Does Medicare Cover Tremfya?

The first time a Medicare patient sees the wholesale price of Tremfya — about $13,000 per dose, dosed once every eight weeks — they usually have the same reaction: surely Medicare will not let me actually pay anything close to that. The reaction is correct, mostly, in 2026. The Inflation Reduction Act’s $2,000 annual out-of-pocket cap means your real exposure is far below the gross cost. But the structure of how you reach that cap, and the prior authorization battles you may need to fight to get there, deserve more than a sentence of explanation.

Tremfya is one of those drugs where the right way to think about Medicare coverage is in two parts: getting access (a paperwork question) and managing cost (a math question). Most patients fixate on the cost question. The paperwork is what trips them up.

What Tremfya is and how it’s used

Tremfya (guselkumab) is a fully human monoclonal antibody manufactured by Janssen, the pharmaceutical arm of Johnson & Johnson. It blocks interleukin-23 (IL-23), a cytokine that drives several inflammatory diseases.

Tremfya is FDA-approved for:

• Moderate-to-severe plaque psoriasis in adults
• Active psoriatic arthritis in adults
• Moderately-to-severely active ulcerative colitis in adults

The dosing schedule for psoriasis and psoriatic arthritis is two loading doses (week 0 and week 4), then a maintenance dose every eight weeks. UC dosing is different — IV loading then subcutaneous maintenance, with maintenance usually every four weeks early on.

Patients tend to come to Tremfya after one or more biologic failures. The decision tree usually goes: a TNF inhibitor first (Humira, Enbrel, or a biosimilar), then if that fails, an IL-17 inhibitor (Cosentyx, Taltz) or an IL-23 inhibitor (Tremfya, Skyrizi). Tremfya gets selected when there’s a clinical reason to favor IL-23 inhibition specifically.

Specialty tier placement, in context

Every major Part D plan in 2026 places Tremfya on Tier 5 — the specialty tier. Tier 5 means coinsurance, not a flat copay. The standard specialty tier coinsurance is 33%, though some plans run lower (25–30%) for preferred specialty drugs.

What does that mean for your bill?

If your Part D plan charges 33% coinsurance for Tremfya and the plan’s negotiated price is around $13,000 per dose, the math is roughly $4,300 in coinsurance per fill. You’d hit your $2,000 annual cap before that first fill is even fully completed.

The new payment plan option (Medicare Prescription Payment Plan, launched 2025) is particularly relevant here. Instead of paying $2,000+ up front in January for your first Tremfya fill, you can elect to spread that $2,000 across monthly installments — about $167 per month. This is genuinely useful if you’re on a fixed income; the alternative is a January credit card bill for two grand.

Prior authorization and step therapy in detail

Almost every Part D plan requires PA for Tremfya. The PA form typically requires:

• ICD-10 diagnosis code
• Severity documentation (BSA for psoriasis; CASPAR criteria and joint count for PsA; Mayo score for UC)
• Prior medications tried and outcomes
• Patient weight (Tremfya is weight-based for some indications)

Step therapy patterns vary, but a common pattern looks like this for plaque psoriasis:

1. Topical corticosteroids → failed or not durable
2. Methotrexate or Otezla → failed, contraindicated, or not tolerated
3. TNF inhibitor (typically adalimumab/Humira or a biosimilar) → failed or contraindicated
4. Tremfya approved

Patients moving to Medicare from commercial insurance often hit a wall here because their step therapy history isn’t visible to the new Part D plan. The fix is to have your specialist’s office prepare a one-page treatment summary documenting the timeline and outcomes of every prior therapy. That summary becomes the foundation of the PA submission — and saves weeks of back-and-forth.

If your initial PA is denied, the appeal process is real and frequently successful. CMS data routinely shows that 50%+ of Part D coverage denials are reversed on redetermination when the prescriber submits robust supporting documentation.

The Otezla and Skyrizi adjacent landscape

Two adjacent drugs come up constantly when patients are evaluating Tremfya on Medicare:

Otezla (apremilast) is an oral medication, taken twice daily. It’s lower-cost than Tremfya at this point — particularly with generic apremilast now on the market — and many plans will require Otezla as a step before Tremfya for psoriasis. Otezla is generally less effective than Tremfya for severe psoriasis but works well for many patients with moderate disease.

Skyrizi (risankizumab) is the closest competitor — also an IL-23 inhibitor, same class. Skyrizi and Tremfya are roughly equivalent on efficacy for plaque psoriasis. Coverage is similar (both specialty tier, both PA required). Some plans prefer one over the other based on contracted pricing; check your plan’s formulary to see which is on a lower coinsurance level for you.

What happens to coverage if you respond well

A practical scenario worth thinking through: you start Tremfya, your skin clears completely, and your dermatologist suggests stretching the dosing interval from every eight weeks to every twelve. This is a common real-world practice for patients with good response. Medicare does not have a specific rule against it. As long as your prescriber writes the prescription and the pharmacist fills it accordingly, the plan adjudicates the claim normally.

The cost implication is meaningful. If you stretch from 6 doses per year to 4 doses per year, your Q1 still hits the $2,000 cap (one fill is enough), but your overall system cost drops substantially. Some prescribers have moved patients to less-frequent dosing for this reason.

Side-effect monitoring and Part B coverage

Tremfya monitoring is mostly minimal — periodic check-ins with your specialist, sometimes a TB screen at initiation. These visits are covered under Medicare Part B with the standard 20% coinsurance (which a Medigap policy would absorb).

If you develop side effects requiring evaluation — most commonly upper respiratory infections, but rarely opportunistic infections — those evaluations are also Part B services. The drug itself is Part D; the doctor visits are Part B.

Bottom line

Tremfya is covered by Medicare Part D for plaque psoriasis, psoriatic arthritis, and ulcerative colitis, with specialty tier coinsurance and prior authorization required by virtually every plan. The 2025 Part D redesign — particularly the $2,000 annual out-of-pocket cap and the Prescription Payment Plan option — makes Tremfya much more financially manageable than it was even two years ago. The remaining friction is bureaucratic: your prior authorization and step therapy history matters, and getting a clean treatment summary from your specialist’s office is the highest-leverage thing you can do to make Tremfya coverage work smoothly on Medicare.