Postural Tachycardia SyndromePhase 2/3NCT00685919
Peripheral Dopamine in Postural Tachycardia Syndrome
A Phase 2/3 study testing Carbidopa in people with Postural Tachycardia Syndrome and Orthostatic Intolerance, run by Vanderbilt University at 1 site in United States.
Trial summary
The purpose of the proposed research is to determine how changes in kidney dopamine (DA) activity influence urinary sodium excretion. We will decrease DA activity in the kidney by inhibiting DA synthesis via carbidopa administration. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Postural Tachycardia Syndrome, Orthostatic Intolerance
- What is being tested?
- Carbidopa
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 32 participants
- Where
- 1 siteUnited States
- Study dates
- May 2008to Dec 2021
- Phase
- Phase 2/3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Patients diagnosed with POTS by the Vanderbilt Autonomic Dysfunction Center based on the following stringent criteria: 1) history of daily orthostatic symptoms for at least 6 months; 2) increase in heart rate (HR) of at least 30 bpm with standing or a standing HR of at least 120 bpm; 3) absence of orthostatic hypotension (defined as a fall in blood pressure (BP)>20/10 mm Hg); and 4) absence of conditions, such as dehydration, substantial weight loss, or systemic illnesses, that could provoke orthostatic intolerance
- Upright plasma NE at least 600 pg/mL in patients
- Non-smoking
- Free of medications with the potential to influence BP
- Able and willing to provide informed consent -
Who cannot join
- Overt cause for postural tachycardia (such as acute dehydration)
- Significant cardiovascular, pulmonary, hepatic, or hematological disease by history or screening results
- Positive urine b-hcg pregnancy test
- Evidence of cardiac structural disease (by clinical examination or prior echocardiogram)
- Hypertension defined as a BP>145/95 (off medications) or need for antihypertensive medications
- Evidence of significant conduction system delay (QRS duration >120 ms) on electrocardiogram
- Inability to give, or withdraw, informed consent
Trial locations and contacts
1 site in 1 country.
United States1 site
Vanderbilt University Medical Center
Nashville, Tennessee, 37232
About this study
Official title: Kidney Dopamine Effects on Urinary Sodium Excretion in Postural Tachycardia Syndrome
The purpose of the proposed research is to determine how changes in kidney dopamine (DA) activity influence urinary sodium excretion. We will decrease DA activity in the kidney by inhibiting DA synthesis via carbidopa administration. We want to compare findings in normal volunteers and in patients with postural tachycardia syndrome (POTS). We will test the null hypothesis (Ho) that the effects of oral carbidopa administration on urinary sodium excretion will not differ between patients with POTS and healthy volunteers.
Read the detailed description
We will determine whether inhibition of renal dopamine formation by carbidopa administration leads to a decrease in urinary excretion of dopamine and sodium and whether the response differs in POTS and control populations. Carbidopa effects will be compared to those of a matching placebo, and the sequence of treatments (carbidopa before placebo or placebo before carbidopa) will be randomized.
Each subject will undergo a complete history and physical examination, including an electrocardiogram (EKG).
- After achieving sodium balance on a 200 mEq/day sodium diet, subjects will collect urine over 24hr for baseline assessment of sodium and catecholamines.
- On this day, the subjects will be admitted to the CRC.
- An 18 gauge intravenous catheter will be inserted in order to draw blood.
- The subjects will fast from 7 pm until after the next morning's testing.
- In the morning, while still supine after the overnight sleep, heart rate and blood pressure will be recorded, and blood will be drawn. The subjects will then stand for 10 minutes. Heart rate and blood pressure will be measured at intervals, and an upright blood sample will be collected.
- The subjects will be asked to collect their urine to end the 24hr urine collection. Another 24hr urine collection will be started.
- Treatment A (Carbidopa 200mg or placebo) will be given orally following the void, at approximately 7 am. Additional doses will be taken every 6 hours with the last dose at 7 am the following morning.
- Subjects will be free to follow their normal routine during the day until returning to the CRC for the night. However, they will need to consume the 200 mEq/day study diet for each meal, collect all urine, and take study medication on schedule
- After returning to the CRC, the subjects will fast after 7 pm.
