The FDA has made modest changes to its guidance on clinical pharmacology testing for biosimilars.
The guidance finalizes a draft version published in May 2014 that detailed the pharmacokinetic (PK) and pharmacodynamic (PD) data needed to show biosimilarity. The final guidance expands on the previous version by providing additional details on: the assessment of PD biomarkers; the integrity of bioanalytical methods in PK and PD studies; the development of PK and PD data; and the populations for PK and PD studies.
When determining which PD biomarkers to use to measure the response of a biosimilar, the FDA advised sponsors to consider the time it takes to return to baseline with the discontinuation of dosing. They should also consider the PD biomarker’s analytical validity.