By Counterforce Health Team in Firdapse (amifampridine) —

Coding That Helps Get Firdapse (amifampridine) Covered by Humana in Pennsylvania: ICD-10, NDC, and Billing Requirements

Answer Box: Getting Firdapse (amifampridine) Covered by Humana in Pennsylvania

Quick approval path: Use ICD-10 codes G70.80 or G70.81 for Lambert-Eaton myasthenic syndrome (LEMS), bill with the correct Firdapse NDC (49948-100-01 for 10mg tablets), and submit via Medicare Part D pharmacy benefit—not Part B. Humana requires prior authorization with EMG and antibody test results. First step today: Verify your diagnosis documentation includes VGCC antibody results and EMG showing >100% CMAP increment, then have your prescriber submit PA through Humana's provider portal or fax 877-486-2621.

Table of Contents

  1. Coding Basics: Medical vs. Pharmacy Benefit Paths
  2. ICD-10 Mapping for LEMS
  3. Product Coding: NDC, HCPCS, and Units
  4. Clean Request Anatomy
  5. Frequent Coding Pitfalls
  6. Verification with Humana Resources
  7. Pre-Submission Audit Checklist
  8. Pennsylvania Appeals Process
  9. FAQ

Coding Basics: Medical vs. Pharmacy Benefit Paths

Firdapse (amifampridine) follows the pharmacy benefit pathway under Medicare Part D, not the medical benefit (Part B). This distinction affects everything from prior authorization requirements to billing codes.

Coverage at a Glance

Requirement Details Source
Benefit Type Medicare Part D (pharmacy) CMS Coverage Database
Prior Authorization Always required Humana PA Requirements
Formulary Tier Specialty/Tier 5 Humana Drug Guide
Billing Method NDC number on pharmacy claims Medicare Part D guidelines
HCPCS Code J8499 (if required by system) Billing guidance
Key Point: Never attempt to bill Firdapse under Medicare Part B as a provider-administered drug. It's self-administered and belongs under Part D pharmacy coverage.

ICD-10 Mapping for LEMS

Accurate diagnosis coding is critical for Firdapse approval. Use these primary codes for Lambert-Eaton myasthenic syndrome:

Primary ICD-10 Codes

  • G70.80: Lambert-Eaton syndrome, unspecified
  • G70.81: Other specified Lambert-Eaton syndrome (use when subtype is documented)

Documentation Words That Support Coding

Your medical records should include these key elements:

Clinical Features:

  • Progressive muscle weakness
  • Fluctuating muscle strength
  • Autonomic symptoms (dry mouth, constipation)
  • Post-exercise facilitation

Diagnostic Evidence:

  • EMG showing low compound muscle action potential (CMAP) amplitude at rest
  • >100% increment in CMAP amplitude after high-frequency stimulation
  • Positive voltage-gated calcium channel (VGCC) antibodies
  • Confirmation of LEMS diagnosis by neuromuscular specialist
Clinician Corner: Document whether LEMS is autoimmune (idiopathic) or paraneoplastic. Use G70.81 when the subtype is specified, as this provides stronger medical necessity support for Firdapse coverage.

Product Coding: NDC, HCPCS, and Units

NDC Numbers for Firdapse

The primary NDC for billing is:

  • 49948-100-01: Firdapse 10 mg tablets (verify current NDC with your pharmacy)

HCPCS/J-Code Requirements

  • Primary: Use NDC number for all pharmacy claims
  • If system requires HCPCS: J8499 ("prescription drug, oral, non-chemotherapeutic, not otherwise specified")

Units and Dosing Math

Firdapse dosing follows these parameters:

  • Starting dose: 15-30 mg daily (divided 3-5 times)
  • Maximum dose: 100 mg daily (10 tablets)
  • Billing units: 1 unit = 1 tablet (10 mg)

Example calculation for maximum dose:

  • 100 mg ÷ 10 mg per tablet = 10 tablets daily
  • Medicare billing: 10 units per day
  • Monthly supply: ~300 tablets (30-day supply)
Important: Always round to whole tablets for billing. Humana's quantity limits typically allow up to 240 tablets per 30 days, accommodating most therapeutic doses.

Clean Request Anatomy

Step-by-Step: Fastest Path to Approval

  1. Confirm Diagnosis (Prescriber)
    • Document LEMS with ICD-10 G70.80 or G70.81
    • Include EMG and VGCC antibody results
    • Timeline: Same day as patient visit
  2. Submit Prior Authorization (Prescriber/Staff)
    • Use Humana provider portal or fax 877-486-2621
    • Include clinical notes, lab results, prior therapy failures
    • Timeline: 24-48 hours to submit
  3. Track Approval Status (Patient/Prescriber)
    • Standard review: 30 days for Part C, 7 days for Part D
    • Expedited available for urgent cases (72 hours)
    • Check status via Humana member portal
  4. Fill Prescription (Patient)
    • Use specialty pharmacy if required
    • Verify NDC matches approved request
    • Timeline: 3-5 business days after approval

Required Documentation Checklist

  • Confirmed LEMS diagnosis by neuromuscular specialist
  • EMG results showing characteristic findings
  • VGCC antibody test results
  • Documentation of symptom severity and functional impact
  • Prior therapy trials and outcomes (if applicable)
  • Contraindication screening (seizure history, cardiac issues)

