Testing of medicinal cannabis products being supplied via SAS in Australia - content of cannabinoids and presence of delta-8-THC

Background

Medicinal cannabis products are products intended for therapeutic use that contain or are derived from any part of the Cannabis plant. They generally contain the components cannabidiol (CBD) and/or tetrahydrocannabinol (THC) or their corresponding acids.

Medicinal cannabis products are permitted to be supplied into Australia under the Special Access Scheme (SAS), by authorised prescribers (AP), and/or for use in clinical trials. Medicinal cannabis products imported into or supplied in Australia must comply with Therapeutic Goods Order No. 93 (Standard for Medicinal Cannabis) (TGO93). TGA conducts on-going surveillance to monitor the quality of medicinal cannabis products.

A quality concern raised regarding medicinal cannabis products is the adulteration of high tetrahydrocannabinol (THC) products with the synthetically prepared THC isomer delta-8-tetahydrocannabinol (Δ8-THC). While trace amounts of Δ8-THC may be found in the Cannabis sativa plant, delta-9-THC (Δ9-THC) and its corresponding acid are the predominant naturally occurring THC isomers. Large amounts of Δ8-THC can be readily prepared synthetically from cannabidiol (CBD) which is cheap and readily available from hemp. Samples that contain Δ8-THC pose a risk to the community due to the unknown physiological effects as well as residual toxic chemicals from the synthesis. In the USA products containing Δ8-THC are being sold without declaration on the label and the FDA has received several reports of adverse events.[1],[2] It is illegal for medicinal cannabis products supplied in Australia to contain chemically modified cannabinoids such as Δ8-THC.

The survey described in this report was conducted on cannabis oil samples which claim a high level of THC to determine whether medicinal cannabis products available in Australia have been adulterated with Δ8-THC. As part of this survey the products will also be assessed for compliance with the requirements of TGO93 for the stated content of cannabinoids.

A total of 21 medicinal cannabis products were tested by the TGA. The survey targeted higher volume products from Category 4 and 5 (higher THC content). As products were selected to cover as many different suppliers as possible, where a Category 4 or 5 product was not available a Category 3 (balanced content of CBD: THC) was targeted.

Testing

Screening for Δ8-THC by Ultra High Performance Liquid Chromatography (UHPLC)

The samples received were screened for the presence of Δ8-THC using UHPLC. This method has a reporting limit of 0.05 %w/v (0.5 mg/mL) for Δ8-THC.

None of the samples were found to contain a detectable level of Δ8-THC.

Content of cannabinoids by Ultra High Performance Liquid Chromatography (UHPLC)

Each of the samples received were tested for compliance against TGO93, specifically, the stated content of each active ingredient. In particular, Section 12(2) specifies that the average content of each active ingredient in a representative sample of a product must be not less than 90.0 % and not more than 110.0 % of the stated content of that active ingredient. 

An active ingredient for the purposes of TGO93 (whether or not specified) is defined as:

• any THC (together with any corresponding acid) present in the product greater than or equal to 1.0% w/w or w/v
• any other cannabinoid present (together with any corresponding acid) in the product greater than or equal to 2.0% w/w or w/v.

Samples were labelled as containing either THC (together with any corresponding acid), Cannabidiol (CBD) (together with any corresponding acid), a combination of both, or in one instance a combination of THC, CBD and Cannabinol (CBN). 

The samples were tested for content of total CBD, total THC and/or CBN and were reported as a percentage of the stated label claim. Where samples contained any corresponding THC and CBD acids, the content of the acid was calculated as the equivalent base (either THC or CBD) and included in the calculation of total CBD and THC % contents. 

Details of the results obtained are included in Appendix A.

An assessment of all samples was made for the presence of any other cannabinoids present in a concentration greater or equal to 2% w/w or w/v. None of the samples were found to contain other cannabinoids at a level that would constitute an active ingredient. 

Of the 21 samples that were received for testing, one sample failed to meet the TGO93 requirements for content of the active ingredient. The sample failed to meet the lower limit requirement for total THC. 

The sample of T25 Ruby THC Oil - 30mL (THC 25mg/mL), supplied by Cannatrek Medical Pty Ltd, returned a low result of 84.6% of label claim for total THC. The requirements for content of cannabinoids, for oil finished products, are 90.0-110.0% of label claim. 

It is well known that the content of active ingredients of medicinal cannabis decline with time, as such the reported results only represent the content measured at the time of analysis. Medicinal cannabis products must meet the requirements of TGO93 for the duration of their nominated shelf lives.

The supplier of the product failing to meet the requirements was notified of the testing result and requested to quarantine all remaining stock. The sponsor quarantined all remaining stock at the time of being notified and with the batch no longer within expiry the matter has been resolved to the satisfaction of the TGA.

The remaining 20 products tested met the requirements for the content of active ingredients.

Appendix A: Details and results of samples analysed