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

How to Get Enhertu (fam-trastuzumab deruxtecan-nxki) Covered by Aetna CVS Health in New York: Prior Authorization Guide and Appeals Process

Quick Answer: Getting Enhertu Covered by Aetna in New York

Getting Enhertu (fam-trastuzumab deruxtecan-nxki) approved by Aetna CVS Health requires prior authorization for all plans. Call (866) 752-7021 or fax (888) 267-3277 to start. You'll need HER2 pathology reports, prior therapy documentation, and a medical necessity letter with ILD risk mitigation plan. Standard decisions take 30-45 days; expedited reviews are completed within 72 hours. If denied, you can appeal within 180 days and pursue New York's external review through DFS with binding decisions. First step today: Contact your oncologist to gather HER2 test results and prior treatment records.

Table of Contents

  1. Prior Authorization Requirements
  2. Clinical Documentation Checklist
  3. Formulary Status and Costs
  4. Step-by-Step: Fastest Path to Approval
  5. Common Denial Reasons & Solutions
  6. Appeals Process in New York
  7. Cost-Saving Options
  8. When to Escalate
  9. FAQ

Prior Authorization Requirements

Enhertu requires precertification for all Aetna plans per Clinical Policy Bulletin 0966. This high-cost specialty oncology drug undergoes rigorous review before approval.

Coverage at a Glance

Requirement What It Means Where to Find It Timeline
Prior Authorization Required for all plans Aetna Precert List 30-45 days standard
HER2 Testing Must confirm HER2 status Pathology report Before PA submission
Prior Therapy Document previous treatments Medical records Include failures/intolerance
ILD Risk Plan Lung toxicity monitoring Medical necessity letter Required for approval
Specialty Pharmacy CVS Specialty typically required Plan documents After approval

FDA-Approved Indications

Prior authorization approval requires documentation that matches an FDA-approved indication:

  • 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)
  • HER2-positive solid tumors (tumor-agnostic, after prior therapy)

Clinical Documentation Checklist

Your authorization request must include comprehensive clinical evidence. Missing documentation is the most common cause of delays.

Required Documents

HER2 Pathology Report

  • Confirm HER2 status (IHC 3+ or ISH amplified for HER2-positive; IHC 1+ or 2+ for HER2-low)
  • Include testing methodology and laboratory details
  • Ensure report is recent and matches current diagnosis

Prior Therapy Documentation

  • Specific drug names, dosing, and treatment duration
  • Documented reason for discontinuation (progression, intolerance, contraindication)
  • Response assessment and imaging reports where applicable

Medical Necessity Letter Requirements

  • Patient identification and clinical indication
  • Why alternatives are inappropriate or have failed
  • ILD risk mitigation plan with baseline pulmonary assessment
  • Scheduled monitoring protocols for interstitial lung disease
  • Correct ICD-10 and HCPCS codes (J9358 for billing)
Clinician Corner: The medical necessity letter should address why standard alternatives like trastuzumab/pertuzumab, T-DM1, or tucatinib regimens are not appropriate. Include specific clinical factors such as cardiac contraindications, prior resistance, or disease progression on standard therapies.

Formulary Status and Costs

Enhertu is typically non-formulary or high-tier specialty on Aetna plans. Understanding your benefit structure helps set expectations for out-of-pocket costs.

What Drives Your Costs

Benefit Design Factors:

  • Formulary tier placement (usually specialty tier 4-5)
  • Annual deductible requirements
  • Coinsurance percentages (often 20-40% for specialty drugs)
  • Out-of-pocket maximums

Pricing Context:

  • Approximate cost: $2,440 per 100mg vial
  • Weight-based dosing every 3 weeks
  • Multiple vials may be needed per cycle

Benefit Investigation

Contact Aetna member services at the number on your ID card to confirm:

  • Exact formulary tier for Enhertu
  • Whether your deductible applies
  • Coinsurance percentage
  • Specialty pharmacy requirements

Information to Record:

  • Reference number for your call
  • Representative's name
  • Specific benefit details provided
  • Any prior authorization requirements mentioned

Step-by-Step: Fastest Path to Approval

1. Gather Clinical Documentation (Patient + Oncologist)

Timeline: 1-2 weeks

  • Request HER2 pathology reports from all relevant biopsies
  • Compile complete treatment history with dates and outcomes
  • Schedule baseline pulmonary function tests if not recent

2. Submit Prior Authorization Request (Oncologist's Office)

Contact: (866) 752-7021 or fax (888) 267-3277 Timeline: Same day submission possible

3. Follow Up on Decision (Patient + Clinic Staff)

Timeline: 30-45 days standard, 72 hours expedited

  • Track submission with reference number
  • Contact Aetna if no response within expected timeframe
  • Prepare appeal documentation if needed

4. Coordinate Specialty Pharmacy (If Approved)

Timeline: 1-2 weeks

  • Enroll with CVS Specialty Pharmacy
  • Confirm insurance coverage transfer
  • Schedule first infusion appointment

5. Appeal If Denied (Patient + Oncologist)

Timeline: Must start within 180 days of denial

  • Review denial letter for specific reasons
  • Gather additional supporting evidence
  • Submit internal appeal first, then external review if needed

Common Denial Reasons & Solutions

Denial Reason How to Overturn Required Documentation
"Not medically necessary" Demonstrate FDA indication match Updated pathology, treatment history
"Experimental/investigational" Cite FDA approval and guidelines FDA label, NCCN guidelines
Missing HER2 status Submit complete pathology report IHC/ISH results with methodology
Inadequate prior therapy Document specific failures/intolerance Treatment records, imaging, toxicity reports
ILD risk concerns Provide comprehensive monitoring plan Pulmonary function tests, monitoring protocol
Step therapy required Request exception with clinical justification Medical necessity letter, contraindication documentation

Appeals Process in New York

New York provides robust patient protections for insurance denials, with multiple levels of review and binding external decisions.

