Medical and Regulatory Affairs

The Ongoing Quest for Evidence on the Health Effects of Cannabis and Cannabis-Derived Products

Inadequate funding and burdensome regulatory barriers in the United States are two challenges that must be tackled if clinical researchers are to answer important public health questions about the pros and cons of cannabis and cannabinoid use, one of the world’s leading scientific bodies has concluded.

These are among nearly 100 conclusions and recommendations reached in 2017’s most viewed report issued by the National Academies of Sciences, Engineering and Medicine, the independent U.S.-based scientific body collectively referred to as The Academies.  The 320-page consensus study, The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research, is the result of nine months of in-depth work by a special committee that included a review of more than 10,700 relevant scientific abstracts available in English.[1]

The report marked the first major scientific compilation and/or review of cannabis and cannabinoid research in the United States in 18 years. Scientific literature and legal access to cannabis for medical and recreational use has grown significantly since the last review, the report’s committee found, but without the support of collective clinical research standards or a focused national cannabis research agenda they believe is needed.

Cannabis is the most widely used illicit drug in the United States. It remains a Schedule I narcotic under the federal U.S. Controlled Substances Act, and the possession and use of cannabis, even as part of clinical research, remains highly regulated and restricted. In fact, recreational and medical users in the growing number of states where cannabis is legalized often have less trouble obtaining it than clinical researchers who are federally regulated.

Despite many obstacles, the committee determined, there already is “conclusive” or “substantial” evidence in existing research to show that cannabis or cannabinoids provide therapeutic benefit:

  • For the treatment for chronic pain in adults (cannabis)
  • In antiemetic drugs for the treatment of chemotherapy-induced nausea and vomiting (oral cannabinoids)
  • For improving patient-reported multiple sclerosis spasticity symptoms (oral cannabinoids)

They also determined there is “moderate” evidence that cannabis and cannabinoids improve sleep for people with a range of disorders, including chronic pain, sleep apnea, etc., in the short-term.

Much more clinical study must be done to reach definitive conclusions in these and other therapeutic areas, the committee determined. In areas such as epilepsy, obesity, metabolic syndrome, and impacts on the human immune system, the committee found “there exists a paucity of data on the effects of cannabis or cannabinoid-based therapeutics.” Since this report was published, the U.S. Food and Drug Administration approved Epidiolex, a cannabis-derived drug for the treatment of two rare, severe forms of epilepsy.[2] In addition, a cannabis company called GB Sciences is seeking FDA approval for first-in-human clinical trials for a cannabis-based therapy for Parkinson’s disease.

To help advance clinical research and better inform public health decisions, the committee formulated four recommendations:

  1. The need for a national cannabis research agenda that includes clinical and observational research, health policy and health economics research, and public health and public safety research to address key gaps in the evidence base
  2. The need for a set of research standards and benchmarks to guide and ensure the conduct of high-quality research
  3. The need for improvements fo federal and state public health surveillance systems
  4. The need for an objective and evidence-based report that fully delineates the impacts of regulatory barriers to cannabis research and proposes strategies to support the development of a comprehensive cannabis research agenda

With the recent approval of Epidiolex, which was based on positive results of efficacy from three randomized, double-blind, placebo-controlled trials, we may be seeing a turning point in the world of cannabis policy and research. While the FDA has publicly stated its support for rigorous scientific research on the potential medical uses of cannabis-based or cannabis-derived products, the agency is equally vocal in its commitment to taking action against illegal marketing of cannabis-containing products with unproven medical claims.

[1] The National Academies of Sciences, Engineering and Medicine. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Available at

[2] U.S. Food and Drug Administration. FDA approves first drug comprised of an active ingredient derived from marijuana to treat rare, severe forms of epilepsy. Available at