CYP1A2 PolymorphismNCT04240496
Clinical and Genetic Influencing Factors on Clozapine Pharmacokinetics
A study testing Determination of plasma concentration of clozapine/ Genotyping in people with CYP1A2 Polymorphism and CYP2C19 Polymorphism, run by University of Monastir at 1 site in Tunisia.
Trial summary
Clozapine (Clz), an atypical antipsychotic, is the reference medication for patients with treatment-resistant schizophrenia. Due to the high inter-individual variability of its pharmacokinetics and its narrow therapeutic index, a close therapeutic drug monitoring (TDM) of Clz is highly recommended. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- CYP1A2 Polymorphism, CYP2C19 Polymorphism, Clozapine
- What is being tested?
- Determination of plasma concentration of clozapine/ Genotyping
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 51 participants
- Where
- 1 siteTunisia
- Study dates
- 17 Oct 2019to 14 Dec 2019
- Phase
- Interventional
- 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 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Schizophrenic patients receiving clozapine
- Good adherence to the treatment (clozapine)
Who cannot join
- Patients who were co-prescribed drugs that affected the pharmacokinetics of Clozapine.
- Patients who presented gastrointestinal disorders disturbing absorption of clozapine.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Clinical and Genetic Influencing Factors on Clozapine Pharmacokinetics in Schizophrenic Patients
Clozapine (Clz), an atypical antipsychotic, is the reference medication for patients with treatment-resistant schizophrenia. Due to the high inter-individual variability of its pharmacokinetics and its narrow therapeutic index, a close therapeutic drug monitoring (TDM) of Clz is highly recommended.
Several factors can cause a variation in the pharmacokinetics as age, smoking habits, coffee consumption and drug interaction. Genetic factors related to hepatic expression levels of the cytochrome P450 (CYP), regulate the hepatic clearance of Clz, thereby determine its bioavailability.
Read more
The CYP1A2 and CYP2C19 isoenzymes are mainly responsible for the metabolism of several drugs including Clz. It has been demonstrated that there is an interethnic variation in the expression and function of these two isoenzymes. This variation is caused by single nucleotide polymorphisms (SNPs) of genes encoding these proteins.
While the Influence of the different polymorphisms related to CYP1A2 and CYP2C19 have been established especially in Asian and Caucasian populations, no study has examined the impact of these SNPs in the southern Mediterranean populations. Moreover, the impact of these SNPs is very controversial. The present study aims to investigate in Tunisian schizophrenic patients, the influence of genetic (CYP1A2 and CYP2C19 polymorphisms) and non-genetic factors on Clz pharmacokinetics.
- Conditions
- CYP1A2 Polymorphism, CYP2C19 Polymorphism, Clozapine, Schizophrenia
- Being tested
- Determination of plasma concentration of clozapine/ Genotyping
- Medical subject headings
- Schizophrenia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Determination of plasma concentration of clozapine/ GenotypingOther
Determination of trough plasma concentration of clozapine (C0) Genotyping of CYP1A2 \& CYP2C19
| Study group | Role | What they receive |
|---|---|---|
| Schizophrenic patients | Other | * Determination of trough plasma concentration of clozapine (C0)
* Genotyping of CYP1A2 \& CYP2C19 Drug: Leponex (Clozapine) : was started at a dose of 25 mg/j, the dose was gradually increased and was administered in one, two or three divided doses. Receives: Other: Determination of plasma concentration of clozapine/ Genotyping |
What is being measured
The primary outcome is the main question the study is designed to answer.
Determination of trough plasma concentration of clozapine (C0)
Technique : HPLC/UV (high-performance liquid chromatography associated with a UV detector)
Measured: One and a half months
Secondary outcomes (1)
Determination of the correlation between the presence of CYP1A2*1F (rs762551;-163C> A), CYP1A2*1C (rs2069514;-3860 G> A) and CYP 2C19*2 (rs4244285; 681G>A) and the variability of C0/Daily dose.
