By Counterforce Health Team in Onpattro (patisiran) — 10 Nov 2025

How to Get Onpattro (Patisiran) Covered by UnitedHealthcare in California: Complete Coding, Appeals, and IMR Guide

Answer Box: Getting Onpattro (Patisiran) Covered by UnitedHealthcare in California

Onpattro (patisiran) requires prior authorization from UnitedHealthcare OptumRx for hereditary transthyretin amyloidosis polyneuropathy (hATTR-PN). Key requirements: genetic confirmation of pathogenic TTR mutation, neurologist evaluation, and proper ICD-10 coding (E85.1). If denied, file internal appeal within 60 days, then escalate to California's Independent Medical Review (IMR) for binding external review. Success rates are high with proper documentation—appeals overturn ~75% of denials, rising to 82% with peer-to-peer review.

First step today: Contact your neurologist to gather genetic testing results, clinical staging documentation, and request prior authorization through UnitedHealthcare's provider portal.

Medical vs. Pharmacy Benefit Pathway
ICD-10 Coding Requirements
Product Coding: HCPCS, NDC, and Units
Clean Prior Authorization Request
Common Billing Pitfalls
Appeals Process in California
Quick Audit Checklist
FAQ

Medical vs. Pharmacy Benefit Pathway

Onpattro is exclusively billed under the medical benefit because it requires intravenous infusion in a clinical setting every three weeks. This is not a pharmacy benefit drug—you cannot get it through retail, mail-order, or specialty pharmacy.

Key billing pathway:

Site of care: Hospital outpatient or infusion center only
Administration: Healthcare professional required (80-minute IV infusion)
Coverage route: Medical benefit with prior authorization through OptumRx
Billing method: HCPCS J-code on medical claims, not pharmacy claims

Note: Unlike oral medications that go through pharmacy benefits, Onpattro's complex administration requirements place it firmly in the medical benefit category across all UnitedHealthcare plan types.

ICD-10 Coding Requirements

Proper diagnosis coding is critical for UnitedHealthcare approval. The primary code is E85.1 (Neuropathic heredofamilial amyloidosis) for hATTR polyneuropathy cases.

Required Documentation for E85.1

Clinical evidence must include:

Progressive sensorimotor polyneuropathy symptoms
Autonomic neuropathy signs (bowel dysfunction, orthostatic hypotension)
Walking instability and sensory loss
Genetic testing confirming pathogenic TTR variant (essential)
Tissue biopsy showing amyloid deposits with Congo red staining
Exclusion of other causes (diabetic neuropathy, AL amyloidosis)

Disease staging documentation:

Stage 1: Unassisted walking (FAP staging)
Stage 2: Walking assistance required
Stage 3: Wheelchair-bound or bedridden

Tip: Document functional status using standardized scales like mNIS+7 (modified Neuropathy Impairment Score) or 6-minute walk test results—UnitedHealthcare often requires these for initial approval and renewals.

Alternative code E85.2 (Heredofamilial amyloidosis, unspecified) may be used if neuropathic involvement isn't clearly specified, but E85.1 is preferred for Onpattro coverage.

Product Coding: HCPCS, NDC, and Units

Essential Codes

HCPCS J-code: J0222 (injection, patisiran, 0.1 mg per unit)
NDC: 71336-1000-01 (10 mg/5 mL single-dose vial)
Infusion CPT: 96365 (IV infusion, first hour) + 96366 (additional hours)

Dosing and Units Calculation

Weight-based dosing:

Patients <100 kg: 0.3 mg/kg every 3 weeks
Patients ≥100 kg: Fixed 30 mg every 3 weeks

Units conversion example:

75 kg patient = 22.5 mg dose
J0222 billing: 225 units (22.5 mg × 10 units per mg)
Vials needed: 3 vials (22.5 mg ÷ 10 mg per vial, rounded up)

Critical: Bill actual milligrams administered, not number of vials used. Each 0.1 mg = 1 billing unit for J0222.

Clean Prior Authorization Request

A successful PA request to UnitedHealthcare OptumRx must address every criterion in their RNA-Targeted Therapies policy.

UnitedHealthcare's Specific Requirements

Clinical criteria checklist:

✓ Diagnosis of hATTR amyloidosis with polyneuropathy
✓ Pathogenic TTR mutation documentation
✓ Disease severity: PND score ≤ IIIb OR FAP Stage 1-2 OR NIS 5-130 OR KPS ≥60%
✓ No prior liver transplant
✓ No concurrent RNA interference agents or TTR stabilizers
✓ Prescribed by or with neurologist consultation
✓ FDA-compliant dosing

Required attachments:

Genetic test results showing TTR variant
Neurologist consultation notes with staging
Baseline functional assessments (mNIS+7, 6MWT)
Treatment history and rationale

Submission Process

Submit through UnitedHealthcare provider portal or OptumRx's PreCheck Prior Authorization system for faster processing. Standard review takes up to 15 business days; expedited review (72 hours) available if delay poses health risk.

