Kalytera Therapeutics, clinical-stage pharmaceutical company, recently announced plans for clinical trials focused on the treatment of Graft versus Host Disease using Cannabidiol (CBD), a compound found in cannabis. This development highlights the expanse of continued research—and potential—of CBD-based medicines and methods of treatments being pursued by companies globally.
Cannabis is a flowering plant that has long been recognized for its uses in fiber production and hemp oils, recreation, and medical applications. According to Project CBD, CBD is one of a diverse class of chemicals called cannabinoids found in the cannabis plant. CBD was first identified in the early 1940s , but more than 20 years would pass before researchers identified the more famous cannabinoid, tetrahydrocannabinol (THC). Likely because of its psychoactive effects, THC would go on to dominate research studies of cannabis. However, the classification of marijuana as Schedule I substances under the Controlled Substances Act of 1970, federally sponsored medical research into CBD and its effect dwindled.
Both CBD and THC interact with the human body through the CB1 receptor of the endocannabinoid system, a system of receptors found in the central and peripheral nervous systems and many other organs of the body. The endocannabinoid system is involved in the regulation of, for example, appetite, pain, mood, and memory. By binding more weakly with the CB1 receptor than THC, CBD invokes a different response within the endocannabinoid system. Unlike THC, CBD tends not to cause psychoactive effects. Instead, as a growing body of research suggests, CBD plays a role in moderating the effects of THC and reducing inflammation, nausea and pain. Multiple studies suggest that CBD has therapeutic applications for a wide variety of conditions, and companies across the world are researching medical treatment for specific maladies. A few notable projects evaluating potential uses for CBD include:
- GW Pharmaceuticals has commenced FDA-authorized clinical trials for Epidiolex®, a CBD-based drug for treating a rare genetic epileptic encephalopathy called Dravet syndrome. GW reports to have fourteen distinct patent families with claims directed to treatment of epilepsy. Other GW patent filings for CBD include treatments for constipation and cancer.
- Zynerba Pharmaceuticals is developing a synthetic CBD-based gel that is absorbed through the skin and aimed at treating adult epilepsy, osteoarthritis, and fragile-X syndrome. Zynerba has patents directed to transdermal CBD compositions and other CBD delivery systems.
- Insys Therapeutics, Inc. is in Stage 2 clinical trials for a CBD-based drug to treat severe pediatric epilepsy and applications directed to stable formulations of CBD for oral administration.
- Kannalife Sciences Inc. licenses a U.S. government-owned patent for cannabidiol-based drugs for the treatment of diseases caused by oxidative stress. Kannalife is developing CBD-based drugs for the treatment of Hepatic Encephalopathy and Chronic Traumatic Encephalopathy, a type of brain damage.
- Kalytera reports to have filed composition and method-of-use patents on its CBD treatments.
The science of CBD medicine is still being developed. To date, no CBD-based drug has received FDA approval. According to the DEA, CBD is still considered a Schedule I Controlled Substance by the Drug Enforcement Agency (DEA). As such, the future for CBD producers and researchers is uncertain. Pharmaceutically, CBD presents many challenges to delivery into the body. For example, with a half-life of only 18-32 hours CBD is difficult to stabilize and deliver to a target location within the body. As explained by Kalytera, when taken orally, CBD must pass through the liver, which significantly reduces the bioavailability of CBD. Moreover, CBD is lipophilic and accumulates in the skin when using transdermal delivery. As such, effective delivery of CBD is a significant hurdle.
Despite these challenges, the potential relaxation of legal constraints on cannabis cultivation and sales across the United States and the promise of an entire new field of pharmaceuticals continues to drive innovation in CBD medicine.