For 25 years, cannabis policy discussion has evolved regarding medical cannabis use. Recent consideration of regulating non-medical cannabis use has begun to move from a prohibitionist model to a more controlled system of access. What does this mean for research?

There exists now, on an international scale, a variety of medical and non-medical cannabis policy options, and this gives rise to what is essentially a global social experiment. Given this unique landscape, it is pertinent to consider what the research community can do to maximize the likelihood that lessons learned can feed back into policy development to ensure that decisions are made based on best available evidence. However, appeals for more research without addressing some fundamental barriers to research are meaningless. Transition to a public health model of cannabis regulation allows for correction of these institutional factors.

One major (and often politically charged) hurdle is access to cannabis materials (Frood, 2009). Restrictions on drug scheduling and supply lead to a paucity of standardized cannabis products, with sufficient quality for regulatory approval for research, and in formulations that are of relevance to lived experience. A variety of cannabinoid levels, as well as other ingredients, in herbal and extracted forms, with a range of delivery system options, are needed. Access to a range of cannabis strains is needed: due to the complex pharmacology of cannabis and the varying levels of its constituents (including cannabinoids, terpenes, and flavonoids) across different strains, generalization of the effects of one strain to another may be complicated as effects seen with one trial may be unique to the specific chemical properties of that strain. While this may appear to be of most relevance to therapeutic applications, the increasing use of a variety of cannabis products for non-medical use demands that we learn more about these products and their properties to inform consumers and policy makers alike.

Research on cannabis also demands important methodological innovations. Cannabis is a complex botanical substance and defies reduction to single agent pharmacology. Considerations of credible placebos and candidates for active control groups are needed for clinical trials. Studies that estimate and control for the effects of expectations are needed (cannabis perceptions range from risk of severe harm to anticipation of cure) (Chabrol et al, 2006; Stark-Adamec et al, 1981). Cannabis-specific screening tools, and outcome measures to measure and standardize cannabis use and associated behaviors, are needed to enable comparisons between studies and over time. In the short term, emphasis on the randomized controlled trial as the ‘gold standard’ may need to be revisited with consideration given to pragmatic observational and ‘real world’ study designs (Frieden, 2017). In a world of self-report and experience, the importance of case reports, narrative and qualitative research and registries becomes poignant (Bottorff et al, 2013; Wade, 2015).

No discussion of research challenges is complete without consideration of funding, but this is also complex. Drug, device, and product development is typically the purview of industry (pharmaceutical as well as commercial), but here barriers pertaining to intellectual property and health claims (as well as access issues mentioned above) lead to limitations in investment in the standard drug development pathway and commercialization. Research on new cannabinoid drugs, devices, and technologies (eg DNA sequencing, extraction, isolation) and data capture (eg registries, ‘big data’) need to be supported along with investments in laboratory testing methods, standards, and capacity.

A changing global cannabis policy environment is therefore a unique opportunity to address research challenges with novel and robust approaches to deliver meaningful and relevant data.

Funding and disclosure

The author receives grants to his institution from CanniMed and Green Sky Labs, and is a consultant to Canopy Health Innovations, CannaRoyalty, and Zynerba.