By Counterforce Health Team in Keytruda (pembrolizumab) —

How to Get Keytruda (Pembrolizumab) Covered by Aetna in California: Complete Guide with Forms and Appeal Scripts

Answer Box: To get Keytruda (pembrolizumab) covered by Aetna in California: (1) Submit prior authorization with PD-L1 test results and complete clinical documentation via Aetna's provider portal or fax 1-888-267-3277, (2) If denied, request peer-to-peer review within 14 days, then file internal appeal, (3) Use California's Independent Medical Review (IMR) through DMHC for external appeal—oncology specialty drug denials are overturned 68.6% of the time. Start with your oncologist gathering biomarker test results today.

Table of Contents

Coverage Requirements at a Glance

Requirement What It Means Where to Find It Source
Prior Authorization Required for all Keytruda prescriptions Aetna Precertification List Aetna 2025 PA List
PD-L1 Testing Must document CPS score for applicable indications FDA labeling requirements FDA Keytruda Label
Specialty Tier High cost-sharing, specialty pharmacy required CVS Caremark formulary Aetna Drug Guide
Step Therapy May require trying alternatives first Plan-specific PA criteria Aetna Clinical Policy
Appeals Deadline 180 days for internal, 6 months for IMR California regulations DMHC Guidelines

Step-by-Step: Fastest Path to Approval

1. Gather Required Documentation

Who: Your oncologist's office
Timeline: 1-2 weeks before treatment start
Documents needed:

  • Complete pathology report with cancer staging
  • PD-L1 immunohistochemistry results with CPS score
  • Prior treatment records showing failures/intolerances
  • Current labs and imaging showing disease status

2. Submit Prior Authorization

Who: Healthcare provider
Method: Aetna Provider Portal or fax 1-888-267-3277
Form: Keytruda Precertification Request
Timeline: Submit 7-10 days before planned treatment

3. Await Decision

Standard timeline: 30-45 days for non-urgent requests
Expedited: 72 hours for urgent cancer cases
Track status: Via Aetna provider portal or member services

4. If Approved

Treatment can begin immediately. Authorization typically valid for 6-12 months with periodic reviews.

5. If Denied

Move immediately to appeals process (see section below).

Tip: California patients have strong appeal rights. Don't give up after the first denial—specialty cancer drugs like Keytruda have high overturn rates in California's Independent Medical Review process.

Common Denial Reasons & How to Fix Them

Denial Reason How to Overturn Required Documentation
"No PD-L1 testing documented" Submit immunohistochemistry report Lab report with CPS score from FDA-approved test
"Step therapy not completed" Request medical exception Letter documenting contraindications to preferred drugs
"Not FDA-approved indication" Clarify diagnosis and staging Updated pathology confirming FDA-approved tumor type
"Experimental/investigational" Provide FDA approval evidence Current FDA labeling and approval date
"Not medically necessary" Submit comprehensive clinical rationale Complete medical necessity letter (see checklist below)

Appeals Playbook for California

Level 1: Peer-to-Peer Review

Timeline: Request within 14 days of denial
Process: Your oncologist discusses case directly with Aetna medical director
Preparation: Have clinical records, guidelines, and treatment rationale ready

Script for requesting peer-to-peer: "I'm calling to request a peer-to-peer review for [patient name] regarding the Keytruda denial. The patient has [specific cancer diagnosis] with [biomarker status] and meets FDA criteria. When can we schedule the clinical discussion?"

Level 2: Internal Appeal

Timeline: 180 days from denial date
Method: Written appeal with supporting documentation
Decision timeframe: 30 days standard, 72 hours expedited

Level 3: California Independent Medical Review (IMR)

Who handles: Department of Managed Health Care (DMHC)
Success rate: 68.6% overturn rate for oncology specialty drugs with Aetna
Timeline: 45 days standard, 7 days expedited
Cost: Free to patients
How to file: DMHC IMR Application

From our advocates: We've seen patients succeed in California IMR even after multiple internal denials. One case involved a patient whose Keytruda was initially denied as "not medically necessary" for a rare tumor type. The IMR reviewers, who were independent oncology specialists, overturned the denial within 30 days after reviewing the FDA labeling and clinical guidelines. The key was submitting complete biomarker testing and a detailed timeline of prior treatment failures.

