Renflexis vs. Remicade

Both Renflexis and Remicade deliver infliximab, a TNF-alpha inhibitor used across multiple serious inflammatory conditions. TNF-alpha is a normal part of our immune system that can contribute to inflammatory conditions when overactive.

If your provider has recommended one and you want to understand how they differ, the clinical answer is straightforward: for all shared indications, they perform similarly. The more meaningful differences show up in cost, insurance coverage, and restrictions.

Here’s a closer look at the full Renflexis vs. Remicade comparison—mechanism, indications, side effects, dosing, switching, and cost. If you’re exploring specialty pharmacy support for complex biologic treatments, understanding what your options look like in practice is a solid starting point.

Infliximab and TNF Inhibition

Infliximab belongs to a class of medications called TNF inhibitors, or biologics that work by blocking tumor necrosis factor-alpha (TNF-α), a protein the immune system produces that drives inflammation. 

Elevated TNF-α plays a big role in tissue damage in conditions like Crohn’s disease, rheumatoid arthritis, and ankylosing spondylitis (a type of arthritis that mainly affects the spine). Infliximab binds to both the free-floating and anchored TNF-α proteins in the body, preventing the inflammation process from beginning

Acelpa Health and its affiliated specialty pharmacies—California Specialty Pharmacy (CSP), ContinuumRx (CRx), Hawaii Specialty Pharmacy (HSP), Continuum Health (CH), and Integrated Care Systems (ICS)—support patients managing inflammatory conditions across gastroenterology, rheumatology, and dermatology, coordinating benefits verification, insurance approval, and scheduling for both products. 

How Do TNF Inhibitors Work?

When infliximab binds to TNF-α, it neutralizes the protein before it can attach to its cell surface receptors. This disrupts the signaling chain that would otherwise trigger joint destruction, intestinal inflammation, or skin involvement.

The process of how it works is unique from other biologic medications—infliximab is not an interleukin inhibitor, a JAK inhibitor, or an integrin blocker. It specifically targets TNF-α, which is why patients who don’t respond to one TNF-alpha blocker may still respond to medications with completely different mechanisms of action.

One clinically important consideration: because infliximab is a chimeric antibody (partly mouse, partly human protein), combining it with an immunomodulator medication like methotrexate or azathioprine is often recommended to help infliximab work longer and reduce the risk of the immune system building up a resistance to the drug.

What Conditions Are Treated with Infliximab?

Both products are FDA-approved for the same indications—there are no differences in approved uses:

• Crohn’s disease (moderately to severely active, adults and children ≥6) (CD)
• Ulcerative colitis (moderately to severely active, adults and children ≥6) (UC) 
• Rheumatoid arthritis (with methotrexate) (RA)
• Ankylosing spondylitis (AS)
• Psoriatic arthritis (PsA)
• Plaque psoriasis (chronic severe) (PP)

What Is Renflexis?

Renflexis (infliximab-abda) was developed by Samsung Bioepis and received FDA approval in July 2017, making it the second infliximab biosimilar approved in the US, after Inflectra.

The “abda” suffix in its nonproprietary name is a standard four-letter distinguisher the FDA assigns to all biosimilar products to differentiate them from both the reference biologic and each other.

The table below summarizes the key differences between the two products:

Feature	Remicade	Renflexis
Active ingredient	Infliximab	Infliximab-abda
Product type	Reference biologic	FDA-approved biosimilar
FDA approval year	1998	2017
Manufacturer	Janssen Biotech (J&J)	Samsung Bioepis
Approved indications	CD, UC, RA, AS, PsA, PP	CD, UC, RA, AS, PsA, PP
Pediatric approval (CD/UC only)	Yes (≥6 years)	Yes (≥6 years)
Interchangeable designation	N/A	No
Typical cost	Higher	Lower

How Does the FDA Approve Biosimilars Like Renflexis?

