Tremfya (Guselkumab) Infusion Therapy in New York

For most people prescribed Tremfya, it is not an infusion at all. Tremfya (guselkumab) is an interleukin-23 antagonist, and it is given by subcutaneous injection for plaque psoriasis and for psoriatic arthritis — the label sets out no intravenous regimen for either condition, at any age. An intravenous regimen exists only for adults with moderately to severely active ulcerative colitis or Crohn's disease, and even there it covers induction only: three infusions, at Week 0, Week 4 and Week 8. After Week 8 the patient moves to subcutaneous maintenance. The label provides no intravenous maintenance regimen for any indication.

The restriction is structural in the FDA-approved prescribing information, whose header reads "injection, for subcutaneous or intravenous use": intravenous dosing appears only inside Section 2.4, the single subsection shared by ulcerative colitis and Crohn's disease. The word "intravenous" does not appear in Section 2.2 (plaque psoriasis) or Section 2.3 (psoriatic arthritis) at all.

One headline is worth clearing up, because it misleads readers regularly. In September 2025 an all-subcutaneous induction option was added for ulcerative colitis, announced as making Tremfya "the first and only IL-23 inhibitor with a fully subcutaneous regimen". That approval added an option; it did not withdraw the intravenous one. The same announcement states Tremfya "is the first and only IL-23 inhibitor to offer both SC and intravenous (IV) induction options for the treatment of UC and Crohn's disease." Both induction routes remain on the current label.

Tremfya carries four FDA-approved indications, and the age limits differ sharply between them. Two are open to children; two are adults only — and the two adult-only indications are the same two that have an intravenous induction option, so no pediatric patient has an approved intravenous regimen.

• Moderate-to-severe plaque psoriasis in "adults and pediatric patients 6 years of age and older who also weigh at least 40 kg" who are candidates for systemic therapy or phototherapy. Subcutaneous only.
• Active psoriatic arthritis in "adults and pediatric patients 6 years of age and older who also weigh at least 40 kg." Subcutaneous only. The label notes Tremfya "may be administered alone or in combination with a conventional disease-modifying antirheumatic drug (e.g., methotrexate)."
• Moderately to severely active ulcerative colitis — adults only. This was the September 2024 approval that first brought an intravenous induction regimen onto the label.
• Moderately to severely active Crohn's disease — adults only, approved in March 2025 with both subcutaneous and intravenous induction options from the outset.

Section 8.4 of the label states that safety and effectiveness have not been established in pediatric patients with ulcerative colitis or Crohn's disease, nor in plaque psoriasis or psoriatic arthritis patients younger than 6 years or weighing less than 40 kg. The pediatric psoriasis and psoriatic arthritis indications were added in September 2025.

Stated plainly, so nobody is surprised: intravenous Tremfya for plaque psoriasis or psoriatic arthritis is off-label, as is intravenous maintenance dosing of any kind and any use in children with inflammatory bowel disease. The label describes no such regimens. Anything outside the four indications above is off-label and a matter for the prescribing clinician.

If your gastroenterologist has chosen the intravenous route, the regimen is 200 mg administered by intravenous infusion over at least one hour at Week 0, Week 4 and Week 8 — three visits, roughly a month apart, and then the intravenous course is finished. The alternative induction option for the same two conditions is subcutaneous: 400 mg given as two consecutive 200 mg injections on the same Week 0, Week 4 and Week 8 schedule. Which one is used is the prescriber's decision.

Maintenance is always subcutaneous, in one of two labeled regimens: 100 mg at Week 16 and every 8 weeks thereafter, or 200 mg at Week 12 and every 4 weeks thereafter. Note the different start weeks. In practice this means an infusion center's role in Tremfya care is deliberately short: three infusions, then a handover to self-administered or office-administered injections.

Before the first dose, the label directs clinicians to evaluate patients for tuberculosis infection, to obtain liver enzymes and bilirubin levels (required for ulcerative colitis and Crohn's disease; at baseline if clinically indicated for psoriasis and psoriatic arthritis), and to "complete all age-appropriate vaccinations according to current immunization guidelines."

