Briumvi CPT Code: A Realistic Guide to Infusion Coding (Without the Guesswork)

Let’s be honest for a second.

If you are looking for a single, magical “Briumvi CPT code” that you can copy and paste onto a claim form, you are going to feel a little frustrated.

That is not how medical coding works.

Briumvi (ublituximab-xiiy) is a relatively new player in the world of multiple sclerosis (MS) treatments. It is a monoclonal antibody, a CD20-directed cytolytic antibody. In plain English? It is an intravenous (IV) infusion medication that helps calm down an overactive immune system.

But when it comes to billing, the question always comes back to the same three words: briumvi cpt code.

Here is the truth. There is not one single code for “we gave Briumvi.” Instead, you will use a combination of HCPCS Level II codes (for the drug itself) and CPT® procedure codes (for the nursing time, the IV setup, and the monitoring).

This guide is not a copy-paste from a coding manual. It is a real-world, walk-you-through-it, honest conversation about how to get your Briumvi infusions paid correctly. No fluff. No fake leaks. Just practical help.

Table of Contents

First, Let’s Clear Up a Common Confusion

Many people search for “briumvi cpt code” because they think it works like an office visit code (99213) or a vaccine code.

It does not.

When you administer an IV infusion drug like Briumvi, you are billing for two separate things:

The drug itself (the actual liquid in the bag). This uses a J-code or a C-code (depending on the place of service).
The work of the infusion (the nurse’s time, the pump, the IV start, the monitoring). This uses CPT infusion codes (usually 96360, 96365, 96366, etc.).

Think of it like going to a coffee shop. You pay for the coffee (the drug), but you also pay for the barista’s time to make it (the procedure). Two different things.

So when we talk about the briumvi cpt code, we are really talking about a coding set.

The Official HCPCS Code for Briumvi (The Drug Itself)

Let’s start with the easiest part.

Briumvi has been assigned a specific HCPCS Level II code for the medication.

J2329 – Injection, ublituximab-xiiy, 1 mg

That is the code you will use to bill for the drug quantity.

How to use J2329 correctly

Briumvi is dosed based on a weight-adjusted regimen. But here is the standard induction dosing (always check the latest prescribing information, but this is the routine):

Day 1 (first infusion): 150 mg
Day 15 (second infusion): 450 mg
Every 24 weeks thereafter (maintenance): 450 mg

So, how do you bill the J-code?

You bill units. J2329 is per 1 mg.

For a 150 mg dose: 150 units of J2329.
For a 450 mg dose: 450 units of J2329.

Important Note for Readers:
Do not just bill “1” unit. That would mean you only gave 1 mg of the drug. Payers will deny that faster than you can say “medical necessity.” Always calculate the milligrams administered and bill that many units.

What about C-codes (hospital outpatient departments)?

If you are billing for a hospital outpatient department (like a hospital-based infusion center), you might use a C-code instead of a J-code for the drug. C-codes are specific to Medicare’s Outpatient Prospective Payment System (OPPS).

However, for Briumvi, as of this writing, the primary code remains J2329. C-codes are often assigned quarterly, so always check your Medicare Administrative Contractor (MAC) for updates. When in doubt, start with J2329 for physician offices and freestanding infusion centers. For hospitals, check your chargemaster.

The CPT Procedure Codes for Briumvi Infusion (The Nursing Work)

Now we get to the heart of what people mean when they search for “briumvi cpt code.” They want the procedure code for the infusion itself.

Because Briumvi is an IV infusion (not an injection, not a push), you will use the standard IV infusion CPT codes.

The main codes you will use

CPT Code	Description	When to use it for Briumvi
96365	IV infusion, for therapy, prophylaxis, or diagnosis (specify substance or drug); initial, up to 1 hour	The first hour of the Briumvi infusion.
96366	IV infusion, for therapy, prophylaxis, or diagnosis (specify substance or drug); each additional hour (List separately in addition to code for primary procedure)	Every hour after the first hour.
96360	IV infusion, hydration; initial, 31 minutes to 1 hour	Rarely used with Briumvi – this is for hydration only, not drug infusion. Do not use this for the drug itself.
+96361	IV infusion, hydration; each additional hour (List separately)	See above – not for drug infusion.

A realistic example: The first Briumvi infusion (Day 1 – 150 mg)

Let’s say the infusion itself takes 2 hours and 15 minutes from start to finish (not including pre-meds or a saline flush afterward).

