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NCT Number: NCT06178952

Transcranial Pulse Stimulation (TPS) in Post-COVID-19

The objective of the present study is to demonstrate treatment efficacy of transcranial pulse stimulation for patients with Post-COVID-19 related neurological symptoms (fatigue, cognitive deficits, mood deterioration). Fatigue, as measured by the Fatigue Impact Scale (FIS), will represent the primary outcome variable. The verum treatment will be compared to a sham (placebo) condition.

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Key information

Age range

20 year–80 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Medical University of Vienna

Vienna, State of Vienna, 1090, Austria

Location status: Recruiting

Location contact

Michael Mitterwallner, Dr.

CONTACT

[email protected]

+43 650 9626003

Roland Beisteiner, Prof.

CONTACT

[email protected]

+43/(0)1 40400-34080

About this study

This clinical trial aims to investigate the treatment efficacy of transcranial pulse stimulation (TPS) using the NEUROLITH device (Storz Medical AG, Tägerwilen, Switzerland) in individuals with neurological post-COVID-19-symptoms. TPS is a novel brain stimulation therapy based on non-invasive ultrasound pulses and first published in 2019 by the Medical University of Vienna, Austria (Beisteiner et al. Advanced Science, 2019). The study employs a double-blind, randomized, placebo-controlled design with parallel groups (verum vs. sham). The anticipated timeframe for the entire study is 2 years, during which each participant is expected to be actively engaged for a period of 3-4 months. The aim is to include 102 patients. The randomization ratio is 1:1, ensuring an even distribution between the verum (active treatment) and sham (placebo) groups. Three assessment points are scheduled (Baseline, PostStim, 1monthPostStim). Furthermore, to determine potential effects over time, limited data collection (involving only FIS, BDI-II, SF-36 and BI-PEM) is planned at later time points, specifically at 3 months post-stimulation, 6 months post-stimulation, 12 months post-stimulation, and 24 months post-stimulation.

Hypotheses

  • H0: There is no significant difference in the effectiveness of transcranial pulse stimulation (TPS) and placebo treatment in improving primary and secondary endpoints.
  • H1: There is a significant difference in the effectiveness of transcranial pulse stimulation (TPS) and placebo treatment in improving primary and secondary endpoints.

Timeline

Each study participant will undergo the following sequence:

  • Initial information session and clarification of relevant medical findings regarding inclusion and exclusion criteria
  • Baseline screening:
  • 3-4 assessment sessions per patient within 14 days, including informed consent
  • Patients who do not meet the predefined cut-off values for BDI, FIS, and MoCA will be excluded from subsequent study phases
  • Transcranial pulse stimulation
  • 5 stimulations per patient within 10 days
  • One stimulation per day lasting approximately 30 minutes.
  • Post-stimulation assessment (PostStim)
  • Conducted during the week following brain stimulation
  • 2-3 assessment sessions per patient within 7 days
  • One-month post-stimulation assessment (1monthPostStim)
  • Conducted one month after brain stimulation
  • 2-3 assessment sessions per patient within 7 days

Deviations of + 5 days from the intended timeline are considered tolerable.

Sample Size Calculation

The sample size calculation conducted with G*Power incorporated a small effect size (f = .10), α error probability of .05, and a power of 0.8, resulting in an estimate of 102 patients.

Important note: Originally, the study was designed as a multicenter study with the still-existing Austrian center (N=90) and an Italian center (N=30). Since study realization at the Italian center was ultimately not possible, the trial was streamlined to a single-center design. Consequently, enrollment at the Austrian center was refined so that at least 102 participants would reach the primary endpoint, thus meeting the original sample-size requirement. This administrative change was made prior to any analyses and does not affect the prespecified endpoints or procedures.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Signed written informed consent
  • PCR-confirmed SARS-CoV-2 infection, laboratory confirmed antibody detection for SARS-CoV-2, or physician-verified COVID-19 infection
  • At least 12 months after initial SARS-CoV-2 infection that led to Post-COVID (subsequent SARS-CoV-2 infections are not a reason for exclusion)
  • Diagnosis of Post-COVID Syndrome or independent suspected diagnosis of Post-COVID Syndrome (Considering that physicians generally hesitate to provide clear-cut Post-COVID diagnoses, a tentative diagnosis by an independent general practitioner or a specialist in a field associated with Post-COVID will suffice for entering this study)
  • Age: 20-80
  • Evidence of a negative pregnancy test if medically adequate

Exclusion criteria

  • Clinically relevant realization of pre-COVID diseases with similar symptoms as Post-COVID
  • MoCA score <17 (cut-off for dementia)
  • BDI-II score ≥29 (cut-off for severe depression)
  • FIS <10 (cut-off for no fatigue)
  • Brain implants
  • Non-MR-compatible metal parts in the body
  • Metal parts in the head
  • Use of anticoagulants
  • Non-MR-compatible claustrophobia
  • Non-MR-compatible pacemaker
  • Pregnant and breastfeeding women
  • Clinically relevant history of surgery on the head, heart, or vessels
  • Relevant corticosteroid treatments administered within 6 weeks prior to the first application
  • Tumor of the head if relevant for treatment
  • Blood clotting disorders
  • Participation in other studies

Treatment and study plan

Transcranial pulse stimulation Verum

Device

Participants are slated to undergo a total of five TPS sessions over a 10-day interval. Each stimulation session will endure approximately 30 minutes and will be administered once daily.

Transcranial pulse stimulation Sham

Device

Placebo treatment will be performed using the same medical device, handpiece and treatment paradigm as in the verum treatment with one difference: the standoff device at the end of the handpiece. This device is designed to replicate the appearance, feel, and sound of the verum system, while omitting the transmission of any pulses.

