Generalized Anxiety Disorder
Conditions
Keywords
Anxiety, Chamomile, Herbal Remedy, Complementary and Alternative Medicine
Brief summary
Prior research has shown that chamomile may be an effective, short-term anti-anxiety treatment. This study will examine the initial and long-term benefits of chamomile extract therapy for the prevention of recurrent anxiety disorder.
Detailed description
Anxiety disorders are among the most common psychiatric conditions. They affect up to 25% of the US adult population. Generalized anxiety disorder (GAD) is a chronic, recurrent form of the disorder. Although benzodiazepines and serotonin reuptake inhibitors have become the mainstay therapy of GAD, these drugs are often associated with unwanted side effects, habituation, and withdrawal symptoms. Many individuals decline using conventional drug therapy for financial, cultural, or personal reasons such as the stigma of mental illness. As a result, many individuals will seek alternative therapy for their anxiety symptoms. The identification of effective alternative therapies for GAD would be of particular relevance. Among alternative therapies for anxiety, chamomile has been used as a traditional herbal medicine for its calming effect. It is well tolerated and demonstrates pharmacological activity in animal models of anxiety. Despite its widespread use and availability, there has been only one clinical trial of chamomile safety and efficacy in GAD. The current application seeks to build upon the results of that prior chamomile study. In that 8-week, double-blind, placebo-controlled trial, we found a significant superiority of chamomile (vs. placebo) in reducing GAD symptoms. We also found chamomile to be exceedingly well tolerated (vs. placebo). The current application seeks to extend these promising preliminary results by conducting a randomized, double-blind, parallel group, placebo-substitution, long-term safety and efficacy study of chamomile in preventing GAD relapse. For specific aim #1 we will ask: Does long-term chamomile therapy (vs. placebo) prolong the time to relapse of anxiety symptoms following recovery from GAD? To answer this question, 180 patients with moderate to severe GAD will receive open-label chamomile extract 500-1,500 mg daily for 8 weeks. Responders to chamomile, who remain well for 4 additional weeks of consolidation therapy, will be randomized to double-blind continuation therapy with chamomile 500-1,500 mg daily or placebo for an additional 26 weeks. We hypothesize that continuation chamomile therapy will result in a prolonged time to relapse (vs. placebo). For specific aim #2 we will ask: What is the relative safety and tolerability of long-term chamomile therapy (vs. placebo) in patients who have recovered from GAD? To answer this question, we will examine the following outcome measures: (i) the proportion of patients in each treatment condition who relapse; (ii) the frequency, severity, and duration of treatment-emergent adverse events; (iii) the frequency of discontinuation symptoms during initial double-blind therapy; and, (iv) the frequency of early study discontinuation. We hypothesize that chamomile therapy will result in a lower proportion of anxiety relapses and a lower study discontinuation rate (vs. placebo). We further hypothesize that chamomile therapy will result in a similar frequency of discontinuation symptoms and treatment-emergent adverse events (vs. placebo).
Interventions
500 mg 3 times daily
Sponsors
Study design
Eligibility
Inclusion criteria
* Men and women at least 18 years old (all races and ethnicity) * DSM IV diagnosis of GAD as the primary anxiety disorder * Baseline GAD-7 score ≥ 10 * Baseline CGI/S score at least 4 * Not taking anti-anxiety medication (e.g., Benzodiazepines, buspirone, antidepressants) * Not taking antidepressant, mood stabilizer, or tranquilizer therapy for a prior DSM IV Axis I mood disorder that is in remission * Able to understand and provide informed consent * Able to participate in a 38-week study
Exclusion criteria
* Patients \< 18 years old * Primary DSM IV Axis I anxiety disorder other than GAD (e.g., panic disorder with or without agoraphobia, phobia disorder, acute stress disorder, social anxiety disorder, obsessive-compulsive disorder, post-traumatic stress disorder, substance-induced anxiety disorder) * Current DSM IV Axis I psychotic disorder * Substance abuse or dependence within the prior 3 months * Current DSM IV Axis I bipolar or major depressive disorder \[Note: Patients with co-morbid depressive disorder NOS (e.g., minor depression, recurrent brief depressive disorder, or premenstrual dysphoric disorder (PMDD)\] will not be excluded * Unstable medical condition * Allergy to chamomile * Documented allergy to plants of the asteraceae family (e.g., ragweed, asters, chrysanthemum) * Allergic to mugwort or birch pollen * Concurrent anti-anxiety tranquilizer, antidepressant or mood stabilizer therapy * Concurrent use of over-the-counter anti-anxiety and/or antidepressant preparations (e.g., chamomile, St. John's Wort, kava kava) * Concurrent use of established antidepressant, mood stabilizer, or tranquilizer therapy for pre-existing affective disorder. \[Note: Patients with a history of affective disorder (in remission) who are not currently taking antidepressant, mood stabilizer, or tranquilizer therapy are not excluded from the trial\] * Women of child-bearing potential not willing to use a medically proven form of contraception * Positive pregnancy test * Actively suicidal or suicide attempt within the preceding 12 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time to Relapse in Each Treatment Condition. | 26 weeks | The primary outcome was time to relapse during continuation therapy, analyzed using Cox proportional hazards. Relapse is dichotomously defined as an increase in CGI/S (a clinician-rated global measure of anxiety's severity) score from ≤ 3 (at study visit 6) to ≥ 4 (on two consecutive scheduled or unscheduled study visits ≥ 2 weeks apart) plus meeting DSM IV-TR criteria for GAD (minus the 6-month time criterion). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The Proportion of Subjects in Each Treatment Condition Who Relapse. | 26 weeks | The proportion of subjects in each treatment condition who relapsed after randomization |
| Frequency, Severity, and Duration of Treatment-emergent Adverse Events. | 26 weeks | We will report the frequency, severity, and duration of treatment-emergent adverse events by treatment arm. |
| Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition. | 26 weeks | Discontinuation emergent signs and symptoms checklist (DESS) is a patient-rated measure of the presence and severity of discontinuation symptoms occurring after medication discontinuation. % |
| Frequency of Early Study Discontinuation in Each Treatment Condition. | 26 weeks | This is the # of subjects who discontinued the study during randomization phase due to other reasons. |
Countries
United States
Participant flow
Pre-assignment details
The study has 3 phases. The 1st phase is open label cham.(N=179), subjects meeting response criteria enter 2nd phase (N=93), the consolidation phase of open label chamomile. At the end of 2nd phase, if subjects still meet response criteria, they will enter the 3rd phase (N=93). In the 3rd phase, subjects will be randomized to chamomile vs. placebo.
