1. World Health Organization. Depression fact sheet. Available from: https://www.who.int/news-room/fact-sheets/detail/depression. Accessed December 16, 2021.
2. Treatment resistant depression: what are the options?
3. European Medicines Agency. Clinical investigation of medicinal products in the treatment of depression. Available from: https://www.ema.europa.eu/en/clinical-investigation-medicinal-products-treatment-depression. Accessed December 16, 2021.
4. The economic cost of treatment-resistant depression in patients referred to a specialist service
5. Spravato® (esketamine hydrochloride). Summary of product characteristics. High Wycombe, UK: Janssen-Cilag Ltd; 2021.