Regulatory Barriers to Research on Cannabis and Cannabinoids : A Proposed Path Forward, Daniele Piomelli et al., 2019

Regulatory Barriers to Research on Cannabis and Cannabinoids : A Proposed Path Forward

Daniele Piomelli, Robert Solomon, Donald Abrams, Agnes Balla, Igor Grant, Thomas Marcotte, and John Yoder

Cannabis and Cannabinoid Research, Volume 4, Number 1, 2019
Mary Ann Liebert, Inc.

DOI: 10.1089/can.2019.0010


After a century of criminalization, the United States and other industrialized countries are experiencing a dramatic shift in their social and legal attitudes toward cannabis. As of January 2019, 10 states (including California) and the District of Columbia have legalized the plant and its products for both medical and adult recreational use, whereas 24 other states have decriminalized its use as medicine.1 In California, medical cannabis has been legal since 1996 and with the passage of Proposition 64 (the “Adult Use of Marijuana Act”) in November 2016, the regulated use, cultivation, distribution, and sale of cannabis for nonmedical purposes among people over the age of 21 are also allowed. Similarly, a bill to permit and control adult cannabis use was enacted by the Canadian government on October 17, 2018.2

These sweeping transformations are taking place in a context shaped by multiple converging factors:

  • As social and legal perspectives toward cannabis continue to change, its prevalence remains high, especially in vulnerable populations such as pregnant and nursing mothers3;

  • The loosening of state legal restrictions has predictably fueled the emergence of a new cannabis industry, which in the United States is expected to grow at a compound annual rate of 26% per year to reach $21.6 billion in 20214;

  • Despite an increased need for information generated by the legal diffusion of cannabis, our understanding of its genetic and chemical diversity, public health risks, and medical benefits is still critically incomplete;

  • Finally, the legal landscape around the production, sale, and use of cannabis—in fundamental areas such as finances, business structure, regulatory oversight, ethics, antitrust, and more—remains largely undeveloped.

Despite various forms of legalization at the state level, including under California state law, the Drug Enforcement Administration (DEA) maintains a Schedule I classification for cannabis, which defines it as a drug with substantial abuse potential and no accepted medical application. As a result, the use, possession, distribution, and cultivation of cannabis remain illegal under federal law. Research is allowed, but a set of labyrinthine regulations thwarts its progress. Indeed, in its 2017 report on the health impact of cannabis and cannabinoids, the National Academy of Science, Engineering and Medicine (NASEM) of the United States came to the following unequivocal conclusion5:

There are specific regulatory barriers, including the classification of cannabis as a Schedule I substance, that impede the advancement of cannabis and cannabinoid research.

In performing nearly a 10th of the academic research in the United States,6 the University of California (UC) has a responsibility to lead in transmitting knowledge that informs public policy and drives solutions to societal problems. UC conducts cannabis-related research on several of its campuses, but given legalization in many states, which has spurred increased use and availability of cannabis and number of entities involved in cannabis activities, there are compelling reasons for why more research is needed. Universities have an opportunity to be a leader in this area and can contribute to the state and nation through discoveries that improve health, the environment, technology, welfare, and quality of life. Research is fundamentally and indivisibly woven into UC’s mission. UC has a responsibility to lead the world in transmitting advanced knowledge that informs public policy and drives solutions to societal problems. This should also be true for cannabis research, in which California has been at the vanguard with respect to medicinal and adult use. However, the tight restrictions that federal law places on how cannabis research can legally take place present significant challenges in advancing research.

In this article, an interdisciplinary group of medical scientists, plant geneticists, lawyers, and policy experts from the UC system summarizes consensus scientific knowledge about cannabis and its properties, describes the current legal landscape regulating cannabis research, and describes key barriers that hinder its progress. We also highlight some key areas in which basic and clinical research is urgently needed, but cannot be done, and outline a set of policy recommendations to enable future research.