified a novel frameshift mutation in the ADCK1 gene, a gene critical for mitochondrial coenzyme Q10 synthesis, and documented significant clinical improvements following oral supplementation with 5-aminolevulinic acid with sodium ferrous citrate (5-ALA/SFC) and ubiquinone. This case provides a molecular link between a specific genetic mutation, mitochondrial energy failure, and severe chronic fatigue, illustrating the potential for gene-targeted metabolic therapies. The patient’s dose-dependent improvement in fatigue and daily activity levels suggests that addressing coenzyme Q10 and heme synthesis pathways can restore cellular energy production. However, this study describes only a single patient, which does not prove that the ADCK1 mutation is a common cause of ME/CFS or that 5-ALA/SFC is broadly effective for patients without this specific genetic variation. It also remains unverified whether the heterozygous ADCK1 mutation is sufficient on its own to cause ME/CFS pathobiology.
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2025-07-18 - REGAIN trial of Oxaloacetate in Long COVID reports cognitive gains but misses primary fatigue endpoint
The randomized, double-blind, placebo-controlled REGAIN trial of 69 adults with Long COVID showed that a daily dose of 2,000 mg of oral oxaloacetate (OAA) for 42 days did not produce a statistically significant difference in fatigue reduction compared to placebo on the primary Chalder Fatigue Questionnaire (CFQ). However, secondary measures revealed that the oxaloacetate group experienced significantly greater improvements in objective cognitive function (using the DANA Brain Vital battery) and a more rapid reduction in total symptom burden at day 21. These results suggest that targeting mitochondrial bioenergetics with oxaloacetate may selectively alleviate cognitive dysfunction (“brain fog”) and overall symptom severity, even when generalized fatigue scores remain unchanged. Nevertheless, because the trial failed to meet its primary efficacy endpoint for fatigue, the clinical utility of oxaloacetate as a general anti-fatigue agent remains unproven. The study’s single-center design, modest sample size, and short 42-day duration also limit the strength of the evidence.
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2025-08-07 - Review proposes multi-systemic metformin protocols for ME/CFS metabolic dysfunction
A comprehensive literature review proposed a strong biological rationale for repurposing metformin to address the metabolic, inflammatory, and gut dysbiosis pathways characteristic of ME/CFS and Long COVID. The authors consolidated evidence showing that metformin inhibits mitochondrial complexes I and IV, reduces reactive oxygen species, modulates mTOR signaling to improve energy regulation, and exerts anti-inflammatory and mast-cell-stabilizing effects. This perspective highlights metformin as a multi-action agent that could serve as a core component of a multi-faceted treatment strategy targeting metabolic stress. However, the review is a synthesis of previous in vitro, animal, and clinical data, which does not prove that metformin is clinically effective or safe for patients already suffering from chronic ME/CFS. Additionally, the drug’s significant gastrointestinal side effects represent a major clinical challenge that may limit its usability in patients with pre-existing gut dysbiosis or irritable bowel syndrome.
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2025-08-19 - ANKTIVA Phase 2 trial initiated to target viral reservoirs in Long COVID
A Phase 2, exploratory, single-arm clinical trial (NCT07123727) was initiated to evaluate the safety and immunological effects of the IL-15 superagonist ANKTIVA (nogapendekin alfa inbakicept-pmln) in up to 40 adults with Long COVID. The trial targets persistent viral reservoirs and immune dysregulation by using immunotherapy to boost the count and activity of Natural Killer (NK) cells and CD8+ T cells, which are often depleted or dysfunctional in chronic post-viral states. If successful, this immune-enhancing approach could help clear lingering viral proteins and restore healthy immune surveillance. However, the trial is currently recruiting, and no clinical efficacy or safety data have been published yet. The single-arm, open-label design of the trial also means that future results will lack a placebo control group, making it difficult to separate the drug’s therapeutic effects from spontaneous recovery.
