By Counterforce Health Team in Strimvelis (autologous CD34+ ADA-SCID gene therapy) —

Getting Strimvelis Gene Therapy Covered by Humana in California: Complete Requirements Checklist and Appeals Guide

Answer Box: Fast Track to Coverage

Strimvelis is not FDA-approved in the U.S. and only available at SR-TIGET in Milan, Italy. Humana Medicare doesn't cover international medical tourism or non-emergency overseas treatments. However, you can still pursue coverage through these steps:

  1. Submit a prior authorization request with comprehensive ADA-SCID documentation and genetic testing results
  2. Request an exception for international treatment based on medical necessity and lack of U.S. alternatives
  3. If denied, file a California Independent Medical Review (IMR) through the DMHC within 180 days

Success depends on strong clinical documentation and California's robust patient appeal rights. Start by gathering genetic test results confirming ADA deficiency and specialist letters supporting medical necessity.

Table of Contents

  1. Who Should Use This Guide
  2. Member & Plan Basics
  3. Clinical Criteria Requirements
  4. Coding and Documentation
  5. Documentation Packet Essentials
  6. Submission Process
  7. International Coverage Challenges
  8. After Submission: What to Expect
  9. Denial Prevention Tips
  10. California Appeals Process
  11. Printable Requirements Checklist
  12. FAQ

Who Should Use This Guide

This checklist is designed for families of children with ADA-SCID (Adenosine Deaminase Severe Combined Immunodeficiency) who have Humana coverage in California and are considering Strimvelis gene therapy at SR-TIGET in Milan, Italy.

You'll need this guide if:

  • Your child has confirmed ADA-SCID with genetic testing
  • Standard treatments (enzyme replacement, stem cell transplant) aren't viable options
  • You're exploring Strimvelis as a potential treatment
  • You need to navigate Humana's prior authorization process

Expected outcome: While Humana doesn't typically cover international treatments, California's strong patient protection laws provide appeal pathways that have succeeded for other rare disease therapies when medical necessity is clearly established.

Member & Plan Basics

Coverage Requirements

  • Active Humana coverage with current member ID
  • Plan type verification (Medicare Advantage plans have different international coverage rules than commercial plans)
  • Deductible status - high-cost therapies may trigger annual limits
  • Prior authorization required for all gene therapies under Humana's 2025 Part B step therapy policy

International Treatment Limitations

Humana Medicare does not cover planned international treatments, including medical tourism to facilities like SR-TIGET. Coverage is limited to emergency care abroad only.

Clinical Criteria Requirements

Diagnosis Confirmation

Essential requirements for ADA-SCID diagnosis:

  • ADA enzyme activity <1% of normal levels in red blood cells
  • Genetic testing confirming biallelic pathogenic variants in the ADA gene
  • Clinical presentation consistent with SCID (recurrent severe infections, failure to thrive, absent T-cell immunity)
  • Specialist evaluation by pediatric immunologist or geneticist

Step Therapy Considerations

Document previous treatments attempted:

  • Enzyme replacement therapy (PEG-ADA) - results and any limitations
  • Hematopoietic stem cell transplantation evaluation - why not suitable (no matched donor, contraindications)
  • Supportive care measures tried and outcomes
Clinical Note: ADA-SCID is life-threatening in infancy. Current guidelines emphasize early definitive treatment, making delay for step therapy potentially harmful.

Coding and Documentation

Diagnosis Codes

  • Primary ICD-10: D81.3 (Adenosine deaminase deficiency)
  • Secondary codes: Z87.891 (Personal history of nicotine dependence), as clinically appropriate

Billing Considerations

Important: Strimvelis has no assigned HCPCS J-code for U.S. billing and is not covered under Medicare NCDs or LCDs. Any coverage would require individual case review and exception processes.

Documentation Packet Essentials

Medical Necessity Letter Components

Your specialist should include these elements in the prior authorization letter:

Patient Summary:

  • Age, weight, clinical presentation
  • Date of ADA-SCID diagnosis
  • Current clinical status and prognosis

Laboratory Evidence:

  • ADA enzyme activity results (specific numerical values)
  • Genetic testing report with identified mutations
  • Immunological studies (lymphocyte subsets, immunoglobulin levels)

Treatment Rationale:

  • Why standard treatments aren't suitable
  • Medical necessity for gene therapy approach
  • Specific rationale for Strimvelis vs. alternatives
  • Expected outcomes and monitoring plan

Supporting Documentation:

  • Recent clinic notes from immunologist/geneticist
  • Laboratory reports and imaging studies
  • Previous treatment records and responses
  • Literature supporting Strimvelis efficacy for ADA-SCID

Required Attachments

  • Complete genetic testing report
  • ADA enzyme activity results
  • Specialist consultation notes
  • Previous treatment documentation
  • Clinical photographs or imaging (if relevant)

Submission Process

Prior Authorization Submission

  1. Complete Humana's prior authorization form (verify current version on Humana provider portal)
  2. Submit via provider portal or fax (confirm current submission method)
  3. Include all required documentation in initial submission to avoid delays
  4. Request expedited review if clinically urgent

Timeline Expectations

  • Standard review: 30 days for Part C decisions
  • Expedited review: 72 hours for urgent cases
  • Appeals: 65 days from denial for Medicare appeals
Tip: Submit complete documentation initially. Incomplete submissions reset the review timeline.