What the preparation actually involves. The 200 mg/20 mL single-dose vial is the only intravenous presentation — pens, prefilled syringes and the One-Press injector are subcutaneous devices and are never infused. A clinician withdraws and discards 20 mL from a 250 mL bag of 0.9% Sodium Chloride Injection, adds the 20 mL of Tremfya to give a final concentration of 0.8 mg/mL, and infuses it through an infusion set with "an in-line, sterile, non-pyrogenic, low protein binding filter (pore size 0.2 micrometer)." The label instructs: "Do not infuse TREMFYA concomitantly in the same intravenous line with other medicinal products," and the diluted solution may be held at room temperature for up to 10 hours. Beyond the one-hour minimum infusion time, the prescribing information specifies no post-infusion observation period or total visit length; ask your care team what to plan for.

Tremfya's FDA-approved prescribing information does not include a boxed warning. That is a statement about the labeling and nothing more — it is not a comparison with any other medication and it does not mean the drug is without risk. The label's risks sit in the Contraindications and Warnings and Precautions sections, and they are real.

Contraindication. "TREMFYA is contraindicated in patients with a history of serious hypersensitivity reaction to guselkumab or to any of the excipients."

Warnings and Precautions (Section 5) cover five areas:

• Hypersensitivity reactions. "Serious hypersensitivity reactions, including anaphylaxis, have been reported with post market use of TREMFYA. Some cases required hospitalization." If one occurs, the label directs clinicians to discontinue Tremfya and initiate appropriate therapy.
• Infections. "TREMFYA may increase the risk of infection." Treatment should not be started in patients with any clinically important active infection until it resolves or is adequately treated, and should be held if a serious infection develops.
• Tuberculosis. Evaluate for TB before starting; do not administer to patients with active TB; treat latent TB first; and "monitor all patients for signs and symptoms of active TB during and after TREMFYA treatment."
• Hepatotoxicity. "Drug-induced liver injury has been reported." This one falls hardest on the same patients who may receive the infusion: for ulcerative colitis or Crohn's disease the label directs evaluation of liver enzymes and bilirubin "at baseline, for at least 16 weeks of treatment, and periodically thereafter," and interruption of treatment if drug-induced liver injury is suspected until that diagnosis is excluded.
• Immunizations. "Avoid use of live vaccines in patients treated with TREMFYA," and complete all age-appropriate vaccinations before starting therapy.

Read the full prescribing information and Medication Guide and discuss your own history with the clinician prescribing it.

Here is the thing to know before reading any percentage on this page: every ulcerative colitis and Crohn's disease adverse-reaction table in the Tremfya label reports the subcutaneous regimens. The label contains no induction-phase table comparing intravenous Tremfya 200 mg against placebo. So these figures describe the subcutaneous regimens that were studied, and they should not be read as the reaction rates for the infusion. "Injection site reactions" in particular is by definition a subcutaneous event and does not carry over to an infusion.

For plaque psoriasis, Table 1 pools trials PsO1 and PsO2 and reports reactions occurring in at least 1% of adults through Week 16 on subcutaneous 100 mg:

The label states the rate of serious infections in that trial set was "≤ 0.2%" for both the Tremfya and the placebo groups.

For Crohn's disease, Table 4 reports reactions in at least 3% of adults through Week 48 in Trial CD3, in subjects "treated with either recommended subcutaneous TREMFYA regimen":

Serious infections in Trial CD3 occurred in "1.5% of subjects treated with TREMFYA versus 0%" on placebo. For ulcerative colitis, the label reports two subcutaneous trials — Trial UC2 through Week 44 and Trial UC4 through Week 24 — in which the reactions reaching the 3% threshold were injection site reactions, arthralgia, upper respiratory tract infection, headache, gastroenteritis, fatigue, pyrexia and rash; serious infections occurred in "0.8% of subjects treated with TREMFYA versus 0%" on placebo. For psoriatic arthritis the label gives no dedicated table, stating the profile is generally consistent with plaque psoriasis "with the addition of bronchitis and neutrophil count decreased"; bronchitis was reported in 1.6% (every 8 weeks) and 2.9% (every 4 weeks) versus 1.1% on placebo over the 24-week placebo-controlled period.

Prime Infusions operates 13 infusion centers across New York, plus one in Atlanta. In New York those are Brooklyn and Boro Park in Brooklyn; Fresh Meadows, Astoria, Jamaica and Howard Beach in Queens; the Upper East Side in Manhattan; Staten Island; Great Neck in Nassau County and Inwood in the Five Towns; Port Jefferson Station in Suffolk County; and New City in Rockland County and Monroe in Orange County. Addresses are on our locations page, and our Atlanta center is listed there too. All centers are open Monday to Friday, 9:00AM to 5:00PM.

