Harvard Study: CBD May Significantly Reduce Anxiety With Minimal Side Effects

A new study provides evidence “supporting efficacy and tolerability of a full-spectrum, high-CBD product for anxiety.”

Published in the journal Communications Medicine and conducted by researchers at Harvard Medical School, the study is titled Clinical and cognitive improvement following full-spectrum, high-cannabidiol treatment for anxiety: open-label data from a two-stage, phase 2 clinical trial.

The study notes that although “evidence suggests cannabidiol (CBD) has anxiolytic properties, indicating potential for novel treatment strategies… few clinical trials of CBD-based products have been conducted, and none thus far have examined the impact of these products on cognition.”

For the this open-label clinical trial, autoregressive linear modeling assessed the efficacy and tolerability of a four-week regime of a full-spectrum, high-CBD, low-THC extract (9.97 mg/mL CBD to 0.23 mg/mL Δ-9-tetrahydrocannabinol) in outpatients with moderate-to-severe anxiety.

“Findings suggest significant improvement on primary outcomes measuring anxiety and secondary outcomes assessing mood, sleep, quality of life, and cognition (specifically executive function) following treatment”, states the study. “Anxiety is significantly reduced at week 4 relative to baseline. Clinically significant treatment response is achieved and maintained as early as week 1 in most patients; cumulative frequency of treatment responders reached 100% by week 3.”

Researchers state that the CBD is “well-tolerated, with high adherence/patient retention and no reported intoxication or serious adverse events. Minor side effects, including sleepiness/fatigue, increased energy, and dry mouth are infrequently endorsed.”

The study concludes: “Results provide preliminary evidence supporting efficacy and tolerability of a full-spectrum, high-CBD product for anxiety. Patients quickly achieve and maintain symptom reduction with few side effects. A definitive assessment of the impact of this novel treatment on clinical symptoms and cognition will be ascertained in the ongoing double-blind, placebo-controlled stage.”

The full abstract can be found below.

Abstract

Background: Evidence suggests cannabidiol (CBD) has anxiolytic properties, indicating potential for novel treatment strategies. However, few clinical trials of CBD-based products have been conducted, and none thus far have examined the impact of these products on cognition.

Methods: For the open-label stage of clinical trial NCT02548559, autoregressive linear modeling assessed efficacy and tolerability of four-weeks of 1 mL t.i.d. treatment with a full-spectrum, high-CBD sublingual solution (9.97 mg/mL CBD, 0.23 mg/mL Δ-9-tetrahydrocannabinol) in 14 outpatients with moderate-to-severe anxiety, defined as ≥16 on the Beck Anxiety Inventory (BAI) or ≥11 on the Overall Anxiety Severity and Impairment Scale (OASIS).

Results: Findings suggest significant improvement on primary outcomes measuring anxiety and secondary outcomes assessing mood, sleep, quality of life, and cognition (specifically executive function) following treatment. Anxiety is significantly reduced at week 4 relative to baseline (BAI: 95% CI = [-21.03, -11.40], p < 0.001, OASIS: 95% CI = [-9.79, -6.07], p < 0.001). Clinically significant treatment response (≥15% symptom reduction) is achieved and maintained as early as week 1 in most patients (BAI = 78.6%, OASIS = 92.7%); cumulative frequency of treatment responders reached 100% by week 3. The study drug is well-tolerated, with high adherence/patient retention and no reported intoxication or serious adverse events. Minor side effects, including sleepiness/fatigue, increased energy, and dry mouth are infrequently endorsed.

Conclusions: Results provide preliminary evidence supporting efficacy and tolerability of a full-spectrum, high-CBD product for anxiety. Patients quickly achieve and maintain symptom reduction with few side effects. A definitive assessment of the impact of this novel treatment on clinical symptoms and cognition will be ascertained in the ongoing double-blind, placebo-controlled stage.

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