The science and research behind cannabinoids

Professor Ben Whalley explains the science and research behind cannabinoids

Greenwich Biosciences’ Spotlight highlights various aspects of our scientific research and cannabinoid clinical development program. We bring forward the voices of our dedicated employees and members of the medical, caregiver and advocacy community who make an invaluable contribution to our efforts.

This month’s Spotlight features a Q&A with Professor Ben Whalley, Director of Research, GW Pharmaceuticals plc.

This article has been modified since its original publication in April 2018 to reflect U.S. regulatory updates.

Q.) What are the most common cannabinoids found in the cannabis plant and how do they differ?

A.) There are over 100 active cannabinoids found within or derived from the cannabis plant. Each of these compounds can have their own active properties and may bind to certain parts of the brain. The two best characterized cannabinoids are tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is a chemical compound that binds to specific brain receptors and has the psychoactive properties that produces a euphoric effect. Conversely, CBD is also derived from the cannabis plant, but lacks the euphoria associated with THC. It doesn't bind to same part of the brain as THC, so it acts in a completely different manner.

Q.) What is the difference between a purified pharmaceutical formulation of CBD and other CBD products available in the public marketplace?

A.) CBD is extracted from specific varieties of cannabis. There are a multitude of CBD oil products, as well as other cannabis and hemp extracts, available at dispensaries in certain states across the U.S. or online. These unregulated products are not the same as an investigational purified pharmaceutical formulation of CBD. Pharmaceutical CBD has been studied as a treatment for certain medical diseases through a robust scientific process that is regulated by the FDA to protect the safety of patients. These clinical studies have been conducted according to the rigorous standard of scientific methodology – with randomization and appropriate blinding.

It’s important that people don’t generalize the data or safety information that comes from the scientific studies on pharmaceutical CBD to unregulated products they can buy at dispensaries or online. Patients need to understand that they are not using the same product.

Q.) What is the significance of having a cannabis plant-based medicine approved by the FDA?

A.) FDA approval is a positive change to the cannabinoid landscape in the U.S. Until October 2018, all compounds or chemicals from the cannabis plant were Schedule 1 substances. Under DEA guidelines this means that the substance had no accepted medical use, lacked accepted safety data, and could not be prescribed for use by patients. An FDA-approved medicine has been ascribed an acceptable medical use and safety for that use has been identified. As a result, it no longer requires special licensing for patients to participate in research with that medicine. It is available in all 50 states, as each of them has rescheduled it appropriately. It is a prescription medicine that can be treated like any other FDA-approved medications that have been tested and studied through the same rigorous process and manufactured through current Good Manufacturing Practice (cGMP).

Q.) How will the first plant-derived prescription cannabinoid medicine impact patient care?

A.) The medical community believes in the scientific process and evidence-based medicine. With an FDA-approved cannabinoid medicine, physicians gain the security of knowing they can prescribe a treatment that has been rigorously studied and is backed by robust clinical evidence validating its safety and effectiveness. The medicine has passed FDA inspection for quality, stability and consistency: tested to ensure it contains consistent concentrations of cannabinoids and other product ingredients listed on the label.

For evidence-based information about cannabinoids, visit