United States Pharmacopeia Prepares to Add CBD

The United States Pharmacopeia (USP) is in the process of adding CBD to its list of drugs and their properties, Analytical Cannabis understands.

A work-in-progress chemical profile of CBD, seen by Analytical Cannabis, details the cannabis compound’s properties, such as its typical retention time and the chromatographic procedures used to detect it.

The CBD monograph, as it’s known, was open to public comments until March 31. However, should any viewer wish to submit a late suggestion, it’s understood that the USP does consider comments received after the official comment period has ended.

Cannabis in the pharmacopeia

The USP’s National Formulary is an extensive list of drugs and their methods of detection that is officially recognized by the US federal government.

From aspirin to zinc oxide, the pharmacopeia contains information on thousands of chemical compounds that are used as reference standards for countless labs across the country.

And now CBD is getting added to the list.

A USP document seen by Analytical Cannabis shows a CBD monograph, which details the compound’s identity, strength, purity, and performance, as well as four tests used to validate its presence and properties.

These four tests are listed as:

• Restek’s Raptor ARC-18 brand of HPLC column with L1 packing.
• Waters’ XBridge Shield RP18 brand of column with L1 packing.
• Waters’ XSelect CSH Phenyl-Hexyl brand of column with L11 packing.
• Agilent’s J & W DB-1ms brand of column with G2 phase.

“The Organic Impurities section provides four options for analysis of organic impurities and contaminants based on available information,” Nam-Cheol Kim, scientific liaison at the USP, explained to Analytical Cannabis in an email.

“Each method can resolve the specified impurities in Cannabidiol isolated from Cannabis sativa, and the specified impurities in Cannabidiol obtained by chemical synthesis. Under the proposed monograph, the labeling should state with which procedure the article complies if Procedure 1 is not used.”

The draft monograph also advises that any heavy metals present in CBD should be controlled “according to the principles defined and requirements specified in Elemental Impurities—Limits 〈232〉, as presented in the General Notices 5.60.30.”

Remarking on this requirement, Rob Thomas, a heavy metals expert and principal of the consulting company Scientific Solutions, gave some forewarning. He told Analytical Cannabis the following:

“There are 24 elemental impurities defined in USP Chapter <232> categorized by permitted daily exposure (PDE) limits through the routes of administration – oral, parenteral, inhalation or transdermal. Currently the majority of US states have regulated action limits for Pb [lead], Cd [cadmium], As [arsenic] and Hg [mercury], with some states adding Cr [chromium] and a few other metals.”

“So if a USP-certified CBD product has to meet these limits for all 24 elemental contaminants it would have a profound impact on the cannabis industry,” he continued. “I don’t think there are many CBD producers in the US that would be able to manufacture to these strict specifications.”

It’s currently unknown when the monograph will be formally entered into the US’s official pharmacopeia, but Nam-Cheol Kim told Analytical Cannabis the following:

“USP will follow its standard process for reviewing comments received on the proposed monograph with the Botanical Dietary Supplements and Herbal Medicines Expert Committee. Only after this review can the Expert Committee determine the appropriate next steps, which could potentially include republication in the Pharmacopeial Forum for additional stakeholder feedback on any proposed changes to the monograph. As such, at this time we are unable to provide an anticipated timeline.”