Current and future approaches for clinical research with CBD in
anxiety-related
disorders
Based on this positive background of preclinical data, anecdote and case
reports, and small randomised controlled trials, numerous clinical
trials are currently registered (see
clinicaltrials.gov) assessing the
potential of CBD in anxiety-related disorders. There are three phase 2
trials registered assessing the ability of CBD to reduce general anxiety
(NCT02548559, NCT04267679, NCT04286594), one phase 3 clinical trial in
generalised anxiety disorder (NCT03549819), one phase 2 trial in social
anxiety disorder (NCT04086342), three phase 2 trials in PTSD
(NCT03518801, NCT03248167, NCT04197102), one phase 3 trial in bipolar
depression (NCT03310593), and one phase 1 trial to assess reducing
anxiety in Alzheimer’s Disease (NCT04075435).
Due to the intrinsic issues hindering the effective use of CBD as an
oral drug in the solid-state, such as polymorphism, low solubility and
bioavailability, and pharmacokinetic variability, some researchers are
looking to improve on the physicochemical characteristics of the CBD
molecule. Engineering of the crystalline structure of drug molecules by
cocrystalization is a well-developed pharmaceutical strategy of enhanced
pharmaceutics . Cocrystals are defined as crystalline materials composed
of two or more molecules within the same crystal lattice (FDA Guidance
for Industry, 2016). A cocrystal composition of CBD has the potential to
overcome numerous physicochemical issues, allowing improved stability
and bioavailability. Considerations for selection of the appropriate
coformer, to form the CBD cocrystal, for a particular application, such
as PTSD, include the properties of inert or pharmacologically active
coformers. CBD cocrystal coformers such as tetramethylpyrazine (TMP)
that have some evidence of activity in anxiety related disorders or
PTSD, may be particularly attractive , and have been patented by Artelo
Biosciences for development in this area.