Polymer microdepots delivered full-spectrum cannabis extract over two weeks and reduced seizures in mice | Research

The takeaway

Implantable polymer microdepots provided sustained release of multiple phytocannabinoids from a CBD-rich cannabis extract for over 14 days in mice and reduced seizure severity.

Epilepsy researchers exploring novel cannabinoid delivery methods, pharmaceutical scientists working on sustained-release formulations, and clinicians interested in improving cannabis medication consistency.

170% longer time to first seizure with sustained-release microdepots

What the researchers found

Subcutaneously injected microdepots released CBD and other phytocannabinoids over 14+ days, maintaining elevated serum levels. One week after a single administration, microdepots reduced tonic-clonic seizure incidence by 40%, increased survival by 50%, and delayed seizure onset by 170% compared to a single extract injection.

Why it matters

Current cannabis administration through oral or inhaled routes has variable absorption and short duration. A long-acting delivery system could provide more consistent therapeutic levels and better seizure control.

The numbers in context

Sustained release over 14+ days. At one week: 40% reduction in tonic-clonic seizure incidence, 50% increase in survival rate, 170% increase in latency to first seizure.

How the study worked

Melt-printed polymeric microdepots encapsulating CBD-rich full-spectrum cannabis extract were injected subcutaneously in mice. Serum phytocannabinoid levels were tracked over time. Efficacy was tested in a pentylenetetrazol-induced seizure model comparing microdepots vs. single extract injection.

What this study cannot tell us

Animal study in a chemically induced seizure model, which differs from human epilepsy. Subcutaneous implantation may not be acceptable to all patients. Long-term biocompatibility of the polymer was not assessed.

How to read the evidence

Preclinical proof-of-concept study in mice. Novel delivery technology with promising results but no human data.

When this study was published

2020 study. Early-stage drug delivery research that could inform future clinical formulations of cannabis-based medicines.

The bigger picture

Drug delivery technology applied to cannabis could overcome some of the biggest limitations of current medical cannabis use: inconsistent dosing, variable bioavailability, and the need for frequent administration.

Questions still open

Would these microdepots work similarly in humans? Could the technology be adapted for other cannabinoid formulations or conditions? What would the optimal release duration be for clinical use?

Common questions

What are microdepots?

Microdepots are tiny polymer structures that slowly release encapsulated drugs over an extended period. In this study, they were injected under the skin and released cannabis extract components for over two weeks.

Why use full-spectrum extract instead of pure CBD?

Full-spectrum extracts contain multiple cannabinoids in specific ratios, which some research suggests may provide enhanced therapeutic effects compared to isolated compounds, sometimes called the "entourage effect."

Read the original research

Full-Spectrum Cannabis Extract Microdepots Support Controlled Release of Multiple Phytocannabinoids for Extended Therapeutic Effect.

ACS applied materials & interfaces, 12(21), 23707-23716

View on PubMed ↗Publisher’s paper ↗

Citation

Uziel, Almog; Gelfand, Anat; Amsalem, Keren; Berman, Paula; Lewitus, Gil M; Meiri, David; Lewitus, Dan Y. (2020). Full-Spectrum Cannabis Extract Microdepots Support Controlled Release of Multiple Phytocannabinoids for Extended Therapeutic Effect.. ACS applied materials & interfaces, 12(21), 23707-23716. https://doi.org/10.1021/acsami.0c04435