Idiopathic Normal Pressure Hydrocephalus (INPH)Phase 2DRAINNCT04975269
Acetazolamide Trial in Normal Pressure Hydrocephalus
A Phase 2 study testing Acetazolamide in people with Idiopathic Normal Pressure Hydrocephalus (INPH), run by Uppsala University Hospital at 1 site in Sweden.
Trial summary
A pharmacological treatment to patients with normal pressure hydrocephalus (NPH) is missing. The aim is to investigate if acetazolamide given to patients with NPH improves gait function and study the pathophysiological mechanisms leading to reduced symptoms. Read more about this study
- Who is it for?
- Ages 50 to 82 years
- Conditions the study is for
- Idiopathic Normal Pressure Hydrocephalus (INPH)
- What is being tested?
- Acetazolamide
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 50 participants
- Where
- 1 siteSweden
- Study dates
- 17 Feb 2022to 21 Apr 2026
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 to 82 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Diagnosis of idiopathic normal pressure hydrocephalus according to international guidelines
- Age ≥ 50 years and ≤ 82 years
- Cognitive function with Mini-Mental State Examination > 20 points or cognitive domain of iNPH scale ≥ 30 points.
- MRI image characteristic of normal pressure hydrocephalus, defined as callosal angle < 90 degrees and dilated lateral ventricles or pattern of disproportionately enlarged subarachnoid space hydrocephalus (DESH).
- Signed informed consent form
Who cannot join
- Exclusion criteria for MRI examination
- Participation in another medical trial
- Other disease likely to impact the symptoms of the patient
- Wheelchair user or unable to walk without support
- Reduced kidney function with GFR < 50
- Reduced liver function (increased INR or alanine transaminase concentrations in plasma elevated more than 1.5 times reference values)
Show all 16Show fewer
- Known heart failure
- Low concentrations of electrolytes in blood plasma that, according to the investigator, prevents participation in the study
- Angle-closure glaucoma
- Allergy to acetazolamide, sulfonamides, or sulfonamide derivatives
- Treatment with phenytoin, valproate, carbamazepine, lithium, oral anticoagulants, thiazide-diuretics, or acetylsalicylic acid > 100 mg/day
- Inability to swallow capsules of the same size as the investigational medicinal products (will be tested using empty capsules when the patient is asked to participate in the study)
- Average walking time for the three walking tests < 10.5 seconds for men and < 11.5 seconds for women.
- Average walking time for the three walking tests > 50 seconds
- Inability to comply with the study treatment independently, and a concurrent lack of individuals to help the patient comply with the treatment during the study period
- Fertile woman without highly effective contraception. A Fertile woman will be tested with pregnancy test before inclusion is possible.
Trial locations and contacts
1 site in 1 country.
Sweden1 site
Department of Clinical Neurophysiology, Neurosurgery and Neurology, Uppsala University Hospital
Uppsala
About this study
Official title: Double-blind Randomized Acetazolamide Trial in Normal Pressure Hydrocephalus
A pharmacological treatment to patients with normal pressure hydrocephalus (NPH) is missing. The aim is to investigate if acetazolamide given to patients with NPH improves gait function and study the pathophysiological mechanisms leading to reduced symptoms.
Patients will be randomized to acetazolamide or placebo and duration of treatment will be from diagnosis to the day of shunt surgery. Target dose is 500 mg/day. Study design is a double-blind randomized controlled trial and the plan is to include 42-50 patients. The study is investigator-initiated without financial sponsorship from the industry.
Read the detailed description
Background: The only available treatment for normal pressure hydrocephalus (NPH) is implantation of a neurosurgical shunt system that reduces symptoms in two out of three cases. Postoperative complications are common, causing reoperations in 20-30% within the first years after surgery. A pharmacological treatment is missing.
In three previous studies, acetazolamide, a reversible inhibitor of the carbonic anhydrase enzyme, was used as treatment off-label. In the first of these studies, 15 patients with NPH were treated with doses 250-500 mg/day and 10 patients improved (Aimard G et. al.). The second study was a case report of one patient with NPH who improved after receiving the dose 500 mg/day (Garcia-Gasco P et. al.). The most recent study used doses of 125-375 mg/day and included 8 patients of whom 5 improved. Furthermore, the last study reported a reduction of the periventricular edema that is often present in the white matter close to the lateral ventricles in patients with NPH (Alperin N et. al.). These three studies were open label with no blinding or control group.
