Abdominal SurgeryMETRASNCT04004481
Metabolites of Tramadol in the Postoperative Surgical Patients
An observational study of Abdominal Surgery and Respiratory Failure, run by Osijek University Hospital at 1 site in Croatia.
Trial summary
Tramadol is opioid analgesic widely used to treat moderate to severe pain. It is metabolized by cytochrome CYP2D6 into two major metabolites: pharmacologically active metabolite O-desmethyltramadol (M1) and inactive N-desmethyltramadol (M2), respectively. Read more about this study
- Who is it for?
- Ages 18 to 90 years
- Conditions the study is for
- Abdominal Surgery, Respiratory Failure, Renal Failure
- What is being tested?
- Postoperative analgesia using tramadol
- How many people
- 50 participants
- Where
- 1 siteCroatia
- Study dates
- 25 Jan 2019to 13 Mar 2020
- Phase
- Observational
- 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 90 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: The patients undergoing major open abdominal cancer surgery in Osijek University Hospital who are admitted in the ICU after surgery, age between 18 and 90 years, BMI >18 and <35, who signed the informed consent will be included in the study.
Who may be able to join
- patients after major abdominal surgery will be observed.
- surgical interventions requiring a laparotomy and involving resection of the organs of the digestive system
- postoperative ICU admission.
Who cannot join
- allergic reaction to tramadol
- patients under 18 years old
- patient over 90 years old
- BMI <18 and >35
- laparoscopic surgery
- chronic therapy with tramadol, cimetidine, paroxetine, pimozide, metoclopramide, amiodarone, olanzapine, chlorpromazine, fluphenazine, haloperidol, thioridazine, risperidone and clozapine
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Metabolites of Tramadol in the Postoperative Surgical Patients Admitted in the ICU
Tramadol is opioid analgesic widely used to treat moderate to severe pain. It is metabolized by cytochrome CYP2D6 into two major metabolites: pharmacologically active metabolite O-desmethyltramadol (M1) and inactive N-desmethyltramadol (M2), respectively. Tramadol kinetics in a population of patients undergoing major abdominal surgical procedures, and in patients with a greater or lesser degree of organic failure, is still not well researched. The investigators will measure plasma concentrations of tramadol and its metabolites after usual tramadol doses in ICU patients after major abdominal surgery. Also analgesic affect and side effect of tramadol will be recorded.
Read the detailed description
The blood samples for the CYP2D6 gene polymorphism analysis will be taken from all patients included in the study. The patients will be categorized as slow (PM), normal (NM) or ultra-fast metabolizers (UM) of tramadol using analysis of the CYP2D6 phenotype. Standard laboratory findings including red blood cells, urea, creatinine, and cholinesterase will be done before surgery.
The patients will receive 500 mg of tramadol intravenously divided into 5 doses during the first 24 postoperative hours in the ICU. The plasma concentrations of tramadol, O-desmethyltramadol and N-desmethyltramadol will be measured 1, 2 and 4 hours after the first dose, and immediately before the 2nd, 3rd and 5th dose. There will therefore be 6 measurements of tramadol and its metabolites.
The analgesic effect of tramadol will be measured in awake patients with Numeric Rating Scale - NRS (0 - without pain, 10 - strong pain) 30 minutes before and 30 minutes after tramadol administration. The NRS value of 3 or less will be considered as adequate analgesia. In case of inadequate analgesia rescue analgesic (morphine) will be used according to the local protocol.
In unconscious patients the analgesic effect of tramadol will be tested by Critical Care Pain Observation Tool (CPOT). The CPOT value of less than 2 will be considered as adequate analgesia. In case of inadequate analgesia rescue analgesic (morphine) will be used according to the local protocol. During the first 24 hours side effect of tramadol, such as nausea, vomiting and new respiratory depression will be recorded.
- Conditions
- Abdominal Surgery, Respiratory Failure, Renal Failure, Liver Dysfunction, Multiorgan Failure
- Being tested
- Postoperative analgesia using tramadol
- Keywords
- Tramadol, CYP2D6 polymorphism, analgesia, intensive care, organ failure
- Medical subject headings
- Respiratory Insufficiency, Renal Insufficiency, Liver Diseases, Multiple Organ Failure, Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Postoperative analgesia using tramadolDrug
Also called Morphine for rescue analgesia
Tramadol 100 mg will be given to the patients in the postoperative period.
| Study group | Role | What they receive |
|---|---|---|
| Adult patients undergoing major open abdominal surgery | Observational study. In the patients undergoing major open abdominal surgery for cancer tramadol will be used for postoperative analgesia. In the postoperative period parent compound and metabolites of tramadol will be measured. Postoperative analgesia and adverse effects will be registered and compared between CYP2D6 phenotypes observed. Receives: Drug: Postoperative analgesia using tramadol |
What is being measured
The primary outcome is the main question the study is designed to answer.
