University of South Australia researchers report having succeeded in significantly boosted solubility of cannabidiol (CBD) and improving its absorption in the gastrointestinal tract.
A non-intoxicating cannabinoid, cannabidiol is being pursued and used for the management and treatment of a wide range of conditions. Among the challenges in its use is bioavailability when ingested in oral form, which is the proportion that has the potential to be absorbed by the body. Low bioavailability (approximately 6% in humans) is a result of poor water solubility, physicochemical instability, and extensive first-pass metabolism.
While there has been progress made on bioavailability, it has generally been incremental. For example, oil-based formulations are commonly used for oral CBD delivery, and they only provide an increase of 14% compared to lipid-free formulations.
But a UniSA team led by Professor Sanjay Garg report they have identified the optimal phospholipid (a lipid containing a phosphate group) composition to form nanosized CBD-PLC particles that demonstrate a six-fold increase in solubility and dissolution. And in cellular studies of CBD-PLC, their development exhibited 32.7% higher permeability, providing greater absorption through the intestinal wall.
“Improved bioavailability means that lower doses can achieve the same therapeutic effect, potentially reducing side effects and making treatment more cost effective,” said the study’s first author, UniSA PhD candidate Thabata Muta.
Additionally, while conventional formulations of CBD formulations degrade over time when exposed heat, light or oxygen, testing over a year indicated CBD-PLC retained its performance under different storage conditions: 4 °C, 25 °C, and 40 °C.
Also observed was sustained drug release; potentially providing therapeutic advantages through plasma levels being maintained over an extended period. As well as CBD, the general approach has the potential to be applied to other poorly water-soluble drugs to enhance their absorption.
“The results indicate that CBD-PLC improves CBD’s solubility, permeability, and stability, offering a promising strategy to address the limitations of oral CBD delivery systems,” states the study report.
Buoyed by the results of their work, the UniSA research team is now delving into opportunities for commercialisation and clinical trials in order to validate this new formulation.
The study has been published the International Journal of Molecular Sciences.
