Simponi and Simponi Aria contain the same active drug, golimumab, but they differ in how you receive them, how often you take them, what conditions they treat, and how they’re billed to insurance. Simponi is a self-injectable shot you give yourself at home once a month. Simponi Aria is an IV infusion administered by a healthcare professional, typically every eight weeks after the initial doses.
How Each One Is Administered
Simponi comes as a prefilled syringe or a prefilled autoinjector pen. You inject it under the skin (subcutaneously), and most people do this at home after initial training. The injection itself takes just seconds.
Simponi Aria is delivered through an IV line over about 30 minutes in a clinic or infusion center. A healthcare professional prepares the solution from a vial, dilutes it, and monitors you during the infusion. You cannot give yourself Simponi Aria at home.
Dosing Schedule and How the Dose Is Calculated
Simponi uses a flat dose: 50 mg once a month for most conditions, regardless of body weight. For ulcerative colitis, the maintenance dose is 100 mg every four weeks. Because the dose is fixed, you get the same prefilled device each time.
Simponi Aria uses weight-based dosing at 2 mg per kilogram of body weight. That means a 70 kg (154 lb) person receives 140 mg per infusion, while a 90 kg (198 lb) person receives 180 mg. The schedule starts with infusions at week 0 and week 4, then shifts to every 8 weeks for ongoing treatment. So after the initial loading period, you visit the infusion center roughly six or seven times a year rather than giving yourself 12 monthly injections.
Approved Conditions
Both formulations treat rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis in adults. Beyond that overlap, their approved uses diverge.
- Simponi only: approved for moderately to severely active ulcerative colitis in adults. Simponi Aria does not carry this indication.
- Simponi Aria only: approved for active polyarticular juvenile idiopathic arthritis and psoriatic arthritis in children as young as 2 years old. Simponi does not have pediatric approvals for these conditions.
For rheumatoid arthritis specifically, both formulations are used in combination with methotrexate. The FDA has noted that the safety and effectiveness of switching between the IV and subcutaneous versions have not been established, so the two are not treated as interchangeable.
How the Drug Gets Into Your System
When golimumab is given intravenously, it enters the bloodstream directly, so 100% of the dose is immediately available. The subcutaneous version absorbs more slowly through tissue under the skin, and its absolute bioavailability is estimated at about 53%. This difference in absorption is one reason the dosing amounts and schedules differ between the two products. It doesn’t mean one works better than the other; the doses were designed to achieve effective drug levels through each route.
Insurance and Cost Considerations
The way each formulation is billed to insurance often differs in a way that matters for your out-of-pocket costs. Simponi Aria, as a provider-administered infusion, is typically covered under your medical benefit. For Medicare patients, that means Part B. Simponi, as a self-administered injection, usually falls under the pharmacy benefit, which for Medicare patients is Part D.
This distinction can significantly affect copays, deductibles, and prior authorization requirements depending on your specific plan. Some patients find better coverage under their medical benefit, while others do better under their pharmacy benefit. Checking both sides of your coverage before starting treatment is worth the effort.
Storage and Handling at Home
If you use Simponi at home, you need to store the prefilled syringe or autoinjector in the refrigerator between 36°F and 46°F, in the original carton to protect it from light. If needed, you can keep it at room temperature (up to 77°F) for a single period of up to 30 days, but once it’s been at room temperature, it cannot go back in the fridge. After 30 days out of refrigeration, it must be discarded. You should never freeze or shake it.
Simponi Aria doesn’t require any home storage since it’s kept and prepared at the infusion center.
Lifestyle and Convenience Tradeoffs
The choice between Simponi and Simponi Aria often comes down to practical preferences beyond the medical indication. Simponi offers the convenience of self-injection at home on your own schedule, with no travel to a clinic. Some people prefer the independence and the minimal time commitment of a quick monthly injection.
Simponi Aria means fewer doses per year (about 7 versus 12) and no responsibility for storing or handling medication at home. Some patients also feel more confident receiving treatment under medical supervision, particularly if they have concerns about self-injection or want a healthcare team monitoring for reactions in real time. The tradeoff is the time spent traveling to and sitting through each infusion appointment.