Evaluating the Neuromodulatory Effect of Ketamine in Long COVID-19

Phase 2

• Conditions: Long COVID
• Interventions: Drug: Ketamine only

• Registration Number: NCT06821087
• Lead Sponsor: University of Texas at Austin

Brief Summary

Plain Language Summary:

This study is a clinical trial to see if ketamine can help treat symptoms of Long COVID, especially fatigue and problems with thinking clearly (often called "brain fog"). Long COVID is a condition that affects people even after they have recovered from COVID-19, causing ongoing health issues like tiredness, memory problems, and difficulty concentrating. Right now, there are very few treatments available for these symptoms, and many people are looking for new options to feel better.

What is the study trying to find out? Does ketamine help reduce fatigue and improve thinking skills in people with Long COVID? Does ketamine improve overall quality of life and mental health for people with Long COVID? Is ketamine safe and well-tolerated for people with Long COVID? How does ketamine affect the body's biological processes, like inflammation and brain function? How will the study work?

The study will include 20 adults between 18 and 65 years old who have Long COVID symptoms like fatigue or brain fog.

Participants will first meet with researchers to answer health questions, take surveys about their symptoms, and do tests to check their thinking skills. Some participants will also have a brain scan (MRI) and give a blood sample to look at markers of inflammation.

Participants will then receive four ketamine treatments over two weeks at a specialized clinic. The ketamine will be given as an injection, with the dose slightly increasing during the treatment period.

After six weeks, participants will return for follow-up tests to see if their symptoms have improved. This includes repeating the surveys, thinking tests, and for some, another MRI and blood test.

Why ketamine? Ketamine is a medicine originally used for anesthesia but has also been found to help with depression and other mental health issues. Researchers think it might help with Long COVID symptoms because it can reduce inflammation in the brain and improve how the brain functions. People with Long COVID often have signs of inflammation and changes in brain chemicals, which ketamine might help balance.

What are the potential benefits? Participants might experience less fatigue and clearer thinking after ketamine treatment. They could also feel better overall in terms of mood and quality of life. Since ketamine can work quickly, some people may notice improvements shortly after starting the treatment.

What are the risks? Ketamine can cause side effects like feeling dizzy, anxious, or having an unusual sense of reality (sometimes called dissociation). It may also cause temporary increases in blood pressure or heart rate. All treatments will be carefully monitored by healthcare professionals to ensure safety.

Who can participate? Adults aged 18-65 with Long COVID who have significant fatigue or thinking problems can join. People will not be able to participate if they have certain health conditions like severe heart disease, uncontrolled high blood pressure, or a history of severe mental health disorders.

Why is this study important? Long COVID affects millions of people, and many are struggling to find treatments that work. This study is one of the first to explore ketamine as a potential treatment for Long COVID symptoms. If ketamine helps, it could lead to more research and eventually new treatment options for people living with Long COVID.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2025-02-10
• Study First Submitted QC: 2025-02-10
• Study First Posted: 2025-02-11
• Status Verified: 2025-04
• Study Start: 2025-04-28
• Last Update Submitted: 2025-04-29
• Last Update Posted: 2025-05-02
• Primary Completion: 2026-01
• Study Completion: 2026-03

Recruitment & Eligibility

• Status: ENROLLING_BY_INVITATION
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Adults aged 18-65 years diagnosed with LC and possess a documented history of positive COVID-19 diagnostic testing or a probable infection as determined by a healthcare provider.
• One persistent symptom of fatigue or neurocognitive dysfunction as defined by rating their symptoms as moderate to severe on the screening form.
• English as a primary language OR comprehension of English suitable to understand research staff instructions.

The first 5 male and first 5 female participants to enroll will be invited to participate in the MRI portion of the study, provided they have no contraindications to MRI on screening. If participants decline to participate in the MRI portion, it will be offered to subsequent participants upon enrollment, ensuring there is no gender imbalance greater than 6 to 4 for the MRI portion.

Exclusion Criteria

Contraindications to ketamine therapy:

• Current substance use disorder
• Current mania or psychosis
• Recent myocardial infarction or stroke (within 1 year)
• Unstable cardiovascular disease (including uncontrolled high blood pressure > 180/110 mmHg)
• Uncontrolled seizure disorder
• Pregnancy

Additional exclusion criteria include:

• Recent COVID-19 infection or reinfection within 8 weeks

• Prior receipt of ketamine treatment

• History of treatment resistant depression (TRD) prior to development of LC

  • Defined as completing a trial (2 months of treatment at highest tolerated dose) of 3 or more psychotropic medications from at least 2 classes of medications (i.e. SSRIs, SNRIs, antipsychotic medications, or mood stabilizers such as lithium, lamotrigine, Depakote, or oxcarbazepine)
  • Psychotropic medications used during treatment of LC will not be counted as medications used for TRD