Study design: Study design is a double-blind randomized placebo-controlled trial. The study is investigator-initiated without financial sponsorship from the industry. The plan is to consecutively include 42-50 patients with NPH. Patients will be randomized to acetazolamide or placebo and take the study drug from diagnosis (baseline) to admission for shunt surgery. Waiting time for shunt surgery at the center of the study is approximately 4-8 months at the moment. The dose will be titrated to 250 mg x 2 during 4-6 weeks. Two phone visits with a study nurse and routine blood samples are controlled during the titration phase to rule out side effects.
Evaluations of clinical symptoms and blood samples for blood biomarkers are collected at baseline, after 3 months and when the study drug is stopped. Lumbar cerebrospinal fluid (CSF) is collected at baseline and intraventricular CSF is collected during shunt surgery. All patients are investigated after shunt surgery, 3 months postoperatively with evaluation of symptoms and blood samples. Blood- and CSF samples are stored in a biobank.
In a subgroup of 24-26 patients, an MRI of the brain is performed before the start of study drug and after 3 months. In this subgroup also assessments of symptoms and blood samples for analysis of plasma biomarkers will be collected in connection with the MRI scans.
- Being tested
- Acetazolamide, Placebo
- Keywords
- normal pressure hydrocephalus, iNPH, Acetazolamide, Diamox, RCT
- Medical subject headings
- Hydrocephalus, Normal Pressure
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
AcetazolamideDrug
Also called Diamox
Target dose: 500 mg / day
PlaceboDrug
Placebo
| Study group | Role | What they receive |
|---|---|---|
| Acetazolamide | Active comparator | Acetazolamide (active) Receives: Drug: Acetazolamide |
| Placebo | Placebo comparator | Placebo Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportional change in gait function
Gait function is determined by one variable that is calculated as the mean time and number of steps of three different gait tests: 10 meter walking in self chosen speed, timed up and go test (TUG) and 3 m walking backwards.
The two fastest attempts of three attempts for each test are documented. The mean time and number of steps of the two fastest attempts for the three tests are calculated to a single variable and the proportional difference between study visits is used as the primary outcome variable.
Measured: Change from baseline gait function immediately after intervention (at time of shunt surgery)
Secondary outcomes (12)
Change in idiopathic normal pressure hydrocephalus (iNPH) scale
Swedish idiopathic normal pressure hydrocephalus (iNPH) scale that is a combination of subscales for gait, balance, cognition and continence. Minimum value is 0 and maximum value is 100. High values indicate better function.
Measured: Change from baseline iNPH-scale score immediately after intervention (at time of shunt surgery)
Change in volume of periventricular hyperintensities
Measured using volumetric MRI
Measured: Change from baseline at 3 months
Change in cerebral blood perfusion
Measured using pseudo continuous arterial spin labeling (MRI perfusion)
Measured: Change from baseline at 3 months
Change in quantified CSF flow in cerebral aqueduct
Measured using phase contrast MRI
Measured: Change from baseline at 3 months
Change in parenchymal water content
Measured using Synthetic MRI
Measured: Change from baseline at 3 months
Change in cerebral myelin volume
Measured using Synthetic MRI
Measured: Change from baseline at 3 months
Changes in plasma biomarkers
Change in plasma levels of neurofilament light chain protein, Total-tau, amyloid beta-42, glial fibrillary acidic protein will be measured using Quanterix (SIMOA).
Measured: Change from baseline immediately after intervention (at time of shunt surgery)
Change in CSF biomarkers
CSF levels of neurofilament light chain protein, Total-tau, amyloid beta-42, glial fibrillary acidic protein will be measured using Quanterix (SIMOA).
Measured: Change from baseline immediately after intervention (at time of shunt surgery)
Changes in plasma and CSF proteins
Semi-quantified levels of approximately 200 proteins are measured with proximity extension assay (Neurology panel and Neuro exploratory panel, Olink.com).
Measured: Change from baseline immediately after intervention (at time of shunt surgery)
Patients self reported assessment of symptoms
Gait, cognition, continence, balance, activities of daily life and quality of life is rated by patients on a questionnaire using 4-level scales.
Measured: Change from baseline immediately after intervention (at time of shunt surgery)
Change in Euro-Quality of Life-5 dimension-5L (EQ-5D-5L) descriptive system
Measured using EQ-5D-5L using the descriptive system.