Biosimilar approval is not the same as approving a generic drug.

Unlike generic drugs, which are exact chemical copies, biologics are made from living cells. So biosimilars must be shown to be highly similar but not identical, while having no meaningful differences in safety or effectiveness.

The FDA requires applicants to demonstrate biosimilarity through analytical studies comparing molecular structure and stability, pharmacokinetic studies confirming identical drug behavior in the body, and clinical trials confirming equivalent safety and efficacy. 

Is Renflexis Interchangeable with Remicade?

In states where permitted by law, an interchangeable biosimilar designation may allow a pharmacist to substitute Renflexis for Remicade at the time of dispensing without prior authorization, subject to applicable state-specific requirements.

A prescriber must intentionally choose Renflexis, or an insurer formulary policy may require it. This is separate from whether switching is clinically safe (studies show it is—see the dosing section), and it does not affect Renflexis’s demonstrated biosimilarity to Remicade.

Other Infliximab Biosimilars on the Market

Renflexis is one of several infliximab biosimilars available in the US. Inflectra (infliximab-dyyb, Celltrion) was the first, approved in 2016, followed by Ixifi (infliximab-qbtx, Pfizer) in 2017 and Avsola (infliximab-axxq, Amgen) in 2019. 

All share the same mechanism, indications, and dosing as Remicade. Which product a patient receives is usually determined by insurance formulary and dispensing agreements.

Efficacy, Safety, and Side Effects

For all shared indications, Renflexis and Remicade have no clinically meaningful differences in efficacy or safety. The FDA’s biosimilar standard requires this to be established before approval is granted.

Clinical Evidence for Biosimilar Efficacy 

Samsung Bioepis conducted comparative studies supporting Renflexis’s biosimilarity to Remicade, including clinical pharmacokinetic studies and efficacy trials in rheumatoid arthritis.

The FDA’s clinical review for Renflexis summarizes the clinical evidence package reviewed prior to approval. These studies confirmed equivalent response rates and comparable safety outcomes, consistent with what the analytical testing predicted.

Side Effects

Because Renflexis and Remicade contain the same active ingredient, their side effect profiles are identical.

Common side effects include:

• Infusion reactions (fever, chills, headache, itching, rash, hive, nausea, low blood pressure)
• Upper respiratory tract infections and sinusitis
• Urinary tract infections
• Fatigue and headache
• Nausea and abdominal discomfort
• Elevated liver enzymes on lab tests

Serious side effects that require prompt attention include:

• Serious infections, including bacterial sepsis, invasive fungal infections, and viral reactivation
• Reactivation of latent tuberculosis (TB)
• Hepatitis B reactivation in carriers
• Worsening heart failure
• Some nervous system disorders that affect nerves outside of the brain and spinal cord
• Severe liver reactions
• Lupus-like syndrome
• Severe hypersensitivity (allergic) reactions

Black Box Warnings and Pre-Treatment Screening

Infliximab carries two FDA black box warnings that apply equally to both products.

1. The first is for serious infections: by suppressing TNF-α, infliximab increases the risk of bacterial, viral, and fungal infections, including TB, histoplasmosis, and aspergillosis, some of which have been fatal. All patients must be tested for latent tuberculosis before starting, and the TB must be treated first.
2. The second warning covers malignancy (cancer): an increased risk of lymphoma has been observed in children, adolescents, and young adults on TNF blockers. Rare cases of a largely fatal type of cancer (hepatosplenic T-cell lymphoma) have been reported, primarily in patients also taking azathioprine or 6-mercaptopurine.

Pre-treatment screening for both products includes:

• TB skin test or blood test
• Hepatitis B testing
• Complete blood count and liver function tests
• Vaccination review (live vaccines before starting, not during treatment)
• Assessment for history of neurologic conditions or heart failure

Dosing, Infusion, and What to Expect

For both Remicade and Renflexis, dose and frequency depend on the condition being treated, body weight, and the treatment protocol established by the care team.

