Chemistry and Pharmacology of Delta-8-Tetrahydrocannabinol.

Cannabis sativa is one of the oldest plants utilized by humans for both economic and medical purposes. Although the use of cannabis started millennia ago in the Eastern hemisphere, its use has moved and flourished in the Western nations in more recent centuries. C. sativa is the source of psychoactive cannabinoids that are consumed as recreational drugs worldwide. The C21 aromatic hydrocarbons are restricted in their natural occurrence to cannabis (with a few exceptions). Delta-9-tetrahydrocannabinol (Δ9-THC) is the main psychoactive component in cannabis, with many pharmacological effects and various approved medical applications. However, a wide range of side effects are associated with the use of Δ9-THC, limiting its medical use. In 1966, another psychoactive cannabinoid, Delta-8-tetrahydrocannabinol (Δ8-THC) was isolated from marijuana grown in Maryland but in very low yield. Δ8-THC is gaining increased popularity due to its better stability and easier synthetic manufacturing procedures compared to Δ9-THC. The passing of the U.S. Farm Bill in 2018 led to an increase in the sale of Δ8-THC in the United States. The marketed products contain Δ8-THC from synthetic sources. In this review, methods of extraction, purification, and structure elucidation of Δ8-THC will be presented. The issue of whether Δ8-THC is a natural compound or an artifact will be discussed, and the different strategies for its chemical synthesis will be presented. Δ8-THC of synthetic origin is expected to contain some impurities due to residual amounts of starting materials and reagents, as well as side products of the reactions. The various methods of analysis and detection of impurities present in the marketed products will be discussed. The pharmacological effects of Δ8-THC, including its interaction with CB1 and CB2 cannabinoid receptors in comparison with Δ9-THC, will be reviewed.

Chemistry and Biological Activities of Cannflavins of the Cannabis Plant.

Background: Throughout history, Cannabis has had a significant influence on human life as one of the earliest plants cultivated by humans. The plant was a source of fibers used by the oldest known civilizations. Cannabis was also used medicinally in China, India, and ancient Egypt. Delta-9-tetrahydrocannabinol (Δ9-THC), the main psychoactive compound in the plant was identified in 1964 followed by more than 125 cannabinoids. More than 30 flavonoids were isolated from the plant including the characteristic flavonoids called cannflavins, which are prenylated or geranylated flavones. Material and Methods: In this review, the methods of extraction, isolation, identification, biosynthesis, chemical synthesis, analysis and pharmacological activity of these flavonoids are described. Results: The biosynthetic routes of the cannflavins from phenylalanine and malonyl CoA as well as the microbial biotransformation are also discussed. Details of the chemical synthesis are illustrated as an alternative to the isolation from the plant materials along with other possible sources of obtaining cannflavins. Detailed methods discussing the analysis of flavonoids in cannabis are presented, including the techniques used for separation and detection. Finally, the various biological activities of cannflavins are reviewed along with the available molecular docking studies. Conclusion: Despite the low level of cannflavins in cannabis hamper their development as naturally derived products, efforts need to be put in place to develop high yield synthetic or biosynthetic protocols for their production in order for their development as pharmaceutical products.

THC degradation does not impair the accuracy of THC doses aerosolized by the metered-dose SyqeAir inhaler: a 24-month stability trial.

