Psych Congress NetworkKetamine Treatment in TRD Should Last 4 Weeks or More for Antidepressant Benefit

Previous trials suggested that intravenous racemic ketamine was effective, but phase 3 trials were necessary to confirm the findings.

The use of subcutaneous racemic ketamine for treatment-resistant depression (TRD) has been thoroughly investigated in a study led by Dr. Colleen Loo. Conducted in Australia and New Zealand, the study explored the efficacy and safety of a 4-week course of this treatment method among TRD patients, comparing flexible-dose versus fixed-dose approaches and analyzing practical implications for the future.

Key Points:

• The study assessed the acute efficacy and safety of a 4-week course of subcutaneous racemic ketamine for TRD, with a double-blind, randomized, active-controlled trial design.
• Midazolam was chosen as the active control drug, and ketamine’s efficacy was found to be dose-related.
• Two cohorts were compared: fixed-dose (cohort 1) and flexible response-guided dosing (cohort 2), with the latter showing significant antidepressant efficacy.
• Cohort 1 did not yield significant results due to an insufficient dose.
• A prototype of the Ketamine Side Effect Tool (KSET) was used to monitor safety comprehensively, with no notable concerns identified.

Additional Points:

• The study emphasizes the importance of individualized, response-guided dosing and an adequate dose for efficacy.
• It also highlights the necessity for ongoing treatment beyond 4 weeks to maintain antidepressant effects.
• Long-term effects of ongoing ketamine treatment still require careful monitoring and data collection.

Conclusion:

• The study’s findings present subcutaneous ketamine as a practical and safe treatment option for TRD, especially when individualized dosing approaches are employed, and emphasize the need for ongoing treatment and careful monitoring.