Health Canada Consolidates Guidance on Comparative Bioavailability Standards
| Posted: 22 May 2012
By Alexander Gaffney
Health Canada released new, consolidated guidance regarding how sponsors should conduct and analyze comparative bioavailability studies used to support applications for generic medications.
The 22 May guidance consolidates eleven existing guidance and notice to industry documents, which Health Canada explains will be superseded by the new guidance once it comes into effect.
Bioavailability studies are used to show a product’s equivalency to a Health Canada-approved reference product. Health Canada requires such product to be within 80% and 125% of both the mean maximum concentration (Cmax) and the relative mean area under the concentration versus time curve (AUCT) to be found bioequivalent to the reference product.
Health Canada adds that, generally, these studies should be conducted using subjects in a “fasted state” unless there are safety concerns associated with using the product without food. Modified-release drugs, however, must be tested in both fasted and fed conditions to account for an increased risk of variability between products.
The consolidated guidance also explains a number of different scenarios, including testing drugs with serious toxicity concerns, testing drugs with a half-life of more than 24 hours, drugs with delayed rates of absorption, drugs with critical dosing concerns, testing combination products, testing highly variable drugs, and more.
Health Canada - Guidance Document - Comparative Bioavailability Standards: Formulations Used for Systemic Effects