Introduction to the theme "Precision medicine and prediction in pharmacology"

T cells: an emerging cast of roles in bipolar disorder

Bipolar disorder (BD) is a distinctly heterogeneous and multifactorial disorder with a high individual and social burden. Immune pathway dysregulation is an important pathophysiological feature of BD. Recent studies have suggested a potential role for T lymphocytes in the pathogenesis of BD. Therefore, greater insight into T lymphocytes' functioning in patients with BD is essential. In this narrative review, we describe the presence of an imbalance in the ratio and altered function of T lymphocyte subsets in BD patients, mainly in T helper (Th) 1, Th2, Th17 cells and regulatory T cells, and alterations in hormones, intracellular signaling, and microbiomes may be potential causes. Abnormal T cell presence explains the elevated rates of comorbid inflammatory illnesses in the BD population. We also update the findings on T cell-targeting drugs as potentially immunomodulatory therapeutic agents for BD disease in addition to classical mood stabilizers (lithium, valproic acid). In conclusion, an imbalance in T lymphocyte subpopulation ratios and altered function may be involved in the development of BD, and maintaining T cell immune homeostasis may provide an overall therapeutic benefit.

Could "triple-therapy" considered as a novel-optimal treatment model for acute bipolar depression? A prospective real-world research in China

BACKGROUND

Results of researches of bipolar depression treatment are inconsistent and to our knowledge, no study has previously revealed an optimal treatment model for bipolar depression in the real-world through a prospective way.

OBJECTIVE

To find out an optimal treatment model for bipolar depression in the real-world by evaluating the effect of different treatment models: monotherapy, double-therapy and triple-therapy.

DESIGN

and Intervention: This 12 or 16-week, multi-center, real-world clinical study was conducted at 15 study sites (inpatient or outpatient department) in West China and a total of 573 patients completed the follow-up. During the study weeks, all researchers could choose a most proper treatment model freely basing on the evaluation of patient's symptoms and complete the follow-up according to the procedure.

MAIN OUTCOMES AND MEASURES

The primary outcomes were baseline-to-endpoint change in Montgomery-Asberg Depression Rating Scale (MADRS) total score and the constituent ratio of effects. Total score change in Young Mania Rating Scale (YMRS) and Clinical Global Impression (CGI) from baseline to endpoint, treatment-emergent mania rate and severe adverse events rate were used as secondary outcomes.

RESULTS

During all study weeks, all the 3 groups showed a statistically significant improvement in MARDS, YMRS and CGI (P＜0.001), but the triple-therapy group showed much more effective in significant response and response rates at endpoint than double-therapy group and monotherapy group (P＜0.001) with lower treatment-emergent mania rates (P = 0.001). At week 4, mean scores of MARDS in triple-therapy group are statistically significant lower than monotherapy group (P = 0.013) and at the endpoint, mean scores of MARDS in triple-therapy group are statistically significant lower than both double-therapy and monotherapy groups (P = 0.011). The severe adverse events rates are rare in all the 3 groups at week 4 and endpoint, and the rate of dry mouth in triple-therapy group at week 4 is statistically significant lower than the other 2 groups (P = 0.002).

CONCLUSIONS

Triple-therapy is more effective in treating bipolar depression than double-therapy and monotherapy model with a lower risk of developing manic symptoms.

TRIAL REGISTRATION

Chinese Clinical Trial Registry. Identifier: ChiCTR1800019064.

Efficacy of Adjunctive Infliximab vs Placebo in the Treatment of Adults With Bipolar I/II Depression: A Randomized Clinical Trial

IMPORTANCE

To our knowledge, no study has previously evaluated whether individuals with bipolar depression enriched a priori on the basis of biochemical and/or phenotypic immuno-inflammatory activation would differentially respond to an anti-inflammatory agent for the treatment of depressive symptoms.

OBJECTIVE

To assess the antidepressant efficacy of adjunctive infliximab, a monoclonal antibody targeting tumor necrosis factor, in adults with bipolar I and bipolar II depression and inflammatory conditions.

DESIGN, SETTING, AND PARTICIPANTS

This 12-week, randomized, double-blind, placebo-controlled, parallel-group trial of 60 participants was conducted at 2 outpatient tertiary care sites in Canada and the United States. Eligible adults (aged 18-65 years) met DSM-5-defined criteria for bipolar I or bipolar II depression and exhibited pretreatment biochemical and/or phenotypic evidence of inflammatory activation. Participants were enrolled between October 1, 2015, and April 30, 2018. Data analysis was performed from May 1 through July 31, 2018, using modified intent-to-treat analysis.

INTERVENTIONS

Patients were randomized to receive 3 intravenous infusions of infliximab therapy or placebo at baseline and at weeks 2 and 6 of the 12-week study.

MAIN OUTCOMES AND MEASURES

The primary efficacy outcome was baseline-to-end point (ie, week-12) change in Montgomery-Asberg Depression Rating Scale (MADRS) total score. History of childhood maltreatment, as assessed by the Childhood Trauma Questionnaire, was used for exploratory analyses as 1 of several secondary outcomes.