Common Billing Pitfalls

Error Type	Common Mistake	Correction
Units calculation	Billing per vial instead of per mg	Bill actual mg dose × 10 for J0222
Wrong benefit	Submitting to pharmacy benefit	Always bill under medical benefit
Incorrect NDC	Using outdated or wrong NDC	Verify 71336-1000-01 on actual vials
Missing PA	Filing claim without authorization	Obtain PA approval before infusion
Diagnosis mismatch	Using E85.2 or wrong amyloidosis code	Use E85.1 for polyneuropathy cases

Verification Steps

Before submitting claims:

Cross-check patient weight with calculated dose and billed units
Verify NDC matches product packaging
Confirm PA approval is active and covers service dates
Review diagnosis coding aligns with clinical documentation
Validate site of care is appropriate for IV infusion

Appeals Process in California

If UnitedHealthcare denies your Onpattro request, California provides robust appeal rights through a two-tier system.

Internal Appeals Timeline

Appeal Type	Deadline to File	Decision Timeline	Success Rate
Standard internal	60 days from denial	30 calendar days	~75%
Expedited internal	60 days from denial	72 hours	Higher if urgent
Peer-to-peer review	Request within appeal	5-7 days to schedule	82% approval rate

How to file: Submit through UnitedHealthcare provider portal with supporting clinical documentation. Always request peer-to-peer review—this increases overturn rates significantly.

California Independent Medical Review (IMR)

After internal appeals are exhausted, California residents can request binding external review through the Department of Managed Health Care (DMHC).

IMR process:

Eligibility: Complete internal appeals or 30-day response failure
Cost: Free to patients
Timeline: 30 days standard, 7 days expedited
Decision: Binding on UnitedHealthcare
Success rate: High for well-documented rare disease cases

To file IMR: Call DMHC Help Center at 888-466-2219 or submit online at healthhelp.ca.gov.

From our advocates: "We've seen multiple Onpattro denials overturned at IMR when genetic testing, neurologist staging, and functional decline were clearly documented. The key is presenting a complete clinical picture that shows medical necessity according to FDA labeling and clinical guidelines."

Quick Audit Checklist

Before submitting PA requests or claims:

Clinical documentation:

Genetic test confirming pathogenic TTR mutation
Neurologist evaluation with disease staging
Baseline functional assessments (mNIS+7, 6MWT)
ICD-10 E85.1 supported by clinical notes

Coding accuracy:

HCPCS J0222 with correct unit calculation
NDC 71336-1000-01 matches vial packaging
Weight-based dosing documented and calculated correctly
Medical benefit pathway (not pharmacy)

Administrative requirements:

Prior authorization approval obtained
Infusion site appropriate (hospital/infusion center)
All required attachments included
Submission within required timeframes

FAQ

Q: How long does UnitedHealthcare prior authorization take for Onpattro in California? A: Standard PA review takes up to 15 business days. Expedited review (72 hours) is available if delay poses health risk. Using OptumRx's automated PreCheck system can reduce approval time significantly.

Q: What if Onpattro is non-formulary on my UnitedHealthcare plan? A: Request a formulary exception with medical necessity documentation. Non-formulary status doesn't prevent coverage if clinical criteria are met and alternatives are inappropriate.

Q: Can I request expedited appeal if my condition is worsening? A: Yes. California allows expedited appeals (72-hour decision) if delay could seriously jeopardize health. Document clinical urgency in your appeal request.

Q: Does step therapy apply to Onpattro with UnitedHealthcare? A: UnitedHealthcare doesn't require failing other hATTR treatments first, but prohibits concurrent use of other RNA interference agents or TTR stabilizers.

Q: What happens if I miss appeal deadlines? A: Missing the 60-day internal appeal deadline may forfeit your right to challenge the denial. However, California's IMR process may still be available in certain circumstances—contact DMHC for guidance.

Q: How much does Onpattro cost without insurance coverage? A: List price is approximately $450,000-$500,000 annually. Alnylam Assist offers patient support programs including copay assistance and free drug programs for eligible patients.

Counterforce Health helps patients and providers navigate complex prior authorization requirements for specialty medications like Onpattro. Our platform analyzes denial letters, identifies specific coverage criteria, and generates evidence-backed appeals tailored to each payer's requirements. By combining clinical documentation with payer-specific workflows, we help turn insurance denials into approvals, reducing the administrative burden on healthcare teams while improving patient access to life-changing therapies.

For additional support with UnitedHealthcare appeals or other coverage challenges, visit www.counterforcehealth.org.

Sources & Further Reading

This guide is for informational purposes only and does not constitute medical or legal advice. Coverage decisions depend on individual plan terms and clinical circumstances. For specific guidance about your situation, consult your healthcare provider and insurance plan directly. California residents can contact the DMHC Help Center at 888-466-2219 for assistance with insurance issues.

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