Biologic medicines have transformed the way we treat cancer, autoimmune diseases, rare conditions, and chronic illnesses. But these medicines have always come with a significant challenge: their cost. Biosimilar drugs are changing that equation worldwide.

In 2024, the FDA approved 19 biosimilars in a single year, the highest number ever recorded by any regulatory body globally. Both the FDA and EMA are now working to cut biosimilar development timelines from five to eight years down to two to four years. These are not small changes — they signal a fundamental shift in how the world accesses some of its most critical medicines.

For hospitals, healthcare institutions, clinical research organisations, and pharmaceutical procurement teams, understanding biosimilar drugs is now essential knowledge. This article explains what biosimilar drugs are, how they are developed, where they are used, and what the global access landscape looks like today.

What Is a Biosimilar Drug?

A biosimilar drug is a biological medicine that is highly similar to an already approved reference biologic, known as the originator or reference product. It has the same mechanism of action, the same target, and no clinically meaningful differences in safety, purity, or potency.

To understand biosimilars, it helps to first understand biological medicines. Unlike conventional drugs that are made through chemical synthesis and are structurally identical from batch to batch, biologics are large, complex molecules produced in living systems such as bacteria, yeast, or mammalian cells. This includes proteins, antibodies, and enzymes. Because they come from living systems, no two batches are perfectly identical — not even two batches of the same originator product.

A biosimilar is not a generic drug. A generic drug is a chemically synthesised small molecule that is structurally identical to its reference. A biosimilar is a large, complex biological molecule that is highly similar but, by the nature of biological production, cannot be an exact copy. The biosimilarity standard exists to define and regulate what "highly similar" means in clinical and scientific terms.

Biosimilars exist because of patents. When the patent protecting an originator biologic expires, other manufacturers are legally permitted to develop and seek approval for highly similar versions. In the European Union, biosimilar competition has driven price reductions of up to 80 percent on some originator biologics. In the United States, biologics account for just 5 percent of prescriptions but 51 percent of total drug spending. Biosimilars are the most powerful tool available to address this imbalance.

How Are Biosimilar Drugs Developed?

Biosimilar development is a rigorous scientific process. It is substantially more complex than generic drug development and requires a stepwise comparability exercise covering analytical, pharmacokinetic, and clinical dimensions.

Step 1: Analytical and Structural Characterisation

Development begins with a detailed molecular comparison of the biosimilar candidate and the reference biologic. Developers use advanced analytical techniques to characterise molecular structure, purity, potency, biological activity, glycosylation (sugar chain) profiles, and immunogenicity risk. This analytical work is now the most critical phase of biosimilar development. Both the FDA and EMA have confirmed that strong analytical and pharmacokinetic data can replace the need for large comparative clinical efficacy trials in many cases.

Step 2: Pharmacokinetic and Pharmacodynamic Studies

Pharmacokinetic (PK) studies measure how the medicine behaves in the human body, including absorption, distribution, metabolism, and elimination. Pharmacodynamic (PD) studies assess the biological effect of the medicine at the cellular or molecular level. Demonstrating PK and PD similarity is a key requirement before regulatory submission.

Step 3: Clinical Safety and Immunogenicity Assessment

Biosimilar developers must demonstrate that the biosimilar does not produce immune system responses that are clinically meaningfully different from those of the reference biologic. Immunogenicity assessment is critical because even minor structural differences can affect how the immune system responds to a biological medicine.

Step 4: Regulatory Submission and Approval

Following the full comparability exercise, an Abbreviated Biologics Licence Application (aBLA) is submitted to the FDA, a Marketing Authorisation Application (MAA) is submitted to the EMA, or an equivalent submission is made to the relevant national regulatory authority. The regulator reviews the totality of the analytical, PK, PD, and clinical evidence before granting approval.

Biosimilar vs. Generic Drug: Key Differences

Understanding the distinction between biosimilars and generics is important for procurement teams, clinicians, and institutional buyers.

Characteristic	Generic Drug	Biosimilar Drug
Source	Chemical synthesis	Living biological systems
Structure	Identical to reference	Highly similar, not identical
Complexity	Small molecule	Large, complex protein or antibody
Approval Standard	Bioequivalence	Biosimilarity (analytical + clinical)
Development Cost	Approx. USD 1 to 5 million	Approx. USD 100 to 300 million
Development Timeline	2 to 4 years	5 to 8 years (trending shorter)

Therapeutic Applications of Biosimilar Drugs

Biosimilars are approved across a broad and growing range of therapeutic areas. Their role is expanding rapidly as patents on major biologic medicines expire.

Oncology

Biosimilars have made a significant impact in cancer treatment by reducing the cost of therapies that were previously accessible only to patients in high-income healthcare systems. Key approved oncology biosimilars include trastuzumab biosimilars for HER2-positive breast cancer, bevacizumab biosimilars for colorectal and lung cancers, rituximab biosimilars for non-Hodgkin lymphoma, and pertuzumab biosimilars for HER2-positive metastatic breast cancer. In November 2025, the FDA approved the first interchangeable pertuzumab biosimilar, expanding access to this important HER2-targeted combination therapy.

