Study Highlights Role of Health Plan Type in Biosimilar Adoption

Low-flexibility plans, such as health maintenance organizations and exclusive provider organizations, were more likely to initiate biosimilar therapies than more flexible plans, according to a recent analysis published in PharmacoEconomics.

The study highlighted that plan type influences biosimilar adoption for both new-starts and switches from the originator to a biosimilar among US patients, and optimizing plan design to boost biosimilar use could generate savings and improve patient access to medications.

“This study reveals that health plan type may have an important impact on switching behavior and biosimilar initiation…. We recommend that future research explore why these plan type differences exist. For example, are certain types of plan more likely to receive larger rebates for biosimilars than others?” the authors noted.

Authors utilized IBM MarketScan Commercial Claims and Encounters pharmacy claims database to identify patients who switched to biosimilars or started treatment with a biosimilar for 6 biologic-biosimilar pairs from January 2015 to December 2019:

• Avastin (bevacizumab) vs Mvasi (bevacizumab-awwb)
• Epogen/Procrit (epoetin alfa) vs Retacrit (epoetin alfa-epbx)
• Neupogen (filgrastim) vs Nivestym (filgrastim- aafi)
• Neopogen (filgrastim) vs Zarxio (filgrastim-sndz)
• Remicade (infliximab) vs Inflectra (infliximab-dyyb)
• Neulasta (pegfilgrastim) vs Fulphila (pegfilgrastim-jmdb)

In the analyzed sample, 3% of claims corresponded to individuals who switched to biosimilars, while 8% were initiators, indicating a significant market potential for biosimilar production. Overall, there were 63,472 patients who switched and 66,927 patients who started therapy with a biosimilar. Plans were split into 3 categories: high-deductible, low-flexibility, and high-flexibility.

In the study, individuals enrolled in low-flexibility plans exhibited a 2% higher likelihood of becoming biosimilar initiators compared to those in high-deductible plans, indicating a significant 33% increase in the probability of transitioning to a biosimilar. Conversely, enrollment in high-flexibility plans was linked to a reduced probability of being a switcher (0.9% lower) and a lower probability of being a biosimilar initiator (1.0% lower) in comparison to high-deductible plans.

The study proposed exploring plan-related differences, such as potential financial incentives in capitated insurance forms and negotiation capabilities due to limited formularies.

The study acknowledged limitations, focusing on pharmacy claims data, and recommended further research to understand trends in outpatient settings. Understanding health plan influence on biologics and biosimilars was crucial for policymakers and stakeholders aiming to increase biosimilar adoption and reduce drug spending. The authors recognized the challenge for policymakers and researchers as biosimilars gained interchangeability approval. However, data limitations, particularly the absence of rebate information in the dataset, hindered a comprehensive exploration of plan-related drivers.

Reference

Costin J, Mouslim MC, Socal MP, Trujillo A. Exploring the influence of health insurance plans on biosimilar adoption Rates. Pharmacoecon Open. 2024;8(1):115-118. doi:10.1007/s41669-023-00447-6