BACKGROUND: Although the worldwide use of medical cannabis (MC) is on the rise, there is insufficient data regarding the long-term stability of phytocannabinoids in the plant material under different storage conditions. Specifically, there is insufficient data on the effect of storage conditions on the availability of (-)-∆9-trans-tetrahydrocannabinol (THC) in vaporized cannabis. The Syqe inhaler delivers metered doses of phytocannabinoids by inhalation and utilizes accurate quantities of ground cannabis inflorescence packaged in tamper-proof cartridges. We aimed to assess the stability of phytocannabinoids in ground cannabis before and after packaging in Syqe cartridges as well as the reproducibility of THC delivery in the aerosolized dose. METHODS: Ground MC inflorescence was stored under different temperature and humidity conditions, before or after being packaged in Syqe cartridges. Concentrations of the major phytocannabinoids therein were analyzed at different time points using ultra-high performance liquid chromatography (U-HPLC). THC doses aerosolized via the Syqe inhaler were evaluated using cartridges stored for up to 2 years at 25°C. Every vapor chip contains 13.5±0.9 mg of ground MC powder. RESULTS: No significant changes were observed in phytocannabinoid concentrations in ground cannabis inflorescence after 3 months of bulk storage in a polypropylene container and sealed in an aluminum foil pouch at 5°C. In contrast, significant changes in phytocannabinoid concentrations were found when ground inflorescence was stored in the cartridges at 25°C for 2 years. Specifically, CBGA, THCA, and total THC concentrations decreased from 0.097±0.023, 2.7±0.3, and 2.80±0.16 mg/chip at baseline to 0.044±0.007 (55% decrease), 1.50±0.27 (44% decrease), and 2.20±0.083 (21% decrease) mg/chip following 2 years, respectively, while CBN and THC concentrations increased from 0.005±0.005 and 0.44±0.11 mg/chip at baseline to 0.14±0.006 (2700% increase) and 0.88±0.22 (100% increase) mg/chip following 2 years, respectively. Storage at 30°C revealed a steeper change in phytocannabinoid concentrations within an even shorter period. Despite the significant change of relative cannabinoid composition within the cartridge, the actual THC dose present in the aerosol remained relatively stable throughout this period and within the dosage range of 500mcg±25% required for pharmaceutical-grade inhalers. CONCLUSIONS: MC powder in Syqe cartridges may be stored at room temperature for at least 2 years after production without affecting the aerosolized THC dose delivered to patients by more than ±25%. Future studies should analyze additional phytocannabinoids and terpenes in the cannabis inflorescence and assess the stability of different cannabis cultivars following storage in Syqe cartridges.

Developing Robust Standardised Analytical Procedures for Cannabinoid Quantification: Laying the Foundations for an Emerging Cannabis-Based Pharmaceutical Industry.

The plant genus Cannabis is a prolific producer of unique pharmaceutically relevant metabolites, commonly referred to as cannabinoids. Robust and standardised methods for the quantification of cannabinoids within botanical and drug forms is a critical step forward for an emerging Cannabis-based pharmaceutical industry, which is poised for rapid expansion. Despite a growing body of analytical methods for the quantification of cannabinoids, few have been validated using internationally accredited guidelines. Moreover, standardised methods have yet to be developed for application at various stages of manufacture as well as for different levels of processing and refinement. Validation parameters for establishing robust standardised methods for cannabinoid quantification within Cannabis-based drug forms are critically discussed. Determining an appropriate level of specificity (discrimination) among heterogeneous botanical matrices as well as evaluating accuracy (recovery) and inter-laboratory precision (reproducibility) within strict and volatile regulatory environments are potential obstacles to the establishment of robust analytical procedures. We argue that while some of these challenges remain unique to Cannabis, others are common to botanical-based drug development and manufacture. In order to address potential barriers to analytical method standardisation, a collaborative research initiative inclusive of academic and commercial stakeholders is proposed.

The Trouble with CBD Oil.