Autoimmune and Inflammatory Conditions

The autoimmune biosimilar market is one of the largest and most established globally. Following the patent expiry of adalimumab (Humira), one of the world's best-selling biologics, multiple biosimilars entered the market and significantly reduced treatment costs for rheumatoid arthritis, Crohn's disease, ulcerative colitis, psoriasis, and ankylosing spondylitis. Infliximab and etanercept biosimilars have also been widely adopted across these indications.

Neurology

In November 2025, the first biosimilar of natalizumab was approved by the FDA for relapsing multiple sclerosis and Crohn's disease. This represented a significant milestone for neurological biosimilar development and patient access.

Endocrinology and Metabolic Disorders

Insulin biosimilars have improved diabetes care access globally, particularly in low and middle income countries. In February 2025, the FDA approved a new insulin aspart biosimilar as an affordable alternative for diabetes management. Growth hormone biosimilars, approved in Europe as far back as 2006, have broadened access for patients with growth disorders.

Bone Health

Denosumab biosimilars for osteoporosis and bone cancer related conditions saw a major expansion in 2025. Multiple FDA approvals across the year have created significant pricing competition, giving patients and healthcare systems access to these important therapies at substantially reduced cost.

Haematology

Erythropoietin (EPO) biosimilars have been used in Europe for nearly two decades to manage anaemia in oncology and renal disease patients. Filgrastim biosimilars have reduced the cost of managing chemotherapy-induced neutropenia worldwide.

Global Regulatory Landscape in 2025 and 2026

The regulatory environment for biosimilars is evolving at an unprecedented pace. The most significant reforms in biosimilar policy since the first European approval in 2006 are now underway.

FDA: United States

The FDA established its biosimilar approval pathway in 2010 through the Biologics Price Competition and Innovation Act. Since then, the agency has approved more than 76 biosimilars. In October 2025, major proposed reforms were announced that would eliminate mandatory comparative clinical efficacy studies and streamline the interchangeability designation process. The FDA's stated goal is to halve biosimilar development timelines and significantly reduce costs, making more affordable biosimilars accessible to American patients faster.

EMA: European Union

Europe has led global biosimilar adoption since the EMA approved its first biosimilar in 2006 and has accumulated nearly two decades of real world data confirming the safety of biosimilar use, including for patients who switch between a biologic and a biosimilar. In April 2025, the EMA issued draft guidance proposing that structural, functional, and pharmacokinetic data may be sufficient to demonstrate biosimilarity, potentially eliminating the need for large clinical efficacy studies. Implementation is expected in 2026.

MHRA: United Kingdom

Post-Brexit, the MHRA has established its own independent biosimilar approval pathway while maintaining close alignment with global standards. The NHS has been an active early adopter of biosimilar medicines. When the Humira patent expired in 2018, the NHS prioritised biosimilar adoption, generating what NHS leadership described at the time as the largest savings from a single drug negotiation in NHS history.

India: CDSCO

India's Central Drugs Standard Control Organisation has established biosimilar guidelines under the New Drugs and Clinical Trials Rules. India is both a major global biosimilar manufacturer and a growing biosimilar market. Indian biosimilar manufacturers supply products to regulated markets worldwide under internationally recognised quality standards.

The Role of a Pharmaceutical Supplier in Biosimilar Access

For hospitals, clinical institutions, and procurement teams sourcing biosimilar medicines internationally, working with a compliant and experienced pharmaceutical supplier is essential. Biosimilars, like their reference biologics, come with specific supply requirements.

• Cold chain supply: most biosimilars require temperature controlled storage and transportation at 2 to 8 degrees Celsius or below, maintained throughout the entire supply chain.
• Batch documentation: certificates of analysis, manufacturer credentials, and full regulatory compliance records must accompany every shipment.
• Regulatory import authorisation: country-specific requirements, pharmacovigilance obligations, and distribution compliance must be managed for each destination market.
• Named patient or managed access supply: for biosimilars approved in one market but not yet available in another, structured access pathways such as named patient supply and managed access programmes are required.

Conclusion

Biosimilar drugs represent one of the most important opportunities in global pharmaceutical access. By combining the clinical power of biologic medicine with the economic benefits of market competition, biosimilars are making critical treatments available to more patients across more healthcare systems than ever before.

The regulatory reforms now underway at the FDA and EMA will accelerate this process further. More biosimilars will reach the market faster, at lower development cost, and with streamlined approval processes. The therapeutic pipeline is expanding across oncology, immunology, rare disease, neurology, and metabolic disorders.

For healthcare institutions and procurement teams navigating international biosimilar access, working with a compliant pharmaceutical supplier ensures that temperature controlled supply chains, regulatory documentation, and import authorisation requirements are managed with the precision and accountability that biosimilar medicines demand. Contact GNH India to discuss biosimilar or biologic medicine supply for your institution.