HCPCS Code Q5104: Injection, infliximab-abda, biosimilar, (Renflexis), 10 mg

HCPCS Code Q5104 covers infliximab abda biosimilar Renflexis 10 mg for rheumatoid arthritis, Crohn’s disease, ulcerative colitis, and psoriatic arthritis.

Use Code

## **What is HCPCS code Q5104?** HCPCS Code Q5104 is the HCPCS Level II code for infliximab-abda, a biosimilar to infliximab marketed under the brand name Renflexis®. Each billing unit of Q5104 represents 10 mg of infliximab-abda administered via intravenous infusion. This product-specific code was created by CMS effective April 1, 2018, to distinguish Renflexis from other infliximab biosimilars such as infliximab-dyyb (Inflectra®) and infliximab-axxq (Avsola®). Q5104 is classified under the HCPCS category for drugs, biologicals, and chemotherapy administration for Medicare payment purposes. While infliximab-abda is not used for traditional cancer chemotherapy, it is treated as a therapeutic biologic and reimbursed under the same payment grouping, ensuring consistent claims processing and payment methodology under the OPPS. Renflexis is a tumor necrosis factor (TNF) blocker used to treat a range of autoimmune and inflammatory conditions, including rheumatoid arthritis (in combination with methotrexate), Crohn’s disease (adult and pediatric), ulcerative colitis, ankylosing spondylitis, psoriatic arthritis, and plaque psoriasis. Clinical monitoring may involve swollen joint count, tender joint count, and disease activity indices to track patient progress. Providers typically document prior or other systemic therapies initiated prior to infliximab treatment, particularly in cases where conventional therapy was inadequate. Medical necessity documentation often includes evidence of closely monitored patient response, noting resolution or persistence of symptoms, and may reference unspecified site involvement, multiple sites, or unspecified complications when applicable. Providers should also record any adverse outcomes or immune-related conditions such as host–disease reactions, ensuring that claims accurately reflect the patient’s treatment plan and clinical status.

## **HCPCS code Q5104 documentation requirements** Accurate documentation is required to support medical necessity and ensure proper reimbursement when billing HCPCS code Q5104: ### **Patient diagnosis and clinical justification** Medical records must document the diagnosis being treated and provide clinical justification for infliximab-abda therapy. This should follow accepted clinical guidelines (e.g., ACR/EULAR for rheumatoid arthritis, ACG for Crohn’s/ulcerative colitis) and include relevant signs and symptoms such as joint swelling/tenderness, GI bleeding, skin plaques, or other indicators of active disease. ### **Weight-based dosing** Because infliximab is dosed by weight, patient weight at the time of infusion must be recorded in the medical record to justify the total number of units billed (1 unit = 10 mg). ### **Screening requirements** Documentation must confirm screening for latent tuberculosis infection prior to initiation of therapy, with treatment initiated if positive, as required by infliximab’s FDA label. ### **Prior therapy and medical necessity** When required by payer policy, records must show inadequate response, intolerance, or contraindication to conventional non-biologic therapies before starting infliximab-abda. This may include prior use of corticosteroids, immunomodulators, or other DMARDs. ### **Administration details** The medical record must specify: - Total dose administered and number of units billed. - Date and time of infusion. - Infusion site and provider administering the drug. - Any adverse events or treatment interruptions. ### **Diagnosis and medical necessity** Include ICD-10-CM diagnosis codes that meet coverage criteria under CMS LCD A52423 or payer policy (e.g., M05.xx for RA, K50.xx for Crohn’s). Ensure documentation of prior therapy failure or contraindications is on file if required.

## **HCPCS Q5104 billing requirements** Correctly billing HCPCS code Q5104 is essential to ensure proper reimbursement and avoid claim denials ### **Report correct number of units** Each billing unit for Q5104 represents 10 mg of infliximab-abda. Report the total number of units that match the actual dose administered (e.g., 300 mg infusion = 30 units). The billed dose must match the patient’s weight-based order in the medical record. ### **Revenue code and bill type** For hospital outpatient claims, use revenue code 0636 (drugs requiring detailed coding) and the appropriate bill type (e.g., 13X). For physician office claims, submit under the appropriate place of service and use Q5104 on the CMS-1500 claim form. ### **JW and JZ modifiers for wastage** When billing Medicare or commercial payers that follow CMS policy, use: - **JW modifier** – To report the amount of drug discarded from a single-use vial. - **JZ modifier** – Required by CMS (as of July 1, 2023) when no wastage occurred, to confirm that no drug was discarded. ### **NDC reporting** Many payers require inclusion of the National Drug Code (NDC) on the claim, including package size, quantity, and unit of measure. This supports correct pricing and payment. ### **Modifiers for coverage confirmation** Append the KX modifier when documentation supporting medical necessity is on file. If coverage criteria are not met but the provider proceeds with treatment, submit with GA (ABN on file) or GZ (no ABN) to indicate patient financial responsibility.

## **Other relevant codes** - **Q5103**: Injection, infliximab-dyyb, biosimilar (Inflectra), 10 mg - **Q5109**: Injection, infliximab-qbtx, biosimilar (Ixifi), 10 mg - **Q5121**: Injection, infliximab-axxq, biosimilar (Avsola), 10 mg - **J1745**: Injection, infliximab (the reference product, non-biosimilar), 10 mg

Frequently asked questions

HCPCS code Q5104 is for the injection of infliximab-abda, a biosimilar of Renflexis 10 mg, used in the management of autoimmune diseases, including rheumatoid arthritis, ulcerative colitis, Crohn’s disease, ankylosing spondylitis, psoriatic arthritis, and plaque psoriasis.

Infliximab abda treats autoimmune diseases like rheumatoid arthritis, Crohn's disease, ulcerative colitis, and plaque psoriasis by reducing inflammation and targeting tumor necrosis factor alpha in patients with active disease or inadequate response to conventional therapy.

Renflexis infusion average Medicare reimbursement is approximately $30.87 per 10 mg unit, but varies by payer, site of service, and systemic therapy protocols.

Remicade is the original infliximab drug, while infliximab biosimilars like Renflexis are similar versions with the same active ingredient. Providers use them interchangeably based on medical necessity, patient tolerance, and payer coverage.