A Neuroanatomic and Pathophysiologic Framework for Novel Pharmacological Approaches to the Treatment of Post-traumatic Stress Disorder.

Post-traumatic stress disorder (PTSD) is a debilitating disorder inflicting high degrees of symptomatic and socioeconomic burdens. The development of PTSD results from a cascade of events with contributions from multiple processes and the underlying pathophysiology is complex, involving neurotransmitters, neurocircuitry, and neuroanatomical pathways. Presently, only two medications are US FDA-approved for the treatment of PTSD, both selective serotonin reuptake inhibitors (SSRIs). However, the complex underlying pathophysiology suggests a number of alternative pathways and mechanisms that may be targets for potential drug development. Indeed, investigations and drug development are proceeding in a number of these alternative, non-serotonergic pathways in an effort to improve the management of PTSD. In this manuscript, the authors introduce novel and emerging treatments for PTSD, including drugs in various stages of development and clinical testing (BI 1358894, BNC-210, PRAX-114, JZP-150, LU AG06466, NYV-783, PH-94B, SRX246, TNX-102), established agents and known compounds being investigated for their utility in PTSD (brexpiprazole, cannabidiol, doxasoin, ganaxolone, intranasal neuropeptide Y, intranasal oxytocin, tianeptine oxalate, verucerfont), and emerging psychedelic interventions (ketamine, MDMA-assisted psychotherapy, psilocybin-assisted psychotherapy), with an aim to examine and integrate these agents into the underlying pathophysiological frameworks of trauma-related disorders.

Effect of Pharmacogenomic Testing for Drug-Gene Interactions on Medication Selection and Remission of Symptoms in Major Depressive Disorder: The PRIME Care Randomized Clinical Trial.

Importance: Selecting effective antidepressants for the treatment of major depressive disorder (MDD) is an imprecise practice, with remission rates of about 30% at the initial treatment. Objective: To determine whether pharmacogenomic testing affects antidepressant medication selection and whether such testing leads to better clinical outcomes. Design, Setting, and Participants: A pragmatic, randomized clinical trial that compared treatment guided by pharmacogenomic testing vs usual care. Participants included 676 clinicians and 1944 patients. Participants were enrolled from 22 Department of Veterans Affairs medical centers from July 2017 through February 2021, with follow-up ending November 2021. Eligible patients were those with MDD who were initiating or switching treatment with a single antidepressant. Exclusion criteria included an active substance use disorder, mania, psychosis, or concurrent treatment with a specified list of medications. Interventions: Results from a commercial pharmacogenomic test were given to clinicians in the pharmacogenomic-guided group (n = 966). The comparison group received usual care and access to pharmacogenomic results after 24 weeks (n = 978). Main Outcomes and Measures: The co-primary outcomes were the proportion of prescriptions with a predicted drug-gene interaction written in the 30 days after randomization and remission of depressive symptoms as measured by the Patient Health Questionnaire-9 (PHQ-9) (remission was defined as PHQ-9 ≤ 5). Remission was analyzed as a repeated measure across 24 weeks by blinded raters. Results: Among 1944 patients who were randomized (mean age, 48 years; 491 women [25%]), 1541 (79%) completed the 24-week assessment. The estimated risks for receiving an antidepressant with none, moderate, and substantial drug-gene interactions for the pharmacogenomic-guided group were 59.3%, 30.0%, and 10.7% compared with 25.7%, 54.6%, and 19.7% in the usual care group. The pharmacogenomic-guided group was more likely to receive a medication with a lower potential drug-gene interaction for no drug-gene vs moderate/substantial interaction (odds ratio [OR], 4.32 [95% CI, 3.47 to 5.39]; P < .001) and no/moderate vs substantial interaction (OR, 2.08 [95% CI, 1.52 to 2.84]; P = .005) (P < .001 for overall comparison). Remission rates over 24 weeks were higher among patients whose care was guided by pharmacogenomic testing than those in usual care (OR, 1.28 [95% CI, 1.05 to 1.57]; P = .02; risk difference, 2.8% [95% CI, 0.6% to 5.1%]) but were not significantly higher at week 24 when 130 patients in the pharmacogenomic-guided group and 126 patients in the usual care group were in remission (estimated risk difference, 1.5% [95% CI, -2.4% to 5.3%]; P = .45). Conclusions and Relevance: Among patients with MDD, provision of pharmacogenomic testing for drug-gene interactions reduced prescription of medications with predicted drug-gene interactions compared with usual care. Provision of test results had small nonpersistent effects on symptom remission. Trial Registration: ClinicalTrials.gov Identifier: NCT03170362.