In just a few years, cannabidiol (CBD) has become immensely popular around the world. After initially being discovered as an effective self-medication for Dravet syndrome in children, CBD is now sold and used to treat a wide range of medical conditions and lifestyle diseases. The cannabinoid CBD, a non-psychoactive isomer of the more infamous tetrahydrocannabinol (THC), is available in a growing number of administration modes, but the most commonly known is CBD oil. There are currently dozens, if not hundreds, of producers and sellers of CBD oils active in the market, and their number is increasing rapidly. Those involved vary from individuals who prepare oils on a small scale for family and (Facebook) friends to compounding pharmacies, pharmaceutical companies, and licensed cannabis producers. Despite the growing availability of CBD, many uncertainties remain about the legality, quality, and safety of this new "miracle cure." As a result, CBD is under scrutiny on many levels, ranging from national health organizations and agricultural lobbyists to the WHO and FDA. The central question is whether CBD is simply a food supplement, an investigational new medicine, or even a narcotic. This overview paper looks into the known risks and issues related to the composition of CBD products, and makes recommendations for better regulatory control based on accurate labeling and more scientifically supported health claims. The intention of this paper is to create a better understanding of the benefits versus the risks of the current way CBD products are produced, used, and advertised.

Evaluating the Effects of Gamma-Irradiation for Decontamination of Medicinal Cannabis.

In several countries with a National medicinal cannabis program, pharmaceutical regulations specify that herbal cannabis products must adhere to strict safety standards regarding microbial contamination. Treatment by gamma irradiation currently seems the only method available to meet these requirements. We evaluated the effects of irradiation treatment of four different cannabis varieties covering different chemical compositions. Samples were compared before and after standard gamma-irradiation treatment by performing quantitative UPLC analysis of major cannabinoids, as well as qualitative GC analysis of full cannabinoid and terpene profiles. In addition, water content and microscopic appearance of the cannabis flowers was evaluated. This study found that treatment did not cause changes in the content of THC and CBD, generally considered as the most important therapeutically active components of medicinal cannabis. Likewise, the water content and the microscopic structure of the dried cannabis flowers were not altered by standard irradiation protocol in the cannabis varieties studied. The effect of gamma-irradiation was limited to a reduction of some terpenes present in the cannabis, but keeping the terpene profile qualitatively the same. Based on the results presented in this report, gamma irradiation of herbal cannabis remains the recommended method of decontamination, at least until other more generally accepted methods have been developed and validated.

Dose-dependent effects of cannabis on the neural correlates of error monitoring in frequent cannabis users.

Cannabis has been suggested to impair the capacity to recognize discrepancies between expected and executed actions. However, there is a lack of conclusive evidence regarding the acute impact of cannabis on the neural correlates of error monitoring. In order to contribute to the available knowledge, we used a randomized, double-blind, between-groups design to investigate the impact of administration of a low (5.5 mg THC) or high (22 mg THC) dose of vaporized cannabis vs. placebo on the amplitudes of the error-related negativity (ERN) and error positivity (Pe) in the context of the Flanker task, in a group of frequent cannabis users (required to use cannabis minimally 4 times a week, for at least 2 years). Subjects in the high dose group (n=18) demonstrated a significantly diminished ERN in comparison to the placebo condition (n=19), whereas a reduced Pe amplitude was observed in both the high and low dose (n=18) conditions, as compared to placebo. The results suggest that a high dose of cannabis may affect the neural correlates of both the conscious (late), as well as the initial automatic processes involved in error monitoring, while a low dose of cannabis might impact only the conscious (late) processing of errors.

Cannabis and creativity: highly potent cannabis impairs divergent thinking in regular cannabis users.

RATIONALE: Cannabis users often claim that cannabis has the potential to enhance their creativity. Research suggests that aspects of creative performance might be improved when intoxicated with cannabis; however, the evidence is not conclusive. OBJECTIVE: The aim of this study was to investigate the acute effects of cannabis on creativity. METHODS: We examined the effects of administering a low (5.5 mg delta-9-tetrahydrocannabinol [THC]) or high (22 mg THC) dose of vaporized cannabis vs. placebo on creativity tasks tapping into divergent (Alternate Uses Task) and convergent (Remote Associates Task) thinking, in a population of regular cannabis users. The study used a randomized, double-blind, between-groups design. RESULTS: Participants in the high-dose group (n = 18) displayed significantly worse performance on the divergent thinking task, compared to individuals in both the low-dose (n = 18) and placebo (n = 18) groups. CONCLUSIONS: The findings suggest that cannabis with low potency does not have any impact on creativity, while highly potent cannabis actually impairs divergent thinking.