Which center is right for a given order is confirmed by our care team, not chosen from this page — per-center product availability and scheduling are not published, so call 718-443-4000 or send us a note through contact us before assuming a location.

Site of care is also a payer question, not only a convenience one. UnitedHealthcare's commercial "Provider Administered Drugs – Site of Care" policy, effective 1 August 2026, lists "Tremfya® (Guselkumab) (IV)" by name among the drugs subject to site-of-care review, and states that "Alternative Sites of Care, such as non-hospital outpatient infusion, physician office, ambulatory infusion suites, or home infusion services are well accepted places of service for medication infusion therapy." Under the same policy, hospital outpatient administration is not considered medically necessary unless specific clinical criteria are met — one of which is a carve-out for initial infusions or re-initiation after a gap of six or more months, for a limited duration. Whether any of that applies to a particular patient is a determination only that patient's plan can make.

The single most useful billing fact about Tremfya is that the same drug sits on two different benefits depending on how it is given. UnitedHealthcare's commercial medical benefit drug policy for Tremfya (2026D0134D, effective 1 May 2026) says it outright: "Tremfya (guselkumab) injection for intravenous use" is covered under the medical benefit, while "Tremfya (guselkumab) for self-administered subcutaneous injection is obtained under the pharmacy benefit." So a patient who receives intravenous induction and then moves to subcutaneous maintenance can expect the drug to change benefits partway through — a different deductible, a different plan process, a different bill.

Prior authorization is required at both payers researched here. UnitedHealthcare's policy states that "Authorization will be issued for 3 induction doses" for ulcerative colitis and for Crohn's disease, matching the Week 0/4/8 schedule. Its ulcerative colitis criteria require prior or concurrent inadequate response to oral corticosteroids and/or immunosuppressants, or prior treatment with a systemic targeted immunomodulator approved for ulcerative colitis; for Crohn's disease, a history of failure of corticosteroids, 6-mercaptopurine, azathioprine or methotrexate, or prior targeted immunomodulator treatment.

Aetna's Clinical Policy Bulletin 1011, last reviewed 29 June 2026, states that "precertification of intravenous guselkumab (Tremfya IV) is required of all Aetna participating providers and members in applicable plan designs." For plaque psoriasis and psoriatic arthritis its pathways are satisfied either by prior use of a biologic or targeted synthetic drug or by disease-severity criteria — so it is inaccurate to describe Aetna as imposing an absolute requirement to fail a TNF inhibitor first for those indications. Aetna considers concomitant use of guselkumab with another biologic or targeted synthetic drug for the same indication experimental and investigational.

Medicare splits along the same seam for a different reason. Part B excludes drugs "usually self-administered by the patient," defined by CMS as more than 50 percent of the time across all beneficiaries who use the drug and decided drug by drug; CMS's route-based presumptions treat intravenous drugs as not usually self-administered and subcutaneous drugs as usually self-administered. In practice that puts provider-administered intravenous induction on the Part B side, billed by the facility under HCPCS J1628 ("injection, guselkumab, 1 mg" — a 200 mg dose is 200 units, with the JA modifier for intravenous infusion), and pharmacy-dispensed subcutaneous maintenance generally on the Part D side. The final determination belongs to the beneficiary's plan and Medicare Administrative Contractor, and Medicare Advantage plans apply their own rules.

Coverage, prior authorization and out-of-pocket cost are determined solely by your health plan. Prime Infusions verifies benefits and submits the authorization request with your prescriber; we cannot guarantee approval. Physicians can send an order through our Treatment Referrals directory; patients can reach our care team at 718-443-4000 or through contact us.

The treatment goals in the conditions Tremfya is approved to treat include clearer skin, reduced symptoms of psoriatic arthritis, and improved physical function. Whether an individual patient reaches them varies, and is assessed by the prescribing clinician. The medication helps to reduce inflammation, providing relief from the discomfort of plaque psoriasis and psoriatic arthritis. The convenient dosing schedule—every eight weeks after the initial doses—makes Tremfya a practical option for long-term management of these conditions.