When a life-saving biologic drug loses its patent, it doesn’t just open the door for cheaper versions-it reshapes entire healthcare systems. The next five years will see more than $200 billion in annual biologic sales come under pressure from biosimilars, and the ripple effects are already being felt in hospitals, pharmacies, and patient wallets. This isn’t about generic pills. These are complex, living medicines-protein-based therapies that treat cancer, autoimmune diseases, and rare conditions. And unlike generics, which are chemically identical copies, biosimilars are highly similar but not identical. They require years of testing, billions in investment, and careful regulatory navigation. The next wave of patent expirations is here, and the stakes couldn’t be higher.
What Makes a Biosimilar Different From a Generic?
Most people think of generics as simple copies of brand-name drugs. Aspirin, metformin, or lisinopril? Those are small-molecule drugs with simple chemical structures. You can replicate them exactly. Biosimilars? They’re made from living cells-yeast, bacteria, or mammalian cells engineered to produce proteins like antibodies. Think of it like cloning a human face: you can get very close, but tiny differences in folding, sugar attachments (glycosylation), or protein shape can change how the drug works in the body.
Take Keytruda (pembrolizumab, a monoclonal antibody used in cancer immunotherapy). Its reference product has over 237 patents protecting it, including ones on manufacturing processes and specific glycosylation patterns. A biosimilar must match these exactly to be approved. That’s why it took over a decade to develop, and why the first biosimilars won’t hit the U.S. market until 2028. Compare that to a generic like Ibrance (palbociclib, a small-molecule cancer drug), which became available in 2024 after a single chemical synthesis change. Biosimilars aren’t just cheaper copies-they’re scientific feats.
Which Biologics Are Losing Protection Between 2025 and 2030?
The next five years will be the biggest wave of biosimilar entries ever. Here are the top five blockbusters set to lose patent protection:
- Eylea (aflibercept) - Expiration in 2025. Used for macular degeneration. With $5.9 billion in U.S. sales in 2023, it’s already seeing biosimilar competition. Three biosimilars-Yesafili, Opuviz, and Enzeevu-were approved in 2024. Market share hit 12% in Q1 2025.
- Humira (adalimumab) - Expiration in 2023. The former top-selling drug in history. After a nine-year delay due to patent litigation, 12 biosimilars are now on the market. They captured 80% of new prescriptions within 18 months. This is the blueprint for what’s coming next.
- Enbrel (etanercept) - Expiration in 2029. Sandoz’s biosimilar launched in 2023 at a 35% discount. Already used in over 68% of new prescriptions at major hospital systems like Mass General Brigham.
- Keytruda (pembrolizumab) - Expiration in 2028. Projected to generate $25.5 billion in 2024. Fourteen companies are in Phase 3 trials. This will be the largest biosimilar entry in history-worth more than all other upcoming biosimilars combined.
- Cosentyx (secukinumab) - Expiration in 2029. A psoriasis and arthritis drug. Samsung Bioepis’ biosimilar received positive review from the European Medicines Agency in October 2025, with a 2026 EU launch expected.
These aren’t just drugs. They’re revenue engines. Merck, Bristol Myers Squibb, and Regeneron are now racing to protect their market share-not just with patents, but with rebates, patient assistance programs, and even authorized biosimilars (like Regeneron’s $1.2 billion deal with Alvotech).
How Are Biosimilars Priced? What’s the Real Savings?
Biosimilars don’t slash prices the way generics do. A generic might cost 90% less. Biosimilars? They typically launch at 15-35% below the reference product. Why? Because the development cost is 10-20 times higher than a generic. A single biosimilar can cost $150-250 million to bring to market, with 7-10 years of R&D.
But here’s the twist: even 20% savings add up fast. The RAND Corporation estimates biosimilars could save the U.S. healthcare system $250 billion over the next decade. In 2024, the global biosimilars market hit $12.7 billion-up 28% from 2023-and is projected to hit $80 billion by 2030. That’s not just savings-it’s systemic change.
Some payers are pushing hard. Cigna’s 2025 Medicare Advantage plans offer $0 copays for biosimilars versus $50 for the brand. Centene Corporation now requires biosimilars for all new patients on tumor necrosis factor inhibitors. Hospitals like Kaiser Permanente updated their EHRs to auto-substitute biosimilars for filgrastim products. But not all systems are ready. Medicare Part B pays providers based on the Average Sales Price (ASP), meaning they earn more if they use the expensive brand. That’s why it often takes 18 months after approval for a biosimilar to gain real traction.
Why Are Some Biosimilars Delayed? Patent Thickets and Legal Battles
It’s not just science. It’s law. Originator companies build “patent thickets”-hundreds of overlapping patents on manufacturing, delivery, and even storage. Humira had 237 patents, and litigation delayed biosimilar entry for nine years. The FDA’s Purple Book (a public database listing approved biologics and their patent status) is now updated daily, and a January 2025 rule requires real-time patent listing. This should reduce delays.
But settlements still happen. The Eliquis (apixaban) litigation delayed generic competition by four years. Dr. Janet Woodcock, former FDA Acting Commissioner, called these settlements a “dangerous precedent.” Meanwhile, companies like Pfizer and Novartis are forming joint ventures-Viatris, created by Pfizer and Mylan-is now a biosimilar powerhouse. The strategy? Partner with biosimilar developers to control the market instead of fighting it.