International Coverage Challenges

Humana's International Policy

Humana Medicare explicitly excludes coverage for:

  • Planned international treatments
  • Medical tourism
  • Non-emergency overseas care

Exception Request Strategy

To request an exception for international treatment:

  1. Document lack of U.S. alternatives - Strimvelis is only available at SR-TIGET
  2. Establish medical necessity - why this specific treatment is required
  3. Provide cost-effectiveness analysis - compare to ongoing supportive care costs
  4. Include specialist letter supporting international treatment necessity

After Submission: What to Expect

Tracking Your Request

  • Save confirmation numbers from all submissions
  • Check status weekly through Humana member portal
  • Document all communications with dates and representative names
  • Maintain copies of all submitted materials

Likely Outcomes

Initial denial is expected due to international treatment exclusions. This sets up the appeals process where California's patient protection laws become crucial.

Denial Prevention Tips

Five Common Pitfalls to Avoid

  1. Incomplete genetic documentation - Ensure both enzyme and genetic testing results are included
  2. Missing specialist evaluation - Primary care physician letters insufficient for rare disease coverage
  3. Inadequate step therapy documentation - Must show why standard treatments aren't viable
  4. Incorrect forms - Use current Humana prior authorization forms only
  5. Timeline violations - Submit appeals within required deadlines

California Appeals Process

California offers some of the strongest patient appeal rights in the nation through the Department of Managed Health Care (DMHC).

Internal Appeal Process

  1. File internal appeal with Humana within 180 days of denial
  2. Include additional documentation addressing denial reasons
  3. Request expedited review if medically urgent
  4. Wait up to 30 days for Humana's response

Independent Medical Review (IMR)

If Humana upholds the denial:

  1. File IMR application through DMHC website
  2. No cost to patient - DMHC covers review expenses
  3. Independent physician review by specialists in relevant field
  4. Binding decision - Humana must comply if IMR approves coverage
  5. Timeline: 30-45 days standard, 72 hours expedited
Success Rate: California IMRs have high success rates for well-documented, medically necessary rare disease treatments.

DMHC Help Center

Call 888-466-2219 for assistance with:

  • Filing complaints or IMRs
  • Understanding your appeal rights
  • Navigating the process

At Counterforce Health, we specialize in turning insurance denials into successful appeals by creating evidence-backed, payer-specific documentation. Our platform helps families navigate complex prior authorization requirements and builds compelling cases for rare disease treatments like gene therapies. When facing coverage challenges for innovative treatments, having the right documentation strategy can make the difference between denial and approval.

Printable Requirements Checklist

Before Submitting:

  • Active Humana coverage verified
  • ADA enzyme activity <1% documented
  • Genetic testing confirming ADA mutations
  • Specialist evaluation completed
  • Previous treatments documented
  • Medical necessity letter prepared
  • All lab reports included
  • Current prior authorization form used

After Denial:

  • Internal appeal filed within 180 days
  • Additional documentation submitted
  • IMR application prepared if needed
  • DMHC contact information saved
  • All deadlines tracked

FAQ

How long does Humana prior authorization take in California? Standard reviews take up to 30 days, expedited reviews 72 hours. International treatment requests may take longer due to additional review requirements.

What if Strimvelis is considered experimental? Document FDA breakthrough therapy designation for similar gene therapies and EMA approval for Strimvelis. Include peer-reviewed literature supporting efficacy.

Can I request an expedited appeal? Yes, if the delay would seriously jeopardize your child's health. Include physician documentation of urgency.

Does step therapy apply to gene therapies? Humana's 2025 step therapy policy may require documentation of previous treatment failures.

What counts as medical necessity for Strimvelis? Confirmed ADA-SCID diagnosis, failure/unsuitability of standard treatments, and specialist recommendation for gene therapy approach.

How much does treatment cost? Strimvelis has a list price of approximately €594,000 (about $650,000) per treatment, administered as a one-time therapy.

What if I have other insurance besides Humana? Coordinate benefits carefully. Secondary insurance may have different international coverage policies.

Can I appeal to external reviewers? Yes, California's IMR process provides binding external review through independent medical experts.

Disclaimer: This guide is for informational purposes only and does not constitute medical or legal advice. Coverage decisions depend on individual circumstances, plan terms, and clinical factors. Always consult with your healthcare providers and insurance representatives for personalized guidance. For additional help with insurance appeals in California, contact the DMHC Help Center at 888-466-2219.

The team at Counterforce Health understands that navigating insurance coverage for rare disease treatments can feel overwhelming. We're here to help families build stronger cases for coverage by identifying the specific evidence and documentation that payers require for complex therapies like gene treatments.

Sources & Further Reading

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