Macular Degeneration Drug Prescribing Patterns After Step Therapy Introduction in Medicare Advantage

Area of Science:

• Health Economics
• Pharmacoeconomics
• Ophthalmology

Background:

• Step therapy is a cost-control strategy in Medicare Advantage (MA) for physician-administered drugs.
• Its impact on prescribing behavior for macular degeneration treatments remains unanalyzed.

Purpose of the Study:

• To evaluate the effect of step therapy on macular degeneration drug prescribing patterns.
• To assess changes in drug selection among 3 major MA insurers.

Main Methods:

• Retrospective analysis of 2017-2019 MA outpatient and carrier encounter data.
• Compared Humana (implemented step therapy) with Aetna and UHC (control group).
• Used difference-in-differences to analyze prescribing patterns for bevacizumab, aflibercept, and ranibizumab.

Main Results:

• Step therapy increased the probability of prescribing the preferred drug (bevacizumab) for initial administration by 7.8%.
• Predicted preferred-drug administration rose from 0.61 to 0.70 post-implementation.
• No significant increase in medication switching rates was observed (HR=0.86).

Conclusions:

• Step therapy is associated with increased use of preferred macular degeneration drugs for initial treatment.
• While influencing prescribing, step therapy alone did not ensure all administrations used the preferred agent.
• Further research may explore optimizing step therapy protocols.