Neuropathic PainPhase 4NCT02246712
Influence of Diabetes on Tramadol Pharmacokinetics
A Phase 4 study testing Single oral dose of 100 mg racemic tramadol, CYP2D6 phenotype and CYP3A phenotype in people with Neuropathic Pain and Type 1 Diabetes Mellitus, run by Universidade Estadual Paulista Júlio de Mesquita Filho at 1 site in Brazil.
Trial summary
This study aimed to investigate the influence of uncontrolled type 1 and type 2 diabetes mellitus (DM) on the kinetic disposition, metabolism and pharmacokinetics-pharmacodynamics of tramadol enantiomers in patients with neuropathic pain. Read more about this study
- Who is it for?
- Ages 18 to 59 years
- Conditions the study is for
- Neuropathic Pain, Type 1 Diabetes Mellitus, Type 2 Diabetes Mellitus
- What is being tested?
- Single oral dose of 100 mg racemic tramadol, CYP2D6 phenotype and CYP3A phenotype
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteBrazil
- Study dates
- Jun 2008to Dec 2011
- Phase
- Phase 4
- 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 18 to 59 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Adult patients, both gender
- Patients with self-reported neuropathic pain (score >4 in a 0-10 visual analog scale)
- Patients with normal renal function (creatinine clearance >60 mL/min)
Who cannot join
- Patients with nociceptive somatic pain, visceral or autonomic associated during the study period;
- Patients with morbid obesity (BMI> 40), congestive heart failure, severe hypertension
- Patients who have had acute myocardial infarction or accident stroke less than 6 months of the period of investigation.
- Patients with chronic obstructive pulmonary disease
- Patients who were in use of analgesics, CYP2D6 inhibitors or CYP3A4 inducers or inhibitors were excluded.
- Pregnant and lactating patients were excluded.
Trial locations and contacts
1 site in 1 country.
Brazil1 site
Universidade Estadual Paulista Julio de Mesquita Filho
Araraquara, São Paulo, 14801902
About this study
Official title: Influence of Uncontrolled Diabetes on the Kinetic Disposition, Metabolism and Pharmacokinetics-pharmacodynamics of Tramadol Enantiomers in Patients With Neuropathic Pain
This study aimed to investigate the influence of uncontrolled type 1 and type 2 diabetes mellitus (DM) on the kinetic disposition, metabolism and pharmacokinetics-pharmacodynamics of tramadol enantiomers in patients with neuropathic pain. Thus, nondiabetic patients (control group, n = 12), patients with type 1 DM (n = 9), and patients with type 2 DM (n = 9), all with neuropathic pain and phenotyped as extensive metabolizers of cytochrome P450 2D6 (CYP2D6) who were treated with a single oral dose of 100 mg racemic tramadol were investigated.
Read the detailed description
Tramadol is a centrally acting analgesic that effectively relieves acute and chronic pain, including neuropathic pain in diabetic patients. The drug is available in clinical practice as a mixture of the (+)-tramadol and (-)-tramadol enantiomers. Tramadol is metabolized by CYP2D6 to O-desmethyltramadol (M1) and by cytochrome P450 3A (CYP3A4) and cytochrome P450 2B6 (CYP2B6) to N-desmethyltramadol (M2). Both tramadol enantiomers and (+)-M1 contribute to the analgesic activity of the drug: (+)-tramadol and the (+)-M1 metabolite act as -opioid receptor agonists; (+)-tramadol inhibits serotonin reuptake; and (-)-tramadol inhibits the reuptake of norepinephrine. This study investigated the influence of uncontrolled type 1 and type 2 diabetes mellitus (DM) on the kinetic disposition, metabolism and pharmacokinetics-pharmacodynamics of tramadol enantiomers in patients with neuropathic pain. Nondiabetic patients (control group, n = 12), patients with type 1 DM (n = 9), and patients with type 2 DM (n = 9), all with neuropathic pain and phenotyped as extensive metabolizers of CYP2D6, received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. The patients were evaluated for in vivo CYP3A activity using midazolam as a probe drug and genotyped for CYP2B6. Total and unbound plasma concentrations of the tramadol, M1 and M2 enantiomers were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS).
