Faculty Bibliography

This study aimed to assess the effect of a single infusion of intravenous (IV) ketamine on suicidal ideation in patients with treatment-resistant depression (TRD). Patients with TRD were randomized in a double-blind fashion to a single infusion of IV ketamine or IV midazolam placebo. Suicidal ideation was measured using the Montgomery-Asberg Depression Rating Scale (MADRS) suicide item at 3, 5, 7, 14 and 30 days post infusion. Clinically significant suicidal ideation was defined as a MADRS suicide item score ≥2. Forty patients who received IV ketamine and 16 who received IV midazolam had suicide item scores of ≥2 at baseline (IV ketamine group mean 2.90±0.74; IV midazolam group 2.69±0.70). The mean suicide scores of these groups differed significantly from each other on day 30; the IV ketamine group had a lower mean score than controls (2.03±1.59 vs. 3.00±1.41, t-test p = 0.049; Hedges' g 0.71). Among patients with a suicide score of ≥2 at baseline and <2 at day 3, the two groups did not differ significantly on mean scores changes at days 3, 5, 7, 14 or 30. Recurrence of suicidal ideation was extensive in both treatment groups. A single infusion of IV ketamine may reduce suicidal ideation in TRD out to 30 days post infusion, but early anti-suicidal effects appear to diminish rapidly. This post-hoc analysis was not powered to compare different doses of ketamine. A single infusion of IV ketamine might have a role as an adjunct to standard treatments in patients with TRD and suicidal ideation. Trial registration: NCT01920555.

(Appeared originally in Frontiers in Psychiatry 2020 Dec 23; 11:595584).

Background: AXS-05 (dextromethorphan-bupropion modulated delivery tablet) is an investigational, oral, NMDA receptor antagonist with multimodal activity being developed for MDD.
Method(s): AXS-05 was evaluated in two double-blind, randomized, controlled, 6-week trials. The GEMINI trial was placebo-controlled and the ASCEND trial used bupropion as the control. The primary efficacy variable in both was change in the MADRS total score. Here we examine the efficacy in the first 2 weeks of treatment.
Result(s): AXS-05 met the primary endpoint in both studies. In GEMINI (N=327), starting at Week-1, AXS 05 was superior to placebo on: mean MADRS improvement (7.3 vs. 4.9; p=0.007), MADRS response (>=50% improvement; 15% vs. 7%; p=0.035), CGI-I (22% vs. 13%; p=0.035), CGI-S (0.7 vs. 0.4; p=0.013) and Q-LES-Q-SF (9.0% vs. 5.8%; p=0.031). At Week-2, AXS-05 was superior to placebo on MADRS remission (<=10; 17% vs. 8%; p=0.013) and SDS (6.8 vs. 4.5; p=0.003). In ASCEND (N=80), starting at Week-1, AXS-05 was superior to bupropion on: CGI-I (18% vs. 3%; p=0.045) and MADRS-6 response (>=50% improvement; 16% vs. 3%; p=0.044). From Week-2, AXS-05 was superior to bupropion on: mean MADRS improvement (12.5 vs. 7.8; p=0.024), MADRS remission (<=10; 26% vs. 3%; p=0.004), and CGI-S (1.41 vs. 0.9; p=0.049).
Conclusion(s): AXS-05 demonstrated rapid and statistically significant improvements in depression at Weeks 1 and 2 in placebo- and active- controlled trials. In both studies, rapid remission from depressive symptoms was achieved by Week-2 and maintained over the 6-week treatment period. The novel mechanisms of action of AXS-05 may contribute to these rapid antidepressant effects. Supported By: Axsome Therapeutics Keywords: Rapid Anti-Depressant Effect, Major Depressive Disorder (MDD), NMDA Antagonists, Novel Treatments, Glutamate Neurotransmission
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OBJECTIVE/UNASSIGNED:Preclinical studies point to the KCNQ2/3 potassium channel as a novel target for the treatment of depression and anhedonia, a reduced ability to experience pleasure. The authors conducted the first randomized placebo-controlled trial testing the effect of the KCNQ2/3 positive modulator ezogabine on reward circuit activity and clinical outcomes in patients with depression. METHODS/UNASSIGNED:Depressed individuals (N=45) with elevated levels of anhedonia were assigned to a 5-week treatment period with ezogabine (900 mg/day; N=21) or placebo (N=24). Participants underwent functional MRI during a reward flanker task at baseline and following treatment. Clinical measures of depression and anhedonia were collected at weekly visits. The primary endpoint was the change from baseline to week 5 in ventral striatum activation during reward anticipation. Secondary endpoints included depression and anhedonia severity as measured using the Montgomery-Ã…sberg Depression Rating Scale (MADRS) and the Snaith-Hamilton Pleasure Scale (SHAPS), respectively. RESULTS/UNASSIGNED:The study did not meet its primary neuroimaging endpoint. Participants in the ezogabine group showed a numerical increase in ventral striatum response to reward anticipation following treatment compared with participants in the placebo group from baseline to week 5. Compared with placebo, ezogabine was associated with a significantly larger improvement in MADRS and SHAPS scores and other clinical endpoints. Ezogabine was well tolerated, and no serious adverse events occurred. CONCLUSIONS/UNASSIGNED:The study did not meet its primary neuroimaging endpoint, although the effect of treatment was significant on several secondary clinical endpoints. In aggregate, the findings may suggest that future studies of the KCNQ2/3 channel as a novel treatment target for depression and anhedonia are warranted.

