Safety, Tolerability, PK Profile, and Symptom Response of a 7-Day Dosing With 25 mg or 50 mg Daily of REL-1017 in MDD

Depressive Disorder, Major Clinical Trial

Official title: Phase 2a Multicenter Randomized Double-Blind Placebo-Controlled Study to Assess the Safety, Tolerability, PK Profile, and Symptom Response of a 7-Day Dosing of REL-1017 as Adjunctive Therapy in the Treatment of Pts Diagnosed With MDD

Status Completed

Clinical Trial Summary

This a Phase 2a, multicenter, randomized, double-blind, placebo controlled 3 arm study to assess the safety and tolerability of multiple oral doses of REL-1017 25 mg and 50 mg as adjunctive therapy in the treatment of patients diagnosed with major depressive disorder (MDD). The patients will be adults with MDD who are diagnosed with a current MDE who have experienced an inadequate response to 1 to 3 courses of treatment with an antidepressant medication. This population will provide the opportunity to compare the safety and efficacy effects of treatment with an approved antidepressant in conjunction with REL-1017 versus the effects of an antidepressant alone. This study includes in-patient and out-patient periods.

Clinical Trial Description

Currently available medications have proven to be useful for the treatment of depression, but also have limitations including low response rates, a significant number of treatment resistant patients, and time-lag for response, which emphasizes a major unmet need for more efficacious and faster-acting antidepressants. Recent studies have demonstrated that ketamine, a non-competitive glutamate-N-methyl-D-Aspartate (NMDA) receptor antagonist, produces rapid onset (2 hours) and long-lasting (7 days) antidepressant actions in treatment resistant patients. This rapid action, by a mechanism completely different from typical monoamine reuptake inhibitors, represents a significant finding in the field of depression.

Racemic methadone, the 50/50 combination of d-methadone and l-methadone, has been in widespread use for decades and has been studied extensively. Methadone is currently approved for use in the management of severe pain, detoxification treatment of opioid addiction, and maintenance treatment of opioid addiction.

The results of a study evaluating the receptor binding profiles of racemic methadone and its stereoisomers suggest that d-methadone does not essentially contribute to the opioid effect of racemic methadone and that it has a 10 times lower affinity for the mu1, mu2, and delta opioid receptors compared to l-methadone. Racemic methadone and its d- and l isomers exhibit similar affinities for the non-competitive binding site of the NMDA receptor and are non-competitive NMDA receptor antagonists.

In the forced swim test, a rodent behavioral model of antidepressant activity, both ketamine and d-methadone at all doses tested significantly decreased the immobility of the rats compared to the vehicle suggesting antidepressant like activity. Neither drug increased spontaneous locomotor activity.

Relmada has conducted 2 clinical studies to identify the dose levels of REL-1017 (d-methadone) that have little to no opioid effects and that are expected to possess NMDA antagonistic properties for the evaluation of oral REL-1017 in the treatment of MDD and neuropathic pain conditions. Initial Phase 1 single ascending dose and multiple ascending dose clinical studies of REL-1017 were designed to evaluate the safety and tolerance of the pure d methadone isomer in healthy opioid-naïve subjects and identify a safe and potentially effective dose range in this population. These studies showed that REL-1017 was safe and well-tolerated at single oral doses up to 150 mg (maximum tolerated dose) and up to 75 mg administered once daily for 10 days in healthy opioid-naïve subjects.

The pre-clinical and previous clinical experience with REL-1017 (d-methadone) provided the basis for the initiation of the present study, which will extend the evaluation of the safety, tolerability, and PK of REL-1017 at 2 doses with repeated administration to depressed patients. Since REL-1017 is proposed for use as adjunctive therapy in the treatment of patients diagnosed with major depressive disorder (MDD), the patients will be male adults with MDD who are diagnosed with a current depressive episode who have experienced an inadequate response to 1 to 3 courses of treatment with an antidepressant medication.

Based on the safety data from Protocol REL-1017-111, single doses of 5 mg, 20 mg, 60 mg, 100 mg, and 150 mg of REL-1017 or placebo were well tolerated. The results of Protocol REL-1017-112 evaluated 10 days of dosing with 25 mg, 50 mg and 75 mg of REL-1017 or placebo, and no impact on safety was observed. In spite of the confirmed dose proportionality, the comparison of concentration and exposure between the 50 mg and 75 mg REL-1017 treatment groups demonstrated only slight differences. Consequently, 25 mg and 50 mg doses were chosen for administration in Protocol REL-1017-202 as single daily doses over a period of 7 days.

Thus, as a single isomer of racemic methadone, d-methadone has been shown to possess NMDA antagonist properties with virtually no opioid activity or ketamine-like toxicities at the expected therapeutic doses.

In this study, adult male patients with MDD who are diagnosed with a current MDE and who have experienced an inadequate response to 1 to 3 courses of treatment with an antidepressant medication will be randomized to study drug in a 1:1:1 ratio. Approximately 15 patients each will receive REL-1017 25 mg, REL-1017 50 mg, or placebo once daily for 7 days. Endpoints include assessments of safety, tolerability, efficacy and pharmacokinetics of REL-1017. Patients will be required to stay in the clinic for 10 days and will then be followed as an outpatient for 12 additional days. ;

Related Conditions & MeSH terms

• Depression
• Depressive Disorder
• Depressive Disorder, Major
• Depressive Disorder, Treatment-Resistant

• NCT number: NCT03051256
• Study type: Interventional
• Source: Relmada Therapeutics, Inc.
• Status: Completed
• Phase: Phase 2
• Start date: May 11, 2018
• Completion date: September 30, 2019