Here is what you bill:

96365 (initial hour of the drug infusion)
+96366 x 2 (two additional hours – the second hour and the third hour, even if the third hour was only 15 minutes, because you bill in whole hours per most payer rules)

Pro tip: Most payers follow the “midnight rule” or the “hour rule” for infusion coding. If you go into the second hour by even 1 minute, you bill 96366. If you go into the third hour, you bill another 96366. Always check your specific payer’s infusion time rounding policy. Some use the “less than or equal to 30 minutes” rule for subsequent hours. When in doubt, bill the time you actually infused.

What about pre-medications?

Before Briumvi, patients often receive pre-meds to reduce infusion reactions. Common pre-meds include:

Acetaminophen (oral or IV)
Antihistamines (like diphenhydramine – oral or IV)
Corticosteroids (like methylprednisolone – IV push)

These are separately billable if documented.

Oral pre-meds are generally not billed (they are included in the E/M or administration overhead).
IV push pre-meds (like IV diphenhydramine or IV methylprednisolone) can be billed with 96374 (IV push, initial) and 96375 (each additional sequential IV push).

But be careful. Many payers consider these pre-meds as part of the infusion “wrap-around” service. The safest approach? Check your payer policies. Some want you to bundle them. Some allow separate billing.

A Realistic Sample Encounter (So You Can Visualize It)

Let’s walk through a full Briumvi maintenance visit.

Scenario: A patient comes in for their 450 mg maintenance infusion (every 24 weeks). The infusion time is 3 hours and 10 minutes.

Step 1: Pre-meds (15 minutes of IV push steroids and Benadryl)

CPT 96374 (IV push, initial) – for the first push (e.g., methylprednisolone)
CPT 96375 (each additional push) – for the diphenhydramine push

Step 2: The Briumvi infusion

The nurse starts the Briumvi drip at 10:00 AM. It runs until 1:10 PM.
Total infusion time = 3 hours 10 minutes.
Billing:
- 96365 (first hour)
- +96366 (second hour)
- +96366 (third hour – because you go into the third hour, and then you have 10 minutes of a fourth hour? No. Stop. You bill for the hours you completed. You completed 3 full hours and 10 minutes. Most payers allow you to bill the third hour (96366) and ignore the final 10 minutes if it is less than 31 minutes. If it were 31+ minutes, you’d bill a fourth 96366. Check your payer.)
- Simpler rule: Many coders bill 96365 + 96366 x 2 for a 3 hour 10 minute infusion. They do not bill a fourth line for the 10-minute overhang.

Step 3: The drug (Briumvi)

HCPCS: J2329 x 450 units (because 450 mg administered)

Step 4: An evaluation and management (E/M) service?

Maybe. If the patient has a significant, separately identifiable problem (e.g., a new rash, fever, change in status), you can bill an office visit (e.g., 99212-99215) with modifier -25 (significant, separately identifiable E/M service on the same day as a procedure).
Do not automatically bill an E/M just because the patient showed up. The infusion code includes some pre- and post-service work.

The Most Common Briumvi Coding Mistakes (And How to Avoid Them)

Even experienced billers make errors. Here are the top three mistakes with Briumvi.

1. Using hydration codes (96360) for the drug infusion

This is a big one. 96360 is for plain saline or LR (Lactated Ringer’s). It is for dehydration, not for administering a monoclonal antibody. If you bill 96360 for Briumvi, you are telling the payer, “We gave the patient salt water for three hours.” That is incorrect. And it is a compliance risk.

Fix: Always use 96365 for the initial hour of drug infusion and 96366 for each additional hour.

2. Billing J2329 incorrectly (wrong units or wrong strength)

Remember: J2329 is per 1 mg. Not per 10 mg. Not per 100 mg. Per 1 mg.

150 mg = 150 units
450 mg = 450 units

If you bill 1 unit for a 450 mg dose, you will get paid for 1 mg. That is a huge loss. If you bill 450 units for a 150 mg dose, you will be overpaid and audited.

Fix: Double-check your math. Document the total milligrams administered in your nursing notes. Then match your units to that number.

3. Not documenting the start and stop times

Without exact start and stop times (in military time, with minutes), you cannot defend your infusion codes. Payers deny claims for missing time documentation all the time.

Fix: In your infusion note, write:

Infusion start time: 10:00
Infusion stop time: 13:10
Total infusion time: 3 hours 10 minutes
Breakdown: 96365 (10:00-11:00), 96366 (11:00-12:00, 12:00-13:00), plus 10 minutes not billed.

Does Insurance Cover Briumvi Infusion Coding?

This is the part where we stay honest.

Briumvi is expensive. And the CPT codes for infusion are not the barrier. Most payers (Medicare, Medicaid, commercial plans like UnitedHealthcare, Anthem, Cigna, Aetna) cover medically necessary MS treatments.

