Minocycline as Adjunctive Treatment for Treatment Resistant Depression

NCT03947827 · Status: COMPLETED · Phase: PHASE3 · Type: INTERVENTIONAL · Enrollment: 76

Last updated 2026-03-27

No results posted yet for this study

Summary

Major depressive disorder (MDD) is a leading cause of disability worldwide. Up to 50% of patients experience treatment resistant depression (TRD), which accounts for a vast majority of disease burden. Current medications for TRD have limited efficacy and can be associated with intolerable side effects. Therefore, there is a need for finding new treatment targets. Accumulating evidence suggests some patients with MDD including those with TRD, display brain inflammation. Thus, patients with TRD may benefit from medications that can reduce this inflammation. Minocycline is an antibiotic which can cross the blood-brain barrier and has effects on several systems implicated in depression. The principal investigator led the first pilot study of minocycline as an add-on treatment in TRD demonstrating that it led to a significant reduction in depressive symptoms compared to placebo and these findings require replication in a larger sample to confirm the efficacy and tolerability of this treatment approach.

This study is a 12 week, double-blind, placebo-controlled trial of minocycline as add-on treatment for patients suffering from a major depressive episode who have failed to respond to antidepressant treatment, confirmed by the Structured Clinical Interview for DSM-5 (SCID-5) and the Antidepressant Treatment History Form (ATHF) at screening. After screening and randomization to the two parallel arms of the trial, 50 patients will receive minocycline added to treatment as usual (TAU) and 50 patients will receive placebo added to TAU. Clinical assessment will include the Hamilton Depression Rating Scale (HRSD-17), Clinical Global Impression scale (CGI), World Health Organization Quality of Life Short Form (WHOQOL-BREF), and Generalized Anxiety Disorder scale (GAD-7), administered at each study visit (baseline, week 2, 6, and 12). Side effects checklists will be undertaken at each visit. Minocycline will be started at 100 mg once daily and will be increased to 100 mg twice daily at two weeks. Secondary outcomes include inflammatory biomarkers measured at baseline, weeks 6 and 12.

This trial will provide further evidence of minocycline's efficacy and acceptability as a treatment option for patients with TRD and provide insights into its mechanism of action.

Conditions

Interventions

DRUG

Minocycline

Participants will be randomized to receive either Minocycline or placebo added to standard oral antidepressants.

Sponsors & Collaborators

  • The Physicians' Services Incorporated Foundation

    collaborator OTHER
  • Centre for Addiction and Mental Health

    lead OTHER

Principal Investigators

  • Ishrat Husain, MBBS, MD(Res.) · CAMH

Study Design

Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Model
PARALLEL

Eligibility

Min Age
18 Years
Max Age
80 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2020-02-01
Primary Completion
2025-01-07
Completion
2025-01-07

Countries

  • Canada

Study Locations

More Related Trials

Entities

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT03947827 on ClinicalTrials.gov