Serum Concentration of Tramadol and Tramadol Metabolites With Respect to Metabolic Phenotype
The plasma concentrations of tramadol, O-desmethyltramadol (ODT) and N-desmethyltramadol (NDT) will be measured 1, 2 and 4 hours after the first dose of 100 mg tramadol i.v., and immediately before the 2nd, 3rd and 5th dose. There will therefore be 6 measurements of tramadol and its metabolites.
Measured: 1, 2, and 4 hours after first dose and immediately before 2nd, 3rd, and 5th dose, up to 24 hours
Secondary outcomes (5)
Analgesic Effect of Tramadol Measured by Numeric Rating Scale (NRS)
The analgesic effect of tramadol will be measured in awake patients with Numeric Rating Scale (NRS, 0 - without pain, 10 - the worst pain) 30 minutes before and 30 minutes after tramadol administration. The NRS value of 3 or less will be considered as adequate analgesia. In case of inadequate analgesia morphine will be used according to the local protocol.
Measured: Before each dose of tramadol and 30 minutes after tramadol dose, up to 24 hours
Analgesic Effect of Tramadol Measured by Critical Care Pain Observation Tool (CPOT)
In unconsciousness patents, the analgesic effect of tramadol will be tested by Critical Care Pain Observation Tool (CPOT). Highest score on a scale is 8 (worst pain) and lowest is 0 (no pain). The CPOT value of less than 2 will be considered as adequate analgesia.
Measured: Pain was assessed before and 30 minutes after each tramadol dose, up to 24 hours.
Number of Participants With Nausea and Vomiting After Tramadol
Nausea and/or vomiting during treatment with tramadol in ICU will be recorded.
Measured: Nausea and vomiting was assessed during first 30 minutes after tramadol administration
Number of Patients With Respiratory Depression After Tramadol
Respiratory depression after tramadol is considered to be any drop in saturation below 90% or drop in respiratory rate below 10/min.
Measured: Respiratory depression was observed up to 30 minutes after tramadol administration
Length of ICU Stay
Length of stay in ICU will be recorded and correlated with standard laboratory values and tramadol and metabolites concentration.
Measured: Up to 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jul 2019
- Study start25 Jan 2019
- Primary completion28 Feb 2020
- Study completion13 Mar 2020
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 (11)Papers the sponsor has linked to this study.
- Other trials for Abdominal SurgeryStudies 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 50 participants (actual)
Sponsor and investigators
- Lead sponsor
- Osijek University Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Josip Juraj Strossmayer University of Osijek
- Responsible party
- Sponsor
- Investigators
- Nenad Neskovic, MD, Principal investigator, Osijek University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04004481
- Sponsor's protocol ID
- OsijekUH
- Acronym
- METRAS
- Status last verified
- Jun 2021
- First submitted
- 25 Jun 2019
- Last updated
- 9 Jul 2021
- Results posted
- Yes, on ClinicalTrials.gov
- Individual data sharing
- Undecided
Publications
Yang Y, Botton MR, Scott ER, Scott SA. Sequencing the CYP2D6 gene: from variant allele discovery to clinical pharmacogenetic testing. Pharmacogenomics. 2017 May;18(7):673-685. doi: 10.2217/pgs-2017-0033. Epub 2017 May 4.
PubMed 28470112Qiao W, Yang Y, Sebra R, Mendiratta G, Gaedigk A, Desnick RJ, Scott SA. Long-Read Single Molecule Real-Time Full Gene Sequencing of Cytochrome P450-2D6. Hum Mutat. 2016 Mar;37(3):315-23. doi: 10.1002/humu.22936. Epub 2015 Dec 18.
PubMed 26602992Grond S, Sablotzki A. Clinical pharmacology of tramadol. Clin Pharmacokinet. 2004;43(13):879-923. doi: 10.2165/00003088-200443130-00004.
PubMed 15509185de Moraes NV, Lauretti GR, Coelho EB, Godoy AL, Neves DV, Lanchote VL. Impact of fraction unbound, CYP3A, and CYP2D6 in vivo activities, and other potential covariates to the clearance of tramadol enantiomers in patients with neuropathic pain. Fundam Clin Pharmacol. 2016 Apr;30(2):153-61. doi: 10.1111/fcp.12168. Epub 2015 Dec 11.