Biomarker Response to Mindfulness Intervention in Veterans Diagnosed with Post-traumatic Stress Disorder.

Objectives: This study evaluates the effects of treatment with mindfulness-based stress reduction (MBSR) compared to the active control, present-centered group therapy (PCGT), on morning plasma cortisol, interleukin-6 (IL-6), and C-reactive protein (CRP) in veterans diagnosed with post-traumatic stress disorder (PTSD). Methods: In a post hoc exploratory analysis, we pooled biomarkers and clinical outcomes of mindfulness, PTSD, and depression from two randomized controlled trials comparing MBSR (n = 104) to PCGT (n = 106) in U.S. military veterans diagnosed with PTSD. Linear mixed-effects modeling was used to evaluate associations between changes in biomarkers and clinical outcomes from baseline to 9-week primary endpoint and 16-week follow-up endpoint. Results: Cortisol levels were inversely related to self-reported PTSD symptoms at baseline (p = 0.02). Cortisol increased from baseline to 9-week endpoint for both groups, but significantly less so in the MBSR group compared to PCGT group (mean difference 1.69 ± 0.8 SE; p = 0.035). Changes in IL-6 and CRP did not differ between groups at either baseline or week 9. From baseline to week 9, increased mindfulness was significantly associated with increased cortisol (p = 0.02) and decreased PTSD and depression severity (p < 0.01). Increased IL-6 and CRP were significantly associated with decreased PTSD severity (p < 0.05), but not depression. Pooled analysis corroborated earlier findings that MBSR is significantly better than PCGT in improving clinical outcomes. Increased mindfulness was strongly associated with improved symptoms. Conclusions: Increased mindfulness is associated with a recalibration of cortisol levels which may be indicative of therapeutic response, especially in patients with lower baseline cortisol. Furthermore, mindfulness-based practices improve symptoms of PTSD and depression in a significant correlation with self-reported levels of mindfulness. Clinical Trial Registration clinicaltrialsgov: NCT01532999 and NCT01548742.

Ziprasidone Augmentation of SSRI Antidepressants in Posttraumatic Stress Disorder: A Randomized, Placebo-Controlled Pilot Study of Augmentation Therapy.

BACKGROUND: Posttraumatic stress disorder (PTSD) is often a chronic, disabling illness for which antidepressant medications (ie, SSRI) are considered the primary psychopharmacological treatment. However, many patients remain refractory to antidepressants alone or in combination with psychotherapy. Safe and effective treatments for individuals with refractory PTSD are needed. This study aimed to examine ziprasidone augmentation of SSRI treatment of PTSD. METHODS: This was a 2-phase study. In phase 1, subjects were treated with paroxetine or sertraline for 8 weeks. Individuals refractory to the SSRI treatment then entered into phase II of the study and were randomized, in a double-blind fashion, to 8 weeks of treatment with either ziprasidone or placebo. The primary outcome measure was change in Clinician Administered PTSD Scale total scores with the intent-to-treat sample. Secondary outcome measures included Positive and Negative Syndrome Scale scores, measures of depression and anxiety, and safety measures. RESULTS: No significant differences were observed on the Clinician Administered PTSD Scale, Positive and Negative Syndrome Scale, or other outcome measures between ziprasidone and placebo groups. No significant differences were observed for safety measures including metabolic profiles, extrapyramidal symptoms/movement disorder rating scales, nor study dropout. CONCLUSIONS: Although no significant differences were noted in efficacy or safety measures between ziprasidone and placebo in this pilot study, the small sample size prevents definitive conclusions.

