HCPCS code J0348: anidulafungin injection billing guide

Key takeaways

HCPCS code J0348 describes injection, anidulafungin, 1 mg, so each milligram administered equals one billable unit.

A 200 mg candidemia loading dose bills as 200 units, and the 100 mg maintenance dose bills as 100 units.

Esophageal candidiasis uses a 100 mg dose on day one, then 50 mg daily, which is 100 units and then 50 units.

Medicare Part B pays J0348 at ASP+6% in the physician office and the hospital outpatient setting, and the rate changes quarterly.

Practice management software like Pabau records the administration details in the chart, then pulls those values into a pre-filled claim.

HCPCS code J0348 is a Level II HCPCS J-code for injection, anidulafungin, 1 mg. Every billing decision on this echinocandin antifungal follows from that one-milligram unit. A 200 mg loading dose bills as 200 units, not as a single vial.

This guide covers the code definition, Medicare reimbursement, and the ICD-10 crosswalk. It also covers buy-and-bill steps, prior authorization, documentation requirements, the NDC crosswalk, and the denial patterns specific to this code.

HCPCS code J0348: code definition and quick reference

HCPCS code J0348 is a Level II HCPCS J-code maintained by the Centers for Medicare and Medicaid Services (CMS). It describes a single 1 mg unit of injectable anidulafungin, the echinocandin antifungal sold as Eraxis. The code applies to Medicare Part B, Medicaid, and most commercial payers when anidulafungin is physician-administered.

Quick-reference code details

About anidulafungin (Eraxis) and approved indications

Anidulafungin belongs to the echinocandin class of antifungals. It works by inhibiting glucan synthase, an enzyme fungal cells need to build their cell wall. The FDA approved it for adults with candidemia and other forms of invasive Candida infection, including esophageal candidiasis. It is given intravenously in an inpatient or outpatient infusion setting.

Coding J0348 correctly means restricting the claim to an FDA-approved indication. Off-label coverage varies by payer and needs individual review. For comparative pharmacology against the other echinocandins, read the Eraxis prescribing information.

• Candidemia: bloodstream infection with Candida species, including in immunocompromised patients
• Invasive candidiasis: peritonitis, abscesses, and other deep-tissue Candida infections
• Esophageal candidiasis: mucosal infection in patients who cannot tolerate oral antifungals
• Administration route: intravenous infusion only, at a dose set by the indication

Approved ICD-10 diagnosis codes for J0348

Every J0348 claim needs a supporting ICD-10 diagnosis code that matches the FDA-approved indication. A claim with no valid candidiasis or invasive fungal infection code is one of the fastest routes to a medical-necessity denial. The table below maps the most commonly paired ICD-10-CM codes to the clinical scenario each one describes. Verify currency against the CDC/NCHS ICD-10-CM web tool each fiscal year.

Use the most specific ICD-10 code available. B37.9 raises medical-necessity denial risk because it never documents why IV therapy was chosen over an oral or topical agent. Take the diagnosis from the chart, then confirm the descriptor in the ICD-10-CM code library before the claim is prepared.

How to bill J0348: units, dosing, and claim submission

The unit rule for J0348 is simple and still gets miscalculated under time pressure. One unit equals one milligram of anidulafungin administered, so the unit count is the milligram total. The dose itself depends on the indication, which is where the 50 mg and 100 mg figures get swapped.

Place J0348 on line 24 of the CMS-1500 for professional claims, with the applicable ICD-10 code in field 21. For UB-04 facility claims, use revenue code 636 for drugs requiring detailed coding and put J0348 in the HCPCS field. Medicaid claims must carry the NDC as a qualifier, and including it on every claim strengthens the audit record.

Pabau’s clinical records hold the dose, route, lot number, and NDC from the point of care. Its software for billing teams then pulls those recorded values into a pre-filled claim, so nobody retypes the unit count. The map below shows where each documented value belongs.

