The Journal of Clinical Psychiatry
July 16, 2021
Ibrahim Turkoz, Ella Daly, Jaskaran Singh et al.
21 citations
For patients with treatment-resistant depression who did not show a response within the first week of treatment, a full four-week induction course of esketamine nasal spray plus an oral antidepressant may still provide benefit. In a pooled analysis of two phase 3 trials, among those not meeting early response criteria at day 2 or days 2 and 8, the odds of a response by day 28 were about 1.6 times higher with esketamine plus antidepressant compared to antidepressant plus placebo. The findings suggest that lack of early improvement does not preclude later benefit from the full induction course.
Psychiatry Research
March 15, 2023
Ibrahim Turkoz, J. Craig Nelson, Samuel T. Wilkinson et al.
19 citations
A post hoc analysis of two pooled 4-week phase 3 trials examined predictors of response and remission in patients with treatment-resistant depression receiving esketamine nasal spray plus a new oral antidepressant compared to a new oral antidepressant plus placebo nasal spray. Younger age, being employed, having fewer failed antidepressants in the current episode, and early reduction in Clinical Global Impression-Severity score at day 8 predicted better outcomes. Those on esketamine had 68% higher odds of response and 55% higher odds of remission. In the esketamine group, response was more likely in employed patients, those without baseline anxiety, and those with early symptom improvement.
The International Journal of Neuropsychopharmacology
December 14, 2022
David Williamson, Ibrahim Turkoz, Ewa Wajs et al.
11 citations
Dissociation encompasses distinct phenomena, some linked to esketamine treatment and potentially overlapping with psychosis symptoms. In a post hoc analysis of data from an open-label, phase 3 study of esketamine plus a newly initiated oral antidepressant in patients with treatment-resistant depression, dissociation was reported as an adverse event in 14.3% (109/764) of patients. CADSS scores generally aligned with investigator-reported dissociation severity, but no cutoff point reliably distinguished presence from absence of dissociation events. Hallucinations occurred in 5 patients, and no delusions were reported, indicating psychotic symptoms were uncommon.
Expert Review of Neurotherapeutics
June 1, 2025
Rosalie Girard Pepin, Fatemeh Seyfzadeh, David Williamson et al.
7 citations
Pharmacological treatment options for disorders of consciousness (DoC), which range from coma to minimally conscious state, remain limited due to the heterogeneity of causes such as traumatic brain injury, stroke, and infections. A lack of rigorous clinical trials has led to off-label use of drugs—including dopaminergic and GABAergic agents, antidepressants, statins, and anticonvulsants—often without clear mechanistic understanding. Robust longitudinal trials are needed, prioritizing early subacute intervention and better-defined outcomes that consider immediate responses and long-term quality of life. A shift toward personalized medicine and unified functional frameworks is advocated, along with increased use of AI tools to predict treatment responses.
Journal of Affective Disorders
November 1, 2024
J Douglas Bremner, David Williamson, Viola Vaccarino
5 citations
Dissociative symptoms can arise from psychological trauma or as a side effect of certain medications, making accurate assessment important. The 23-item Clinician Administered Dissociative States Scale (CADSS) was evaluated in 276 participants: 148 with trauma history and PTSD, 100 with trauma history but no PTSD, and 28 healthy controls without trauma or psychiatric disorder. The scale showed high internal consistency (Cronbach's alpha 0.91) and a single-factor structure. Trauma-exposed participants with PTSD had higher CADSS scores than those without PTSD or without trauma. Veterans with combat-related PTSD showed increased scores after exposure to combat-related stimuli. The CADSS performs reliably for assessing dissociation in psychologically traumatized individuals.
Journal of Affective Disorders
June 12, 2025
David Williamson, Linda Williamson, Viola Vaccarino et al.
2 citations
Dissociative symptoms are common in many patients with PTSD and also appear during the first esketamine treatment for treatment-resistant depression. Comparing 134 PTSD patients and 759 TRD patients receiving their first esketamine dose, dissociative symptoms were more prevalent overall in the esketamine group. However, the pattern differed: PTSD patients more often reported dissociative amnesia and identity fragmentation, while esketamine patients most frequently experienced depersonalization and derealization. This distinct pattern suggests that the underlying causes of dissociative symptoms may differ between these conditions.