Auckland, New Zealand – Researchers in New Zealand are exploring the potential benefits of using slow-release oral doses of ketamine as a therapy for treatment-resistant depression following a failed attempt at using MDMA therapy for post-traumatic stress disorder. The mid-stage clinical trial conducted by Douglas Pharmaceuticals showed promising results in terms of safety and efficacy of ketamine compared to a placebo.
The trial, which included 231 participants, aimed to address the limited pool of patients who may benefit from the treatment. Researchers used an “enrichment” design to select participants who initially responded to ketamine, leading to 59.5% of enriched participants dropping out of the trial due to lack of efficacy. Despite this challenge, the trial saw 57% of participants achieving remission at the initial enrichment phase.
During the randomized, double-blind, placebo-controlled phase, participants who responded to ketamine were divided into groups receiving different dosage levels. The results showed a dosage response, with the 180-mg group demonstrating statistically significant improvements in depressive symptoms compared to the placebo group at the end of the trial. However, challenges arose as 59.5% of participants dropped out by day 92, with most attributing their decision to a lack of efficacy.
Researchers emphasized the need for future unenriched clinical trials to address population levels of treatment response accurately. Despite the dropouts, the trial indicated that oral doses of ketamine were generally safe, with no significant cardiovascular side effects observed. Common side effects included mild to moderate headache, dizziness, and anxiety, but potential abuse or diversion concerns were not extensively monitored during the trial.
While the results of the trial showed promise in treating treatment-resistant depression with ketamine, researchers acknowledged the limitations of their study design. Moving forward, further research is needed to explore the full potential of ketamine as a therapeutic option for individuals struggling with depression.