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2025-09-03 - Pyridostigmine trial demonstrates short-term improvement in hand grip strength and orthostatic tolerance
A within-subject clinical study of 20 patients with post-infectious ME/CFS showed that a single 30 mg dose of pyridostigmine significantly improved hand grip strength recovery (by a median of 2.6 kg) and reduced heart rate elevations during a standing test (from a median of 17 bpm to 13 bpm) after one hour. These findings suggest that pyridostigmine can provide rapid, temporary relief for muscle fatiguability and orthostatic intolerance by increasing acetylcholine availability at the neuromuscular junction and enhancing parasympathetic activity. The objective improvement in muscle strength recovery directly addresses the neuromuscular weakness reported by patients. However, the study’s non-randomized, non-controlled design and very small cohort size introduce a high risk of bias. It does not prove the efficacy of pyridostigmine in a controlled setting, nor does it determine whether these acute benefits persist with chronic dosing.
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2025-09-16 - Solriamfetol trial reports reduction in fatigue severity and improved executive function in ME/CFS
An 8-week, double-blind, randomized, placebo-controlled Phase 4 trial involving 38 adults with ME/CFS showed that the dual norepinephrine-dopamine reuptake inhibitor solriamfetol significantly reduced self-reported fatigue severity and improved overall executive function, particularly metacognitive skills like planning and memory. This trial indicates that targeting central monoamine pathways can alleviate cognitive and fatigue symptoms, offering a wakefulness-promoting therapeutic option. However, the trial was small and conducted at a single site, which limits the generalizability of the findings. The study did not find a significant improvement in the interference of fatigue on daily life activities, and the rapid dose titration caused side effects such as anxiety and sleep loss in several participants, leaving optimal dosing and long-term tolerability unproven.
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2025-09-23 - Oxaloacetate ME/CFS trial demonstrates cognitive improvement and fatigue-cognition coupling
A 90-day, randomized, double-blind, placebo-controlled trial of 82 adults with ME/CFS demonstrated that a daily dose of 2,000 mg of oral oxaloacetate significantly improved objective cognitive performance (using DANA Brain Vital) at the 60-day mark compared to a placebo control. The study identified a strong “fatigue–cognition coupling” effect only in the oxaloacetate-treated group, where higher baseline fatigue was strongly associated with reduced cognitive gains, suggesting the drug acts on a biological pathway that links these two core symptoms. Upright activity time (UP Time) also showed a modest increase at the 30-day mark. However, the study did not find statistically significant differences in overall responder rates or general fatigue scores between the treatment and placebo groups. It remains unproven whether oxaloacetate can reliably reduce generalized fatigue or if it is only effective in a specific sub-phenotype of patients with coupled cognitive and metabolic dysfunction.
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2025-11-07 - Metformin shown to protect brain synapses and prevent protein clumping in SARS-CoV-2 spike model
A preclinical molecular study using human neuronal cell lines and a rat model demonstrated that intranasal exposure to the SARS-CoV-2 S1 spike protein caused cognitive impairment, synaptic dysfunction, and aggregation of toxic phosphorylated tau and alpha-synuclein, all of which were prevented by treatment with metformin. The study maps a direct pathway where the viral spike protein stabilizes the hypoxia switch HIF-1α, turning off genes essential for healthy brain connections, which is blocked by metformin’s metabolic action. This provides a clear molecular mechanism explaining metformin’s protective role against “brain fog” and neurodegenerative markers during post-viral syndromes. However, these findings are based on human cell lines and a six-week rodent model, which does not prove that metformin will reverse established cognitive impairment or stop neurodegenerative-like protein clumping in chronic human patients. It also does not clarify if vaccination-induced spike protein exposure behaves similarly to the viral models used in the study.
