Medicare Part D Coverage Variations for DMARDs Impacting Patient Access

A recent study published in Arthritis & Rheumatology spotlights variations in coverage for self-administered disease-modifying antirheumatic drugs (DMARDs) across Medicare Part D plans, potentially impacting treatment accessibility for individuals with rheumatoid arthritis (RA). Although advancements in biologic and targeted-synthetic DMARDs have enhanced treatment efficacy for RA, high costs have led insurers to impose coverage restrictions. This issue underscores the importance of understanding how insurance decisions can affect patient access to critical medications.

Researchers analyzed Medicare Part D formulary data from 2022 to 2026, evaluating coverage for drugs used in relapsed RA cases. The study reviewed 26,915 plan-year records, covering over 217 million beneficiaries, across stand-alone and Medicare Advantage (MA) Part D plans. Focused on DMARDs like tumor necrosis factor (TNF) inhibitors and Janus kinase (JAK) inhibitors, the study identified universal coverage for etanercept, adalimumab, and upadacitinib in over 94% of plans. However, drugs such as golimumab and abatacept exhibited lower coverage rates, highlighting discrepancies in payer strategies.

Significant differences in coverage emerged between plan types: only 10.4% of stand-alone plans and 37.6% of MA Part D plans offered comprehensive coverage of all drug mechanisms. Notably, coverage declined from 2025 to 2026, with abatacept included in just 0.3% of stand-alone plans and 21.2% of MA Part D plans by 2026. Conversely, coverage for tocilizumab improved, nearing universal availability. The study's authors stress the need for vigilant monitoring of Medicare Part D formularies in light of recent policy shifts affecting regulatory frameworks. Insurance professionals must stay informed about formulary decisions influencing patient access to essential medications.