Canopy Growth’s Worm Study Finds CBD Is Safe for Long-Term Use

A new study from Spectrum Therapeutics, the medical division of Canadian cannabis company Canopy Growth, suggests that lifelong CBD use is not only safe, it might also lengthen average lifespan and increase activity levels in old age.

The study, which looked at the toxicity and lifespan effects of CBD in the nematode worm species Caenorhabditis elegans, claims to be the first piece of research to examine CBD’s long term effects in an in vivo model and calls for other mammalian studies in the future to investigate the same.

CBD provides a boost to animals in old age

By using worms with a lifespan of only two-to-three weeks, the Canopy Growth scientists were able to study the effects of CBD use over an entire animal lifetime. Although the invertebrate isn’t exactly a human counterpart, the researchers cite that between 60-to-80 percent of the species’ genes have some sort of human analog, and the worms’ digestive, reproductive, endocrine, sensory, and neuromuscular systems are good model systems for human health conditions.

Acute toxicity trials found no evidence of increased mortality at any of the doses tested; the most notable adverse effect was a 30 percent drop-off in movement at the highest dose given – a dose that the researchers say is “at least 10 times outside of physiologically relevant concentrations.”

In the lifelong exposure studies, which used more relevant dosage amounts, there were no ill-effects seen in mortality. No changes were seen in terms of maximum lifespan. Although long-term CBD use did appear to extend the average lifespan of the animals by up to 18.3 percent, and late-stage life activity by over 200 percent. Even at dosages equivalent to a low or moderate dose in humans, the long-term use of CBD was able to effectively attenuate age-related declines in activity.

“As they aged, they moved more like young animals,” Hunter Land, senior director of translational and discovery science at Canopy Growth, explained to Bloomberg. “Rather than seeing something toxic, we see the opposite – it actually increases health parameters.”

Private research left to forge the path for future regulations

While it might seem slightly outlandish to look at a study done on nematode worms and immediately start making comparisons to human CBD use, it is something that is necessitated by the huge explosion in popularity that CBD has enjoyed over the past several years.

In order to come up with regulations to guide the safe use of the cannabinoid and its inclusion in other products, there has to be solid empirical evidence for regulator to use as a basis for their decisions. With millions around the world already using CBD products, these kinds of safety data need to be generated quickly, and companies taking up the mantle with studies on animals with shorter lifespans is a part of the industry’s swift response to the demand for hard science.

“Despite widespread use of CBD, no life-long toxicity studies had been conducted to date to determine the impact – or potential impact – of long-term exposure to CBD,” Land commented in a press statement. “These results serve as the only CBD life-long exposure data in an in vivo model to date, and the absence of long-term toxicity gives us the evidence we need as an industry to continue researching the potential health benefits for the broader application of CBD.”

The US Food and Drug Administration (FDA) is currently engaged in the process of drawing up guidance for the industry on CBD use, having presented draft enforcement guidance to the White House Office of Management and Budget (OMB) earlier this summer. This guidance is still currently pending review.

Last week the FDA Office of Women’s Health hosted a virtual public meeting on the topic of “sex and gender differences in [CBD] use and responses.” The federal agency said that the cannabinoid’s varying effects on men and women is likely to influence its regulation, but it has yet to lay out exactly how.

Who are Canopy Growth?

Based in Smith Falls, Ontario, Canopy Growth, the parent company behind Spectrum Therapeutics, is one of the largest and most well-known cannabis companies in the world. In 2014, the firm made history by becoming the first publicly traded cannabis company in North America. As of 2018, it became the first cannabis company to be listed on the New York Stock Exchange.

But more recently, the company has fallen on tougher times. In March of this year, Canopy Growth shut down two greenhouses and laid off around 500 staff as part of a restructuring move. Around the same time, other big names in cannabis, including Aurora Cannabis, Tilray Inc., and MedMen Enterprises, were making similar decisions as the market as a whole failed to meet high financial expectations amid the slow roll-out of cannabis retail facilities in new cannabis markets.

While many have raised concerns about the sizeable number of industry players now funding cannabis research, the current federal prohibition of cannabis has made it materially more difficult for universities and similar institutions to conduct independent research of their own. But without more research, it becomes impossible for federal agencies to make evidence-based decisions when implementing new policy.

Many university researchers fear that researching a federally prohibited substance could put their federal funding in jeopardy. But, on the other hand, accepting industry funding could one day give rise to a conflict of interest. While academic institutions grapple with these tough decisions, private companies with research and development arms are now coming in to fill the gap.

“I don’t think I’ve ever spoken to a university administrator who doesn’t have anxiety over federal funding,” Michael McDonell, an associate professor at Washington State University, told Cannabis Wire in May. “We’re struggling because unlike any other agricultural commodity we cannot get funding from USDA or from private donors. Our hands are tied from the private-donors side in a lot of ways because we can’t take any money from the industry.”