Measured: Change from baseline EQ-5D-5L score immediately after intervention (at time of shunt surgery)
Change in Euro-Quality of Life-5 dimension-5L (EQ-5D-5L) VAS
Measured using the visual analogue scale (VAS) in EQ-5D-5L.
Measured: Change from baseline EQ-5D-5L score immediately after intervention (at time of shunt surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jul 2021
- Study start17 Feb 2022
- Primary completion18 Nov 2024
- Study completion21 Apr 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for Idiopathic Normal Pressure Hydrocephalus (INPH)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Double-blind randomized trial.
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 50 participants (actual)
Sponsor and investigators
- Lead sponsor
- Uppsala University Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Uppsala University, Swedish Society for Medical Research
- Responsible party
- Principal investigator, Johan Virhammar, Uppsala University Hospital
- Investigators
- Johan Virhammar, MD, PhD, Principal investigator, Department of Neuroscience, Uppsala University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04975269
- Sponsor's protocol ID
- NPH-01
- Acronym
- DRAIN
- Status last verified
- Apr 2026
- First submitted
- 15 Jun 2021
- Last updated
- 6 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Individual participant data that underlie the results reported in any publications from this study, can be shared after deidentification.
Publications
Aimard G, Vighetto A, Gabet JY, Bret P, Henry E. [Acetazolamide: an alternative to shunting in normal pressure hydrocephalus? Preliminary results]. Rev Neurol (Paris). 1990;146(6-7):437-9. French.
PubMed 2399408Adams RD, Fisher CM, Hakim S, Ojemann RG, Sweet WH. SYMPTOMATIC OCCULT HYDROCEPHALUS WITH "NORMAL" CEREBROSPINAL-FLUID PRESSURE. A TREATABLE SYNDROME. N Engl J Med. 1965 Jul 15;273:117-26. doi: 10.1056/NEJM196507152730301. No abstract available.
PubMed 14303656Garcia-Gasco P, Salame Gamarra F, Tenllado Doblas P, Chazarra Talens C. [Complete resolution of chronic hydrocephalus of adult with acetazolamide]. Med Clin (Barc). 2005 Apr 9;124(13):516-7. doi: 10.1157/13073568. No abstract available. Spanish.
PubMed 15847775Alperin N, Oliu CJ, Bagci AM, Lee SH, Kovanlikaya I, Adams D, Katzen H, Ivkovic M, Heier L, Relkin N. Low-dose acetazolamide reverses periventricular white matter hyperintensities in iNPH. Neurology. 2014 Apr 15;82(15):1347-51. doi: 10.1212/WNL.0000000000000313. Epub 2014 Mar 14.
PubMed 24634454Relkin N, Marmarou A, Klinge P, Bergsneider M, Black PM. Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery. 2005 Sep;57(3 Suppl):S4-16; discussion ii-v. doi: 10.1227/01.neu.0000168185.29659.c5.
PubMed 16160425Hellstrom P, Klinge P, Tans J, Wikkelso C. A new scale for assessment of severity and outcome in iNPH. Acta Neurol Scand. 2012 Oct;126(4):229-37. doi: 10.1111/j.1600-0404.2012.01677.x. Epub 2012 May 16.
PubMed 22587624Virhammar J, Fasth O, Ekblom M, Ekman O, Holmstrand N, Fallmar D, Nyholm D. Safety, tolerability, and efficacy of acetazolamide in idiopathic normal pressure hydrocephalus (DRAIN) in Sweden: a randomised, double-blind, placebo-controlled, phase 2 trial. Lancet Neurol. 2026 Jun;25(6):550-559. doi: 10.1016/S1474-4422(26)00126-2.
PubMed 42127932
Study at a glance
From the registry record, last updated by the sponsor on 6 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Double-blind Randomized Acetazolamide Trial in Normal Pressure Hydrocephalus
- ClinicalTrials.gov ID
- NCT04975269
- Acronym / sponsor ID
- DRAIN / NPH-01
- Keywords
- normal pressure hydrocephalus, iNPH, Acetazolamide, Diamox, RCT
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 50 participants (actual)
- Lead sponsor
- Uppsala University HospitalUniversity, hospital or other
- Collaborators
- Uppsala University, Swedish Society for Medical Research
- Study start
- 17 Feb 2022 (actual)
- Primary completion
- 18 Nov 2024 (actual)
- Study completion
- 21 Apr 2026 (actual)
- First posted
- 23 Jul 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A pharmacological treatment to patients with normal pressure hydrocephalus (NPH) is missing. The aim is to investigate if acetazolamide given to patients with NPH improves gait function and study the pathophysiological mechanisms leading to reduced symptoms.
