Same Drug Class, 4x the Price: Biosimilar Costs All Over the Map

The Rise of Biosimilars

Specialty drugs have transformed pharmaceutical spending over the past decade; some of these medications cost hundreds of thousands of dollars annually.  In 2023, the FDA began approving biosimilars for adalimumab (Humira), one of the world's best-selling drugs.  Unlike traditional generics, biosimilars are highly similar but not identical copies of biologics, offering the potential for significant cost savings while maintaining clinical effectiveness.

Humira biosimilars launched with 80-85% discounts and FDA approval for automatic pharmacy substitution. We wanted to know: did those savings actually reach employers? The answer: not always.  

We analyzed 2024 prescription data from more than 950 self-funded employers. Our data reveals significant cost variations. For self-funded employers, knowing which biosimilar their plan offers can mean thousands of dollars per prescription in savings or losses.

Key Findings

1. Prices for different biosimilars vary by more than 4x: The same class of medications ranges from $639 (Yusimry) to $2,655 (Amjevita) per prescription across our book of business, a $2,016 difference.

2. Costs differ dramatically across states: The weighted average cost for adalimumab prescriptions varies from $8,387 in Washington DC (highest) to $2,306 in Michigan (lowest), a $6K gap between our clients in these states.

3. High capture rates don't guarantee low costs: For our clients in Vermont, biosimilar prescriptions grew by more than double Humira's decline (226% capture rate). Yet Vermont's average cost remains high at $6,182 per script, while Michigan achieves both strong capture (76%) and low costs ($2,317).

The $2,000 Spread: Biosimilar Price Ranges

Not all biosimilars cost the same. The average price per script across our client data reveals a wide range of price points:  

• Yusimry: $639 per script (91% less than Humira)

• Hadlima: $929 per script (86% less than Humira)

• Hyrimoz: $1,455 per script (79% less than Humira)

• Amjevita: $2,655 per script (55% less than Humira)

The price differential between the lowest and highest cost biosimilars reaches $2,016 per prescription.

Biosimilar Capture Rates and Cost Impact

According to our employer data, biosimilar capture rates vary significantly across our book of business, from 34% capture in Arkansas to 226% in Vermont; but our data shows that capture rates don't predict costs. In 2024:

• Arkansas: For every 100 Humira prescriptions lost, only 34 biosimilar prescriptions appeared (34% capture rate)

• Michigan: For every 100 Humira prescriptions lost, 76 biosimilar prescriptions appeared (76% capture rate)

• Vermont: 226 biosimilar prescriptions appeared for every 100 Humira prescriptions lost (226% capture rate - which indicates that some new patients started directly on biosimilars)

However, more biosimilar prescriptions don't automatically mean lower costs. Our clients in Vermont show high biosimilar market capture with a weighted average price of $6,182 per script, while Michigan achieves both high capture and lower costs at $2,317 per script.  

What Employers Can and Can’t See

These wide variations raise an important question: Do employers know what they're paying for biosimilars? The range in our data supports the idea that employers may face limited visibility into which specific biosimilars their plans utilize. Employers might see reports showing "biosimilar adoption" but can't tell if they're paying $639 or $2,655 per prescription without digging into detailed claims data. Even employers with pricing transparency still face rebate opacity; they can see what they paid, but not the manufacturer rebate, or why certain biosimilars made the formulary while cheaper options didn't.

What This Means For Employers

The $6,081 per-prescription gap between employers in our highest-cost state (DC) and lowest-cost state (Michigan) represents significant potential savings...or losses. Based on these findings, employers should ask:

Is Yusimry on your formulary? At $639 per script, it costs 76% less than Amjevita ($2,655).

What's your weighted average adalimumab cost? Our data shows employer averages ranging from $2,306 to $8,387.

Does your plan design support lowest-cost options? Copay structures, formulary tiers, and employee awareness all influence whether your plan captures the best biosimilar pricing.

With dozens of biosimilars for other specialty drugs entering the market in 2025-2026, these patterns may preview broader challenges ahead.

Methodology Note: This analysis examines prescription data from 956 self-funded employers, analyzing adalimumab (Humira and biosimilar) utilization patterns and costs in 2024. The data represents actual prescription costs before manufacturer rebates.

This analysis is part of Nomi Health's Trends in Spend series, examining healthcare spending patterns through employer claims data. Subscribe for monthly data analysis. Follow on LinkedIn for ongoing updates.

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