A Multisite Randomized Controlled Trial of Mindfulness-Based Stress Reduction in the Treatment of Posttraumatic Stress Disorder.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is often difficult to treat, and many patients do not achieve full remission. Complementary and integrative health approaches, such as mindfulness meditation, are intended to be integrated with evidence-based treatment. This study examined the efficacy of mindfulness-based stress reduction (MBSR) in the treatment of PTSD in U.S. military veterans. METHODS: Veterans with a diagnosis of PTSD (N=214) were randomly assigned to either 90-minute group MBSR or present-centered group therapy (PCGT) for eight weeks. Follow-up assessments were obtained at baseline and weeks 3, 6, 9 (primary endpoint), and 16. RESULTS: Both the MBSR and PCGT groups achieved significant improvement in PTSD as measured by the Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV), with no statistically significant differences between groups. However, compared with PCGT, the MBSR group showed a statistically significant improvement in PTSD on the self-reported PTSD Checklist for DSM-IV over the nine weeks. This difference was not maintained posttreatment, at week 16. Strengths of the study include its large sample size, multisite design, active control group, single-blind outcome ratings, fidelity monitoring, large minority representation, and randomized approach. The study was limited by its high attrition rate and low representation of women. CONCLUSION: Both MBSR and PCGT appear to have beneficial effects in treating PTSD in veterans, with greater improvement observed in self-reported PTSD symptoms in the MBSR group. No differences between groups were observed on the CAPS-IV scale.

Characterizing the Effects of Quetiapine in Military Post-Traumatic Stress Disorder.

Objectives: A previous randomized placebo-controlled trial in military veterans posttraumatic stress disorder (PTSD) found that quetiapine improved global PTSD symptoms severity, depression and anxiety as well as the re-experiencing and hypearousal clusters. However, it is not known if individual symptoms had a preferential response to this medication. The goal of this study was to analyze the individual symptom response in this group of patients. Methods: Data from a previous trial was re-analyzed. Each of the of the scale items was analyzed individually using Repeated Measures Analysis of Variance. Results: Compared to placebo, there was a significant decline in the Clinician-Administered PTSD Scale intrusive memories and insomnia questions. In the Davidson Trauma Scale, greater improvements were observed on irritability, difficulty concentrating, hyperstartle and a trend was observed on avoiding thoughts or feelings about the event. Greater improvements compared with placebo were noted on the Hamilton Depression (HAM-D) middle and late insomnia items. On the Hamilton Anxiety scale (HAM-A), the insomnia item was significantly improved. Conclusions: Quetiapine demonstrated greater effect than placebo on several symptoms. The strongest response was seen on insomnia, which the highest significance level on the CAPS. The insomnia items of both the HAM-D and HAM-A also demonstrated improvement with quetiapine. These finding indicate quetiapine improved sleep measure. Insomnia can be a difficult problem to treat in PTSD patients, therefore quetiapine should be considered in difficult cases.

Augmenting treatment efficiency in exposure therapy for PTSD: a randomized double-blind placebo-controlled trial of yohimbine HCl.