- In the morning, supine and standing heart rate and blood pressure will be recorded, and the subjects will be asked to collect their urine to end the 24hr urine collection.
- The final dose of study medication (Carbidopa 200mg or placebo) will be given orally following the void, at approximately 7 am.
- Supine heart rate and blood pressure will be measured and supine blood samples will be collected hourly for 4 hours after the treatment and at 8 hours after the treatment. Subjects must rest supine for at least 30 minutes before each blood draw.
- At 2 hours after treatment, subjects will stand for 10 minutes for upright blood pressure and heart rate measurements and collection of an upright blood sample, as described above. Participants will be asked to rate the severity of common orthostatic symptoms while supine and upright.
- Urine will be collected for two 4-hour periods after treatment and from 8 hours to 24 hours after treatment.
- Fixed-sodium study diet will be provided after the 4-hour measurements and in the evening.
After at least a 1 day washout period, the study will be repeated with Treatment B
- Being tested
- Carbidopa, Placebo
- Keywords
- Dopamine, Natriuresis, Catecholamines
- Medical subject headings
- Postural Orthostatic Tachycardia Syndrome, Orthostatic Intolerance
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CarbidopaDrug
200 mg every 6 hours for 5 doses given orally
PlaceboDrug
every 6 hours for 5 doses, given orally, and matching Carbidopa
| Study group | Role | What they receive |
|---|---|---|
| Carbidopa then Placebo | Experimental | Carbidopa 200 mg every 6 hours orally for 5 doses followed by Placebo every 6 hours for 5 doses Receives: Drug: Carbidopa; Drug: Placebo |
| Placebo then Carbidopa | Experimental | Placebo matching carbidopa given every 6 hours orally for 5 doses followed by Carbidopa Receives: Drug: Carbidopa; Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
24 Hour Urinary Sodium Excretion During Treatment Normalized to Creatinine
Urine was collected for 24hr during treatment. Urinary volume was measured and the urine was analyzed for sodium and creatinine concentrations. Total amounts of sodium and creatinine excreted over the 24 hr were calculated and results expressed as ratio of sodium:creatinine.
Measured: Immediately before the 1st dose of placebo or carbidopa to immediately before the 5th dose (approximately 24 hours)
Secondary outcomes (7)
Systolic Blood Pressure Measured at 8 Hours After the Last Dose of Placebo or Carbidopa
Systolic blood pressure was measured once using a Dinamap non-invasive oscillometric blood pressure monitor, 2-4 hours after lunch and after at least 30 minutes of resting supine.
Measured: 8 hours after the last dose of placebo or carbidopa
Plasma Catecholamines (Norepinephrine) After the Last Dose of Placebo or Carbidopa
Blood samples were collected while resting supine for at least 30 minutes and 2 to 4 hours after lunch. For catecholamine measurements, blood was collected in chilled vacuum tubes with EDTA. Plasma was separated and stored with added reduced glutathione (Amersham International PLC) at -70°C until the assay. Plasma catecholamines were measured by a method that involves batch alumina extraction followed by high-performance liquid chromatography (HPLC) for separation with electrochemical detection and quantification.
Measured: 8 hours after the last dose of placebo or carbidopa
Plasma Catecholamines (DOPA) After the Last Dose of Placebo or Carbidopa
Blood samples were collected while resting supine for at least 30 minutes and 2 to 4 hours after lunch. For catecholamine measurements, blood was collected in chilled vacuum tubes with EDTA. Plasma was separated and stored with added reduced glutathione (Amersham International PLC) at -70°C until the assay. Plasma catecholamines were measured by a method that involves batch alumina extraction followed by high-performance liquid chromatography (HPLC) for separation with electrochemical detection and quantification.
Measured: 8 hours after the last dose of placebo or carbidopa
24 Hour Urinary Catecholamine (DOPA) Excretion During Treatment Normalized to Creatinine
Urine was collected over 24 hours during treatment. The urinary volume was measured and the urine was analyzed for creatinine and catecholamines. Total amounts of creatinine and catecholamines were calculated and the results are expressed as catecholamine:creatinine.