A protocol for the delivery of cannabidiol (CBD) and combined CBD and ∆9-tetrahydrocannabinol (THC) by vaporisation.

BACKGROUND: Significant interest has emerged in the therapeutic and interactive effects of different cannabinoids. Cannabidiol (CBD) has been shown to have anxiolytic and antipsychotic effects with high doses administered orally. We report a series of studies conducted to determine the vaporisation efficiency of high doses of CBD, alone and in combination with ∆9-tetrahydrocannabinol (THC), to achieve faster onset effects in experimental and clinical trials and emulate smoked cannabis. METHODS: Purified THC and CBD (40 mg/ml and 100 mg/ml respectively) were loaded onto a liquid absorbing pad in a Volcano vaporiser, vaporised and the vapours quantitatively analysed. Preliminary studies determined 200 mg CBD to be the highest dose effectively vaporised at 230 ° C, yielding an availability of approximately 40% in the vapour phase. Six confirmatory studies examined the quantity of each compound delivered when 200 mg or 4 mg CBD was loaded together with 8 mg of THC. RESULTS: THC showed 55% availability when vaporised alone or with low dose CBD, while large variation in the availability of high dose CBD impacted upon the availability of THC when co-administered, with each compound affecting the vaporisation efficiency of the other in a dynamic and dose-dependent manner. We describe optimised protocols that enable delivery of 160 mg CBD through vaporisation. CONCLUSIONS: While THC administration by vaporisation is increasingly adopted in experimental studies, often with oral predosing with CBD to examine interactive effects, no studies to date have reported the administration of CBD by vaporisation. We report the detailed methodology aimed at optimising the efficiency of delivery of therapeutic doses of CBD, alone and in combination with THC, by vaporisation. These protocols provide a technical advance that may inform methodology for clinical trials in humans, especially for examining interactions between THC and CBD and for therapeutic applications of CBD. TRIAL REGISTRATION: Current Controlled Trials ISRCTN24109245.

The medicinal use of cannabis and cannabinoids--an international cross-sectional survey on administration forms.

Cannabinoids, including tetrahydrocannabinol and cannabidiol, are the most important active constituents of the cannabis plant. Over recent years, cannabinoid-based medicines (CBMs) have become increasingly available to patients in many countries, both as pharmaceutical products and as herbal cannabis (marijuana). While there seems to be a demand for multiple cannabinoid-based therapeutic products, specifically for symptomatic amelioration in chronic diseases, therapeutic effects of different CBMs have only been directly compared in a few clinical studies. The survey presented here was performed by the International Association for Cannabinoid Medicines (IACM), and is meant to contribute to the understanding of cannabinoid-based medicine by asking patients who used cannabis or cannabinoids detailed questions about their experiences with different methods of intake. The survey was completed by 953 participants from 31 countries, making this the largest international survey on a wide variety of users of cannabinoid-based medicine performed so far. In general, herbal non-pharmaceutical CBMs received higher appreciation scores by participants than pharmaceutical products containing cannabinoids. However, the number of patients who reported experience with pharmaceutical products was low, limiting conclusions on preferences. Nevertheless, the reported data may be useful for further development of safe and effective medications based on cannabis and single cannabinoids.

The prevalence and incidence of medicinal cannabis on prescription in The Netherlands.