The alpha-2 adrenergic receptor antagonist, yohimbine, can facilitate fear extinction in animals and humans. One potential mechanism is increased noradrenergic activity and associated arousal in the presence of conditioned stimuli. Accordingly, yohimbine might augment prolonged exposure (PE) therapy for posttraumatic stress disorder (PTSD), where heightened exposure-oriented arousal is a theorized driver and empirical predictor of treatment success. A double-blind placebo-controlled randomized trial (NCT 01031979) piloted yohimbine augmentation in 26 males with combat-related PTSD. Participants were given one-time dose of yohimbine or placebo prior to the first imaginal exposure. Subsequently, both arms completed standard PE. The primary outcome was trauma-cued heart-rate reactivity a week after the drug/exposure visit, a highly specified, objective measure sensitive to incremental change. Secondary outcomes included arousal during the drug/exposure visit and slope of distress, PTSD, and depression over the course of PE. Consistent with hypothesis, yohimbine led to higher objective and subjective arousal during the drug/exposure visit and to lower trauma-cued heart-rate reactivity one-week later. One dose of yohimbine also led to greater between-session habituation and more rapid improvement on depression, but not PTSD, over the course of care. Results of this controlled pilot indicate support for continued investigation of yohimbine-augmented exposure therapy for PTSD.

A randomized controlled trial of ganaxolone in posttraumatic stress disorder.

Preclinical and clinical research supports a role for neuroactive steroids in the pathophysiology of posttraumatic stress disorder (PTSD). We investigated ganaxolone (a synthetic 3ß-methylated derivative of allopregnanolone, a GABAergic neuroactive steroid) for treatment of PTSD in a proof-of-concept, multisite, double-blind, placebo-controlled trial. Veteran and non-veteran participants (n = 112) were randomized to ganaxolone or placebo at biweekly escalating doses of 200, 400, and 600 mg twice daily for 6 weeks. During an open-label 6-week extension phase, the initial ganaxolone group continued ganaxolone, while the placebo group crossed over to ganaxolone. Eighty-six and 59 participants, respectively, completed the placebo-controlled and open-label phases. A modified intent-to-treat mixed model repeated measures analysis revealed no significant differences between the effects of ganaxolone and placebo on Clinician Administered PTSD Symptom (CAPS) scores, global well-being, negative mood, or sleep. Dropout rates did not differ between groups, and ganaxolone was generally well tolerated. Trough blood levels of ganaxolone at the end of the double-blind phase were, however, lower than the anticipated therapeutic level of ganaxolone in >35% of participants on active drug. Pharmacokinetic profiling of the ganaxolone dose regimen used in the trial and adverse event sensitivity analyses suggest that under-dosing may have contributed to the failure of ganaxolone to out-perform placebo. Future investigations of ganaxolone may benefit from higher dosing, rigorous monitoring of dosing adherence, a longer length of placebo-controlled testing, and targeting of treatment to PTSD subpopulations with demonstrably dysregulated pre-treatment neuroactive steroid levels. Clinicaltrials.gov identifier: NCT01339689.

A Double-Blind, Randomized, Controlled Pilot Trial of N-Acetylcysteine in Veterans With Posttraumatic Stress Disorder and Substance Use Disorders.

OBJECTIVE: The antioxidant N-acetylcysteine is being increasingly investigated as a therapeutic agent in the treatment of substance use disorders (SUDs). This study explored the efficacy of N-acetylcysteine in the treatment of posttraumatic stress disorder (PTSD), which frequently co-occurs with SUD and shares impaired prefrontal cortex regulation of basal ganglia circuitry, in particular at glutamate synapses in the nucleus accumbens. METHODS: Veterans with PTSD and SUD per DSM-IV criteria (N = 35) were randomly assigned to receive a double-blind, 8-week course of N-acetylcysteine (2,400 mg/d) or placebo plus cognitive-behavioral therapy for SUD (between March 2013 and April 2014). Primary outcome measures included PTSD symptoms (Clinician-Administered PTSD Scale, PTSD Checklist-Military) and craving (Visual Analog Scale). Substance use and depression were also assessed. RESULTS: Participants treated with N-acetylcysteine compared to placebo evidenced significant improvements in PTSD symptoms, craving, and depression (ß values < -0.33; P values < .05). Substance use was low for both groups, and no significant between-group differences were observed. N-acetylcysteine was well tolerated, and retention was high. CONCLUSIONS: This is the first randomized controlled trial to investigate N-acetylcysteine as a pharmacologic treatment for PTSD and SUD. Although preliminary, the findings provide initial support for the use of N-acetylcysteine in combination with psychotherapy among individuals with co-occurring PTSD and SUD. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02499029.

