Real-world clinical data on the long-term effectiveness and safety of generic racemic ketamine treatment.

Ketamine is a highly effective treatment for difficult-to-treat or treatment-resistant depression (TRD). The commercially developed intranasal spray containing S-ketamine has demonstrated short and long-term efficacy and safety in phase 3 clinical trials leading to regulatory approval for TRD in many countries. Conversely, generic racemic ketamine is prescribed 'off-label'. There is minimal data on the effectiveness and safety of generic racemic ketamine treatment of >4 weeks duration. The aim of this study was to report the effectiveness and safety of ongoing racemic ketamine treatment for TRD for up to six months in real-world clinical settings. Safety was assessed using a structured monitoring framework (Ketamine Side Effect Tool). Retrospective, deidentified data were collected and analysed from 65 patients with TRD (46.1 ± 14.9 years old; 52.3 % female) who received racemic ketamine treatments over a period of 8 weeks to 6 months. Effectiveness and safety data were summarised using descriptive statistics and frequency distributions. Data suggested effectiveness, with response rates of 35 % at 8 weeks (16/45) and 44.2 % at 6 months (19/43). Suicidality scores improved in 73.3 % of patients at their last available assessment. Similarly, the results indicated that racemic ketamine was well tolerated. Our findings suggest structured safety monitoring facilitated early identification of emerging adverse effects in a few patients, allowing prompt clinical management, with no adverse sequelae. These findings support the effectiveness and safety of long-term racemic ketamine treatment for patients with TRD and highlight the importance of using a structured safety monitoring framework in clinical care.