BACKGROUND: A growing number of countries are providing pharmaceutical grade cannabis to chronically ill patients. However, little published data is known about the extent of medicinal cannabis use and the characteristics of patients using cannabis on doctor's prescription. This study describes a retrospective database study of The Netherlands. METHODS: Complete dispensing histories were obtained of all patients with at least one medicinal cannabis prescription gathered at pharmacies in The Netherlands in the period 2003-2010. Data revealed prevalence and incidence of use of prescription cannabis as well as characteristics of patients using different cannabis varieties. RESULTS: Five thousand five hundred forty patients were identified. After an initial incidence of about 6/100,000 inhabitants/year in 2003 and 2004, the incidence remained stable at 3/100,000/year in 2005-2010. The prevalence rate ranged from 5 to 8 per 100,000 inhabitants. Virtually all patients used some form of prescription medication in the 6 months preceding start of cannabis use, most particularly psycholeptics (45.5 %), analgesics (44.3 %), anti-ulcer agents (35.9 %) and NSAIDs (30.7 %). We found no significant association between use of medication of common indications for cannabis (pain, HIV/AIDS, cancer, nausea, glaucoma) and variety of cannabis used. CONCLUSIONS: This is the first nationwide study into the extent of prescription of medicinal cannabis. Although the cannabis varieties studied are believed to possess different therapeutic effects based on their different content of tetrahydrocannabinol (THC) and cannabidiol (CBD), no differences in choice of variety was found associated with indication.

Metabolic fingerprinting of Cannabis sativa L., cannabinoids and terpenoids for chemotaxonomic and drug standardization purposes.

Cannabis sativa L. is an important medicinal plant. In order to develop cannabis plant material as a medicinal product quality control and clear chemotaxonomic discrimination between varieties is a necessity. Therefore in this study 11 cannabis varieties were grown under the same environmental conditions. Chemical analysis of cannabis plant material used a gas chromatography flame ionization detection method that was validated for quantitative analysis of cannabis monoterpenoids, sesquiterpenoids, and cannabinoids. Quantitative data was analyzed using principal component analysis to determine which compounds are most important in discriminating cannabis varieties. In total 36 compounds were identified and quantified in the 11 varieties. Using principal component analysis each cannabis variety could be chemically discriminated. This methodology is useful for both chemotaxonomic discrimination of cannabis varieties and quality control of plant material.

A qualitative and quantitative HPTLC densitometry method for the analysis of cannabinoids in Cannabis sativa L.

INTRODUCTION: Cannabis and cannabinoid based medicines are currently under serious investigation for legitimate development as medicinal agents, necessitating new low-cost, high-throughput analytical methods for quality control. OBJECTIVE: The goal of this study was to develop and validate, according to ICH guidelines, a simple rapid HPTLC method for the quantification of Delta(9)-tetrahydrocannabinol (Delta(9)-THC) and qualitative analysis of other main neutral cannabinoids found in cannabis. METHODOLOGY: The method was developed and validated with the use of pure cannabinoid reference standards and two medicinal cannabis cultivars. Accuracy was determined by comparing results obtained from the HTPLC method with those obtained from a validated HPLC method. RESULTS: Delta(9)-THC gives linear calibration curves in the range of 50-500 ng at 206 nm with a linear regression of y = 11.858x + 125.99 and r(2) = 0.9968. CONCLUSION: Results have shown that the HPTLC method is reproducible and accurate for the quantification of Delta(9)-THC in cannabis. The method is also useful for the qualitative screening of the main neutral cannabinoids found in cannabis cultivars.

Delta-9-tetrahydrocannabinol accumulation, metabolism and cell-type-specific adverse effects in aggregating brain cell cultures.