Regional Differences: Europe vs. U.S. Adoption
The U.S. and Europe are playing different games. The European Medicines Agency has approved 82 biosimilars. In some countries, over 70% of patients on biologics use biosimilars. Why? Simple: reimbursement rules favor cost savings. In the U.S., the system is fragmented. Pharmacy benefit managers (PBMs), insurers, and hospitals all have different incentives. Rebates often go to PBMs, not patients. So even if a biosimilar is cheaper, it doesn’t always reach the patient.
But change is coming. The FDA approved 17 biosimilars in 2024-up from just five in 2020. The number of active biosimilar candidates jumped 300% since 2020, with 412 in development targeting 87 reference products. The gap is closing. In 2025, the FDA released new guidance on “Analytical Similarity for Highly Complex Biologics,” making it easier to approve next-gen biosimilars for antibody-drug conjugates. This isn’t just about cost-it’s about access.
Real-World Impact: What Do Patients and Doctors Say?
At the American Society of Clinical Oncology in 2024, Dr. Laura Chow reported “excellent real-world equivalence” between Humira and its biosimilars in inflammatory bowel disease. But Dr. Richard Pazdur from the FDA’s Oncology Center noted some patients had unexpected immune reactions when switching between rituximab biosimilars and the original. That’s the tension: for most, biosimilars work fine. For a small group, the difference matters.
Patient surveys tell a mixed story. The Cancer Support Community found 78% of 1,243 respondents were satisfied with cost savings. But 34% were confused about whether they could be switched without consent. Specialty pharmacists at CVS Caremark saw a 22% drop in prior authorization denials for biosimilars in Q2 2025-meaning fewer hoops to jump through. But academic centers still struggle to track long-term outcomes across multiple biosimilar versions. One hospital system in Boston told us: “We can’t tell if a patient got biosimilar A or B because our EHR doesn’t track it.”
What’s Next? The Battle for 2028 and Beyond
The real test is Keytruda in 2028. With $25.5 billion in annual sales, it’s the crown jewel. If biosimilars capture even 50% of that market, it could cut Medicare Part B spending by $12 billion a year, according to Dr. Henry Waxman. But Merck isn’t giving up. They’re launching their own authorized biosimilar, partnering with a third party to control pricing and distribution. Other companies are rushing to file. Coherus BioSciences and Biocon Biologics are in late-stage trials.
Meanwhile, the next wave is already forming. Drugs like Tysabri, Stelara, and Dupixent are on the horizon. And with the FDA streamlining approvals and payers demanding savings, biosimilars won’t just be an option-they’ll become the default.
The future isn’t just about cheaper drugs. It’s about smarter systems. Better tracking. Transparent pricing. And real patient choice. The patent cliff isn’t a threat-it’s an opportunity. To make biologics accessible. To cut waste. To save lives. And to finally fix a system that’s been too expensive for too long.
Are biosimilars safe?
Yes. The FDA requires biosimilars to show no clinically meaningful differences in safety, purity, and potency compared to the reference product. This involves thousands of lab tests, animal studies, and clinical trials. Over 47 biosimilars are approved in the U.S., with no safety signal different from the original drugs. But for complex biologics like those used in cancer, some patients may respond differently-especially if switched mid-treatment. Always consult your doctor before switching.
Why are biosimilars cheaper than biologics but not as cheap as generics?
Biosimilars are made from living cells, requiring complex manufacturing, strict quality controls, and years of testing. A single biosimilar can cost $150-250 million to develop. Generics are simple chemical copies that cost a fraction to produce. Biosimilars aren’t meant to be 90% cheaper-they’re meant to be 15-35% cheaper, which still saves billions across the healthcare system.
Can I be switched to a biosimilar without my doctor’s approval?
In most U.S. states, pharmacists can substitute an interchangeable biosimilar without notifying the prescriber-similar to how generics work. But for non-interchangeable biosimilars, the prescriber must specify “do not substitute.” Only 12 biosimilars are currently designated as interchangeable by the FDA. Always check your prescription and ask your pharmacist if substitution is allowed.
Do insurance companies push biosimilars?
Yes. Many insurers now require biosimilars as the first choice for new patients. Cigna offers $0 copays for biosimilars. Centene mandates biosimilar use for TNF inhibitors. Medicare Part B still pays more for brand-name drugs due to its reimbursement model, but that’s changing as payers pressure providers to adopt cost-saving alternatives.
Will biosimilars replace all biologics eventually?
Not all. Some biologics have complex mechanisms that make biosimilars harder to develop-like antibody-drug conjugates or multi-target therapies. Also, originator companies are developing next-generation biologics with improved features (longer duration, fewer side effects) that won’t have biosimilar equivalents. But for established drugs like Humira, Keytruda, and Eylea, biosimilars will dominate. Expect 60-70% market share within 24 months of entry for most products.
What Should Patients and Providers Do Now?
If you’re on a biologic: don’t panic. Your current treatment won’t disappear overnight. But start asking questions. Ask your doctor: “Is there a biosimilar for my drug?” Ask your pharmacist: “Is this biosimilar interchangeable?” Ask your insurer: “Do I get a lower copay if I switch?”
If you’re a provider: update your EHR to track biosimilar use. Know which of your patients are on drugs with upcoming biosimilar competition. Prepare for patient questions. Educate your team on substitution rules. And don’t assume biosimilars are “lesser”-they’re rigorously tested and often the best financial choice for patients.
The biologics revolution isn’t coming. It’s already here. And it’s changing how medicine is delivered-one biosimilar at a time.
Leon Hallal
March 10, 2026 AT 02:21Biosimilars are just a way for big pharma to keep making money while pretending to lower costs.