Australian researchers improve CBD bioavailability

Researchers at the University of South Australia claim to have succeeded in significantly increasing the solubility of cannabidiol (CBD) and improving its absorption in the gastrointestinal tract.

Indeed, one of the challenges of its consumption is bioavailability. when ingested orally, that is, the proportion likely to be absorbed by the body. Low bioavailability (around 6% in humans) results from poor water solubility, physicochemical instability and high first-pass metabolism.

Although progress has been made in terms of bioavailability, it has been limited. For example, oil-based formulations are commonly used for the oral administration of CBD, and they provide only a 14% increase over lipid-free formulations.

But a UniSA team led by Professor Sanjay Garg reports having identified the optimal composition of phospholipids (lipids containing a phosphate group) to form nanometric CBD-PLC particles with a six-fold increase in solubility and dissolution. And in cellular studies of CBD-PLC, their development showed higher 32.7 % permeability, enabling greater absorption through the intestinal wall.

«Improved bioavailability means that lower doses can achieve the same therapeutic effect, which can reduce side effects and make treatment more cost-effective.», said the study's first author, Thabata Muta, a doctoral candidate at UniSA.

Moreover, while conventional CBD formulations degrade over time when exposed to heat, light or oxygen, tests carried out over a one-year period showed that CBD-PLC retained its performance under different storage conditions: 4°C, 25°C and 40°C.

A prolonged release of the molecule was also observed, which could offer therapeutic benefits by maintaining plasma concentrations over a prolonged period. In addition to CBD, the general approach could be applied to other poorly water-soluble substances to improve their absorption.

«The results indicate that CBD-PLC improves CBD solubility, permeability and stability, providing a promising strategy to address the limitations of oral CBD delivery systems,» says the study report.

Armed with the results of its work, the UniSA research team is now studying the possibilities of commercialization and clinical trials to validate this new formulation.

The study has been published in the’International Journal of Molecular Sciences.