Persistence with biologic therapies in the Medicare coverage gap

Area of Science:

• Health Economics
• Pharmacoeconomics
• Health Services Research

Background:

• Medicare Part D plans feature a coverage gap, impacting patient out-of-pocket costs for prescription drugs.
• Understanding medication persistence is crucial for evaluating treatment effectiveness and healthcare costs.

Purpose of the Study:

• To compare persistence with teriparatide and other biologic therapies in Medicare Part D plans with and without a coverage gap.
• To assess the impact of the coverage gap on medication adherence for osteoporosis and other conditions.

Main Methods:

• Retrospective cohort study of Medicare Part D beneficiaries comparing plans with and without a coverage gap.
• Included patients using alendronate, teriparatide, etanercept, adalimumab, interferon β-1a, or glatiramer acetate.
• Defined discontinuation as failure to refill the index prescription after reaching the coverage gap.

Main Results:

• Patients using osteoporosis medications (alendronate, teriparatide) were more likely to discontinue treatment in plans with a coverage gap.
• Discontinuation rates for teriparatide were significantly higher in basic (coverage gap) plans (AOR=3.56).
• Persistence with etanercept, adalimumab, interferon β-1a, and glatiramer acetate did not significantly vary by plan type.

Conclusions:

• The Medicare Part D coverage gap is associated with increased discontinuation of osteoporosis medications.
• Eliminating the coverage gap may improve persistence with osteoporosis treatments.