Measured: Immediately before the 1st dose of Placebo or Carbidopa and ending immediately before the last dose (approximately 24 hours)
24 Hour Urinary Catecholamine (Dopamine) Excretion During Treatment Normalized to Creatinine
Urine was collected over 24 hours during treatment. The urinary volume was measured and the urine was analyzed for creatinine and catecholamines. Total amounts of creatinine and catecholamines were calculated and the results are expressed as catecholamine:creatinine.
Measured: Immediately before the 1st dose of Placebo or Carbidopa and ending immediately before the last dose (approximately 24 hours)
Supine Plasma Renin Activity 2 Hours After the Last Dose of Placebo or Carbidopa
Blood samples were collected while resting supine for at least 30 minutes and 1 1/2 to 2 hours after breakfast. Samples were processed and sent to the Vanderbilt Clinic Laboratory for assay.
Measured: 2 hours after the last dose of placebo or carbidopa
Plasma Sodium After the Last Dose of Placebo or Carbidopa
Blood samples were collected while resting supine for at least 30 minutes and 2 to 4 hours after lunch. Samples were processed and sent to the Vanderbilt Clinical Laboratory for assay.
Measured: 8 hours after the last dose of placebo or carbidopa
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 May 2008 (estimated)
- Study startMay 2008
- Primary completionJul 2020
- Study completionDec 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for Postural Tachycardia SyndromeStudies 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 2/3
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Vanderbilt University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Alfredo Gamboa, Vanderbilt University
- Investigators
- Alfredo J Gamboa, MD, Principal investigator, Vanderbilt University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00685919
- Sponsor's protocol ID
- 101499
- Other IDs
- HL071784-05A1
- Status last verified
- Jan 2022
- First submitted
- 27 May 2008
- Last updated
- 24 Jan 2022
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
Publications
Carey RM. Theodore Cooper Lecture: Renal dopamine system: paracrine regulator of sodium homeostasis and blood pressure. Hypertension. 2001 Sep;38(3):297-302. doi: 10.1161/hy0901.096422.
PubMed 11566894Goldstein DS, Stull R, Eisenhofer G, Gill JR Jr. Urinary excretion of dihydroxyphenylalanine and dopamine during alterations of dietary salt intake in humans. Clin Sci (Lond). 1989 May;76(5):517-22. doi: 10.1042/cs0760517.
PubMed 2498027Jose PA, Eisner GM, Felder RA. Renal dopamine and sodium homeostasis. Curr Hypertens Rep. 2000 Apr;2(2):174-83. doi: 10.1007/s11906-000-0079-y.
PubMed 10981146Kuchel O, Buu NT, Unger T. Dopamine-sodium relationship: is dopamine a part of the endogenous natriuretic system? Contrib Nephrol. 1978;13:27-36. doi: 10.1159/000402132.
PubMed 710137Stokes GS, Monaghan JC, Pillai DN. Effects of carbidopa and of intravenous saline infusion into normal and hypertensive subjects on urinary free and conjugated dopamine. J Hypertens. 1997 Jul;15(7):761-8. doi: 10.1097/00004872-199715070-00008.
PubMed 9222944Jacob G, Robertson D, Mosqueda-Garcia R, Ertl AC, Robertson RM, Biaggioni I; New Collective Author. Hypovolemia in syncope and orthostatic intolerance role of the renin-angiotensin system. Am J Med. 1997 Aug;103(2):128-33. doi: 10.1016/s0002-9343(97)00133-2.
PubMed 9274896
Study at a glance
From the registry record, last updated by the sponsor on 24 Jan 2022. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Kidney Dopamine Effects on Urinary Sodium Excretion in Postural Tachycardia Syndrome
- ClinicalTrials.gov ID
- NCT00685919
- Acronym / sponsor ID
- 101499
- Keywords
- Dopamine, Natriuresis, Catecholamines
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Vanderbilt UniversityUniversity, hospital or other
- Study start
- May 2008 (actual)
- Primary completion
- Jul 2020 (actual)
- Study completion
- Dec 2021 (actual)
- First posted
- 29 May 2008 (estimated)
- Results
- Posted 20 Sep 2021
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of the proposed research is to determine how changes in kidney dopamine (DA) activity influence urinary sodium excretion. We will decrease DA activity in the kidney by inhibiting DA synthesis via carbidopa administration. We want to compare findings in normal volunteers and in patients with postural tachycardia syndrome (POTS). We will test the null hypothesis (Ho) that the effects of oral carbidopa administration on urinary sodium excretion will not differ between patients with POTS and healthy volunteers.