Frequent Coding Pitfalls

Common Mistakes and Fixes

Pitfall Fix Impact
Using wrong benefit (Part B vs Part D) Always bill under Part D pharmacy Automatic denial
Missing EMG documentation Include EMG with >100% CMAP increment Medical necessity denial
Incorrect NDC Verify 49948-100-01 for 10mg tablets Claim rejection
Exceeding dose limits Max 100mg daily (10 tablets) Quantity limit denial
Incomplete diagnosis code Use G70.80 or G70.81, not general myasthenia codes Prior auth rejection

Unit Conversion Errors

Correct calculation:

  • Patient prescribed 80 mg daily
  • 80 mg ÷ 10 mg per tablet = 8 tablets daily
  • Bill 8 units per day

Common error:

  • Billing in mg instead of tablets
  • Using compound unit calculations
  • Mixing tablet strengths in calculations

Verification with Humana Resources

Cross-Check Your Codes

Before submitting any claim or prior authorization:

  1. Verify Formulary Status
  2. Confirm NDC Accuracy
    • Match NDC to exact product dispensed
    • Verify with pharmacy before filling
    • Check for any NDC updates from manufacturer
  3. Review PA Requirements
    • Current clinical criteria at provider.humana.com
    • Required forms and documentation
    • Submission methods and timelines
Tip: Humana's provider services can verify coverage requirements before submission. Call the number on the member's insurance card for real-time verification.

Pre-Submission Audit Checklist

Use this checklist before submitting any Firdapse request to Humana:

Clinical Documentation

  • ICD-10 code (G70.80 or G70.81) matches diagnosis
  • EMG results show characteristic LEMS findings
  • VGCC antibody status documented
  • Neuromuscular specialist confirmation included

Coding Accuracy

  • Correct NDC number (49948-100-01 for 10mg)
  • Proper unit calculations (tablets, not mg)
  • Dose within FDA limits (≤100mg daily)
  • Part D benefit pathway selected

Administrative Requirements

  • Prior authorization submitted before dispensing
  • All required forms completed
  • Supporting documentation attached
  • Submission method confirmed (portal vs. fax)

Pennsylvania-Specific Considerations

  • Patient aware of state external review rights
  • Appeal timelines documented (4 months for external review)
  • Contact information for PA Insurance Department available

Pennsylvania Appeals Process

If Humana denies your Firdapse request, Pennsylvania offers robust appeal options with high success rates.

Internal Appeals Timeline

  1. Request internal review within 60 days of denial
  2. Standard review: 30 days for determination
  3. Expedited review: 72 hours for urgent cases
  4. Submit additional documentation during review period

Pennsylvania External Review

If internal appeals fail, Pennsylvania's Independent External Review Program provides a second chance:

  • Timeline: Request within 4 months of final internal denial
  • Process: Independent physicians review your case
  • Success rate: Approximately 50% of appeals are overturned
  • Binding decision: Humana must comply with favorable rulings

How to request external review:

  1. Complete internal appeals process first
  2. Submit request to Pennsylvania Insurance Department
  3. Include all medical records and prior authorization documentation
  4. Await assignment to independent review organization
Note: Pennsylvania's external review program has been particularly successful for specialty drug appeals, with many patients obtaining coverage for initially denied treatments.

FAQ

Q: How long does Humana prior authorization take for Firdapse in Pennsylvania? A: Standard reviews take up to 30 days for Medicare Advantage (Part C) and 7 days for Part D. Expedited reviews are completed within 72 hours for urgent cases.

Q: What if Firdapse is non-formulary on my Humana plan? A: You can request a formulary exception through the same prior authorization process. Include documentation showing medical necessity and why formulary alternatives aren't appropriate.

Q: Can I request an expedited appeal if my Firdapse is denied? A: Yes, if your condition poses an immediate health risk. Your prescriber must document the urgency and submit supporting clinical evidence.

Q: Does step therapy apply to Firdapse coverage? A: Humana may require documentation of prior therapy trials (pyridostigmine, IVIG, immunosuppressants) before approving Firdapse, depending on your specific plan.

Q: What's the difference between G70.80 and G70.81 for billing? A: Use G70.80 for unspecified LEMS and G70.81 when the subtype (autoimmune vs. paraneoplastic) is documented. G70.81 may provide stronger medical necessity support.

Q: Can I appeal to Pennsylvania if I have Medicare Advantage through Humana? A: Medicare Advantage appeals follow federal Medicare rules first, but Pennsylvania's consumer protection laws may provide additional rights. Contact the PA Insurance Department for guidance on your specific situation.

Counterforce Health specializes in turning insurance denials into successful appeals by analyzing denial letters, plan policies, and clinical documentation to craft targeted, evidence-backed responses. Our platform helps patients, clinicians, and specialty pharmacies navigate complex prior authorization requirements and appeals processes for specialty medications like Firdapse.

For immediate assistance with Firdapse denials or appeals in Pennsylvania, consider working with coverage advocates who understand both Humana's specific requirements and Pennsylvania's appeals landscape. The combination of proper coding, complete documentation, and strategic appeal timing significantly improves approval rates for this essential LEMS treatment.

Sources & Further Reading

Disclaimer: This information is for educational purposes only and does not constitute medical or legal advice. Always consult with your healthcare provider and insurance plan for specific coverage decisions. Coverage policies and requirements may change; verify current information with official sources before making healthcare decisions.

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