PubMed 26947771Xu J, Zhang XC, Lv XQ, Xu YY, Wang GX, Jiang B, Cai L, Cai XJ. Effect of the cytochrome P450 2D6*10 genotype on the pharmacokinetics of tramadol in post-operative patients. Pharmazie. 2014 Feb;69(2):138-41.
PubMed 24640604Stamer UM, Musshoff F, Kobilay M, Madea B, Hoeft A, Stuber F. Concentrations of tramadol and O-desmethyltramadol enantiomers in different CYP2D6 genotypes. Clin Pharmacol Ther. 2007 Jul;82(1):41-7. doi: 10.1038/sj.clpt.6100152. Epub 2007 Mar 14.
PubMed 17361124Candiotti KA, Birnbach DJ, Lubarsky DA, Nhuch F, Kamat A, Koch WH, Nikoloff M, Wu L, Andrews D. The impact of pharmacogenomics on postoperative nausea and vomiting: do CYP2D6 allele copy number and polymorphisms affect the success or failure of ondansetron prophylaxis? Anesthesiology. 2005 Mar;102(3):543-9. doi: 10.1097/00000542-200503000-00011.
PubMed 15731591Bosilkovska M, Walder B, Besson M, Daali Y, Desmeules J. Analgesics in patients with hepatic impairment: pharmacology and clinical implications. Drugs. 2012 Aug 20;72(12):1645-69. doi: 10.2165/11635500-000000000-00000.
PubMed 22867045Rijkenberg S, Stilma W, Bosman RJ, van der Meer NJ, van der Voort PHJ. Pain Measurement in Mechanically Ventilated Patients After Cardiac Surgery: Comparison of the Behavioral Pain Scale (BPS) and the Critical-Care Pain Observation Tool (CPOT). J Cardiothorac Vasc Anesth. 2017 Aug;31(4):1227-1234. doi: 10.1053/j.jvca.2017.03.013. Epub 2017 Mar 15.
PubMed 28800982Severgnini P, Pelosi P, Contino E, Serafinelli E, Novario R, Chiaranda M. Accuracy of Critical Care Pain Observation Tool and Behavioral Pain Scale to assess pain in critically ill conscious and unconscious patients: prospective, observational study. J Intensive Care. 2016 Nov 7;4:68. doi: 10.1186/s40560-016-0192-x. eCollection 2016.
PubMed 27833752Neskovic N, Mandic D, Marczi S, Skiljic S, Kristek G, Vinkovic H, Mraovic B, Debeljak Z, Kvolik S. Different Pharmacokinetics of Tramadol, O-Demethyltramadol and N-Demethyltramadol in Postoperative Surgical Patients From Those Observed in Medical Patients. Front Pharmacol. 2021 Apr 15;12:656748. doi: 10.3389/fphar.2021.656748. eCollection 2021.
PubMed 33935773
Study at a glance
From the registry record, last updated by the sponsor on 9 Jul 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Metabolites of Tramadol in the Postoperative Surgical Patients Admitted in the ICU
- ClinicalTrials.gov ID
- NCT04004481
- Acronym / sponsor ID
- METRAS / OsijekUH
- Conditions
- Abdominal Surgery, Respiratory Failure, Renal Failure, Liver Dysfunction, Multiorgan Failure
- Keywords
- Tramadol, CYP2D6 polymorphism, analgesia, intensive care, organ failure
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 50 participants (actual)
- Lead sponsor
- Osijek University HospitalUniversity, hospital or other
- Collaborators
- Josip Juraj Strossmayer University of Osijek
- Study start
- 25 Jan 2019 (actual)
- Primary completion
- 28 Feb 2020 (actual)
- Study completion
- 13 Mar 2020 (actual)
- First posted
- 2 Jul 2019 (actual)
- Results
- Posted 9 Jul 2021
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Tramadol is opioid analgesic widely used to treat moderate to severe pain. It is metabolized by cytochrome CYP2D6 into two major metabolites: pharmacologically active metabolite O-desmethyltramadol (M1) and inactive N-desmethyltramadol (M2), respectively. Tramadol kinetics in a population of patients undergoing major abdominal surgical procedures, and in patients with a greater or lesser degree of organic failure, is still not well researched. The investigators will measure plasma concentrations of tramadol and its metabolites after usual tramadol doses in ICU patients after major abdominal surgery. Also analgesic affect and side effect of tramadol will be recorded.