Participants by arm
| Arm | Count |
|---|---|
| Chamomile Extract Pharmaceutical grade oral chamomile extract.
Chamomile (Matricaria recutita): 500 mg 3 times daily | 46 |
| Placebo Pharmaceutical grade lactose monohydrate.
Chamomile (Matricaria recutita): 500 mg 3 times daily | 47 |
| Total | 93 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 3 | 4 |
| Overall Study | Protocol Violation | 1 | 2 |
| Overall Study | Relasped-reached end point | 7 | 12 |
Baseline characteristics
| Characteristic | Placebo | Chamomile Extract | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 5 Participants | 6 Participants | 11 Participants |
| Age, Categorical Between 18 and 65 years | 42 Participants | 40 Participants | 82 Participants |
| Age, Continuous | 45.4 years STANDARD_DEVIATION 16.1 | 49.2 years STANDARD_DEVIATION 14.3 | 47.3 years STANDARD_DEVIATION 15.3 |
| Region of Enrollment United States | 47 participants | 46 participants | 93 participants |
| Sex: Female, Male Female | 31 Participants | 34 Participants | 65 Participants |
| Sex: Female, Male Male | 16 Participants | 12 Participants | 28 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 8 / 46 | 9 / 47 |
| serious Total, serious adverse events | 0 / 46 | 0 / 47 |
Outcome results
Time to Relapse in Each Treatment Condition.
The primary outcome was time to relapse during continuation therapy, analyzed using Cox proportional hazards. Relapse is dichotomously defined as an increase in CGI/S (a clinician-rated global measure of anxiety's severity) score from ≤ 3 (at study visit 6) to ≥ 4 (on two consecutive scheduled or unscheduled study visits ≥ 2 weeks apart) plus meeting DSM IV-TR criteria for GAD (minus the 6-month time criterion).
Time frame: 26 weeks
Population: All 93 subjects started randomization phase of the study were included in the analysis
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Chamomile Extract | Time to Relapse in Each Treatment Condition. | 11.4 weeks | Standard Deviation 8.4 |
| Placebo | Time to Relapse in Each Treatment Condition. | 6.3 weeks | Standard Deviation 3.9 |
Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition.
Discontinuation emergent signs and symptoms checklist (DESS) is a patient-rated measure of the presence and severity of discontinuation symptoms occurring after medication discontinuation. %
Time frame: 26 weeks
Population: These are responders at the end of Phase II of the study and then were randomized in Phase III of the study
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Chamomile Extract | Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition. | # of subject had no new symptoms after randomizat | 31 Participants |
| Chamomile Extract | Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition. | # of subject had >=1 new symptom after randomizati | 14 Participants |
| Placebo | Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition. | # of subject had no new symptoms after randomizat | 33 Participants |
| Placebo | Frequency of Discontinuation Symptoms at the Start of Double-blind Therapy in Each Treatment Condition. | # of subject had >=1 new symptom after randomizati | 11 Participants |
Frequency of Early Study Discontinuation in Each Treatment Condition.
This is the # of subjects who discontinued the study during randomization phase due to other reasons.
Time frame: 26 weeks
Population: These are responders at the end of Phase II of the study and were then randomized into Phase III of the study.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Chamomile Extract | Frequency of Early Study Discontinuation in Each Treatment Condition. | # Lost to Follow-up | 3 Participants |
| Chamomile Extract | Frequency of Early Study Discontinuation in Each Treatment Condition. | # withdrawn due to non-compliance | 1 Participants |
| Placebo | Frequency of Early Study Discontinuation in Each Treatment Condition. | # Lost to Follow-up | 4 Participants |
| Placebo | Frequency of Early Study Discontinuation in Each Treatment Condition. | # withdrawn due to non-compliance | 2 Participants |
Frequency, Severity, and Duration of Treatment-emergent Adverse Events.
We will report the frequency, severity, and duration of treatment-emergent adverse events by treatment arm.
Time frame: 26 weeks
Population: During phase II consolidation phase, treatment responders were randomized to either 26 weeks of continuation chamomile therapy or placebo.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Chamomile Extract | Frequency, Severity, and Duration of Treatment-emergent Adverse Events. | 8 Participants |
| Placebo | Frequency, Severity, and Duration of Treatment-emergent Adverse Events. | 9 Participants |
The Proportion of Subjects in Each Treatment Condition Who Relapse.
The proportion of subjects in each treatment condition who relapsed after randomization
Time frame: 26 weeks
Population: During phase II consolidation phase, treatment responders were randomized to either 26 weeks of continuation chamomile therapy or placebo.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Chamomile Extract | The Proportion of Subjects in Each Treatment Condition Who Relapse. | 7 Participants |
| Placebo | The Proportion of Subjects in Each Treatment Condition Who Relapse. | 12 Participants |