The randomized, double-blind controlled studies that became standard in the 1950s for drug clinical trials are not well suited for multi-compound natural products because having more than one bioactive phytocompound exponentially increases the variables that need to be controlled. In fact, the FDA has only approved several herbal prescription drugs and none involve hemp or cannabis.
The sole FDA approved cannabis plant-derived drug is a single, isolated and purified cannabinoid, CBD, in the drug called Epidiolex made by GW Pharmaceuticals that was approved in June 2018. The other FDA approved cannabinoid type drug is also a single molecule, a synthesized form of THC, marketed under the international generic name, Dronabinol.
The consistency of botanicals and plant extracts pose a challenge for the standard clinical trial protocol as potencies as well as the ratios of the bioactive compounds can vary.
The simple question that is difficult to answer is knowing which compound or combination of compounds in what proportions in a plant extract is effective as medicine.
Therapeutic effects become even more complex to understand because everybody is different. “One size fits all” does not apply in herbal medicine. Even with common drugs, some people find relief with ibuprofen while other folks use acetaminophen. Some people use one for headaches and the other for muscle aches. Is the natural sleep aid, melatonin, effective for you? It is an OTC drug in the US but a prescription drug in other countries – go figure! Does Benadryl knock you out or perk you up?
Each person reacts differently to treatment, whether it is with a FDA approved drug or a plant-based remedy. Cannabinoids and the other compounds in hemp act uniquely on a person’s endocannabinoid system, like a lock is specific to a key. Accordingly, the well recognized entourage effect of the various phytochemicals in the hemp plant is obviously a challenge for the FDA.
Another complexity the FDA has to address with all medicines is that clinical trials are not real world conditions. And most health problems don’t tend to be a single malady that can be alleviated by a single molecule.
The clinical trial process does work but has limitations. Even when a single molecule is approved for a single indication like pain, the FDA process is not fail-safe as with the case of opioids that were approved to be safe and effective based on parameters thought to be prudent but have led to widespread addiction.
The good news is that the FDA is committed to sorting out how to allow consumers access to hemp-derived and other plant based medicines.
Dietary supplements are regulated under the FDA’s DSHEA regulations established about 25 years ago. Food and cosmetics have their own regulatory framework. Both are different than the clinical trial framework for what the FDA defines as drugs. Another FDA pathway for approval of ingredients is named GRAS (Generally Regarded As Safe).
Coming back to hemp-derived bioactive phytochemicals like CBD, CBN, CBG, CBC, terpenes, terpenoids, and polyphenols that are non-addictive, non-toxic and non-psychotropic (i.e., non-intoxicating), in theory, GRAS surely would be the simplest pathway out of the maze we are in.
At some point, all of the regulatory confusion (or at least most) will be sorted out and even more people will be able to benefit from the hemp plant after almost 100 years of marginalization and illegal status.