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2026-01-22 - High-dose continuous oral cromolyn sodium improves comorbid MCAS symptoms
A retrospective case series of five patients with ME/CFS or Long COVID and comorbid Mast Cell Activation Syndrome (MCAS) showed that a continuous sipping regimen of high-dose oral cromolyn sodium (1,600 to 2,400 mg daily) significantly improved fatigue, cognitive function, and heart rate control. By spreading the total dose throughout the day in a water bottle rather than using discrete bolus doses, the protocol aims to maintain stable plasma concentrations of the drug and improve patient tolerance. This provides a practical dosing strategy for patients who fail standard low-dose regimens. However, the retrospective case series design lacks a control group, and the very small number of patients (five) means the efficacy and safety of this high-dose protocol are not proven. Systematic prospective trials are required to validate these findings and to monitor for potential adverse effects of long-term high-dose cromolyn exposure.
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2026-01-22 - Ketamine crossover trial reports rapid but transient reductions in chronic fatigue
A randomized, double-blind, crossover trial involving ten participants with chronic fatigue (including ME/CFS and fibromyalgia) showed that a single low-dose ketamine infusion reduced fatigue scores by 21% at three days and by nearly 39% at 24 hours. The study demonstrates that low-dose ketamine, an NMDA receptor antagonist, can induce rapid, clinically relevant reductions in severe chronic fatigue. However, due to the small sample size and a strong placebo response in the active control (midazolam) group, the difference in fatigue reduction between the groups did not reach statistical significance. The crossover design also introduced significant carryover effects, where the fatigue-reducing effects of the first infusion influenced the baseline of the second period. These limitations mean that the efficacy of ketamine over active controls remains unproven, and parallel-design trials are needed to confirm the drug’s therapeutic value.
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2026-03-04 - Molecular hydrogen review consolidates early evidence for oxidative stress reduction
A narrative mini-review of clinical and mechanistic evidence concluded that consuming hydrogen-rich water is a promising, low-risk adjunctive therapy that may improve fatigue and physical function in patients with ME/CFS and Long COVID. The review highlights molecular hydrogen’s selective antioxidant properties, which allow it to reduce cellular oxidative stress and support mitochondrial health without disrupting essential cellular signaling. Results from three early-stage, developmental clinical trials suggest the treatment is feasible and well-tolerated. However, the current clinical evidence is restricted to small, open-label or pilot studies relying heavily on self-reported outcomes. These early findings do not prove the clinical efficacy of molecular hydrogen, and larger, placebo-controlled trials incorporating objective biometrics and biomarkers are needed to confirm the therapeutic benefits.
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2026-06-03 - Trial protocol published to evaluate acupuncture for cognitive function in post-COVID ME/CFS
A randomized controlled trial protocol published in Frontiers in Neurology by Luo et al. outlines the design of a prospective, three-armed trial (NCT07357688) evaluating the efficacy and neural mechanisms of acupuncture in 129 patients with post-COVID ME/CFS and 30 healthy controls. Participants are randomized to verum acupuncture, sham acupuncture (non-penetrating), or waitlist control for 8 weeks (3 sessions/week). The primary outcome is change in information processing speed (Symbol Digit Modalities Test [SDMT]), with secondary outcomes including cognitive batteries and brain metabolites/connectivity measured via fMRI. As a trial protocol, this publication outlines study methodology only and does not report clinical efficacy or safety data.
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2026-06-08 - Preclinical study of sodium deoxyribonucleate in post-viral chronic fatigue syndrome model
In an animal study published in the Medical academic journal, Filatenkova et al. evaluated the nucleotide-based drug sodium deoxyribonucleate in a Poly I:C Wistar rat model of post-viral chronic fatigue syndrome. A single administration of the drug on day 1 post-induction improved exploratory activity, reduced anxiety-like behaviors, normalized splenic lymphocyte activities, and normalized post-exercise plasma lactate levels, although muscle weakness was not resolved. Hypothalamic cytokine gene expression was also restored. As a preclinical study in a rodent model, these findings demonstrate early biological pathways and do not represent evidence of clinical efficacy or safety in humans. Furthermore, the drug was administered immediately after induction, representing acute protection/prevention rather than treatment of long-standing chronic illness.
