A 12-Week Double-Blind, Placebo-Controlled, Flexible-Dose Trial of Vilazodone in Generalized Social Anxiety Disorder

Pharmacotherapy for Anxiety Disorders: From First-Line Options to Treatment Resistance

In this review, the author examines the evidence for psychopharmacologic treatments among adults for generalized anxiety disorder, panic disorder, and social anxiety disorder derived from clinical trials. For each disorder, major categories of drugs are reviewed, and then the evidence-based medications in each category are discussed. The author reviews key safety and tolerability considerations for each of the medications or classes. Evidence-based dosing for most specific agents is displayed in a comprehensive reference table. Subsequently, the author synthesizes the available information to suggest a pragmatic stepwise approach to treatment that accounts for patient-specific factors. To inform the guidance, the author incorporates and refines perspectives from treatment guidelines already written by clinical professional organizations. The author also briefly reviews the relatively new quantitative systematic review methodology of network meta-analysis (NMA) and discusses how NMA may help guide pharmacologic treatment sequencing decisions in the future by way of ranking treatments according to effect size and the relative amount of study to which treatments have been subject. Caveats of NMA studies are briefly discussed, as are results of recent NMAs regarding the pharmacologic treatment of anxiety disorders.

Pharmacotherapy of Anxiety Disorders: Current and Emerging Treatment Options

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

The effects of inhibition of fatty acid amide hydrolase (FAAH) by JNJ-42165279 in social anxiety disorder: a double-blind, randomized, placebo-controlled proof-of-concept study

JNJ-42165279 is a selective inhibitor of fatty acid amide hydrolase (FAAH), the enzyme responsible for the degradation of fatty acid amides (FAA) including anandamide (AEA), palmitoylethanolamide (PEA), and N-oleoylethanolamide (OEA). We assessed the efficacy, safety, tolerability, pharmacokinetics, and pharmacodynamics of treatment with JNJ-42165279 in subjects with social anxiety disorder (SAD). This was a multicenter, double-blind, placebo-controlled study randomizing subjects to 12 weeks of treatment with either JNJ-42165279 (25 mg daily) or placebo (PBO). The primary endpoint was the change in the Liebowitz Social Anxiety Scale (LSAS) total score from baseline to end of study. Secondary endpoints included the Hamilton Anxiety Scale (HAM-A), Hamilton Depression Rating Scale (HDRS₁₇), and the Clinical Global Impression-Improvement (CGI-I). Samples were collected for plasma concentration of AEA, PEA, OEA, and JNJ-42165279. A total of 149 subjects were enrolled with a mean baseline LSAS total score of 102.6 (SD 16.84). The mean change from baseline (SD) in LSAS total score at week 12 was numerically greater for JNJ-42165279: -29.4 (27.47) compared to PBO: -22.4 (23.57) but not significant. The percentage of subjects with ≥30% improvement from baseline in the LSAS total score was significantly higher for JNJ-42165279 (42.4%) compared to PBO (23.6%) (p value = 0.04). The percentage of subjects with a CGI-I score of much or very much improved was also significantly higher for JNJ-42165279 (44.1%) than for PBO (23.6%) (p value = 0.02). The drug was well tolerated. JNJ-42165279 appears to elicit an anxiolytic effect in subjects with SAD although trough concentrations with 25 mg once daily appeared to be insufficient to completely inhibit FAAH activity which may have led to suboptimal efficacy. ClinicalTrials.gov Identifier: NCT02432703.

Current and Novel Psychopharmacological Drugs for Anxiety Disorders

Anxiety disorders, including panic disorder/agoraphobia (PDA), generalized anxiety disorder (GAD), social anxiety disorder (SAD), and others, are the most prevalent mental disorders. In this paper, recommendations are given for the psychopharmacological treatment of these disorders which are based on comprehensive treatment guidelines, meta-analyses, and systematic reviews of available randomized controlled studies. Anxiety disorders can effectively be treated with psychotherapy, pharmacotherapy, or a combination of both. First-line drugs are the selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). Benzodiazepines are not recommended for routine use due to their possible addiction potential. Other treatment options include the calcium modulator pregabalin, tricyclic antidepressants, buspirone, moclobemide, and others. Drug treatment can be combined with psychological treatments. Novel treatment strategies include medications that act on GABA, glutamate, and other neurotransmitter systems. After remission, medications should be continued for 6 to 12 months.