- Being tested
- Single oral dose of 100 mg racemic tramadol, CYP2D6 phenotype, CYP3A phenotype, CYP2B6 genotype
- Keywords
- tramadol, pharmacokinetics, enantiomers, metabolism, diabetes
- Medical subject headings
- Neuralgia, Diabetes Mellitus, Type 1, Diabetes Mellitus, Type 2, Diabetes Mellitus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Single oral dose of 100 mg racemic tramadolDrug
Also called Tramadol treament, Blood sampling, Tramadol pharmacokinetics
Serial blood samples were collected up to 24 h after drug administration; Pain was evaluated at the same time of blood sampling using visual analog scale
CYP2D6 phenotypeOther
Also called CYP2D6 phenotyping, CYP2D6 in vivo activity
Patients were phenotyped using metoprolol (100 mg, single oral dose). Urine was collected up to 8 hours after metoprolol administration. Urinary concentrations of metoprolol and alfa-hydroxymetoprolol were determined by high performance liquid chromatography (HPLC), using fluorescence detector.
CYP2D6 phenotyped was determined by alfa-hydroxymetoprolol/metoprolol urinary rato
CYP3A phenotypeOther
Also called CYP3A phenotyping, CYP3A in vivo activity
A single oral dose of midazolam (15 mg) was administered to all patients. Serial blood samples were collected up to 6 hours after the administration of midazolam.
The concentration of midazolam was determined in plasma in order to calculate midazolam clearance.
The in vivo activity of CYP3A was evaluated by midazolam oral clearance.
CYP2B6 genotypeGenetic
Also called Genotype of SNP 516G>T in CYP2B6
The single nucleotide polymorphism 516G>T in CYP2B6 gene was evaluated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).
| Study group | Role | What they receive |
|---|---|---|
| Control group | Active comparator | Patients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for the single nucleotide polymorphism (SNP) 516G>T in CYP2B6 gene (CYP2B6 genotype). Receives: Drug: Single oral dose of 100 mg racemic tramadol; Other: CYP2D6 phenotype; Other: CYP3A phenotype; Genetic: CYP2B6 genotype |
| T2DM group | Experimental | Patients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for SNP 516G>T in CYP2B6 gene (CYP2B6 genotype).
The diagnosis of type 2 DM was performed according to the American Diabetes Association (2010). Receives: Drug: Single oral dose of 100 mg racemic tramadol; Other: CYP2D6 phenotype; Other: CYP3A phenotype; Genetic: CYP2B6 genotype |
| T1DM group | Experimental | Patients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for SNP 516G>T in CYP2B6 gene (CYP2B6 genotype).
The diagnosis of type 1 DM was performed according to the American Diabetes Association (2010). Receives: Drug: Single oral dose of 100 mg racemic tramadol; Other: CYP2D6 phenotype; Other: CYP3A phenotype; Genetic: CYP2B6 genotype |
What is being measured
The primary outcome is the main question the study is designed to answer.
Kinetic parameters (AUC, Cmax, Tmax, apparent total clearance, and apparent volume of distribution) of tramadol enantiomers were estimated.
Measured: Up to 24h after a single oral dose of tramadol (100 mg)
Secondary outcomes (3)
Urinary concentration ratio (metoprolol/alfa-hydroxymetoprolol) as an in vivo measure of CYP2D6 activity
The CYP2D6 phenotype was determined by urinary concentration ratio metoprolol/alfa-hydroxymetoprolol
Measured: Up to 8h after metoprolol administration
Clearance of midazolam as a measure of CYP3A in vivo activity
Measured: Up to 6h after midazolam administration
Pain scores on the visual analog scale
Measured: Up to 24h after a single oral dose of tramadol (100 mg)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Sep 2014 (estimated)
- Study startJun 2008
- Primary completionMay 2010
- Study completionDec 2011
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Neuropathic PainStudies 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 4
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 30 participants (actual)
Sponsor and investigators
- Lead sponsor
- Universidade Estadual Paulista Júlio de Mesquita Filho
- Sponsor type
- University, hospital or other
- Collaborators
- University of Sao Paulo
- Responsible party
- Principal investigator, Natalia Valadares de Moraes, Universidade Estadual Paulista Júlio de Mesquita Filho
- Investigators
- Natalia V de Moraes, PhD, Principal investigator, Universidade Estadual Paulista Julio de Mesquita Filho
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02246712
- Sponsor's protocol ID
- DIABETRA
- Status last verified
- Sep 2014
- First submitted
- 16 Sep 2014
- Last updated
- 23 Sep 2014
- Results posted
- No
- Data monitoring committee
- No
Publications
de Moraes NV, Lauretti GR, Lanchote VL. Effects of type 1 and type 2 diabetes on the pharmacokinetics of tramadol enantiomers in patients with neuropathic pain phenotyped as cytochrome P450 2D6 extensive metabolizers. J Pharm Pharmacol. 2014 Sep;66(9):1222-30. doi: 10.1111/jphp.12255. Epub 2014 Apr 10.
