Biosimilar Cost Savings: How They Compare to Original Biologics

Imagine paying for a high-end brand-name product when a version that does the exact same job costs 35% less. In the world of medicine, that's the promise of biosimilars. But here is the catch: unlike a generic aspirin, which is a chemical twin of the original, a biosimilar isn't an identical copy. Because they are made from living cells, they are "highly similar" rather than identical. This biological complexity is exactly why you won't see the 90% price drops we usually associate with generic drugs, yet the savings are still massive enough to change how healthcare systems function.

For anyone managing a chronic condition or an employer overseeing a health plan, understanding biosimilar cost savings is about more than just a cheaper pill. It's about whether a life-changing therapy is actually affordable. While the first FDA-approved biosimilar hit the market in 2015, we are only now seeing the real impact on pricing as the "patent cliffs" of some of the world's most expensive drugs finally crumble.

The Real Price Difference: Biosimilars vs. Originators

When we talk about the "originator," we are referring to the original Biologic is a medication derived from living organisms, such as proteins or antibodies, used to treat complex diseases like rheumatoid arthritis or cancer. Because these drugs are grown in labs using living cells, they are incredibly expensive to produce. When a biosimilar enters the market, it introduces competition, which naturally drags the price down.

In a general sense, biosimilars often provide about 35% savings over the original product when covered under medical benefits. However, the gap can be much wider depending on the specific drug. Take the case of Humira (adalimumab). Once the gold standard for biologics spending, the entry of ten FDA-approved biosimilars by early 2025 led to some options offering up to 85% savings off the list price. Even more striking is Stelara (ustekinumab), where some biosimilar entrants in 2025 were priced as much as 90% lower than the original list price.

Why Biosimilars Aren't as Cheap as Generics

You might wonder why a biosimilar doesn't just cost pennies once the patent expires. The answer lies in the scale of the molecule. Traditional generics are "small-molecule" drugs. They are made via a predictable chemical formula. If you follow the recipe, you get the exact same molecule every time.

Biosimilars, however, are "large-molecule" drugs. They are produced in living cell lines. As industry experts note, the manufacturing and regulatory pathways are far more involved because you are essentially farming a medicine. This means the cost to develop and produce a biosimilar remains high. You can't just "copy-paste" the original; you have to prove to regulators that your version has no clinically meaningful differences in safety, purity, and potency.

Despite these costs, the financial ripple effect is huge. The Association for Accessible Medicines (AAM) reported that biosimilars generated $20.2 billion in savings in 2024 alone. Since 2015, the cumulative savings have reached $56.2 billion. These savings don't just come from the biosimilar's lower price, but also from the pressure they put on the originator to lower their own prices to stay competitive.

The "Rebate Trap" and the Savings Gap

If biosimilars are so much cheaper, why do originators still dominate nearly 99% of spending in some markets? The answer is the "rebate trap." In the US, Pharmacy Benefit Managers (PBMs) act as middlemen. Originator companies often offer these PBMs massive rebates-essentially cash-back deals-to keep their expensive drug as the "preferred" choice on a health plan's list (the formulary).

This creates a weird paradox: the list price of the original drug remains sky-high, but the net price the insurer pays is lowered by the rebate. Because the rebate might be larger than the direct savings offered by a biosimilar, the insurer has a financial incentive to stick with the more expensive original drug. This is why, according to Segal Consulting, the full promise of lower costs hasn't always reached the patient or the plan sponsor.

However, for the patient, the win is more direct. In commercial markets, average out-of-pocket costs for biosimilars have been found to be about 23% lower than their original counterparts. For employees at self-insured companies, switching just one or two biologics to biosimilars can save an organization millions of dollars annually.

The "Biosimilar Void": A Trillion-Dollar Problem

While we've seen success with a few big names, there is a looming problem known as the "biosimilar void." Over the next decade, about 118 biologics are expected to lose their patent protection. That sounds like a goldmine for savings, right? Not quite. Currently, only about 12 of those molecules have biosimilars actually in development.

This means 90% of biologics losing their patents will have no competition waiting in the wings. This is a stark contrast to the European Union, where a much higher percentage of high-sales biologics have biosimilars in the pipeline. If the US can close this gap, there is an estimated $234 billion in unrealized healthcare savings on the table.

To fix this, we need a shift in policy. Some countries, like Norway, have achieved an 86% market share for certain biosimilars within just three years of entry. They do this through aggressive price regulation and policies that practically mandate the use of the most cost-effective version of a drug.

Strategies for Maximizing Savings

If you are a plan sponsor or an employer, you don't have to just accept the status quo. There are specific levers you can pull to ensure you're actually saving money:

• Formulary Positioning: Set your plan so that the biosimilar is the first-choice option, requiring the originator only if the biosimilar doesn't work.
• Step Therapy: Implement protocols where a patient must try a biosimilar before the plan will cover the more expensive original.
• Contract Negotiation: Move away from rebate-heavy contracts and toward those that reward the actual utilization of lower-cost biosimilars.
• Physician Education: Many doctors are hesitant to switch patients because they fear the biosimilar might be less effective. Providing data on clinical equivalence can break this barrier.

These changes aren't overnight. It typically takes 6 to 12 months to fully integrate these strategies into a pharmacy benefit management system, but the payoff is significant. For some employers, switching all employees to a single biosimilar instead of the source biologic can save an average of $1.53 million.