Primary outcomes

  1. Fatigue Impact Scale (FIS)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Fatigue Impact Scale (Fisk et al., 1994) is an instrument to measure the impact of fatigue symptoms. This self-report measure consists of 40 items divided into three subscales: cognitive functioning (10 items), physical functioning (10 items) and psychosocial functioning (20 items). In the validated German version, the statements are scored from 0-4 (0=never, 4=very often) leading to a total score of 0-160.

Secondary outcomes

  1. Beck Depression Inventory (BDI-II)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Beck Depression Inventory (BDI-II) is one of the most widely used instruments for measuring the severity of depression. It is a 21-item questionnaire for self-evaluation with 0-3 scores per item, ranging from 0 (normal state) to 63 (severe depression).

  2. Montreal Cognitive Assessment (MOCA)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    Montreal Cognitive Assessment (Nasreddine et al., 2005) is a clinical standard test for evaluating the following cognitive functions: visuospatial/executive, naming, memory, attention, language, abstraction, recall and orientation. The maximum score is 30 points.

  3. 36-Item Short Form Health Survey (SF-36)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The 36-item short-form health survey (Ware et al., 1992) is a widely used instrument to measure quality of life. The 36-item patient-reported survey covers eight health concepts including physical functioning (10 items), role limitations due to physical health (4 items), role limitations due to emotional problems (3 items), energy/fatigue (4 items), emotional well-being (5 items), social functioning (2 items), pain (2 items), and general health (5 items). All questions are scored on a scale from 0 (worst health) to 100 (best health).

  4. Trail Making Test A and B (TMT-A and TMT-B)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Trail Making Test (Reitan et al., 1958) consist of two parts A and B. For each part, patients need to fulfill a task by connecting letters and/or numbers in the right way. The scoring of both parts is done by taking the time required to complete them.

  5. Positive and Negative Affect Schedule (PANAS)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Positive and Negative Affect Schedule (Watson et al., 1988) is an instrument to assess mood, specifically distinguishing between positive and negative affect. It has two subscales (positive and negative) and consists out of 20 items which are scored using a 5-point scale (1= not at all - 5 = extremely).

  6. Beck Anxiety Inventory (BAI)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Beck Anxiety Inventory (Beck et al., 1988) is a self-reported scale to measure anxiety. It consists of 21 items, which are scored from 0-3. The BAI has a total range from 0 to 63.

  7. Six Minute Walking Test (6MWT)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The six-minute walking test, developed by the American Thoracic Society 2002, is an exercise test to assess aerobic capacity and endurance. The patients are asked to walk as far as they can within 6 minutes. Subjective tests (Borg-Scale, 0-10) will be administers before and after walking.

  8. Test of Attentional Performance (TAP)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Test of Attentional Performance (Zimmermann et al., 2002) is an instrument to measure attentional function. There are 14 subscales, including Sustained Attention, Vigilance, and Divided Attention. It will be carried out digitally using the TAP software package.

  9. Verbal Learning and Memory Test (VLMT)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The German version of the Verbal Learning Memory Test by Helmstaedter and colleagues (2001) is an instrument to measure different parameters of declarative verbal memory such as learning or recognition performance. It consists of a learning phase, in which patients need to learn two lists of 15 words each, a delayed recall and a recognition test.

  10. Stroop color word test (STROOP)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The Stroop Color-Word Test (Stroop, 1935) is a useful and reliable psychological assessment tool (Lezak, Howieson, & Loring, 2004) that measures a person's ability to inhibit an automatic response in favor of an atypical one. Specifically, it involves identifying the ink color of incongruously labeled color words (van Boxtel et al., 2001). The test can measure cognitive performance functions such as naming speed, selectivity, and alertness (Bäumler & Stroop, 1985).

  11. Satisfaction With Life Scale (SWLS)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The SWLS (Satisfaction with Life Scale), developed by Diener and colleagues (1985), is a widely used self-report questionnaire designed to measure individuals' subjective satisfaction with their own lives. It consists of five items that capture different aspects of life satisfaction.

  12. Somatization subscale of the Symptom Check List-90-R (SCL-90-R SOM)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The SCL-90-R (Schmitz et al., 2000) is a 90-item self-report symptom inventory used in clinical and research settings to evaluate psychological symptoms and distress. Only the SOM (Somatization) subscale within the SCL-90-R will be used for the present study. It consists of 12 items on a 5-point Likert scale that assess physical symptoms. The maximum score for the subscale is 48 points.

  13. Post-Exertional Malaise (BI-PEM)

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    The German version of the DSQ PEM questionnaire (Cotler et al., 2018; Jason & Sunnquist, 2018) comprises three subscales and a total of 11 items, focusing on post-exertional malaise. The subscales include questions concerning frequency, severity and duration of the symptoms after engaging in activities over the past 6 months.

  14. Neuroimaging

    Time frame: Baseline - 1 week after stimulation - 1 month after stimulation

    Magnetic resonance imaging (MRI) will be recorded the week before, the week after and 1 month after TPS stimulations by center 1 (Vienna) for the Austrian study population. MR measurements will be performed using a 3 T SIEMENS PRISMA MR with a 64-channel head coil. MRI images will be obtained to assess changes in structural and functional brain connectivity.

Study contacts

Contact information is provided by the study sponsor or research team.

Michael Mitterwallner, Dr.

CONTACT

[email protected]

+43 650 9626003

Roland Beisteiner, Prof.

CONTACT

[email protected]

+43/(0)1 40400-34080

Sponsors and collaborators

Lead sponsor

Medical University of Vienna

Other

Registry information

Important dates

Study start
2024
Primary completion
2027
Study completion
2027
First posted
Dec 21, 2023
Registry last updated
Dec 23, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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