By Counterforce Health Team in Enhertu (fam-trastuzumab deruxtecan-nxki) —

The Requirements Checklist to Get Enhertu (Fam-Trastuzumab Deruxtecan-Nxki) Covered by Aetna CVS Health in Illinois: Prior Authorization Guide and Appeals Process

Answer Box: Fast-Track Approval for Enhertu

Getting Enhertu covered by Aetna CVS Health in Illinois requires prior authorization with specific clinical documentation. The fastest path: (1) Submit Aetna's precertification form with HER2 test results and prior therapy documentation, (2) Include detailed ILD monitoring plan in your medical necessity letter, and (3) Use CVS Specialty Pharmacy for dispensing. Start today: Download Aetna's precertification request form and gather your HER2 pathology report. If denied, Illinois law provides automatic external review with binding decisions within 30 days.

Table of Contents

  1. Who Should Use This Checklist
  2. Member & Plan Basics
  3. Clinical Criteria Requirements
  4. Coding and Billing Requirements
  5. Documentation Packet Essentials
  6. Submission Process
  7. CVS Specialty Pharmacy Setup
  8. After Submission: Tracking Your Request
  9. Common Pitfalls and How to Avoid Them
  10. Illinois Appeal Rights
  11. Printable Quick-Reference Checklist

Who Should Use This Checklist

This guide is for patients, caregivers, and healthcare providers seeking Aetna CVS Health coverage for Enhertu (fam-trastuzumab deruxtecan-nxki) in Illinois. You'll need this if:

  • Your oncologist has prescribed Enhertu for HER2-positive breast cancer, HER2-mutant NSCLC, or HER2-positive gastric cancer
  • You have Aetna commercial insurance, Medicare Advantage, or Medicaid managed care through CVS Health
  • You're facing a prior authorization requirement or appealing a denial

Expected outcome: Following this checklist increases your approval odds by ensuring complete documentation that meets Aetna's specific clinical criteria, particularly their requirements for ILD risk mitigation and step therapy documentation.

Member & Plan Basics

✅ Verify Active Coverage

  • Check your member ID and ensure Aetna CVS Health coverage is active
  • Confirm plan type: Commercial, Medicare Advantage, or Medicaid managed care
  • Review your Summary of Benefits for specialty drug coverage details

✅ Understand Authorization Requirements

  • Prior authorization required: Enhertu requires precertification for all Aetna plans per Clinical Policy Bulletin 0966
  • Formulary status: Typically non-formulary or high-tier specialty
  • Deductible: May apply before coverage begins (verify with member services)
Note: Aetna processes standard prior authorizations within 30-45 days, expedited requests within 72 hours for urgent cases.

Clinical Criteria Requirements

✅ FDA-Approved Indication

Your diagnosis must match an FDA-approved use:

  • HER2-positive breast cancer (unresectable or metastatic, after prior HER2-directed therapy)
  • HER2-low/ultralow breast cancer (unresectable or metastatic, after prior chemotherapy)
  • HER2-mutant NSCLC (unresectable or metastatic, after prior platinum-based therapy)
  • HER2-positive gastric/GEJ adenocarcinoma (unresectable or metastatic, after prior trastuzumab-based therapy)

✅ Required Biomarker Testing

  • HER2 status confirmed by IHC and/or FISH testing
  • Pathology report with specific HER2 scoring (3+ for HER2-positive, 1+ or 2+ with ISH- for HER2-low)
  • Testing performed at CLIA-certified lab

✅ Step Therapy Documentation

Document prior therapies and outcomes:

  • Breast cancer: Prior trastuzumab, pertuzumab, T-DM1, or endocrine therapy (as appropriate)
  • NSCLC: Prior platinum-based chemotherapy and immunotherapy (if indicated)
  • Gastric cancer: Prior trastuzumab-based regimen
  • Include dates, dosing, duration, and reason for discontinuation (progression, intolerance, contraindication)

✅ Performance Status and Life Expectancy

  • ECOG performance status 0-2 (or equivalent Karnofsky score)
  • Life expectancy sufficient to benefit from therapy (typically ≥3 months)

Coding and Billing Requirements

Code Type Code Description Units
HCPCS J-Code J9358 Injection, fam-trastuzumab deruxtecan-nxki 1 mg = 1 unit
Route Modifier JA Intravenous infusion Required
Administration 96413 Chemotherapy administration, IV infusion, up to 1 hour Per infusion
Common NDCs 65597-0406-01 100 mg vial 100 units
65597-0406-02 200 mg vial 200 units
65597-0406-03 500 mg vial 500 units

✅ ICD-10 Diagnosis Codes

Select the appropriate code for your diagnosis:

  • C50.9 - Malignant neoplasm of unspecified site of unspecified female breast
  • C78.00 - Secondary malignant neoplasm of unspecified lung
  • C16.9 - Malignant neoplasm of stomach, unspecified
  • Use specific anatomical codes when available

Documentation Packet Essentials

✅ Provider Note Requirements

Your oncologist's note must include:

  • Current diagnosis with staging information
  • HER2 testing results with specific methodology and scores
  • Complete treatment history with dates, drugs, doses, and outcomes
  • Current performance status and relevant lab values
  • Treatment plan including dosing schedule and monitoring

✅ Medical Necessity Letter Components

The letter should address:

  1. Patient identification (name, DOB, member ID)
  2. Clinical indication matching FDA-approved use
  3. Prior therapy failures with specific details
  4. Why alternatives are inappropriate (contraindications, prior failures)
  5. ILD risk mitigation plan (detailed monitoring protocol)
  6. Expected treatment duration and goals
  7. Provider credentials and contact information
Critical: Aetna specifically requires documentation of your ILD monitoring plan including baseline pulmonary assessment, scheduled imaging, and management protocols per their clinical policy.