Efficacy of Quetiapine Monotherapy in Posttraumatic Stress Disorder: A Randomized, Placebo-Controlled Trial.

OBJECTIVE: This was a 12-week randomized, placebo-controlled trial to assess the efficacy of quetiapine monotherapy in the treatment of posttraumatic stress disorder (PTSD). METHOD: Eighty patients were randomly assigned to treatment with either quetiapine or placebo. The primary outcome measure was the Clinician-Administered PTSD Scale (CAPS). Secondary efficacy measures included the CAPS subscales, the Davidson Trauma Scale, the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions (CGI) scales for severity of Illness and improvement, the Hamilton Depression Rating Scale (HAM-D), and the Hamilton Anxiety Rating Scale (HAM-A). Safety measurements included adverse events, vital signs, the Abnormal Involuntary Movement Scale, the Barnes Akathisia Scale, the Simpson-Angus Scale, and the Arizona Sexual Experiences Scale. RESULTS: After a 1-week placebo run-in, quetiapine was started at a daily dosage of 25 mg and increased to a maximum of 800 mg; the average was 258 mg (range, 50-800 mg). Reductions in CAPS total, re-experiencing, and hyperarousal scores were significantly greater for the quetiapine group than for the placebo group. Greater improvements were also observed for quetiapine in scores on the Davidson Trauma Scale, CGI severity and improvement ratings, PANSS positive symptom and general psychopathology subscales, HAM-A, and HAM-D than for placebo. Adverse events were generally mild and expected based on prior studies of quetiapine in this and other patient population. There were no differences in safety measures between groups. CONCLUSION: Quetiapine monotherapy was efficacious in the treatment of PTSD. These findings suggest quetiapine as a single agent is effective in treating military PTSD.

The role of PTSD in adjudicating violent crimes.

PTSD was formalized as a diagnosis by the American Psychiatric Association in 1980 with the publication of the Diagnostic and Statistical Manual of Mental Disorders (DSM), 3rd edition. Since that time, the diagnosis has been widely utilized in the courts including the use in criminal proceedings. PTSD may play a role in the assessment of violent crimes both as a possible contributing factor in the perpetrators as well as a consequence in the victims. There are a number of ethical and clinical considerations in the use of this diagnosis. Importantly, the diagnostic criteria have changed to a degree with subsequent editions of the DSM. This may have an impact on the interpretation of past legal judgments. Moreover, extensive psychiatric comorbidity may complicate the clinical picture, e.g., mood disorders, substance use disorders, or psychosis. The diagnosis of PTSD is still based on clinical, largely subjective criteria, e.g., biological markers are not yet utilized. As such, there may not be consistent agreement about the diagnosis among experts. This paper summarizes some of these relevant issues in adjudicating violent crimes.

ALTERED BLOOD SPHINGOLIPIDOMICS AND ELEVATED PLASMA INFLAMMATORY CYTOKINES IN COMBAT VETERANS WITH POST-TRAUMATIC STRESS DISORDER.

Patients with post-traumatic stress disorder (PTSD) have greater risk of developing cardiovascular disease (CVD). While chronically elevated plasma cholesterol and pro-inflammatory cytokines levels increase CVD risk, several studies have shown that cholesterol reduction does not reduce CVD risk. Acid sphingomyelinase (ASMase) activation has been implicated in both CVD and major depressive disorder. We investigated plasma pro-inflammatory cytokine levels, ASMase activity, and changes in sphingolipids in PTSD patients compared to healthy controls. Levels of interleukin 6, interleukin 10, interferon-γ and tumor necrosis factor-α were higher in PTSD patients than controls. Plasma ASMase activity and sphingosine 1-phosphate were higher in the PTSD group (1.6-fold and 2-fold, respectively; p<0.05). The results suggest that CVD risk factors in PTSD patients remain high despite cholesterol reduction.

