Compromised External Validity: Federally Produced Cannabis Does Not Reflect Legal Markets

Abstract

As the most widely used illicit drug worldwide, and as a source of numerous under-studied pharmacologically-active compounds, a precise understanding of variability in psychological and physiological effects of Cannabis varieties is essential. The National Institute on Drug Abuse (NIDA) is designated as the sole legal producer of Cannabis for use in US research studies. We sought to compare the chemical profiles of Cannabis varieties that are available to consumers in states that have state-legalized use versus what is available to researchers interested in studying the plant and its effects. Our results demonstrate that the federally-produced Cannabis has significantly less variety and lower concentrations of cannabinoids than are observed in state-legal U.S. dispensaries. Most dramatically, NIDA’s varieties contain only 27% of the THC levels and as much as 11–23 times the Cannabinol (CBN) content compared to what is available in the state-legal markets. Research restricted to using the current range of federally-produced Cannabis thus may yield limited insights into the chemical, biological and pharmacological properties, and medical potential of material that is available in the state markets. Investigation is urgently needed on the full diversity of Cannabis chemotypes known to be available to the public.

Research grade marijuana supplied by the National Institute on Drug Abuse is genetically divergent from commercially availableCannabis

“…Our results clearly demonstrate that NIDA Cannabis samples are substantially different from most commercially available drug-type strains, sharing a genetic affinity with hemp samples in most analyses. Previous research has found that medical and recreational Cannabis from California, Colorado, and Washington differs significantly in cannabinoid levels from the research grade marijuana supplied by NIDA 14 Our genetic investigation adds to this previous research, indicating that the genetic makeup of NIDA Cannabis is also distinctive from commercially available medical and recreational Cannabis .…”

“…This finding reveals that research conducted with NIDA Cannabis may not be indicative of the effects that consumers are experiencing. Additionally, research has demonstrated that Cannabis distributed by NIDA has lower levels of the principal medicinal cannabinoids (THC and CBD) and higher levels of degradation byproducts of cannabinoids (cannabinol, CBN) 14 Taken together, these results demonstrate the need for there to be greater diversity of Cannabis available for medical research and that the genetic provenance of those samples to be established to fully understand the implications of results.…”

“…Hemp-type Cannabis tends to have higher concentrations of CBD than drug-types 13 . Drug-type Cannabis usually contains > 12% THC and averages ~ 10-23% THC in commercially available dispensaries 14–16 . Within the two major usage groups, Cannabis can be further divided into varietals, which are referred to as strains.…”

“…Recent research has documented that NIDA-provided Cannabis has distinctly different cannabinoid profiles than commercially available Cannabis 14 Specifically, Vergara et al (2017) found that NIDA samples contained only 27% of the amount of THC and 48% of CBD levels of commercially available Cannabis . The substantial chemical differences between NIDA and commercially available Cannabis raises significant questions about whether research conducted with federal Cannabis is indicative of the experience consumers are having.…”

“…The chemical makeup of each variant of Cannabis is influenced by the genetic makeup as well as environmental conditions. Given that previous research has determined the cannabinoid levels of research grade marijuana from NIDA is significantly different from commercially available Cannabis 14 , genetic investigations are warranted to determine if NIDA Cannabis is genetical distinct from other sources. In the current study we investigated the genetic relationship of NIDA provided Cannabis to commercially available drug-type strains, as well as feral and cultivated hemp.…”