Detailed description
We will determine whether inhibition of renal dopamine formation by carbidopa administration leads to a decrease in urinary excretion of dopamine and sodium and whether the response differs in POTS and control populations. Carbidopa effects will be compared to those of a matching placebo, and the sequence of treatments (carbidopa before placebo or placebo before carbidopa) will be randomized.
Each subject will undergo a complete history and physical examination, including an electrocardiogram (EKG).
- After achieving sodium balance on a 200 mEq/day sodium diet, subjects will collect urine over 24hr for baseline assessment of sodium and catecholamines.
- On this day, the subjects will be admitted to the CRC.
- An 18 gauge intravenous catheter will be inserted in order to draw blood.
- The subjects will fast from 7 pm until after the next morning's testing.
- In the morning, while still supine after the overnight sleep, heart rate and blood pressure will be recorded, and blood will be drawn. The subjects will then stand for 10 minutes. Heart rate and blood pressure will be measured at intervals, and an upright blood sample will be collected.
- The subjects will be asked to collect their urine to end the 24hr urine collection. Another 24hr urine collection will be started.
- Treatment A (Carbidopa 200mg or placebo) will be given orally following the void, at approximately 7 am. Additional doses will be taken every 6 hours with the last dose at 7 am the following morning.
- Subjects will be free to follow their normal routine during the day until returning to the CRC for the night. However, they will need to consume the 200 mEq/day study diet for each meal, collect all urine, and take study medication on schedule
- After returning to the CRC, the subjects will fast after 7 pm.
- In the morning, supine and standing heart rate and blood pressure will be recorded, and the subjects will be asked to collect their urine to end the 24hr urine collection.
- The final dose of study medication (Carbidopa 200mg or placebo) will be given orally following the void, at approximately 7 am.
- Supine heart rate and blood pressure will be measured and supine blood samples will be collected hourly for 4 hours after the treatment and at 8 hours after the treatment. Subjects must rest supine for at least 30 minutes before each blood draw.
- At 2 hours after treatment, subjects will stand for 10 minutes for upright blood pressure and heart rate measurements and collection of an upright blood sample, as described above. Participants will be asked to rate the severity of common orthostatic symptoms while supine and upright.
- Urine will be collected for two 4-hour periods after treatment and from 8 hours to 24 hours after treatment.
- Fixed-sodium study diet will be provided after the 4-hour measurements and in the evening.
After at least a 1 day washout period, the study will be repeated with Treatment B
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Carbidopa then Placebo | Experimental | Drug: Carbidopa, Drug: PlaceboCarbidopa 200 mg every 6 hours orally for 5 doses followed by Placebo every 6 hours for 5 doses |
| Placebo then Carbidopa | Experimental | Drug: Carbidopa, Drug: PlaceboPlacebo matching carbidopa given every 6 hours orally for 5 doses followed by Carbidopa |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Patients diagnosed with POTS by the Vanderbilt Autonomic Dysfunction Center based on the following stringent criteria: 1) history of daily orthostatic symptoms for at least 6 months; 2) increase in heart rate (HR) of at least 30 bpm with standing or a standing HR of at least 120 bpm; 3) absence of orthostatic hypotension (defined as a fall in blood pressure (BP)>20/10 mm Hg); and 4) absence of conditions, such as dehydration, substantial weight loss, or systemic illnesses, that could provoke orthostatic intolerance
- Upright plasma NE at least 600 pg/mL in patients
- Non-smoking
- Free of medications with the potential to influence BP
- Able and willing to provide informed consent -
Key exclusion criteria (7 listed)
- Overt cause for postural tachycardia (such as acute dehydration)
- Significant cardiovascular, pulmonary, hepatic, or hematological disease by history or screening results
- Positive urine b-hcg pregnancy test
- Evidence of cardiac structural disease (by clinical examination or prior echocardiogram)
- Hypertension defined as a BP>145/95 (off medications) or need for antihypertensive medications
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 |
|---|---|---|
| Carbidopa200 mg every 6 hours for 5 doses given orally | Drug | Carbidopa then Placebo, Placebo then Carbidopa |
| Placeboevery 6 hours for 5 doses, given orally, and matching Carbidopa | Drug | Carbidopa then Placebo, Placebo then Carbidopa |
Primary outcome
24 Hour Urinary Sodium Excretion During Treatment Normalized to Creatinine
Time frame: Immediately before the 1st dose of placebo or carbidopa to immediately before the 5th dose (approximately 24 hours)
Urine was collected for 24hr during treatment. Urinary volume was measured and the urine was analyzed for sodium and creatinine concentrations. Total amounts of sodium and creatinine excreted over the 24 hr were calculated and results expressed as ratio of sodium:creatinine.