Detailed description
The blood samples for the CYP2D6 gene polymorphism analysis will be taken from all patients included in the study. The patients will be categorized as slow (PM), normal (NM) or ultra-fast metabolizers (UM) of tramadol using analysis of the CYP2D6 phenotype. Standard laboratory findings including red blood cells, urea, creatinine, and cholinesterase will be done before surgery.
The patients will receive 500 mg of tramadol intravenously divided into 5 doses during the first 24 postoperative hours in the ICU. The plasma concentrations of tramadol, O-desmethyltramadol and N-desmethyltramadol will be measured 1, 2 and 4 hours after the first dose, and immediately before the 2nd, 3rd and 5th dose. There will therefore be 6 measurements of tramadol and its metabolites.
The analgesic effect of tramadol will be measured in awake patients with Numeric Rating Scale - NRS (0 - without pain, 10 - strong pain) 30 minutes before and 30 minutes after tramadol administration. The NRS value of 3 or less will be considered as adequate analgesia. In case of inadequate analgesia rescue analgesic (morphine) will be used according to the local protocol.
In unconscious patients the analgesic effect of tramadol will be tested by Critical Care Pain Observation Tool (CPOT). The CPOT value of less than 2 will be considered as adequate analgesia. In case of inadequate analgesia rescue analgesic (morphine) will be used according to the local protocol. During the first 24 hours side effect of tramadol, such as nausea, vomiting and new respiratory depression will be recorded.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Adult patients undergoing major open abdominal surgery | – | Drug: Postoperative analgesia using tramadolObservational study. In the patients undergoing major open abdominal surgery for cancer tramadol will be used for postoperative analgesia. In the postoperative period parent compound and metabolites of tramadol will be measured. Postoperative analgesia and adverse effects will be registered and compared between CYP2D6 phenotypes observed. |
Who may qualify
- Ages
- 18 to 90 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The patients undergoing major open abdominal cancer surgery in Osijek University Hospital who are admitted in the ICU after surgery, age between 18 and 90 years, BMI >18 and <35, who signed the informed consent will be included in the study.
Key inclusion criteria (3 listed)
- patients after major abdominal surgery will be observed.
- surgical interventions requiring a laparotomy and involving resection of the organs of the digestive system
- postoperative ICU admission.
Key exclusion criteria (6 listed)
- allergic reaction to tramadol
- patients under 18 years old
- patient over 90 years old
- BMI <18 and >35
- laparoscopic surgery
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 |
|---|---|---|
| Postoperative analgesia using tramadolAlso: Morphine for rescue analgesiaTramadol 100 mg will be given to the patients in the postoperative period. | Drug | Adult patients undergoing major open abdominal surgery |
Primary outcome
Serum Concentration of Tramadol and Tramadol Metabolites With Respect to Metabolic Phenotype
Time frame: 1, 2, and 4 hours after first dose and immediately before 2nd, 3rd, and 5th dose, up to 24 hours
The plasma concentrations of tramadol, O-desmethyltramadol (ODT) and N-desmethyltramadol (NDT) will be measured 1, 2 and 4 hours after the first dose of 100 mg tramadol i.v., and immediately before the 2nd, 3rd and 5th dose. There will therefore be 6 measurements of tramadol and its metabolites.
5 secondary outcomes
Analgesic Effect of Tramadol Measured by Numeric Rating Scale (NRS)
Time frame: Before each dose of tramadol and 30 minutes after tramadol dose, up to 24 hours
Analgesic Effect of Tramadol Measured by Critical Care Pain Observation Tool (CPOT)
Time frame: Pain was assessed before and 30 minutes after each tramadol dose, up to 24 hours.
Number of Participants With Nausea and Vomiting After Tramadol
Time frame: Nausea and vomiting was assessed during first 30 minutes after tramadol administration
Number of Patients With Respiratory Depression After Tramadol
Time frame: Respiratory depression was observed up to 30 minutes after tramadol administration
Length of ICU Stay
Time frame: Up to 6 months
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Jul 2021.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 28470112Yang Y, Botton MR, Scott ER, Scott SA. Sequencing the CYP2D6 gene: from variant allele discovery to clinical pharmacogenetic testing. Pharmacogenomics. 2017 May;18(7):673-685. doi: 10.2217/pgs-2017-0033. Epub 2017 May 4.