Diagnosis and treatment of PTSD-related compulsive checking behaviors in veterans of the Iraq war: the influence of military context on the expression of PTSD symptoms.

This case study presents an overview of the conceptualization and treatment of two veterans of the Iraq War who presented for combat-related treatment at a Veterans Administration Medical Center. In addition to posttraumatic stress disorder (PTSD) symptoms of reexperiencing, arousal, and avoidance, the veterans exhibited compulsive checking behaviors that appear to be influenced by theater-specific combat duties and traumatic events. These cases represent what the authors believe to be an increasingly common expression of PTSD in veterans of the Iraq and Afghanistan wars. Both veterans were treated with prolonged exposure therapy, which includes imaginal and in vivo exposure to anxiety-provoking stimuli, processing of traumatic events, and self-assessment of anxiety. Treatment also included in vivo exposure with response prevention techniques borrowed from the literature on obsessive-compulsive disorder to address compulsive checking behaviors within the ecological context of each patient's symptom presentation. Measures related to PTSD and depression were obtained before, during, and after treatment. Treatment was associated with significant declines in symptom severity and improved functioning for both veterans. The unique nature of the conflict in the Middle East represents role challenges for soldiers that affect symptom presentation. Variations in symptom presentation can in turn complicate efforts to identify and appropriately address PTSD-related health concerns in this population. Thus, clinicians and researchers must remain cognizant of how theater-specific duties influence the manifestation and treatment of PTSD in order to provide optimal care to a new generation of veterans.

A preliminary controlled trial of divalproex in posttraumatic stress disorder.

BACKGROUND: Case reports and open trials have reported beneficial effects of divalproex in the treatment of posttraumatic stress disorder (PTSD). The objective of this study was to conduct a placebo-controlled study of the efficacy and tolerability of divalproex in chronic PTSD patients. METHODS: Patients were randomized to receive placebo or divalproex. The primary outcome measure was the Clinician Administered PTSD Scale (CAPS). RESULTS: Of 29 patients randomized, 16 received divalproex and 13 placebo. There were no significant differences between groups in mean change from baseline to end point (last observation carried forward) on the CAPS total score or subscales except for a significant decrease in avoidance/numbing scores with placebo. The only significant difference in secondary outcomes was a greater improvement in Clinical Global Impression Scale-Severity favoring placebo. CONCLUSIONS: Divalproex was not superior to placebo in this study. This could be due to lack of efficacy of divalproex in this population, inadequate sample size to detect differences, or other factors. Further study of divalproex is needed to better clarify the role of this agent in PTSD.

An open-label assessment of aripiprazole in the treatment of PTSD.

BACKGROUND: Recent studies suggest that atypical antipsychotics may be effective augmentation strategies for the treatment of posttraumatic stress disorder (PTSD). Limited data were available on the newest agent, aripiprazole, so we aimed to evaluate its efficacy and tolerability in the treatment of PTSD. METHODS: A 12-week, prospective, open-label, flexible-dose, adjunctive trial of aripiprazole was conducted in military veterans meeting DSM-IV criteria for PTSD. Concomitant psychiatric medications continued unchanged, except for other neuroleptics which were not allowed. The primary outcome variable was change from baseline in the Clinician Administered PTSD scale (CAPS). RESULTS: All 17 subjects were male, with an average age of 57 years. Total CAPS scores decreased from 78.2 (SD = 17.8) at baseline to 60.0 (23.5) at study end (p = 0.002). Re-experiencing (CAPS-B) and avoidance/numbing symptoms (CAPS-C) were significantly improved, and trend level reductions were observed in hyperarousal symptoms (CAPS-D). Fifty-three percent (9/17) were considered responders, as defined by a decrease in total CAPS scores of at least 20%. Reductions in the Positive and Negative Symptom Scale (PANSS) total score and positive and general psychopathology subscale scores were statistically significant. The final average dose of aripiprazole was 13.06 (SD = 6.45) mg daily. Nine patients discontinued because of side effects. The most common adverse events consisted of gastro-intestinal disturbances, sedation, and psychomotor activation. Tolerability was improved with lower starting doses (e.g., 5 mg daily) and slow titration. CONCLUSIONS: Addition of aripiprazole to ongoing treatment further reduced PTSD symptoms in military veterans with severe PTSD. These preliminary findings await confirmation in randomized, controlled trials.