7 secondary outcomes
Systolic Blood Pressure Measured at 8 Hours After the Last Dose of Placebo or Carbidopa
Time frame: 8 hours after the last dose of placebo or carbidopa
Plasma Catecholamines (Norepinephrine) After the Last Dose of Placebo or Carbidopa
Time frame: 8 hours after the last dose of placebo or carbidopa
Plasma Catecholamines (DOPA) After the Last Dose of Placebo or Carbidopa
Time frame: 8 hours after the last dose of placebo or carbidopa
24 Hour Urinary Catecholamine (DOPA) Excretion During Treatment Normalized to Creatinine
Time frame: Immediately before the 1st dose of Placebo or Carbidopa and ending immediately before the last dose (approximately 24 hours)
24 Hour Urinary Catecholamine (Dopamine) Excretion During Treatment Normalized to Creatinine
Time frame: Immediately before the 1st dose of Placebo or Carbidopa and ending immediately before the last dose (approximately 24 hours)
Supine Plasma Renin Activity 2 Hours After the Last Dose of Placebo or Carbidopa
Time frame: 2 hours after the last dose of placebo or carbidopa
Plasma Sodium After the Last Dose of Placebo or Carbidopa
Time frame: 8 hours after the last dose of placebo or carbidopa
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Jan 2022.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 11566894Carey RM. Theodore Cooper Lecture: Renal dopamine system: paracrine regulator of sodium homeostasis and blood pressure. Hypertension. 2001 Sep;38(3):297-302. doi: 10.1161/hy0901.096422.
- Background: PubMed 2498027Goldstein DS, Stull R, Eisenhofer G, Gill JR Jr. Urinary excretion of dihydroxyphenylalanine and dopamine during alterations of dietary salt intake in humans. Clin Sci (Lond). 1989 May;76(5):517-22. doi: 10.1042/cs0760517.
- Background: PubMed 10981146Jose PA, Eisner GM, Felder RA. Renal dopamine and sodium homeostasis. Curr Hypertens Rep. 2000 Apr;2(2):174-83. doi: 10.1007/s11906-000-0079-y.
- Background: PubMed 710137Kuchel O, Buu NT, Unger T. Dopamine-sodium relationship: is dopamine a part of the endogenous natriuretic system? Contrib Nephrol. 1978;13:27-36. doi: 10.1159/000402132.
- Background: PubMed 9222944Stokes GS, Monaghan JC, Pillai DN. Effects of carbidopa and of intravenous saline infusion into normal and hypertensive subjects on urinary free and conjugated dopamine. J Hypertens. 1997 Jul;15(7):761-8. doi: 10.1097/00004872-199715070-00008.
- Background: PubMed 9274896Jacob G, Robertson D, Mosqueda-Garcia R, Ertl AC, Robertson RM, Biaggioni I; New Collective Author. Hypovolemia in syncope and orthostatic intolerance role of the renin-angiotensin system. Am J Med. 1997 Aug;103(2):128-33. doi: 10.1016/s0002-9343(97)00133-2.
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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.
Alfredo J Gamboa, MD principal investigator
Vanderbilt University Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Carbidopa in people with Postural Tachycardia Syndrome and Orthostatic Intolerance, run by Vanderbilt University at 1 site in United States.
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 7 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 24 Jan 2022. 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 United States. 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. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this combined 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.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 20 Sep 2021). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
24 Hour Urinary Sodium Excretion During Treatment Normalized to Creatinine (time frame: Immediately before the 1st dose of placebo or carbidopa to immediately before the 5th dose (approximately 24 hours)). 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 NCT00685919, which also lists 6 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 24 Jan 2022.