J0348 Medicare reimbursement and fee schedule

Medicare Part B pays physician-administered drugs like anidulafungin on the Average Sales Price methodology. The standard formula is ASP+6% in both the physician office and the hospital outpatient setting. CMS updates ASP-based rates every quarter, so any dollar figure has to be pulled for the quarter of administration. The rates live in the CMS ASP drug pricing files.

Because ASP rates move every quarter, never quote a per-unit figure to a patient without pulling the current rate from CMS. Check the rate at the start of each quarter. Then flag any J0348 claim whose expected payment was calculated on the previous quarter’s rate.

Medicaid and commercial payer rates for anidulafungin

State Medicaid programs set their own fee schedules for J0348. Rates vary widely by state and are not tied to the Medicare ASP formula, though many states use it as a reference point. Some states require prior authorization for J0348 in every clinical scenario. Commercial rates are negotiated in provider contracts and may sit above or below Medicare, so verify coverage and contract terms before you buy and bill.

Buy-and-bill process for J0348

Anidulafungin is a buy-and-bill drug. The practice purchases it, administers it, then bills the payer for reimbursement. The margin between acquisition cost and the ASP+6% rate decides the practice’s position on each claim. That margin only survives precise documentation at every step.

1. Acquire the drug: purchase anidulafungin from a licensed wholesaler, and record the acquisition cost and the NDC from the vial label at receipt.
2. Confirm medical necessity: obtain a signed physician order, confirm an FDA-approved diagnosis such as B37.7 or B37.81, and check prior authorization status before administration.
3. Administer and document: record the dose in milligrams, the time, the route, the lot number, and the administering provider. This record is the foundation of the J0348 claim.
4. Calculate units: take the milligram total as the unit count. Enter the NDC with qualifier N4 and the 11-digit number in the appropriate claim field.
5. Submit the claim: place J0348 and its unit count on the CMS-1500 line 24, or on the UB-04 under revenue code 636. Attach the supporting ICD-10 code and any required PA number.
6. Reconcile the remittance: compare the electronic remittance advice against the billed units and the ASP rate. Any variance should trigger a denial review.

J0348 prior authorization requirements

Traditional fee-for-service Medicare Part B does not usually require prior authorization for J0348. Medicare Advantage plans may impose their own PA requirements, and those vary by plan and plan year. Commercial payers frequently require PA for specialty antifungals, particularly high-cost IV agents like anidulafungin.

Verify authorization status with each payer before the drug is administered, not after. A claim submitted without a required PA number is denied on receipt and never reviewed for medical necessity. That makes the denial administrative rather than clinical, and appealing it costs more staff time than the original check would have.

• Traditional Medicare (Part B FFS): prior authorization is generally not required, though local coverage determinations should be checked with the MAC
• Medicare Advantage: PA is required by many MA plans, so check the plan’s list before each course of treatment
• Medicaid: requirements vary by state, and some states require PA for every echinocandin antifungal
• Commercial plans: PA is commonly required, with documentation of the diagnosis, any failed oral alternatives, and the prescriber’s credentials

Documentation requirements for clean claims

Auditors reviewing J-code drug claims look for one complete administration record. It has to connect the diagnosis to the drug, the drug to the dose, and the dose to the billed units. Any break in that chain is what a post-payment review finds first.

• Signed physician order naming anidulafungin, the dose in milligrams, and the route
• Confirmed ICD-10 diagnosis code supported by culture results or clinical findings in the chart
• Administration record with the date, time, dose in mg, route, infusion duration, lot number, and NDC from the vial label
• Prior authorization number, where the payer requires one
• NDC in 11-digit format with qualifier N4 on the claim
• Units calculated from milligrams administered, never from vials opened or purchased
• Medical necessity notes, including evidence that oral therapy is contraindicated or has failed in esophageal candidiasis

Documenting at the point of care keeps what is billed identical to what was recorded. When the administration record and the claim sit in the same system, the unit count carries over without manual re-entry.

NDC to HCPCS crosswalk for anidulafungin

Medicaid programs and many commercial payers require the National Drug Code on J0348 claims. The NDC has to match the product actually administered, not just the HCPCS code. For Eraxis, the NDC is specific to Pfizer’s package configuration. Generic anidulafungin carries different numbers, so confirm that the generic product’s NDC maps to J0348 in the current CMS HCPCS crosswalk files before you bill.