- Background: PubMed 26602992Qiao W, Yang Y, Sebra R, Mendiratta G, Gaedigk A, Desnick RJ, Scott SA. Long-Read Single Molecule Real-Time Full Gene Sequencing of Cytochrome P450-2D6. Hum Mutat. 2016 Mar;37(3):315-23. doi: 10.1002/humu.22936. Epub 2015 Dec 18.
- Background: PubMed 15509185Grond S, Sablotzki A. Clinical pharmacology of tramadol. Clin Pharmacokinet. 2004;43(13):879-923. doi: 10.2165/00003088-200443130-00004.
- Background: PubMed 26947771de Moraes NV, Lauretti GR, Coelho EB, Godoy AL, Neves DV, Lanchote VL. Impact of fraction unbound, CYP3A, and CYP2D6 in vivo activities, and other potential covariates to the clearance of tramadol enantiomers in patients with neuropathic pain. Fundam Clin Pharmacol. 2016 Apr;30(2):153-61. doi: 10.1111/fcp.12168. Epub 2015 Dec 11.
- Background: PubMed 24640604Xu J, Zhang XC, Lv XQ, Xu YY, Wang GX, Jiang B, Cai L, Cai XJ. Effect of the cytochrome P450 2D6*10 genotype on the pharmacokinetics of tramadol in post-operative patients. Pharmazie. 2014 Feb;69(2):138-41.
- Background: PubMed 17361124Stamer UM, Musshoff F, Kobilay M, Madea B, Hoeft A, Stuber F. Concentrations of tramadol and O-desmethyltramadol enantiomers in different CYP2D6 genotypes. Clin Pharmacol Ther. 2007 Jul;82(1):41-7. doi: 10.1038/sj.clpt.6100152. Epub 2007 Mar 14.
- Background: PubMed 15731591Candiotti KA, Birnbach DJ, Lubarsky DA, Nhuch F, Kamat A, Koch WH, Nikoloff M, Wu L, Andrews D. The impact of pharmacogenomics on postoperative nausea and vomiting: do CYP2D6 allele copy number and polymorphisms affect the success or failure of ondansetron prophylaxis? Anesthesiology. 2005 Mar;102(3):543-9. doi: 10.1097/00000542-200503000-00011.
- Background: PubMed 22867045Bosilkovska M, Walder B, Besson M, Daali Y, Desmeules J. Analgesics in patients with hepatic impairment: pharmacology and clinical implications. Drugs. 2012 Aug 20;72(12):1645-69. doi: 10.2165/11635500-000000000-00000.
- Background: PubMed 28800982Rijkenberg S, Stilma W, Bosman RJ, van der Meer NJ, van der Voort PHJ. Pain Measurement in Mechanically Ventilated Patients After Cardiac Surgery: Comparison of the Behavioral Pain Scale (BPS) and the Critical-Care Pain Observation Tool (CPOT). J Cardiothorac Vasc Anesth. 2017 Aug;31(4):1227-1234. doi: 10.1053/j.jvca.2017.03.013. Epub 2017 Mar 15.
- Background: PubMed 27833752Severgnini P, Pelosi P, Contino E, Serafinelli E, Novario R, Chiaranda M. Accuracy of Critical Care Pain Observation Tool and Behavioral Pain Scale to assess pain in critically ill conscious and unconscious patients: prospective, observational study. J Intensive Care. 2016 Nov 7;4:68. doi: 10.1186/s40560-016-0192-x. eCollection 2016.
- Derived from this study: PubMed 33935773Neskovic N, Mandic D, Marczi S, Skiljic S, Kristek G, Vinkovic H, Mraovic B, Debeljak Z, Kvolik S. Different Pharmacokinetics of Tramadol, O-Demethyltramadol and N-Demethyltramadol in Postoperative Surgical Patients From Those Observed in Medical Patients. Front Pharmacol. 2021 Apr 15;12:656748. doi: 10.3389/fphar.2021.656748. eCollection 2021.
- Individual participant dataSharing planned: Undecided
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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.
Nenad Neskovic, MD principal investigator
Osijek University Hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Abdominal Surgery and Respiratory Failure, run by Osijek University Hospital at 1 site in Croatia.
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 3 inclusion and 6 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 9 Jul 2021. 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 Croatia. 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.
Are results available for this study?
Yes. Results are posted in the registry (first posted 9 Jul 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?
Serum Concentration of Tramadol and Tramadol Metabolites With Respect to Metabolic Phenotype (time frame: 1, 2, and 4 hours after first dose and immediately before 2nd, 3rd, and 5th dose, up to 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 NCT04004481, which also lists 11 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 9 Jul 2021.