Effects of Switching From Racemic Methadone to R-methadone on QTc Intervals (MePhaCard)

University of Oslo (UIO)

Status and phase: Active, not recruiting; Phase 4

Conditions: Heart Arrhythmia; Adverse Drug Effect; Drug Effect

Treatments: Drug: Same individuals treated with racemic methadone and switched to levomethadone (R-methadone)

Study type: Interventional

Funder types: Other

Identifiers

NCT04254731

2012/793 REK

Details and patient eligibility

About

Effects of switching from racemic methadone to R-methadone on serum methadone concentrations and QTc intervals

Full description

Racemic methadone may prolong the QTc interval, which is associated with fatal arrhythmias. In vitro studies have shown that R-methadone has less inhibitory effect than S-methadone on the voltage-gated potassium channel current, and is thus thought to have less effect on the QTc interval.

The investigators hypothesized that switching from racemic to R-methadone would reduce the methadone serum concentration and also its effect on the QTc interval.

Enrollment: 10 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Stabilized on daily methadone dose
• Not using other drugs of abuse
• QTc-time recorded automatically, patient inclusion if QTc interval was greater or equal to 450 ms
• Older than 18 years
• Can sign and understand a written Consent

Exclusion criteria

• Can not cooperate regarding observed daily drug intake
• Serious psychiatric disease
• Untreated serious somatic disease
• Pregnancy

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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10 participants in 1 patient group

Cross over study before and after drug switch

Other group

Description:

Stabilized on racemic methadone dose, switched to R-methadone of half racemic methadone dose. Cross over study, own control

Treatment:

Drug: Same individuals treated with racemic methadone and switched to levomethadone (R-methadone)