Medicare Part B does not mandate NDC reporting on professional claims, though including it improves audit defensibility. Medicaid requires it under federal drug rebate program rules. Submit it in 11-digit 5-4-2 format with qualifier N4, and verify the current requirement with each state Medicaid program and commercial payer.

Compliance and supply-chain documentation meet at this field. The practice may switch between the brand and a generic during a course of treatment. Each claim’s NDC then has to reflect the product administered on that date of service.

Related HCPCS codes and echinocandin alternatives

When anidulafungin is unavailable or clinically inappropriate, two other echinocandins carry their own HCPCS J-codes. Billing the wrong code for the administered drug is a claim integrity error and an audit risk. Check the unit definitions as well, because they are not identical across the three codes. A product with no specific code is reported under J3490 with a written description on the claim.

Common J0348 billing errors and how to avoid them

J0348 denials cluster around a predictable set of errors, and a pre-submission checklist prevents most of them. Build the checklist into the billing workflow rather than relying on memory, and first-pass denials fall away.

• Wrong unit count: billing 1 unit for a 100 mg dose instead of 100 units. Fix: confirm the 1 mg per unit rule on every J0348 claim.
• Missing or non-specific ICD-10: using B37.9 when B37.7 or B37.81 is available and documented. Fix: map the chart diagnosis to the most specific code before claim preparation.
• No prior authorization number: submitting to a payer that requires PA without the number in field 23 of the CMS-1500. Fix: verify PA status before administration.
• Missing or malformed NDC: omitting it on Medicaid claims, or formatting it as 10 digits instead of 11. Fix: record the NDC from the vial label at administration.
• Wrong claim form: using the CMS-1500 for a facility setting, or the UB-04 for a physician office. Fix: confirm the billing setting before submission.
• Missing waste modifiers: leaving off JW when part of a single-dose vial is discarded, or JZ when none is. Fix: check each payer’s modifier requirements quarterly.

How Pabau keeps J0348 documentation and claim units in step

In most practices the anidulafungin dose is recorded in one place and billed from another. A nurse writes 200 mg in the infusion note. A biller reads it later, converts it to units, and types the number into the claim. Every one of those hand-offs is a chance for 200 units to become 2.

Pabau closes that distance. The clinical record captures the dose, route, lot number, and NDC while the infusion is happening. The milligram total is stored once, so nobody re-reads it from a vial label. Claims management then pulls those stored values into a pre-filled submission for the biller to review.

The billing team still owns the claim, but it starts from the chart instead of from a transcription. For a practice running repeat courses of anidulafungin, that removes the transfer error behind most J-code unit denials. It also leaves an administration record an auditor can follow.

Keep drug documentation and claim units in step

Pabau’s clinical records capture the dose, route, lot number, and NDC at the point of care. Claims management then pulls those recorded values into a pre-filled submission, so the unit count matches the chart.

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Conclusion

J0348 rewards a workflow more than it rewards code knowledge. The unit rule takes one sentence to learn. It still fails on claims where the milligram total was read off a vial label instead of the administration record.

So decide where the unit count comes from, write that rule down, and hold it for every course of anidulafungin. Fix the source of the number and the rest of the checklist becomes routine. The diagnosis, the NDC, and the PA number are all in the chart already.

Book a demo to see how Pabau keeps drug administration records and J-code claim units aligned.

Continue your research

Need a framework for managing claim denials systematically? Denial management in healthcare covers the denial workflow stages and how to reduce repeat errors.

Want to know what makes a drug claim pass on first submission? Clean claim requirements sets out the fields payers check before they pay.

Want to understand the full claims submission process? Superbill fundamentals explains how billing data flows from the clinical encounter to the payer.

Billing a drug that has no specific J-code? HCPCS code J3490 explains how to report an unclassified drug without triggering a denial.

Looking for guidance on medical billing compliance for drug claims? Medical billing compliance outlines documentation and audit-readiness requirements for physician-administered drugs.

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