But.

They will audit Briumvi claims closely because it is a specialty drug.

Prior authorization is almost always required

You cannot just code Briumvi and hope for the best. The prescribing provider must obtain prior authorization (PA) before the first infusion. The PA will include:

The diagnosis (MS – typically relapsing forms, G35)
The planned dosing regimen
Documentation of failure or intolerance to another MS therapy (often required)

If you bill without a PA, you will get a denial. That denial will say: “Not a covered benefit” or “Prior authorization required.”

Medical necessity documentation

Your medical record must answer one question: Why Briumvi?

Do not just say “MS.” Say:

“Patient has relapsing-remitting multiple sclerosis (RRMS).”
“Patient failed intravenous immunoglobulin (IVIG) due to….”
“Patient had an infusion reaction to ocrelizumab (Ocrevus).”
“Patient prefers a twice-yearly infusion after discussing risks/benefits.”

The more specific you are, the harder it is for a payer to deny.

A Quick Reference Table: Briumvi Coding at a Glance

What you are billing	Code	Units / Modifiers	Typical reimbursement (estimate – varies wildly)
Briumvi drug (per 1 mg)	J2329	Number of mg given	Varies by contract; ask your payer
Initial hour of infusion	96365	1	$80 –$ 80–150 depending on region
Each additional hour	96366	1 per extra hour	$50 –$ 50–90 per hour
IV push pre-med (first)	96374	1	$60 –$ 60–100
Each additional push	96375	1 per sequential push	$40 –$ 40–70
Office visit (same day, separate issue)	99212-99215	Modifier -25	Varies (but cannot be billed routinely)

Important Note: Do not copy these reimbursement numbers into your fee schedule. They are ballpark facility/physician work RVU conversions. Actual payment depends on your region, your payer contract, your place of service (office vs outpatient hospital), and the year. Always check your own fee schedule.

Facility vs. Non-Facility: Why It Matters for Briumvi CPT Codes

Where you give the infusion changes how you code and bill.

Non-facility (physician office, freestanding infusion center)

You use J2329 for the drug.
You use 96365, 96366 for the infusion.
You bill under the physician’s NPI or the group’s NPI.
You also bill for the drug acquisition cost (invoiced amount) plus a markup (depending on your payer).

Facility (hospital outpatient department, hospital-based infusion center)

You may use a C-code instead of J2329 for the drug if required by Medicare OPPS. Check your quarterly addendum.
You still use 96365, 96366 for the infusion.
The hospital bills for the facility resources (the chair, the nurse, the pump). The physician may bill separately for the professional component (often a prolonged service code or E/M code, depending on the model).

If you are a patient reading this: your out-of-pocket cost may be different at a hospital vs. an office. Hospitals often add a facility fee. Always ask for a cost estimate.

How to Audit Your Own Briumvi Claims (A 5-Minute Checklist)

Before you hit “submit” on your claim form (or before you send it to your billing service), run through this checklist.

J2329 units = total milligrams administered (e.g., 450 units for a 450 mg dose).
96365 billed once for the first hour of the Briumvi drip (not for hydration).
96366 billed for each full or partial additional hour (per your payer’s rounding rule).
Modifiers – Did you use -25 on an E/M code? Only if there was a separately identifiable visit. Did you use -59 or -XU? Rarely needed for standard infusion unless you have a bizarre scheduling conflict.
Diagnosis code – G35 (Multiple sclerosis) is linked to the J-code and the infusion codes. Do not accidentally link a Z-code (e.g., routine health check).
Place of service (POS) – Correct? 11 = office. 19 = off-campus outpatient hospital. 22 = on-campus outpatient hospital.
Referring provider – Commercial plans often want the referring neurologist’s NPI in loop.

Frequently Asked Questions (FAQ)

1. Is there a specific CPT code just for Briumvi itself?

No. The infusion procedure codes (96365, 96366) are drug-agnostic. They are used for hundreds of IV drugs. The drug is identified by the HCPCS code J2329.

2. Can I bill 96366 for a 10-minute additional infusion?

Generally, no. Most payers require that you pass the 30-minute mark to bill an additional hour. If you infuse for 1 hour and 10 minutes total, you bill 96365 (first hour) and nothing for the 10 minutes unless your payer has a “partial hour” policy that says 8-22 minutes is billable (very rare). When in doubt, do not bill under 31 minutes for an additional hour.

3. What ICD-10 code should I use for Briumvi?

G35 (Multiple sclerosis). That is it. Do not use a symptom code (R53.83 for fatigue) unless the payer explicitly asks for it. Link G35 to every line (J2329, 96365, 96366).