Replicated international studies have underscored the human and societal costs associated with major depressive disorder. Despite the proven efficacy of monoamine-based antidepressants in major depression, the majority of treated individuals fail to achieve full syndromal and functional recovery with the index and subsequent pharmacological treatments. Ketamine and esketamine represent pharmacologically novel treatment avenues for adults with treatment-resistant depression. In addition to providing hope to affected persons, these agents represent the first non-monoaminergic agents with proven rapid-onset efficacy in major depressive disorder. Nevertheless, concerns remain about the safety and tolerability of ketamine and esketamine in mood disorders. Moreover, there is uncertainty about the appropriate position of these agents in treatment algorithms, their comparative effectiveness, and the appropriate setting, infrastructure, and personnel required for their competent and safe implementation. In this article, an international group of mood disorder experts provides a synthesis of the literature with respect to the efficacy, safety, and tolerability of ketamine and esketamine in adults with treatment-resistant depression. The authors also provide guidance for the implementation of these agents in clinical practice, with particular attention to practice parameters at point of care. Areas of consensus and future research vistas are discussed.

BACKGROUND:Depression affects many children and adolescents, leading to poor academic performance, impaired psychosocial functioning, and an increased frequency of suicidal behavior. Depression has also been notably associated with trauma and distress tolerance. Our study sought to understand the relationships of these variables across age and sex categories in youth and adolescents. METHODS:The current study examined data from a total of 324 participants between the ages of 7 and 17 years-old who were a part of a larger study. Data related to age, sex, depression, trauma, and distress tolerance were examined. RESULTS:A multiple regression revealed a significant interaction between age and sex on depression severity. Further, trauma and age by sex categories significantly predicted depression score, as well as distress tolerance predicting depression score. Lastly, a regression analysis, including trauma, distress tolerance, and age by sex categories were significant predictors of depression. LIMITATIONS/CONCLUSIONS:The results are limited by the cross-sectional design. CONCLUSION/CONCLUSIONS:Clinicians should consider age by sex effects when treating childhood depression. Future research should further the understanding of depression across age and sex groups, as well as among children with extensive trauma experiences. Future research should also seek to further understand the implications of distress tolerance therapy on childhood depression.

Lasting effects of adversity, such as exposure to childhood adversity (CA) on disease risk, may be embedded via epigenetic mechanisms but findings from human studies investigating the main effects of such exposure on epigenetic measures, including DNA methylation (DNAm), are inconsistent. Studies in perinatal tissues indicate that variability of DNAm at birth is best explained by the joint effects of genotype and prenatal environment. Here, we extend these analyses to postnatal stressors. We investigated the contribution of CA, cis genotype (G), and their additive (G + CA) and interactive (G × CA) effects to DNAm variability in blood or saliva from five independent cohorts with a total sample size of 1074 ranging in age from childhood to late adulthood. Of these, 541 were exposed to CA, which was assessed retrospectively using self-reports or verified through social services and registries. For the majority of sites (over 50%) in the adult cohorts, variability in DNAm was best explained by G + CA or G × CA but almost never by CA alone. Across ages and tissues, 1672 DNAm sites showed consistency of the best model in all five cohorts, with G × CA interactions explaining most variance. The consistent G × CA sites mapped to genes enriched in brain-specific transcripts and Gene Ontology terms related to development and synaptic function. Interaction of CA with genotypes showed the strongest contribution to DNAm variability, with stable effects across cohorts in functionally relevant genes. This underscores the importance of including genotype in studies investigating the impact of environmental factors on epigenetic marks.

