ABSTRACT
Introduction: Coronavirus Disease 2019 (COVID-19) causes a wide range of symptoms, including death. As persons recover, some continue to experience symptoms described as Post-Acute COVID-19 Syndrome (PACS). The objectives of this study were to measure the efficacy of Formula C™, a cannabidiol (CBD)-rich, whole-flower terpene-rich preparation in managing PACS symptoms. Materials and Methods: This randomized, placebo-controlled, single-blind, open-label crossover study was conducted in 2021. Informed consent was obtained from participants, and they were randomized to two treatment groups. Group 1 (n=15) received blinded active product for 28 days, and Group 2 (n=16) received blinded placebo for 28 days (Treatment Period 1). Both groups crossed over to open-label active product for 28 days (Treatment Period 2) with a safety assessment at day 70. Patient-Reported Outcomes Measurement Information System (PROMIS®) scores and the Patient Global Impression of Change (PGIC) score were used to assess primary and secondary objectives. Safety assessments were also done at each visit. Results: Twenty-four participants completed study, with 8 withdrawals, none related to study product. PGIC and PROMIS scores improved across both groups at day 28. This raised questions about the placebo. A reanalysis of the placebo confirmed absence of CBD and unexpected medical concentration of terpenes. The study continued despite no longer having a true placebo. The improved scores on outcome measures were maintained across the open label treatment period. There were no safety events reported throughout the study. Discussion: For persons with PACS who are nonresponsive to conventional therapies, this study demonstrated symptom improvement for participants utilizing Formula C. In addition, the benefits seen in Group 2 suggest the possibility that non-CBD formulations rich in antioxidants, omega-3, and omega-6 fatty acids, gamma-linoleic acid, and terpenes may also have contributed to the overall improvement of the partial active group through the study. Conclusion: Given that both groups demonstrated improvement, both formulations may be contributing to these findings. Limitations include the small number of participants, the lack of a true placebo, and limited time on study products. Additional studies are warranted to explore both CBD-rich hemp products and hempseed oil as treatment options for PACS. Trial Registration ClinicalTrials.gov Identifier: NCT04828668.