Pharmacotherapy of Anxiety Disorders: Current and Emerging Treatment Options

Anxiety disorders are the most prevalent psychiatric disorders and a leading cause of disability. While there continues to be expansive research in posttraumatic stress disorder (PTSD), depression and schizophrenia, there is a relative dearth of novel medications under investigation for anxiety disorders. This review's first aim is to summarize current pharmacological treatments (both approved and off-label) for panic disorder (PD), generalized anxiety disorder (GAD), social anxiety disorder (SAD), and specific phobias (SP), including selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), azapirones (e.g., buspirone), mixed antidepressants (e.g., mirtazapine), antipsychotics, antihistamines (e.g., hydroxyzine), alpha- and beta-adrenergic medications (e.g., propranolol, clonidine), and GABAergic medications (benzodiazepines, pregabalin, and gabapentin). Posttraumatic stress disorder and obsessive-compulsive disorder are excluded from this review. Second, we will review novel pharmacotherapeutic agents under investigation for the treatment of anxiety disorders in adults. The pathways and neurotransmitters reviewed include serotonergic agents, glutamate modulators, GABAergic medications, neuropeptides, neurosteroids, alpha- and beta-adrenergic agents, cannabinoids, and natural remedies. The outcome of the review reveals a lack of randomized double-blind placebo- controlled trials for anxiety disorders and few studies comparing novel treatments to existing anxiolytic agents. Although there are some recent randomized controlled trials for novel agents including neuropeptides, glutamatergic agents (such as ketamine and d-cycloserine), and cannabinoids (including cannabidiol) primarily in GAD or SAD, these trials have largely been negative, with only some promise for kava and PH94B (an inhaled neurosteroid). Overall, the progression of current and future psychopharmacology research in anxiety disorders suggests that there needs to be further expansion in research of these novel pathways and larger-scale studies of promising agents with positive results from smaller trials.

Pharmacotherapy for social anxiety disorder (SAnD)

BACKGROUND

Recognition is growing that social anxiety disorder (SAnD) is a chronic and disabling disorder, and data from early trials demonstrate that medication may be effective in its treatment. This systematic review is an update of an earlier review of pharmacotherapy of SAnD.

OBJECTIVES

To assess the effects of pharmacotherapy for social anxiety disorder in adults and identify which factors (methodological or clinical) predict response to treatment.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Controlled Trials Register (CCMDCTR-Studies and CCMDCTR-References) to 17 August 2015. The CCMDCTR contains reports of relevant RCTs from MEDLINE (1950-), Embase (1974-), PsycINFO (1967-) and CENTRAL (all years). We scanned the reference lists of articles for additional studies. We updated the search in August 2017 and placed additional studies in Awaiting Classification, these will be incorporated in the next version of the review, as appropriate.

SELECTION CRITERIA

We restricted studies to randomised controlled trials (RCTs) of pharmacotherapy versus placebo in the treatment of SAnD in adults.

DATA COLLECTION AND ANALYSIS

Two authors (TW and JI) assessed trials for eligibility and inclusion for this review update. We extracted descriptive, methodological and outcome information from each trial, contacting investigators for missing information where necessary. We calculated summary statistics for continuous and dichotomous variables (if provided) and undertook subgroup and sensitivity analyses.

MAIN RESULTS

We included 66 RCTs in the review (> 24 weeks; 11,597 participants; age range 18 to 70 years) and 63 in the meta-analysis. For the primary outcome of treatment response, we found very low-quality evidence of treatment response for selective serotonin reuptake inhibitors (SSRIs) compared with placebo (number of studies (k) = 24, risk ratio (RR) 1.65; 95% confidence interval (CI) 1.48 to 1.85, N = 4984). On this outcome there was also evidence of benefit for monoamine oxidase inhibitors (MAOIs) (k = 4, RR 2.36; 95% CI 1.48 to 3.75, N = 235), reversible inhibitors of monoamine oxidase A (RIMAs) (k = 8, RR 1.83; 95% CI 1.32 to 2.55, N = 1270), and the benzodiazepines (k = 2, RR 4.03; 95% CI 2.45 to 6.65, N = 132), although the evidence was low quality. We also found clinical response for the anticonvulsants with gamma-amino butyric acid (GABA) analogues (k = 3, RR 1.60; 95% CI 1.16 to 2.20, N = 532; moderate-quality evidence). The SSRIs were the only medication proving effective in reducing relapse based on moderate-quality evidence. We assessed tolerability of SSRIs and the serotonin and norepinephrine reuptake inhibitor (SNRI) venlafaxine on the basis of treatment withdrawal; this was higher for medication than placebo (SSRIs: k = 24, RR 2.59; 95% CI 1.97 to 3.39, N = 5131, low-quality evidence; venlafaxine: k = 4, RR 3.23; 95% CI 2.15 to 4.86, N = 1213, moderate-quality evidence), but there were low absolute rates of withdrawal for both these medications classes compared to placebo. We did not find evidence of a benefit for the rest of the medications compared to placebo.For the secondary outcome of SAnD symptom severity, there was benefit for the SSRIs, the SNRI venlafaxine, MAOIs, RIMAs, benzodiazepines, the antipsychotic olanzapine, and the noradrenergic and specific serotonergic antidepressant (NaSSA) atomoxetine in the reduction of SAnD symptoms, but most of the evidence was of very low quality. Treatment with SSRIs and RIMAs was also associated with a reduction in depression symptoms. The SSRIs were the only medication class that demonstrated evidence of reduction in disability across a number of domains.We observed a response to long-term treatment with medication for the SSRIs (low-quality evidence), for the MAOIs (very low-quality evidence) and for the RIMAs (moderate-quality evidence).

AUTHORS' CONCLUSIONS

We found evidence of treatment efficacy for the SSRIs, but it is based on very low- to moderate-quality evidence. Tolerability of SSRIs was lower than placebo, but absolute withdrawal rates were low.While a small number of trials did report treatment efficacy for benzodiazepines, anticonvulsants, MAOIs, and RIMAs, readers should consider this finding in the context of potential for abuse or unfavourable side effects.