BACKGROUND:Adjunctive antidepressants are frequently used for bipolar depression but their clinical efficacy has been studied in few trials and little is known about how co-occurring manic symptoms affect treatment response. METHODS:Bipolar Clinical Health Outcomes Initiative in Comparative Effectiveness (N = 482) and Lithium Treatment Moderate-Dose Use Study (N = 281) were similar comparative effectiveness trials on outpatients with bipolar disorder comparing four different randomized treatment arms with adjunctive personalized guideline-based treatment for 24 weeks. Adjunctive antidepressant treatment could be used if clinically indicated and was assessed at every study visit. Adjusted mixed effects linear regression analyses compared users of antidepressants to nonusers overall and in different subcohorts. RESULTS:Of the 763 patients, 282 (37.0%) used antidepressant drugs during the study. Antidepressant users had less improvement compared to nonusers on the Clinical Global Impression Scale for Bipolar Disorder and on measures of depression. This was particularly true among patients with co-occurring manic symptoms. Exclusion of individuals begun on antidepressants late in the study (potentially due to overall worse response) resulted in no differences between users and nonusers. We found no differences in treatment effects on mania scales. CONCLUSIONS:In this large cohort of outpatients with bipolar disorder, clinically indicated and guideline-based adjunctive antidepressant treatment was not associated with lower depressive symptoms or higher mania symptoms. The treatment-by-indication confounding due to the nonrandomized design of the trials complicates causal interpretations, but no analyses indicated better treatment effects of adjunctive antidepressants.

Background: Transcranial photobiomodulation (t-PBM) with nearinfrared (NIR) light penetrates into the cerebral cortex and is absorbed by the mitochondrial enzyme cytochrome c oxidase (CCO), stimulating the mitochondrial respiratory chain. t-PBM also significantly increases cerebral blood flow (CBF) and oxygenation. Small studies have reported that t-PBM may be an effective treatment in major depressive disorder (MDD). However, relationships between t-PBM dose (irradiance and/or total energy) and clinical or biological effects are unclear. In this experimental medicine study, we evaluated the dose-dependent effects of t-PBM in MDD subjects.
Method(s): We enrolled subjects meeting DSM-5 criteria for MDD, not treatment-resistant (0-2 failed antidepressants in the current episode), either unmedicated or on stable doses of antidepressants, with no other significant medical or psychiatric comorbidities. All subjects underwent 4 t-PBM sessions in the MRI scanner, 1 week apart, administered in random order, with 1) sham (no energy emitted); 2) High dose: Pulse wave (PW), average irradiance 300mW/cm2, peak irradiance 900 mW/cm2, 42Hz, 33% duty cycle, 4.3 KJ total energy; 3) Medium dose: Continuous Wave (CW), 300 mW/cm2 irradiance, 2.4 KJ total energy; 4) Low dose: CW, 50mW/cm2 irradiance; 1.4 kJ total energy. Other t-PBM parameters were kept unchanged (808 nm; 12.0 cm2 x 2 treatment area; delivered to the anterior prefrontal cortex, bilaterally). Resting state multi-echo (3), multi-band (2) fMRI was recorded on a 3T Siemens Trio using a 12ch head coil (TR = 2500ms, TE1 = 12.8ms, TE2 = 32.33 ms, TE3 = 51.86 ms, 60 slices, slice thickness 2.5mm) before, during and after t-PBM, using measures of the change in blood-oxygenation-level dependent (BOLD) signal on fMRI as marker of target engagement (t-PBM effect on cerebral blood flow). The BOLD signal was preprocessed using standardized automated tools [AFNI]. In order to test whether t-PBM modulated the BOLD signal during and after tPBM, we performed a region-of-interest (ROI) analysis taking into account the illuminated region of the brain. We extracted the signal from the transverse frontopolar giry, bilateral (ROIs 6 and 81 from the Desikan atlas) and separated the resulting time series into the pre-, peri-, and post-stimulation segments. We then performed spectral analysis in order to measure the BOLD power during each segment, employing the Thomson multitaper technique to increase the signal-to-noise ratio of the ensuing power estimates. This produced three spectra for each echo and dose (before, during, and after stimulation). We then tested for significant differences in BOLD power spectrum both during and after stimulation in each t-PBM dose, compared to sham (Wilcoxon rank sum test, corrected for multiple comparisons by controlling the false discovery rate at 0.05).
Result(s): We analyzed data from the first 7 MDD subjects (age = 32.1 +/- 13.1; 57% female) undergoing all 4 experimental sessions. We found a dose-dependent effect of t-PBM on the BOLD. Namely, low-intensity t-PBM produced a marked decrease in BOLD that was observed in all three echos (p < 0.05, n = 7). The reduction in BOLD was most pronounced near 0.03 Hz at echos 2 and 3. In contrast, CW 300 mW/cm2 t-PBM increased BOLD power, with a significant increase resolved near 0.1 Hz at all 3 echos (p < 0.05, n = 7). This suggests that higher irradiance CW t-PBM increased the power of the "fast" component of the BOLD signal during stimulation. However, no significant differences from sham were observed during PW 300 mW/cm2 stimulation. We were also not able to detect any significant BOLD changes after tPBM (at any echo or t-PBM dose).
Conclusion(s): We found a U-shaped, dose-dependent effect of t-PBM on the BOLD, with the medium dose leading to an increase in the hemodynamic effect. These findings suggest that specific parameters of t-PBM (total energy, irradiance, CW versus PW) modulate the effect of near-infrared light on cerebral blood flow. This is important, as t-PBM doses optimized for their hemodynamic effect might also offer superior clinical efficacy