Internal Appeals with Aetna

Timeline: Must file within 180 days of denial Process:

  • Submit written appeal with additional clinical evidence
  • Standard review: 30 days
  • Expedited review: 72 hours for urgent cases
  • Include peer-reviewed literature supporting Enhertu use

New York External Review

After completing Aetna's internal appeal process, you can request external review through the New York Department of Financial Services (DFS).

Key Benefits:

  • Independent medical experts review your case
  • Binding decisions on the insurer
  • Fast timelines: 72 hours for drug appeals, 24 hours for urgent cases
  • Low cost: Maximum $25 fee, waived for financial hardship

How to File:

  1. Complete Aetna's internal appeal first
  2. Submit external review request within 4 months of final internal denial
  3. Use DFS online portal or mail forms
  4. Include all medical records and denial correspondence
From Our Advocates: We've seen cases where patients initially denied Enhertu for "experimental" reasons succeeded on external review by submitting comprehensive FDA labeling documentation and peer-reviewed efficacy studies. The key was demonstrating that the indication was FDA-approved and supported by clinical guidelines, not experimental.

Cost-Saving Options

Manufacturer Copay Programs

The Enhertu Patient Savings Program offers significant cost reduction for eligible patients:

Eligibility:

  • Commercial insurance that covers Enhertu
  • Not eligible: Medicare, Medicaid, or government insurance
  • No income requirements

Benefits:

  • Pay as little as $0 per year out-of-pocket
  • Up to $100 per infusion for administration costs
  • Excludes Massachusetts and Rhode Island residents for infusion assistance

How to Enroll:

Alternative Financial Assistance

For patients ineligible for copay cards:

  • Patient assistance programs for uninsured/underinsured patients
  • Foundation grants through organizations like CancerCare
  • Hospital financial assistance programs
  • State pharmaceutical assistance programs

Specialty Pharmacy Coordination

CVS Specialty Requirements:

  • Most Aetna plans require CVS Specialty for Enhertu dispensing
  • Enrollment typically required after prior authorization approval
  • Coordinate with oncology practice for seamless transition
  • Request exceptions if CVS cannot meet clinical needs

When to Escalate

Contact New York regulators if you experience:

  • Missed deadlines by Aetna beyond required timeframes
  • Excessive documentation requests that seem unreasonable
  • Coverage decisions that appear to violate state insurance laws
  • Access barriers that delay medically necessary treatment

New York Department of Financial Services

  • Consumer Hotline: 1-800-342-3736
  • Online complaints: DFS website
  • Community Health Advocates (free assistance): 888-614-5400

Counterforce Health specializes in turning insurance denials into targeted, evidence-backed appeals. The platform analyzes denial letters, plan policies, and clinical notes to identify the specific denial basis and draft point-by-point rebuttals aligned to the plan's own rules, pulling the right medical evidence and weaving it into appeals that meet procedural requirements.

Frequently Asked Questions

How long does Aetna prior authorization take for Enhertu in New York? Standard prior authorization decisions are made within 30-45 days. Expedited reviews for urgent cases are completed within 72 hours.

What if Enhertu is non-formulary on my Aetna plan? You can request a formulary exception with your prescriber's supporting medical statement. Aetna must respond within 72 hours (24 hours for expedited requests).

Can I request an expedited appeal in New York? Yes, both Aetna's internal appeals and New York's external review offer expedited timelines when delay could harm your health. Drug appeals through DFS are decided within 72 hours standard, 24 hours urgent.

Does step therapy apply if I've failed treatments outside New York? Yes, documented treatment failures from any location count toward meeting step therapy requirements, as long as you have proper medical records.

What happens if Aetna approves Enhertu but my costs are still too high? Explore the manufacturer copay program, request a formulary tier exception, or apply for foundation grants. Counterforce Health can also help navigate cost-related appeals.

How do I prove medical necessity for Enhertu? Medical necessity requires demonstrating FDA-approved indication match, appropriate HER2 testing, documented prior therapy failures or contraindications, and a comprehensive ILD monitoring plan.

Can my oncologist request a peer-to-peer review? Yes, oncologists can request peer-to-peer reviews with Aetna medical directors to discuss clinical rationale directly. This often resolves complex cases more efficiently than written appeals alone.

Sources & Further Reading

Disclaimer: This information is for educational purposes only and does not constitute medical or legal advice. Insurance coverage decisions depend on individual plan benefits, clinical circumstances, and current policies. Always consult with your healthcare provider and insurance plan directly for coverage determinations. For personalized assistance with insurance appeals, consider consulting with patient advocacy organizations or services like Counterforce Health that specialize in evidence-based coverage appeals.

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