• Current severe depression or anxiety, and/or active suicidal ideation

  • Severe depression and anxiety defined as scoring > 19 on PHQ-9 screening or > 14 on GAD-7 screening.
  • Active suicidal ideation is defined as answering "yes" to question #9 on the PHQ-9

• History of bipolar disorder, schizophrenia, or schizoaffective disorder

• History of suicide attempt or psychiatric hospitalization for any reason in the last 5 years

• Current benzodiazepine or naltrexone medication use within 4 weeks of enrollment as these may decrease or block the therapeutic effect of ketamine treatment

Note participants with contraindications to MRI imaging will be excluded from the subset of 10 patients undergoing that testing

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Ketamine Therapy	Ketamine only	Participants in this arm will receive four intramuscular (IM) ketamine injections over a two-week period. The initial dose will be 0.5 mg/kg during the first session, increasing to 0.65 mg/kg in the second session, and 0.75 mg/kg for the third and fourth sessions. Injections will be administered at least three days apart. All treatments will be conducted under medical supervision at a specialized clinic with standard safety protocols in place. Vital signs will be monitored before, during, and after each session to assess tolerability. Participants will also undergo assessments of fatigue, cognitive function, quality of life, and biomarkers pre- and post-treatment. A subset of 10 participants will receive fMRI imaging pre- and post-treatment.

Primary Outcome Measures

Name	Time	Method
PROMIS SF v1.0 - Fatigue 8a	At enrollment and at the post-treatment assessment visit, 6 weeks following completion of the ketamine treatment.	A patient-reported questionnaire measuring the severity and impact of fatigue on daily activities over the past 7 days. Higher scores indicate greater fatigue.
PROMIS SF v2.0 Cognitive Function 4a	At enrollment and at the post-treatment assessment visit, 6 weeks following completion of the ketamine treatment.	A patient-reported tool that measures perceived cognitive abilities, such as memory, concentration, and mental clarity, over the past 7 days. Higher scores reflect better cognitive function.
BrainCheck Cognitive Battery	At enrollment and at the post-treatment assessment visit, 6 weeks following completion of the ketamine treatment.	A computerized series of neuropsychological tests assessing objective cognitive functions, including memory, attention, executive function, processing speed, and response inhibition. Scores are age-normalized.
Number of participants with treatment-related adverse events as assessed by standardized interview	Adverse events will be assessed at each of the four ketamine treatment sessions and during the final post-treatment assessment, which occurs six weeks after the last ketamine injection.	A standardized interview conducted post-treatment to identify and record any physical or psychological side effects experienced by participants during the ketamine therapy.

Secondary Outcome Measures

Name	Time	Method
PROMIS Global 10 v1.2	Collected at baseline (pre-treatment) and at the post-treatment assessment (6 weeks after the final ketamine session).	A 10-item questionnaire assessing overall physical, mental, and social health, including pain, fatigue, and emotional well-being.
NASA Task Load Index (NASA-TLX)	Collected at baseline (pre-treatment) and at the post-treatment assessment (6 weeks after the final ketamine session).	A tool used to evaluate perceived mental workload, assessing factors like mental demand, effort, and frustration during cognitive tasks like BrainCheck.
Patient Health Questionnaire-9 (PHQ-9)	Collected before each ketamine treatment session, at baseline, and at the post-treatment assessment (6 weeks post-treatment).	A widely used self-report measure to assess the severity of depressive symptoms over the past two weeks.
Generalized Anxiety Disorder-7 (GAD-7)	Collected before each ketamine treatment session, at baseline, and at the post-treatment assessment (6 weeks post-treatment).	A widely used 7-item scale measuring the severity of anxiety symptoms over the past two weeks.
Depression in Medically Ill 10 Scale (DMI-10)	Collected at baseline (pre-treatment) and at the post-treatment assessment (6 weeks after the final ketamine session).	A measure designed to assess depressive symptoms specifically in individuals with medical conditions, focusing on somatic and cognitive symptoms.
Long COVID Review of Systems	Collected at baseline (pre-treatment) and at the post-treatment assessment (6 weeks after the final ketamine session).	A comprehensive symptom checklist adapted from the WHO's Global COVID-19 Clinical Platform, evaluating the range and severity of Long COVID symptoms.
Neuroimaging (MRI) Outcomes	Performed at baseline and repeated at the post-treatment assessment (6 weeks after the final ketamine session) for participants in the imaging subgroup.	Functional MRI (fMRI) scans will evaluate changes in brain structure and connectivity in a subset of 10 participants, providing insight into the neurological effects of ketamine.
Serum Biomarker Analysis	Collected at baseline and at the post-treatment assessment (6 weeks after the final ketamine session).	Blood samples will be analyzed for inflammatory and metabolic markers, including cytokines and metabolites in the kynurenine pathway, to assess biological responses to ketamine treatment.

Trial Locations

Locations (1)

UT Health Austin; 🇺🇸 Austin, Texas, United States