PubMed 24717054de Moraes NV, Lauretti GR, Napolitano MN, Santos NR, Godoy AL, Lanchote VL. Enantioselective analysis of unbound tramadol, O-desmethyltramadol and N-desmethyltramadol in plasma by ultrafiltration and LC-MS/MS: application to clinical pharmacokinetics. J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jan 1;880(1):140-7. doi: 10.1016/j.jchromb.2011.11.033. Epub 2011 Nov 28.
PubMed 22173007
Study at a glance
From the registry record, last updated by the sponsor on 23 Sep 2014. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Influence of Uncontrolled Diabetes on the Kinetic Disposition, Metabolism and Pharmacokinetics-pharmacodynamics of Tramadol Enantiomers in Patients With Neuropathic Pain
- ClinicalTrials.gov ID
- NCT02246712
- Acronym / sponsor ID
- DIABETRA
- Keywords
- tramadol, pharmacokinetics, enantiomers, metabolism, diabetes
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 30 participants (actual)
- Lead sponsor
- Universidade Estadual Paulista Júlio de Mesquita FilhoUniversity, hospital or other
- Collaborators
- University of Sao Paulo
- Study start
- Jun 2008
- Primary completion
- May 2010 (actual)
- Study completion
- Dec 2011 (actual)
- First posted
- 23 Sep 2014 (estimated)
- 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.
This study aimed to investigate the influence of uncontrolled type 1 and type 2 diabetes mellitus (DM) on the kinetic disposition, metabolism and pharmacokinetics-pharmacodynamics of tramadol enantiomers in patients with neuropathic pain. Thus, nondiabetic patients (control group, n = 12), patients with type 1 DM (n = 9), and patients with type 2 DM (n = 9), all with neuropathic pain and phenotyped as extensive metabolizers of cytochrome P450 2D6 (CYP2D6) who were treated with a single oral dose of 100 mg racemic tramadol were investigated.
Detailed description
Tramadol is a centrally acting analgesic that effectively relieves acute and chronic pain, including neuropathic pain in diabetic patients. The drug is available in clinical practice as a mixture of the (+)-tramadol and (-)-tramadol enantiomers. Tramadol is metabolized by CYP2D6 to O-desmethyltramadol (M1) and by cytochrome P450 3A (CYP3A4) and cytochrome P450 2B6 (CYP2B6) to N-desmethyltramadol (M2). Both tramadol enantiomers and (+)-M1 contribute to the analgesic activity of the drug: (+)-tramadol and the (+)-M1 metabolite act as -opioid receptor agonists; (+)-tramadol inhibits serotonin reuptake; and (-)-tramadol inhibits the reuptake of norepinephrine. This study investigated the influence of uncontrolled type 1 and type 2 diabetes mellitus (DM) on the kinetic disposition, metabolism and pharmacokinetics-pharmacodynamics of tramadol enantiomers in patients with neuropathic pain. Nondiabetic patients (control group, n = 12), patients with type 1 DM (n = 9), and patients with type 2 DM (n = 9), all with neuropathic pain and phenotyped as extensive metabolizers of CYP2D6, received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. The patients were evaluated for in vivo CYP3A activity using midazolam as a probe drug and genotyped for CYP2B6. Total and unbound plasma concentrations of the tramadol, M1 and M2 enantiomers were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS).
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Control group | Active comparator | Drug: Single oral dose of 100 mg racemic tramadol, Other: CYP2D6 phenotype, Other: CYP3A phenotype, Genetic: CYP2B6 genotypePatients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for the single nucleotide polymorphism (SNP) 516G>T in CYP2B6 gene (CYP2B6 genotype). |
| T2DM group | Experimental | Drug: Single oral dose of 100 mg racemic tramadol, Other: CYP2D6 phenotype, Other: CYP3A phenotype, Genetic: CYP2B6 genotypePatients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for SNP 516G>T in CYP2B6 gene (CYP2B6 genotype). The diagnosis of type 2 DM was performed according to the American Diabetes Association (2010). |
| T1DM group | Experimental | Drug: Single oral dose of 100 mg racemic tramadol, Other: CYP2D6 phenotype, Other: CYP3A phenotype, Genetic: CYP2B6 genotypePatients received a single oral dose of 100 mg racemic tramadol. Serial blood samples were collected up to 24 h after administration of the drug for pharmacokinetic study and for the analysis of noradrenaline in plasma. Pain was rated on a visual analog pain scale at the same time as blood sampling. CYP2D6 phenotype was evaluated using metoprolol as probe drug. CYP3A phenotype was evaluated using midazolam. Patients were genotyped for SNP 516G>T in CYP2B6 gene (CYP2B6 genotype). The diagnosis of type 1 DM was performed according to the American Diabetes Association (2010). |
Who may qualify
- Ages
- 18 to 59 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Adult patients, both gender
- Patients with self-reported neuropathic pain (score >4 in a 0-10 visual analog scale)
- Patients with normal renal function (creatinine clearance >60 mL/min)
Key exclusion criteria (6 listed)
- Patients with nociceptive somatic pain, visceral or autonomic associated during the study period;
- Patients with morbid obesity (BMI> 40), congestive heart failure, severe hypertension
- Patients who have had acute myocardial infarction or accident stroke less than 6 months of the period of investigation.
