Equal THC Doses, Different Plasma Profiles: A Human Formulation Trial
Two oral products containing the same THC dose can produce different plasma concentration profiles. A randomized human trial comparing a delivery formulation with a medium-chain triglyceride oil comparator demonstrates why labeled milligrams alone do not fully describe systemic exposure.
A controlled formulation comparison
The trial randomized 32 healthy adults in a triple-blind, parallel-group design. Each preparation delivered 10 mg THC and approximately 10 mg CBD. The investigators collected serial samples for 48 hours and measured cannabinoids and metabolites in plasma.
One preparation used the Solutech delivery system; the comparator used MCT oil. This was a comparison between groups, rather than a crossover in which each participant received both formulations. Randomization strengthens the formulation comparison, but it does not eliminate all variability in a small sample.
Peak exposure and timing changed
The Solutech preparation produced higher maximum concentrations and a faster time to peak than the comparator for the measured cannabinoid profiles described by the authors. Such findings show that the vehicle carrying a dose can matter to absorption and the resulting concentration-time curve.
They do not establish superior therapeutic benefit or a numerical increase in driving impairment. Those outcomes were not validated by measuring plasma pharmacokinetics. Plasma concentrations also should not be directly substituted for whole-blood results without an appropriate, independently supported basis.
Why the limitations matter in a case
The investigation used a single dose. Cannabis-use histories varied substantially, and sleep–wake patterns were not controlled. Participants left the clinic after the initial observation period and returned for later samples. The authors acknowledged that 48 hours might be insufficient to characterize the full terminal elimination phase.
The study was funded by New Age Ventures, and the first author disclosed being its CEO. That interest should accompany interpretation of a commercially relevant formulation comparison.
For exposure reconstruction, the practical lesson is to identify the actual product and formulation before borrowing a concentration curve from another preparation. Our rat carrier comparison concerns a separate animal experiment; it should remain distinct from this human evidence and cannot provide a human dosing conversion.
Primary research
A Randomized, Triple-Blind, Comparator-Controlled Parallel Study Investigating the Pharmacokinetics of Cannabidiol and Tetrahydrocannabinol in a Novel Delivery System, Solutech, in Association with Cannabis Use History. DOI: 10.1089/can.2021.0176.