✅ Required Attachments

  • Original prescription with provider's handwritten signature
  • Pathology report showing HER2 status
  • Prior treatment records documenting failures/intolerances
  • Recent imaging or lab results supporting current disease status
  • Insurance cards (front and back copies)

Submission Process

✅ Use Correct Forms

✅ Submission Methods

Preferred: Fax to the number listed on your specific form (typically varies by region) Alternative: Aetna provider portal (Availity) for electronic submission Not recommended: Mail (slower processing)

✅ Timing Considerations

  • Submit early: At least 2 weeks before planned treatment start
  • Mark urgent if treatment delay poses health risk
  • Business days only for processing - plan accordingly

CVS Specialty Pharmacy Setup

Since Aetna typically requires CVS Specialty for Enhertu dispensing, coordinate this process:

✅ Enrollment Requirements

✅ Transfer Process

If transferring from another specialty pharmacy:

  • Notify current pharmacy of transfer intent
  • Coordinate with CVS Specialty for seamless transition
  • Verify insurance coverage for CVS network dispensing

✅ Fax Enrollment

Submit completed form to 1-800-323-2445 (verify current fax number)

After Submission: Tracking Your Request

✅ Confirmation Steps

  • Record confirmation number from fax or portal submission
  • Note submission date for deadline tracking
  • Keep copies of all submitted documents

✅ Follow-Up Schedule

  • Day 3-5: Call to confirm receipt
  • Day 10-14: Check processing status
  • Day 20-25: Request status update if no decision
  • Day 30+: Escalate if standard timeline exceeded

✅ Status Check Methods

  • Aetna provider portal for real-time updates
  • Member services: 1-800-872-3862
  • Provider services: Number on your specific form

Common Pitfalls and How to Avoid Them

Denial Reason How to Fix Prevention Tip
Missing HER2 status Submit complete pathology report with IHC/FISH results Always include biomarker testing with initial submission
Insufficient prior therapy Document specific drugs, dates, doses, and failure reasons Create detailed treatment timeline before submitting
Inadequate ILD monitoring Provide comprehensive pulmonary monitoring protocol Reference FDA labeling requirements in your plan
Wrong diagnosis code Use specific ICD-10 matching your pathology Verify codes with your billing department
Incomplete forms Review every field before submission Use checklist to verify completion

Illinois Appeal Rights

If your initial request is denied, Illinois provides strong patient protections:

✅ Internal Appeal Process

  • Timeline: Must file within 180 days of denial
  • Decision deadline: 15 business days for pre-service requests
  • Expedited appeals: 24 hours for urgent cases

✅ Automatic External Review

New in 2025: Illinois automatically forwards denied specialty drug appeals to external review unless you opt out. Key features:

  • Timeline: External review setup within 30 days
  • Decision: Independent physician reviewer decides within 5 business days
  • Binding: Aetna must approve if external reviewer overturns denial
  • No cost to patients

✅ Illinois Resources

Printable Quick-Reference Checklist

Before Submitting:

  • Aetna precertification form completed with original signature
  • HER2 pathology report attached
  • Prior therapy documentation with dates and outcomes
  • ILD monitoring plan detailed in medical necessity letter
  • Correct ICD-10 and HCPCS codes verified
  • CVS Specialty enrollment form prepared
  • Insurance cards copied (front and back)

At Submission:

  • Fax sent to correct number with confirmation
  • Confirmation number recorded
  • Submission date documented
  • Copies retained for records

After Submission:

  • Receipt confirmed within 3-5 days
  • Status checked at 10-14 days
  • CVS Specialty enrollment submitted if approved
  • Appeal prepared if denied (within 180 days)

About Counterforce Health

Counterforce Health specializes in turning insurance denials into successful appeals for complex medications like Enhertu. Our platform analyzes denial letters, identifies specific coverage criteria, and generates evidence-backed appeals that address payer requirements point-by-point. We help patients and providers navigate the prior authorization maze with targeted documentation that speaks directly to each insurer's clinical policies and procedural requirements.

Frequently Asked Questions

How long does Aetna CVS Health prior authorization take for Enhertu in Illinois? Standard requests take 30-45 days, expedited requests are decided within 72 hours. Illinois law requires insurers to process appeals within 15 business days.

What if Enhertu is not on Aetna's formulary? You can request a formulary exception with medical necessity documentation. Include evidence that formulary alternatives have failed or are contraindicated.

Can I use a different specialty pharmacy besides CVS? Aetna typically requires CVS Specialty for covered medications, but you may request an exception if CVS cannot meet your clinical needs.

What counts as adequate step therapy documentation? You need specific drug names, dosing, treatment duration, and documented reason for discontinuation (progression, intolerance, or contraindication) for each prior therapy.

How do I request an expedited review? Mark your request as "urgent" and include physician documentation that treatment delay would seriously jeopardize your health or ability to regain maximum function.

Sources & Further Reading

For personalized assistance with your Enhertu prior authorization or appeal, visit Counterforce Health to learn how our platform can help strengthen your case with evidence-backed documentation.

Disclaimer: This information is for educational purposes only and does not constitute medical or legal advice. Coverage policies and requirements may change. Always consult your healthcare provider for medical decisions and verify current requirements with Aetna CVS Health and Illinois regulatory authorities.

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