The Difficulty of Assessing Similarity of Extracts and other Botanical Preparations in a Regulatory Regime

Since the coming into force of the Canadian Natural Health Product regulations in 2004, the scientific staff at the Natural Health Products Directorate (NHPD) have had to evaluate claims for a variety of botanical preparations including isolates, extracts, decoctions and tinctures. The regulations require that applicants for market authorizations provide evidence for the safety and efficacy of each medicinal ingredient, however for low risk products, this evidence may be in the form of published scientific articles rather than formulation specific evidence. Challenges have therefore occurred when comparing the characterization of the product proposed for marketing with that described in the literature. Descriptions of extracts in the literature are usually incomplete and frequently refer to proprietary information that is unavailable to both the applicant and the regulator. Applicants are often importers or consultants and are not provided with data that accurately characterizes the botanical preparations. Knowledge about the biological activity of phytochemicals in extracts and whole herbs is largely unknown, although the body of evidence on common botanicals is growing. Since information about the bioavailability of botanicals and the factors that influence activity is sparse, this overall lack of data makes authorizing claims in the current environment a challenging task. This presentation will highlight common issues that arise during evaluation of data and how the NHPD is tackling these issues.