Despite the widespread use of Cannabis as recreational drug or as medicine, little is known about its toxicity. The accumulation, metabolism and toxicity of THC were analyzed 10 days after a single treatment, and after repeated exposures during 10 days. Mixed-cell aggregate cultures of fetal rat telencephalon were used as in vitro model, as well as aggregates enriched either in neurons or in glial cells. It was found that THC accumulated preferentially in neurons, and that glia-neuron interactions decreased THC accumulation. The quantification of 11-OH-THC and of THC-COOH showed that brain aggregates were capable of THC metabolism. No cell-type difference was found for the metabolite 11-OH-THC, whereas the THC-COOH content was higher in mixed-cell cultures. No cell death was found at THC concentrations of 2 microM in single treatment and of 1 microM and 2 microM in repeated treatments. Neurons, and particularly GABAergic neurons, were most sensitive to THC. Only the GABAergic marker was affected after the single treatment, whereas the GABAergic, cholinergic and astrocytic markers were decreased after the repeated treatments. JWH 015, a CB2 receptor agonist, showed effects similar to THC, whereas ACEA, a CB1 receptor agonist, had no effect. The expression of the cytokine IL-6 was upregulated 48 h after the single treatment with 5 microM of THC or JWH 015, whereas the expression of TNF-alpha remained unchanged. These results suggest that the adverse effects of THC were related either to THC accumulation or to cannabinoid receptor activation and associated with IL-6 upregulation.

Cannabis tea revisited: a systematic evaluation of the cannabinoid composition of cannabis tea.

Cannabis is one of the oldest known medicinal plants, and a large variety of biological activities have been described. The main constituents, the cannabinoids, are thought to be most important for these activities. Although smoking of cannabis is by far the most common way of consumption, a significant part of medicinal users consume it in the form of a tea. However, not much is known about the composition of cannabis tea, or the effect of different parameters during preparation, handling or storage. In this study we used the high-grade cannabis available in Dutch pharmacies to study the cannabinoid composition of tea under standardized and quantitative conditions. Experimental conditions were systematically varied in order to mimic the possible variations made by medicinal users. During analysis there was a specific focus on the cannabinoid tetrahydrocannabinol and its acidic precursor, tetrahydrocannabinolic acid. Also the role of non-psychoactive cannabinoids as components of cannabis tea are discussed. The results obtained in this study provide a clear quantitative insight in the phytochemistry of cannabis tea preparation and can contribute to a better appreciation of this mode of cannabis administration.

Synthesis and spectroscopic characterization of cannabinolic acid.

Cannabinoids, the main constituents of the cannabis plant, are being increasingly studied for their medicinal properties. Cannabinolic acid (CBNA; 1) was synthesized from tetrahydrocannabinolic acid (THCA; 2), a major constituent of the cannabis plant, by aromatization using selenium dioxide mixed with trimethylsilyl polyphosphate as catalyst in chloroform. Purification was achieved by centrifugal partition chromatography, and the final product had a purity of over 96% by GC analysis. Spectroscopic data on CBNA such as 1H-NMR and IR, and molar extinction coefficients, as well as chromatographic data are presented as useful references for further research on CBNA. The developed method allows production of CBNA on a preparative scale, making it available for further studies on its biological activities as well as use as a reference standard for analytical procedures.

Structure elucidation of the tetrahydrocannabinol complex with randomly methylated beta-cyclodextrin.

The low aqueous solubility of the bioactive cannabinoid tetrahydrocannabinol (THC) is a serious obstacle for the development of more efficient administration forms. In this study the aqueous solubility of THC was tested in the presence of alpha-, beta- and gamma-CD, and randomly methylated beta-CD (RAMEB). It was found that only RAMEB was able to increase the aqueous solubility of THC to a significant level. A THC concentration of about 14 mg/ml was reached by using a 24% (187 mM) RAMEB solution, which means an increase in solubility of four orders of magnitude. The resulting THC/RAMEB complex was investigated through phase-solubility analysis, complemented by (1)H NMR, NOESY- and UV-studies in order to obtain details on the stoichiometry, geometry and thermodynamics of the complexation. The binding ratio of THC to CD was found to be 2:1, with the second THC molecule bound by non-inclusion interactions. Based on the obtained results a model for the complex structure is presented. Stability of the complex under laboratory room conditions was tested up to 8 weeks. Results show that complexation with RAMEB seems to be promising for the development of water-based THC formulations.