Infusions are administered intravenously and typically take two to three hours. Premedication—usually acetaminophen and an antihistamine, with corticosteroids for some patients—is given before each session to reduce reaction risk. The first infusion is monitored closely. If a reaction occurs, the care team can slow or pause the infusion and manage symptoms directly.

Your infusion therapy support throughout your treatment process is handled by the team at Acelpa Health’s affiliated pharmacies. We help coordinate with prescribing providers and help manage your medication scheduling and delivery.

Cost, Insurance, and Coverage

Cost is typically the most practical driver in the Renflexis vs Remicade decision. Biosimilars are generally priced lower than their reference biologics—often by 15 to 30 percent or more, depending on market conditions, contracting, and site of care. For patients managing a chronic condition that requires infliximab every 6 to 8 weeks for years, that difference can mean substantial savings on copays and total out-of-pocket costs.

But insurance formulary design often settles the question before a patient weighs in. Some plans have moved infliximab biosimilars to preferred tiers or require step therapy—meaning Renflexis must be tried before Remicade is covered. Checking with the insurance plan or a specialty pharmacy before starting your treatment can help clarify what the real cost difference looks like for a specific situation.

The team at Acelpa Health pharmacies can help navigate manufacturer-sponsored and foundation financial assistance programs and navigate your coverage in accordance with all applicable state and federal guidelines. We believe cost should never stand between a patient and the care they need.

Moving Forward with Infliximab Treatment

For most patients, the clinical choice between Renflexis and Remicade won’t affect how well treatment works. The biosimilarity evidence is strong, and dosing is identical. What changes is cost—and for a medication given every six to eight weeks over the years, that matters.

Acelpa Health and its affiliated specialty pharmacies work with patients who need infliximab across gastroenterology, rheumatology, and dermatology, helping handle prior authorization, insurance coordination, refill management, and care team communication.

Get in touch whenever you’re ready.

Frequently Asked Questions (FAQ): 

Is Renflexis the same as Remicade?

Not exactly—but clinically, they perform the same. Renflexis (infliximab-abda) is an FDA-approved biosimilar, while Remicade is the original reference biologic from Janssen. Both contain infliximab and are approved for all the same indications. The FDA required Renflexis to demonstrate no clinically meaningful differences in safety, purity, or effectiveness before approval.

What are the side effects of Renflexis infusion?

Because both products contain infliximab, their side effect profiles are identical. Common infusion-related effects include fever, chills, headache, itching, rash, and nausea—most are manageable by slowing the infusion rate or adjusting premedication. Serious risks include infections (including TB reactivation), hepatitis B reactivation, worsening heart failure, and rare cases of demyelinating disorders. Infliximab also carries FDA black box warnings for serious infections and malignancy risk in children and young adults.

What screening is required before starting infliximab?

All patients must be screened for latent tuberculosis (via skin test or blood test) before starting either product—this is an FDA-mandated requirement tied to the black box warning for serious infections. Hepatitis B testing is also required, as infliximab can cause reactivation in carriers. Providers will typically also order a complete blood count (CBC), liver function tests, and a vaccination review to ensure live vaccines are completed before treatment starts.

How much does Renflexis cost compared to Remicade?

Biosimilars are typically priced lower than their reference biologics—often 15 to 30 percent less, though actual cost depends heavily on insurance coverage, formulary tier, copay structure, and site of care. A specialty pharmacy benefits investigation can provide a personalized estimate. Manufacturer-sponsored and foundation financial assistance programs may be available from both manufacturers for eligible patients.

Is infliximab the best biologic for Crohn’s disease?

There is no single best option for everyone. Infliximab is one of several effective biologics for Crohn’s, and the right choice depends on disease severity, prior treatment history, other health conditions, and infusion versus self-injection preference. A gastroenterologist will evaluate the full picture and adjust therapy over time based on response.