4. Does Medicare cover Briumvi infusion?

Yes, Medicare Part B covers Briumvi because it is an infused drug administered in a clinical setting (not self-injected). However, you must follow Medicare’s infusion time rules (often the “8 minutes or more” rule for timed codes). Check your local MAC’s infusion policy.

5. What happens if I use the wrong CPT code for the infusion?

The claim may deny, or worse, it may pay incorrectly. If you use 96360 (hydration) instead of 96365, the payer will pay the hydration rate (which is lower). You will lose money. If you overbill units on J2329, that is fraud. Always double-check.

6. I saw a “C-code” for Briumvi online. Is that real?

Possibly. Medicare assigns C-codes to new drugs for hospital outpatient billing. As of this writing, J2329 is the primary code. If a C-code exists, it will be listed on the CMS website and your MAC’s fee schedule. Do not use a C-code in a physician office – that will deny.

7. Can a patient get Briumvi at home?

Extremely unlikely. Briumvi requires an IV infusion with pre-meds and monitoring for infusion reactions. Home infusion is not the standard of care for the first several doses. Some specialty pharmacies offer home infusion for maintenance, but that is rare and requires significant coordination. Coding for home infusion uses different CPT codes (99601, 99602). That is a whole different article.

Additional Resources (Where to Go for the Official Truth)

Do not rely on a single blog post (even this one) for final coding decisions. Bookmark these links.

CMS HCPCS Quarterly Update – Search for J2329 to see official status indicators and payment limits.
- Link: www.cms.gov/medicare/coding-billing/healthcare-common-procedure-coding-system-hcpcs (Search for J2329)
Briumvi Official Prescribing Information (PI) – Always check the PI for dosing updates. The FDA label is the source of truth.
- Link: Search “Briumvi FDA label” on www.accessdata.fda.gov
Your Local Medicare Administrative Contractor (MAC) – Every region has a MAC (e.g., Noridian, Novitas, Palmetto GBA). Go to their website and search for “infusion coding guideline” or “local coverage determination (LCD) for MS treatments.”
American Medical Association (AMA) CPT® Codebook – For the official language of 96365, 96366, and the infusion coding rules.

Pro tip: Do not copy-paste codes from forums or social media. Go to the source. The CMS website is free. Your MAC’s website is free. Use them.

A Note for Patients (If You Are Searching for Briumvi CPT Codes)

If you are a person living with MS, you might be looking up these codes because your bill looks confusing. That makes sense.

Here is what you need to know:

You will likely see J2329 on your explanation of benefits (EOB). That is the drug itself.
You will see 96365 or 96366 – that is the nursing time.
You will see G35 – that is your diagnosis.

If your insurance denies a claim, do not panic. Often it is a coding error (wrong units, missing modifier, no prior auth). Call your provider’s billing office first. They want to get paid. They will fix it.

If you have a high out-of-pocket cost, ask about co-pay assistance. The manufacturer of Briumvi (TG Therapeutics) offers a patient support program. Do not stop treatment because of a bill before you call them.

The Future of Briumvi Coding (What Might Change)

Medical coding is not static.

Three things could change in the next 12-24 months:

A dedicated C-code for hospital outpatient billing – If Briumvi usage grows, CMS may assign a stable C-code.
Home infusion guidance – If the FDA or payers approve home maintenance infusions, we may see more use of 99601/99602.
New J-code – Unlikely. J2329 is relatively new. It will stick around for years.

What will not change? The fact that you need to use infusion procedure codes (96365, 96366) for IV drug delivery. That system has been stable for over a decade.

Conclusion (Three Lines to Remember)

Line 1: There is no single “Briumvi CPT code”; instead, you need J2329 for the drug (units = milligrams given) and 96365 (first hour) plus 96366 (each additional hour) for the infusion work.

Line 2: Always document exact start/stop times, obtain prior authorization, and link the G35 diagnosis code to every service line to avoid automatic denials.

Line 3: When in doubt, go to your local MAC or the CMS HCPCS lookup – free, official sources are better than any forum or outdated blog.

Additional Resource Link

[📄 Download the Briumvi Coding One-Page Cheat Sheet (PDF) – Not real, but you can create one]

Suggested real resource: Go directly to the CMS HCPCS Application Summary for J2329 at:
🔗 https://www.cms.gov/medicare/coding-billing/healthcare-common-procedure-coding-system-hcpcs/quarterly-updates (Then search “J2329” in your browser)

Briumvi CPT Code: A Realistic Guide to Infusion Coding (Without the Guesswork)

First, Let’s Clear Up a Common Confusion