Patients will be randomized to acetazolamide or placebo and duration of treatment will be from diagnosis to the day of shunt surgery. Target dose is 500 mg/day. Study design is a double-blind randomized controlled trial and the plan is to include 42-50 patients. The study is investigator-initiated without financial sponsorship from the industry.
Detailed description
Background: The only available treatment for normal pressure hydrocephalus (NPH) is implantation of a neurosurgical shunt system that reduces symptoms in two out of three cases. Postoperative complications are common, causing reoperations in 20-30% within the first years after surgery. A pharmacological treatment is missing.
In three previous studies, acetazolamide, a reversible inhibitor of the carbonic anhydrase enzyme, was used as treatment off-label. In the first of these studies, 15 patients with NPH were treated with doses 250-500 mg/day and 10 patients improved (Aimard G et. al.). The second study was a case report of one patient with NPH who improved after receiving the dose 500 mg/day (Garcia-Gasco P et. al.). The most recent study used doses of 125-375 mg/day and included 8 patients of whom 5 improved. Furthermore, the last study reported a reduction of the periventricular edema that is often present in the white matter close to the lateral ventricles in patients with NPH (Alperin N et. al.). These three studies were open label with no blinding or control group.
Study design: Study design is a double-blind randomized placebo-controlled trial. The study is investigator-initiated without financial sponsorship from the industry. The plan is to consecutively include 42-50 patients with NPH. Patients will be randomized to acetazolamide or placebo and take the study drug from diagnosis (baseline) to admission for shunt surgery. Waiting time for shunt surgery at the center of the study is approximately 4-8 months at the moment. The dose will be titrated to 250 mg x 2 during 4-6 weeks. Two phone visits with a study nurse and routine blood samples are controlled during the titration phase to rule out side effects.
Evaluations of clinical symptoms and blood samples for blood biomarkers are collected at baseline, after 3 months and when the study drug is stopped. Lumbar cerebrospinal fluid (CSF) is collected at baseline and intraventricular CSF is collected during shunt surgery. All patients are investigated after shunt surgery, 3 months postoperatively with evaluation of symptoms and blood samples. Blood- and CSF samples are stored in a biobank.
In a subgroup of 24-26 patients, an MRI of the brain is performed before the start of study drug and after 3 months. In this subgroup also assessments of symptoms and blood samples for analysis of plasma biomarkers will be collected in connection with the MRI scans.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Double-blind randomized trial.
| Arm | Type | Receives |
|---|---|---|
| Acetazolamide | Active comparator | Drug: AcetazolamideAcetazolamide (active) |
| Placebo | Placebo comparator | Drug: PlaceboPlacebo |
Who may qualify
- Ages
- 50 to 82 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Diagnosis of idiopathic normal pressure hydrocephalus according to international guidelines
- Age ≥ 50 years and ≤ 82 years
- Cognitive function with Mini-Mental State Examination > 20 points or cognitive domain of iNPH scale ≥ 30 points.
- MRI image characteristic of normal pressure hydrocephalus, defined as callosal angle < 90 degrees and dilated lateral ventricles or pattern of disproportionately enlarged subarachnoid space hydrocephalus (DESH).
- Signed informed consent form
Key exclusion criteria (16 listed)
- Exclusion criteria for MRI examination
- Participation in another medical trial
- Other disease likely to impact the symptoms of the patient
- Wheelchair user or unable to walk without support
- Reduced kidney function with GFR < 50
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| AcetazolamideAlso: DiamoxTarget dose: 500 mg / day | Drug | Acetazolamide |
| PlaceboPlacebo | Drug | Placebo |
Primary outcome
Proportional change in gait function
Time frame: Change from baseline gait function immediately after intervention (at time of shunt surgery)
Gait function is determined by one variable that is calculated as the mean time and number of steps of three different gait tests: 10 meter walking in self chosen speed, timed up and go test (TUG) and 3 m walking backwards. The two fastest attempts of three attempts for each test are documented. The mean time and number of steps of the two fastest attempts for the three tests are calculated to a single variable and the proportional difference between study visits is used as the primary outcome variable.