Medical Necessity Letter Checklist

Your oncologist should include these elements:

Patient Information

  • Full name, DOB, member ID
  • Primary diagnosis with ICD-10 code
  • Cancer stage and histology
  • Performance status

Clinical Rationale

  • FDA-approved indication citation
  • PD-L1 CPS score and testing method
  • Prior treatments attempted and outcomes
  • Contraindications to alternative therapies
  • Expected treatment goals and monitoring plan

Supporting Evidence

  • Relevant clinical trial data
  • Professional guidelines (NCCN, ASCO)
  • FDA prescribing information excerpts
  • Pathology and lab reports attached

Scripts for Patients and Providers

Patient Script for Aetna Customer Service

"My oncologist prescribed Keytruda for my [cancer type], but it was denied. I'd like to understand the specific reasons and start the appeal process. Can you send me the detailed denial letter and explain my appeal options in California?"

Provider Script for Expedited Review

"This is Dr. [Name] requesting expedited review for Keytruda authorization. The patient has progressive [cancer type] and delaying treatment poses significant clinical risk. Per California regulations, I'm requesting 72-hour turnaround for this urgent oncology case."

Costs and Financial Assistance

Keytruda costs approximately $23,591 per dose (every 6 weeks), making financial assistance crucial for many patients.

Manufacturer Support

  • Merck Patient Assistance Program: Income-based free drug program
  • KEYTRUDA Co-pay Program: May reduce out-of-pocket costs to $25/month for eligible commercial insurance patients
  • Information: Keytruda.com patient resources

California-Specific Resources

  • California Patient Advocate Foundation: Copay relief for specialty drugs
  • Chronic Disease Fund: Assistance for cancer medications
  • CancerCare: Financial assistance and counseling

Insurance Optimization

For specialty tier drugs like Keytruda, consider:

  • Confirming CVS Specialty Pharmacy network requirements
  • Understanding annual out-of-pocket maximums
  • Exploring supplemental coverage options

Frequently Asked Questions

How long does Aetna prior authorization take in California? Standard decisions take 30-45 days, but expedited reviews for urgent cancer cases must be completed within 72 hours per California regulations.

What if Keytruda isn't on my formulary? You can request a formulary exception with clinical justification. If denied, California's IMR process has a 68.6% success rate for overturning oncology specialty drug denials.

Do I need step therapy if I've already failed other treatments? Prior treatment failures should qualify you for step therapy exceptions. Document all previous therapies, doses, and reasons for discontinuation.

Can I get an expedited appeal in California? Yes, for urgent medical situations where delay could jeopardize health. California requires expedited appeals to be decided within 72 hours for commercial plans.

What happens if Aetna upholds the denial after peer-to-peer review? Move to formal internal appeal, then California IMR. The state's independent medical review is binding on the insurer and free for patients.

Does California have special protections for cancer patients? Yes, California has strong patient protection laws, including mandatory coverage of clinical trials, timely access requirements, and robust external review rights through DMHC.

About Counterforce Health: Counterforce Health helps patients, clinicians, and specialty pharmacies turn insurance denials into successful appeals. Our platform analyzes denial letters, identifies specific policy requirements, and generates evidence-backed appeals that speak directly to each payer's criteria. For complex cases like Keytruda denials, we help ensure your appeal includes the right biomarker documentation, clinical evidence, and procedural requirements that California regulators and independent reviewers expect to see.

When to Escalate to State Regulators

If your health plan isn't following California appeal timelines or procedures, contact:

  • DMHC Help Center: 1-888-466-2219 for HMO/managed care plans
  • California Department of Insurance: 1-800-927-4357 for PPO/indemnity plans

Sources & Further Reading

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 determinations. California regulations and insurance policies may change; verify current requirements with official sources.

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