- Patients with chronic obstructive pulmonary disease
- Patients who were in use of analgesics, CYP2D6 inhibitors or CYP3A4 inducers or inhibitors were excluded.
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 |
|---|---|---|
| Single oral dose of 100 mg racemic tramadolAlso: Tramadol treament, Blood sampling, Tramadol pharmacokineticsSerial blood samples were collected up to 24 h after drug administration; Pain was evaluated at the same time of blood sampling using visual analog scale | Drug | Control group, T1DM group, T2DM group |
| CYP2D6 phenotypeAlso: CYP2D6 phenotyping, CYP2D6 in vivo activityPatients were phenotyped using metoprolol (100 mg, single oral dose). Urine was collected up to 8 hours after metoprolol administration. Urinary concentrations of metoprolol and alfa-hydroxymetoprolol were determined by high performance liquid chromatography (HPLC), using fluorescence detector. CYP2D6 phenotyped was determined by alfa-hydroxymetoprolol/metoprolol urinary rato | Other | Control group, T1DM group, T2DM group |
| CYP3A phenotypeAlso: CYP3A phenotyping, CYP3A in vivo activityA single oral dose of midazolam (15 mg) was administered to all patients. Serial blood samples were collected up to 6 hours after the administration of midazolam. The concentration of midazolam was determined in plasma in order to calculate midazolam clearance. The in vivo activity of CYP3A was evaluated by midazolam oral clearance. | Other | Control group, T1DM group, T2DM group |
| CYP2B6 genotypeAlso: Genotype of SNP 516G>T in CYP2B6The single nucleotide polymorphism 516G>T in CYP2B6 gene was evaluated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). | Genetic | Control group, T1DM group, T2DM group |
Primary outcome
Kinetic parameters (AUC, Cmax, Tmax, apparent total clearance, and apparent volume of distribution) of tramadol enantiomers were estimated.
Time frame: Up to 24h after a single oral dose of tramadol (100 mg)
3 secondary outcomes
Urinary concentration ratio (metoprolol/alfa-hydroxymetoprolol) as an in vivo measure of CYP2D6 activity
Time frame: Up to 8h after metoprolol administration
Clearance of midazolam as a measure of CYP3A in vivo activity
Time frame: Up to 6h after midazolam administration
Pain scores on the visual analog scale
Time frame: Up to 24h after a single oral dose of tramadol (100 mg)
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 23 Sep 2014.
- Results publication: PubMed 24717054de Moraes NV, Lauretti GR, Lanchote VL. Effects of type 1 and type 2 diabetes on the pharmacokinetics of tramadol enantiomers in patients with neuropathic pain phenotyped as cytochrome P450 2D6 extensive metabolizers. J Pharm Pharmacol. 2014 Sep;66(9):1222-30. doi: 10.1111/jphp.12255. Epub 2014 Apr 10.
- Results publication: PubMed 22173007de Moraes NV, Lauretti GR, Napolitano MN, Santos NR, Godoy AL, Lanchote VL. Enantioselective analysis of unbound tramadol, O-desmethyltramadol and N-desmethyltramadol in plasma by ultrafiltration and LC-MS/MS: application to clinical pharmacokinetics. J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jan 1;880(1):140-7. doi: 10.1016/j.jchromb.2011.11.033. Epub 2011 Nov 28.
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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.
Natalia V de Moraes, PhD principal investigator
Universidade Estadual Paulista Julio de Mesquita Filho
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Single oral dose of 100 mg racemic tramadol, CYP2D6 phenotype and CYP3A phenotype in people with Neuropathic Pain and Type 1 Diabetes Mellitus, run by Universidade Estadual Paulista Júlio de Mesquita Filho at 1 site in Brazil.
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 23 Sep 2014. 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 Brazil. 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 phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
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?
Kinetic parameters (AUC, Cmax, Tmax, apparent total clearance, and apparent volume of distribution) of tramadol enantiomers were estimated. (time frame: Up to 24h after a single oral dose of tramadol (100 mg)). 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 NCT02246712, which also lists 2 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 23 Sep 2014.