Does biosimilar competition lower costs for patients?

Biosimilars have typically been viewed as cost-saving medications, but according to results of a study published in JAMA Health Forum, biosimilar competition did not consistently lower out-of-pocket costs for outpatients who were commercially insured. In fact, in some cases, costs even increased.

“Prices for biosimilars are typically 15% to 35% lower than their respective brand-name reference biologic, and can prompt the brand name manufacturers to lower prices or offer discounts,” noted the study authors. What they wanted to find out was whether biosimilar competition lowers costs for patients.

The researchers conducted a cohort study using a national commercial claims database and identified the out-of-pocket costs for those who were commercially insured across seven physician-administered biologics with a biosimilar available in the United States from January 2009 through March 2022. The biologics included filgrastim, infliximab, pegfilgrastim, epoetin alfa, bevacizumab, rituximab, and trastuzumab. The primary outcome was defined as out-of-pocket costs for the patient, such as deductible, copayment, and coinsurance.

Researchers performed two analyses to measure the association between biosimilar competition and out-of-pocket costs. In the first analysis, two biologics (rituximab and trastuzumab) were the only ones that showed significantly lower mean nonzero annual out-of-pocket spending after 2 years of biosimilar competition. The other drugs were either higher or did not yield significant changes. In the second analysis, researchers found that 28% of the reference biologic claims and 17% of biosimilars has nonzero out-of-pocket costs, but after adjustment, biosimilars were more likely to have nonzero out-of-pocket claims compared to the reference product.

An important takeaway for policymakers, said study authors, is to advocate for more targeted policy interventions that would make biologics and biosimilars affordable and accessible to patients who need them.