The Role of PD Biomarkers in Biosimilar Development - To Get the Right Answer One Must First Ask the Right Question

Area of Science:

• Biopharmaceutical Development
• Regulatory Science
• Biomarker Research

Background:

• A workshop explored pharmacodynamic (PD) biomarkers for biosimilar development and regulatory approval.
• The discussion considered PD biomarkers potentially replacing Phase III studies.
• However, sponsor motivation, feasibility, and regulatory risks were less explored.

Purpose of the Study:

• To evaluate the role and efficiency of PD biomarkers in biosimilar development.
• To analyze the comparative value of PD biomarkers versus pharmacokinetic (PK) and analytical studies.
• To consider the practical aspects and regulatory implications for biosimilar sponsors.

Main Methods:

• Review of concepts discussed at a US FDA and Duke Margolis workshop.
• Analysis of the established sensitivity of pharmacokinetic (PK) studies for biosimilarity assessment.
• Consideration of the parallel nature of biosimilar development timelines versus originator products.

Main Results:

• Pharmacokinetic (PK) studies and analytical assessments are highly sensitive for detecting differences between biosimilar and reference products.
• These methods already address the core questions of biosimilarity.
• Additional information from PD biomarkers or Phase III studies may offer reassurance but not fundamentally new actionable data.

Conclusions:

• The primary value in biosimilarity assessment lies in analytical and PK studies.
• PD biomarkers and Phase III studies may not be essential for establishing biosimilarity if PK and analytical data are robust.
• Optimizing biosimilar development requires understanding current methodologies and future possibilities, focusing on parallel processing and essential data generation.