- Technique: PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism)
Measured: One and a half months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jan 2020
- Study start17 Oct 2019
- Primary completion14 Dec 2019
- Study completion14 Dec 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for CYP1A2 PolymorphismStudies 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 N/A
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 51 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Monastir
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dr. Helmi AMMAR, University of Monastir
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04240496
- Sponsor's protocol ID
- IORG 0009738 N°30
- Status last verified
- Jan 2020
- First submitted
- 16 Jan 2020
- Last updated
- 27 Jan 2020
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Jan 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clinical and Genetic Influencing Factors on Clozapine Pharmacokinetics in Schizophrenic Patients
- ClinicalTrials.gov ID
- NCT04240496
- Acronym / sponsor ID
- IORG 0009738 N°30
- Conditions
- CYP1A2 Polymorphism, CYP2C19 Polymorphism, Clozapine, Schizophrenia
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 51 participants (actual)
- Lead sponsor
- University of MonastirUniversity, hospital or other
- Study start
- 17 Oct 2019 (actual)
- Primary completion
- 14 Dec 2019 (actual)
- Study completion
- 14 Dec 2019 (actual)
- First posted
- 27 Jan 2020 (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.
Clozapine (Clz), an atypical antipsychotic, is the reference medication for patients with treatment-resistant schizophrenia. Due to the high inter-individual variability of its pharmacokinetics and its narrow therapeutic index, a close therapeutic drug monitoring (TDM) of Clz is highly recommended.
Several factors can cause a variation in the pharmacokinetics as age, smoking habits, coffee consumption and drug interaction. Genetic factors related to hepatic expression levels of the cytochrome P450 (CYP), regulate the hepatic clearance of Clz, thereby determine its bioavailability.
The CYP1A2 and CYP2C19 isoenzymes are mainly responsible for the metabolism of several drugs including Clz. It has been demonstrated that there is an interethnic variation in the expression and function of these two isoenzymes. This variation is caused by single nucleotide polymorphisms (SNPs) of genes encoding these proteins.
While the Influence of the different polymorphisms related to CYP1A2 and CYP2C19 have been established especially in Asian and Caucasian populations, no study has examined the impact of these SNPs in the southern Mediterranean populations. Moreover, the impact of these SNPs is very controversial. The present study aims to investigate in Tunisian schizophrenic patients, the influence of genetic (CYP1A2 and CYP2C19 polymorphisms) and non-genetic factors on Clz pharmacokinetics.
Study design
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Schizophrenic patients | Other | Other: Determination of plasma concentration of clozapine/ Genotyping* Determination of trough plasma concentration of clozapine (C0) * Genotyping of CYP1A2 \& CYP2C19 Drug: Leponex (Clozapine) : was started at a dose of 25 mg/j, the dose was gradually increased and was administered in one, two or three divided doses. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Schizophrenic patients receiving clozapine
- Good adherence to the treatment (clozapine)
Key exclusion criteria (2 listed)
- Patients who were co-prescribed drugs that affected the pharmacokinetics of Clozapine.
- Patients who presented gastrointestinal disorders disturbing absorption of clozapine.
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 |
|---|---|---|
| Determination of plasma concentration of clozapine/ GenotypingDetermination of trough plasma concentration of clozapine (C0) Genotyping of CYP1A2 \& CYP2C19 | Other | Schizophrenic patients |
Primary outcome
Determination of trough plasma concentration of clozapine (C0)
Time frame: One and a half months
Technique : HPLC/UV (high-performance liquid chromatography associated with a UV detector)
1 secondary outcome
Determination of the correlation between the presence of CYP1A2*1F (rs762551;-163C> A), CYP1A2*1C (rs2069514;-3860 G> A) and CYP 2C19*2 (rs4244285; 681G>A) and the variability of C0/Daily dose.
Time frame: One and a half months
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 27 Jan 2020.
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.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Determination of plasma concentration of clozapine/ Genotyping in people with CYP1A2 Polymorphism and CYP2C19 Polymorphism, run by University of Monastir at 1 site in Tunisia.
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 2 inclusion and 2 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 27 Jan 2020. 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 Tunisia. 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?
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?
Determination of trough plasma concentration of clozapine (C0) (time frame: One and a half months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 27 Jan 2020.