A randomized trial of telepsychiatry for post-traumatic stress disorder.

We compared the efficacy of telepsychiatry and same-room treatment of combat-related post-traumatic stress disorder (PTSD) using cognitive behavioural therapy in 14 weekly, 90-min treatment sessions. Of 97 patients referred for study participation, 38 were randomized (17 into telepsychiatry, 21 into same-room), and approximately 25 (the number differed by instrument) had at least one post-baseline assessment. Measures of clinical and process outcomes were examined. No group differences were found on clinical outcomes at three-month follow-up. Satisfaction with treatment ratings was similar in both groups, with 'strong satisfaction' indicated by veterans in both modalities. Attendance and drop-out were similar in the two groups. The same-room group reported more comfort in talking with their therapist at post-treatment and had better treatment adherence. The results provide preliminary support for the use of telepsychiatry in the treatment of PTSD to improve access to care.

Open-label trial of escitalopram in the treatment of posttraumatic stress disorder.

BACKGROUND: Posttraumatic stress disorder (PTSD) is a highly prevalent, disabling illness. Selective serotonin reuptake inhibitors (SSRIs) are considered first-line medication treatment, with sertraline, paroxetine, and fluoxetine being the most studied. More limited but favorable data suggest that citalopram, an SSRI, may also have a role in the treatment of PTSD. Its S-enantiomer escitalopram, which may have faster onset and greater magnitude of effect than citalopram in other conditions, has not yet been investigated in PTSD. OBJECTIVE: To assess the efficacy, safety, and tolerability of escitalopram in the treatment of PTSD. METHOD: A 12-week, prospective, open-label trial of escitalopram was conducted from January 2003 through August 2004 in military veterans with PTSD. Escitalopram was initiated at 10 mg daily for 4 weeks, then increased to 20 mg daily for the remainder of the study. Concomitant psychiatric medications were discontinued at least 2 weeks prior to enrollment. The primary outcome variable was the change from baseline to endpoint in global Clinician-Administered PTSD Scale-Symptom version (CAPS-SX) score. Secondary efficacy measures included the Clinical Global Impressions-Severity of Illness (CGI-S) and -Improvement (CGI-I) scales, the Hamilton Rating Scale for Depression (HAM-D), and the Davidson Trauma Scale (DTS). Posttraumatic stress disorder and comorbid diagnoses were established using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. RESULTS: Twenty-four of 25 patients were evaluated for efficacy. The mean global CAPS-SX score decreased from 79.4 (SD = 15.7) at baseline to 61.2 (SD = 24.7) at the end of the study (p = .0002). The CAPS-C avoidance/numbing and CAPS-D hyper-arousal subscale scores decreased significantly from baseline to endpoint (CAPS-C, p = .0171; CAPS-D, p = .0001), with trend-level reductions observed in CAPS-B reexperiencing subscale scores (p = .0593). Forty-five percent of patients (9/20) were much or very much improved at the end of the study (CGI-I of 1 or 2). The HAM-D and DTS also significantly improved (p = .0063 and p = .0004, respectively). Mild to moderate gastrointestinal disturbances were the most common side effects. Only 4 patients discontinued early because of adverse effects. CONCLUSIONS: This preliminary open-label study suggests that escitalopram is both efficacious and well tolerated in PTSD patients. However, randomized controlled studies are needed to confirm these results and to further define its potential role in the treatment of PTSD.