12 secondary outcomes
Change in idiopathic normal pressure hydrocephalus (iNPH) scale
Time frame: Change from baseline iNPH-scale score immediately after intervention (at time of shunt surgery)
Change in volume of periventricular hyperintensities
Time frame: Change from baseline at 3 months
Change in cerebral blood perfusion
Time frame: Change from baseline at 3 months
Change in quantified CSF flow in cerebral aqueduct
Time frame: Change from baseline at 3 months
Change in parenchymal water content
Time frame: Change from baseline at 3 months
Change in cerebral myelin volume
Time frame: Change from baseline at 3 months
Changes in plasma biomarkers
Time frame: Change from baseline immediately after intervention (at time of shunt surgery)
Change in CSF biomarkers
Time frame: Change from baseline immediately after intervention (at time of shunt surgery)
Changes in plasma and CSF proteins
Time frame: Change from baseline immediately after intervention (at time of shunt surgery)
Patients self reported assessment of symptoms
Time frame: Change from baseline immediately after intervention (at time of shunt surgery)
Change in Euro-Quality of Life-5 dimension-5L (EQ-5D-5L) descriptive system
Time frame: Change from baseline EQ-5D-5L score immediately after intervention (at time of shunt surgery)
Change in Euro-Quality of Life-5 dimension-5L (EQ-5D-5L) VAS
Time frame: Change from baseline EQ-5D-5L score immediately after intervention (at time of shunt surgery)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 May 2026.
- Background: PubMed 2399408Aimard G, Vighetto A, Gabet JY, Bret P, Henry E. [Acetazolamide: an alternative to shunting in normal pressure hydrocephalus? Preliminary results]. Rev Neurol (Paris). 1990;146(6-7):437-9. French.
- Background: PubMed 14303656Adams RD, Fisher CM, Hakim S, Ojemann RG, Sweet WH. SYMPTOMATIC OCCULT HYDROCEPHALUS WITH "NORMAL" CEREBROSPINAL-FLUID PRESSURE. A TREATABLE SYNDROME. N Engl J Med. 1965 Jul 15;273:117-26. doi: 10.1056/NEJM196507152730301. No abstract available.
- Background: PubMed 15847775Garcia-Gasco P, Salame Gamarra F, Tenllado Doblas P, Chazarra Talens C. [Complete resolution of chronic hydrocephalus of adult with acetazolamide]. Med Clin (Barc). 2005 Apr 9;124(13):516-7. doi: 10.1157/13073568. No abstract available. Spanish.
- Background: PubMed 24634454Alperin N, Oliu CJ, Bagci AM, Lee SH, Kovanlikaya I, Adams D, Katzen H, Ivkovic M, Heier L, Relkin N. Low-dose acetazolamide reverses periventricular white matter hyperintensities in iNPH. Neurology. 2014 Apr 15;82(15):1347-51. doi: 10.1212/WNL.0000000000000313. Epub 2014 Mar 14.
- Background: PubMed 16160425Relkin N, Marmarou A, Klinge P, Bergsneider M, Black PM. Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery. 2005 Sep;57(3 Suppl):S4-16; discussion ii-v. doi: 10.1227/01.neu.0000168185.29659.c5.
- Background: PubMed 22587624Hellstrom P, Klinge P, Tans J, Wikkelso C. A new scale for assessment of severity and outcome in iNPH. Acta Neurol Scand. 2012 Oct;126(4):229-37. doi: 10.1111/j.1600-0404.2012.01677.x. Epub 2012 May 16.
- Derived from this study: PubMed 42127932Virhammar J, Fasth O, Ekblom M, Ekman O, Holmstrand N, Fallmar D, Nyholm D. Safety, tolerability, and efficacy of acetazolamide in idiopathic normal pressure hydrocephalus (DRAIN) in Sweden: a randomised, double-blind, placebo-controlled, phase 2 trial. Lancet Neurol. 2026 Jun;25(6):550-559. doi: 10.1016/S1474-4422(26)00126-2.
- Individual participant dataSharing planned: Yes. Individual participant data that underlie the results reported in any publications from this study, can be shared after deidentification.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Johan Virhammar, MD, PhD principal investigator
Department of Neuroscience, Uppsala University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Acetazolamide in people with Idiopathic Normal Pressure Hydrocephalus (INPH), run by Uppsala University Hospital at 1 site in Sweden.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Sweden. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Proportional change in gait function (time frame: Change from baseline gait function immediately after intervention (at time of shunt surgery)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04975269, which also lists 7 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 May 2026.