Biosimilars, regulatory flexibility and why CMC data matters more than ever

Biosimilars have become one of the most powerful levers for improving global access to biologic therapies¹. As healthcare systems face mounting cost pressures, biosimilars offer a scientifically rigorous pathway to broaden availability without compromising quality or performance^1,2. At the same time, regulatory thinking around biosimilar development has evolved—reflecting a deeper understanding of what truly establishes biosimilarity.

Across major agencies, there is growing recognition that biosimilarity is fundamentally a chemistry, manufacturing and controls (CMC) driven determination^2,3. While clinical data still plays a role, the centre of gravity has shifted. Regulatory flexibility is expanding around the extent of clinical evidence required, while high quality analytical characterization has become the foundation of regulatory confidence.

The regulatory landscape: then and now

Early biosimilar frameworks closely mirrored traditional biologics development. Large comparative clinical efficacy trials were viewed as the primary demonstration of similarity compared to the reference product, often adding time, cost and complexity without proportionate scientific value^2,3.

Today, regulators including the Food and Drug Administration (FDA), European Medicines Agency (EMA), World Health Organization (WHO), Medicines and Healthcare products Regulatory Agency (MHRA), Health Canada etc., apply risk based, stepwise and totality of evidence approaches. These frameworks place analytical similarity and CMC data at the forefront, with clinical studies designed to address any remaining uncertainty rather than serve as the main proof point.

Several factors have driven this shift. More than two decades of global biosimilar experience has produced a strong safety record. Analytical technologies have advanced dramatically, allowing deeper insight into molecular structure, post-translational modifications, functional activity, and purity. Real world evidence has reinforced that approved biosimilars perform consistently across indications and populations⁴.

Flexibility does not mean lower standards

Regulatory flexibility reflects scientific efficiency—not reduced rigor. Agencies remain uncompromising on expectations for quality, safety and performance. What has changed is how those expectations are met.

In many programs, robust analytical comparability with the innovator or reference product  combined with well designed pharmacokinetic and pharmacodynamic data has supported the waiver of large comparative efficacy trials^2,5. In other cases, immunogenicity datasets have been streamlined when analytical and functional evidence demonstrated minimal residual uncertainty. Indication extrapolation has become more common where mechanism of action, receptor engagement, and functional assays align across indications.

These decisions are grounded in science, not shortcuts.

Why CMC sits at the centre of biosimilarity

Biosimilars must demonstrate a high degree of structural and functional similarity to their reference products. This assessment is rooted in CMC data, including analytical characterization, bioassays, stability profiles, and manufacturing controls.

Modern analytical tools provide unprecedented clarity. High resolution mass spectrometry enables detailed evaluation of glycosylation patterns, charge variants, and other critical attributes. Orthogonal methods confirm consistency across multiple dimensions, increasing confidence in similarity.

Manufacturing itself is inseparable from product quality. Because biologics are inherently variable, controlling the process—from cell line development through formulation and container closure—is central to maintaining biosimilarity over time. Concerns about process drift underscore why comparability is not a one‑time exercise but a lifecycle commitment⁶.

When CMC packages are comprehensive and well justified, regulators frequently conclude that residual uncertainty is low. In these cases, clinical studies serve a confirmatory role rather than an exploratory one.

Building a high quality CMC dossier

Strong biosimilar submissions share several common elements:

• Analytical similarity exercises covering primary through higher order structure and functional activity tied to the mechanism of action
• Clear definition of critical quality attributes, with acceptance ranges informed by reference product variability
• Well controlled manufacturing processes, including cell line, purification strategy and formulation design
• Robust stability and stress testing data to characterize degradation pathways
• Lifecycle planning, with ongoing comparability strategies and post approval commitments aligned to CMC risk

Speeding access through science led development

Reduced clinical burden can translate into faster development timelines and lower costs, while increasing alignment across global regulatory agencies supports more efficient multinational submissions. Ultimately, these efficiencies benefit healthcare systems and patients through greater affordability, broader access, and sustainable competition.

Looking ahead

Biosimilar regulation continues to move toward greater reliance on advanced analytics and manufacturing science. As confidence in CMC driven assessments grows, clinical waivers may become the default when analytical evidence is conclusive. Continued international convergence and emerging manufacturing technologies are likely to reinforce this trajectory.

For biosimilar developers, the message is clear: investing early and deeply in CMC excellence is not optional—it is central to navigating an increasingly science led regulatory environment and accelerating access to high quality biologic therapies.

Get in touchwith our consulting team to discuss your product pipeline and how to navigate the regulatory landscape for biosimilars.

References

1. World Health Organization. Biosimilars: Expanding access to essential biologic therapies. Biosimilars: Expanding access to essential biologic therapies (Last updated February 2025, last accessed March 2026)
2. European Medicines Agency. Reflection paper on a tailored clinical approach in biosimilar development. Reflection paper on a tailored clinical approach in biosimilar development (Last updated April 2025, last accessed March 2026)
3. U.S. Food and Drug Administration. Scientific considerations in demonstrating biosimilarity to a reference product: Guidance for industry. https://www.fda.gov/media/82647/download (Last updated April 2015, last accessed March 2026)
4. Simoens, S., Lockhart, C. M., & Courmier, D. F. (2025). What role for real-world evidence in market access of biosimilars? Frontiers in Pharmacology, 16, Article 1538866.
5. U.S. Food and Drug Administration. Scientific considerations in demonstrating biosimilarity to a reference product: Updated recommendations for assessing the need for comparative efficacy studies; Draft guidance for industry. https://www.federalregister.gov/documents/2025/11/20/2025-20380/scientific-considerations-in-demonstrating-biosimilarity-to-a-reference-product-updates (Last updated November 2025, last accessed March 2026)
6. U.S. Food and Drug Administration. Comparability protocols for post approval changes to the chemistry, manufacturing, and controls information in an NDA, ANDA, or BLA: Guidance for industry. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/comparability-protocols-postapproval-changes-chemistry-manufacturing-and-controls-information-nda (Last updated October 2022, last accessed March 2026)