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Interaction of CYP2B6 Genotype and Efavirenz With Methadone and Tizanidine PK
NCT05789173 · View on ClinicalTrials.gov ↗
Study Summary
The main goal of this clinical study is to test how CYP2B6 genetic variations and efavirenz (cornerstone in HIV-1 therapy) dictate the disposition (PK) of CYP2B6 substrate (methadone) and PK and effect (PD) of CYP1A2 substrate (tizanidine). Specifically, the investigators will test whether efavirenz produces CYP2B6 genotype dependent unanticipated DDIs with CYP2B6 (methadone) and CYP1A2 (tizanidine), leading to lack of efficacy or increased toxicity. Healthy volunteers genotyped for CYP2B6\*6 and \*18 alleles will be grouped in to three genotype predicted phenotype groups: 20 normal metabolizer (NM) (CYP2B6\*1/\*1); 20 intermediate metabolizer (IM) (\*1/\*6, or \*1/\*18); and 20 poor metabolizer (PM) (\*6/\*6, \*6/\*18 or \*18/\*18). Each phenotype group will receive methadone and tizanidine (separated by a washout period) on two occasions: at baseline (control) and after treatment with efavirenz (600 mg/day for 17 days).
Conditions Studied
Interventions
- DRUG Methadone and Tizanidine
- DRUG Efavirenz, Methadone and Tizanidine
Study Locations (1)
Indiana
- Indiana University School of Medicine — Indianapolis
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 60 participants |
| Start Date | 2023-10-06 |
| Est. Completion | 2026-04-15 |
| Phase | Early Phase 1 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT05789173
The ClinicalTrials.gov registry entry for NCT05789173 describes a study currently listed as recruiting. It is categorized as Early Phase 1, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 60 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Indiana University, which has 1,026 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Drug-Drug Interaction appearing as the primary indexed condition, and to 2 interventions — of which Methadone and Tizanidine is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT05789173 reports 1 study location spanning 1 distinct geographic area — top geographies include Indiana. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT05789173 about?
NCT05789173 is a clinical study titled "Interaction of CYP2B6 Genotype and Efavirenz With Methadone and Tizanidine PK". The main goal of this clinical study is to test how CYP2B6 genetic variations and efavirenz (cornerstone in HIV-1 therapy) dictate the disposition (PK) of CYP2B6 substrate (methadone) and PK and effect (PD) of CYP1A2 substrate (tizanidine). Specifically, the investigators will test whether efavirenz...
What is the current status of trial NCT05789173?
This trial is currently recruiting. It is a Early Phase 1 study. The enrollment target is 60 participants. The study started on 2023-10-06. Estimated completion is 2026-04-15.
What conditions does trial NCT05789173 study?
This clinical trial studies the following conditions: Drug-Drug Interaction. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT05789173?
The interventions under investigation include: Methadone and Tizanidine (DRUG), Efavirenz, Methadone and Tizanidine (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT05789173?
This trial is sponsored by Indiana University, which has 1,026 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT05789173 being conducted?
This trial has 1 study location across Indiana. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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