RESULTS

A total of 60 participants were randomized to infliximab (n = 29 [48%]; mean [SD] age, 45.0 [11.7] years; 20 of 28 female [71%]) or to placebo (n = 31 [52%]; mean [SD] age, 46.8 [10.2] years; 26 of 30 female [87%]) across study sites. Overall baseline-to-end point change in MADRS total score was observed across treatment × time interaction (χ2 = 10.33; P = .04); reduction in symptom severity was not significant at week 12 (relative risk, 1.09; 95% CI, 0.80-1.50; df = 1; P = .60). As part of a secondary analysis, a significant treatment × time × childhood maltreatment interaction was observed in which infliximab-treated individuals with childhood history of physical abuse exhibited greater reductions in MADRS total score (χ2 = 12.20; P = .02) and higher response rates (≥50% reduction in MADRS total score) (χ2 = 4.05; P = .04).

CONCLUSIONS AND RELEVANCE

Infliximab did not significantly reduce depressive symptoms compared with placebo in adults with bipolar depression. Results from secondary analyses identified a subpopulation (ie, those reporting physical and/or sexual abuse) that exhibited a significant reduction in depressive symptoms with infliximab treatment compared with placebo.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02363738.

Introduction to the Theme “New Therapeutic Targets”

“New Therapeutic Targets” is the theme of articles in the Annual Review of Pharmacology and Toxicology, Volume 59. Reviews in this volume discuss targets for a variety of conditions in need of new therapies, including type 2 diabetes, heart failure with preserved ejection fraction, obesity, thyroid-associated ophthalmopathy, tinnitus, multiple sclerosis, Parkinson's disease and other neurodegenerative diseases, pain, depression, post-traumatic stress disorder, muscle wasting diseases, cancer, and anemia associated with chronic renal disease. Numerous articles in this volume focus on the identification, validation, and utility of novel therapeutic targets, in particular, ones that involve new or unexpected molecular entities. This theme complements several previous themes, including “New Approaches for Studying Drug and Toxicant Action: Applications to Drug Discovery and Development,” “Precision Medicine and Prediction in Pharmacology,” and “New Methods and Novel Therapeutic Approaches in Pharmacology and Toxicology.”

Emotion processing in female youth: Testing the stability of the late positive potential

The Emotional Interrupt Task (EIT) has been used to probe emotion processing in healthy and clinical samples; however, research exploring the stability and reliability of behavioral measures and ERPs elicited from this task is limited. Establishing the psychometric properties of the EIT is critical, particularly as phenotypes and biological indicators may represent traitlike characteristics that underlie psychiatric illness. To address this gap, test-retest stability and internal consistency of behavioral indices and ERPs resulting from the EIT in healthy, female youth (n = 28) were examined. At baseline, participants were administered the EIT while high-density 128-channel EEG data were recorded to probe the late positive potential (LPP). One month later, participants were readministered the EIT. Four principal findings emerged. First, there is evidence of an interference effect at baseline, as participants showed a slower reaction time for unpleasant and pleasant images relative to neutral images, and test-retest of behavioral measures was relatively stable over time. Second, participants showed a potentiated LPP to unpleasant and pleasant images compared to neutral images, and these effects were stable over time. Moreover, in a test of the difference waves (unpleasant-neutral vs. pleasant-neutral), there was sustained positivity for unpleasant images. Third, behavioral measures and LPP demonstrated excellent internal consistency (odd/even correlations) across conditions. Fourth, highlighting important age-related differences in LPP activity, younger age was associated with larger LPP amplitudes across conditions. Overall, these findings suggest that the LPP following emotional images is a stable and reliable marker of emotion processing in healthy youth.

Antiviral Therapy

Antiviral therapy is one of the most exciting aspects of virology, since it has successfully employed basic science to generate very effective treatments for serious viral infections. Table 1 lists selected examples of those human viral diseases for which there are established antiviral drugs. Therapy for human immunodeficiency virus (HIV) infection has demonstrated that the potential impact antivirals can have on a lethal, chronic infection with lifesaving therapy administered to more than 12 million individuals by 2015. This dramatic advance is about to be recapitulated for the treatment of hepatitis C virus (HCV) infection. The development of new antiviral drugs is very much a work in progress, with active drug discovery programs for filoviruses, coronaviruses, dengue, and others.

Existing and Future Drugs for the Treatment of the Dark Side of Addiction

The identification of a heuristic framework for the stages of the addiction cycle that are linked to neurocircuitry changes in pathophysiology includes the binge/intoxication stage, the withdrawal/negative affect stage, and the preoccupation/anticipation (craving) stage, which represent neuroadaptations in three neurocircuits (basal ganglia, extended amygdala, and frontal cortex, respectively). The identification of excellent and validated animal models, the development of human laboratory models, and an enormous surge in our understanding of neurocircuitry and neuropharmacological mechanisms have provided a revisionist view of addiction that emphasizes the loss of brain reward function and gain of stress function that drive negative reinforcement (the dark side of addiction) as a key to compulsive drug seeking. Reversing the dark side of addiction not only explains much of the existing successful pharmacotherapies for addiction but also points to vast new opportunities for future medications to alleviate this major source of human suffering.