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2026-06-25 - MYOFLAME-19 trial of losartan and prednisone for post-COVID cardiac inflammation presents results at International ME/CFS Conference 2026
Prof. Dr. Valentina Puntmann presented findings from the MYOFLAME-19 trial, a 16-week randomized, placebo-controlled trial evaluating the angiotensin receptor blocker losartan (with or without the corticosteroid prednisone) in 279 patients with post-COVID fatigue syndrome showing subclinical cardiac inflammation on MRI. While the study did not meet its primary confirmatory endpoint of improving left ventricular ejection fraction (LVEF) using a conservative unpaired t-test, an ANCOVA analysis adjusting for baseline LVEF showed a statistically significant treatment effect. The trial showed directional proof of concept with improvements in cardiac volume, reduced tissue and systemic inflammation (CRP, D-dimer, lymphocytes), and reduced fatigue. However, the study suffered from a high attrition rate (11.8%), and LVEF may not be the optimal endpoint for post-infectious endothelial dysfunction.
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2026-06-28 - Preclinical metabolomics study indicates Ginseng stem-leaf saponins modulate brain-gut pathways in chronic fatigue syndrome mice
A preclinical animal study published in the Journal of Pharmaceutical and Biomedical Analysis by Wu et al. evaluated the effects of Ginseng stem-leaf saponins (GSLS) in a chronic fatigue mouse model induced by a long-term forced-swimming protocol. Using untargeted metabolomics, the authors analyzed brain tissue and fecal samples, identifying 17 differential metabolites in the brain and 17 in feces. GSLS supplementation partially normalized metabolic abnormalities mapping to lipid-derived mediators, membrane-lipid remodeling, and energy/redox cofactor pathways. As a preclinical study in a mouse model, these findings represent early exploratory biology and do not demonstrate therapeutic efficacy or clinical safety in human patients.
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2026-06-28 - Preclinical study finds Sijunzi decoction modulates gut microbiota and metabolic profiles in chronic fatigue syndrome rats
A study published in the Journal of Chromatography B by Shan et al. evaluated the traditional herbal formulation Sijunzi Decoction (SJZD) in a multi-factor stress-induced rat model of chronic fatigue syndrome. Daily administration of SJZD for 30 days improved body weight, gastrointestinal motility, exhaustive swimming time, and skeletal muscle ATPase content, while regulating 25 serum and 7 fecal metabolites and enhancing intestinal microbiota diversity. As a preclinical study in a rodent model, these findings demonstrate biological pathways in animals and do not represent clinical efficacy or safety in humans, and the specific bioactive components of the multi-herb formulation were not isolated.
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2026-06-28 - Randomized controlled trial preprint evaluates specialized pro-resolving mediators and telerehabilitation in Post-COVID Condition
The ARACOV-02 double-blind randomized controlled trial (n=144), published as a preprint, evaluated the combination of a specialized pro-resolving mediator (SPM)-enriched marine oil supplement and a 12-week telerehabilitation program in individuals with Post-COVID-19 Condition. Although no statistically significant between-group differences were observed after 12 weeks, both the treatment and placebo groups showed significant within-group improvements in quality of life, fatigue, and functional capacity (partly due to the active rehabilitation program in both arms). The SPM group demonstrated significant improvements in dyspnea that were absent in the placebo group, and high supplement compliance was associated with broader clinical improvements. As a preprint, this work has not yet undergone formal peer review to validate the findings.
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Open Questions
- What are the optimal patient stratification criteria? Given the heterogeneity of ME/CFS and Long COVID, identifying specific clinical phenotypes (such as preload failure, mitochondrial dysfunction, or MCAS) is crucial to match patients with the most appropriate pharmacotherapeutic mechanism.
- Do acute signals translate to long-term clinical efficacy? Pilot trials demonstrating short-term or single-dose improvements (e.g., pyridostigmine for exercise capacity or ketamine for fatigue) must be followed by long-term tolerability and safety studies.
- Can combination therapies target multiple pathways simultaneously? Because these conditions are multi-systemic, research is needed to determine if combining low-risk metabolic, autonomic, and immunomodulatory interventions yields synergistic clinical benefits.