The FDA has not approved marijuana for any indication, as it continues to retain Schedule I designation. However, a key component of marijuana (D9-Tetrahydrocannabinol or THC) and several synthetic analogues have been approved by the FDA or are under clinical investigation. Whether the FDA will consider approving marijuana in the future will depend, in part, on the prevailing winds in Congress. But as state-after-state legalizes marijuana with the allure of tax revenues, approval seem inevitable, with California be the most notable addition in 2018.
Currently the FDA-approved forms of cannabinoids are Dronabinol, a synthetic form of THC marketed under the tradenames Marinol and Syndros, and Nabilone, a synthetic THC derivative, marketed under the tradename Cesamet.
Several companies are actively evaluating cannabinoid drugs in various stages of development:
- Cara Therapeutics – CR701, a cannabinoid analog for Neuropathic Pain.
- Corbus Pharmaceuticals – Lenabasum, a cannabinoid analog for Cystic Fibrosis and Inflammatory Diseases.
- GW Pharmaceuticals — Cannabidiol (CBD) for Dravet and Lennox-Gastaut Syndromes and other indications.
- GW Pharmaceuticals — THC and CBD mixture for Muscle Stiffness and Spasticity, currently approved in 30 countries (but not the US).
- Insys Therapeutics – CBD for Childhood Absence Epilepsy and Infantile Spasms.
- Zynerba Pharmaceuticals – CBD topical gel for Fragile X Syndrome and Refractory Epilepsy.
- Zynerba Pharmaceuticals – THC Pro-Drug patch for Tourette Syndrome and other Indications.
There is a notable focus on orphan drug indications in this list, suggesting strategic positioning by these companies for streamlined regulatory consideration/approval.  It may take years before cannabis ever gains sufficient traction for FDA review. However, cannabis and CBD edibles (i.e., candies, mints, gummies) may more easily cross into the FDA purview as drug delivery products, as in the case of e-cigarettes.
KCAS has provided bioanalytical support for a synthetic cannabinoid derivative in numerous clinical trials. We are also currently supporting trials for synthetic cannabis formulations. As a personal note, I was involved in the development of assays for Marinol, under grants from the National Cancer Institute. We have special interest in providing GLP-compliant methods and sample analysis support for studies in this area, and know the space well.