CurrentMass General Brigham Health PlanPolicy N/A

Ziihera (zanidatamab-hrii) — Coverage Criteria (Medical Benefit)

Policy governing prior authorization and medical benefit management of Ziihera (zanidatamab-hrii) for adults with previously treated, unresectable or metastatic HER2-positive biliary tract cancer under the Mass General Brigham Health Plan (MassHealth UPPL Plan).

Policy Summary

PayerMass General Brigham Health Plan

PolicyZiihera (zanidatamab-hrii) — Coverage Criteria (Medical Benefit)

Policy CodePolicy N/A

Change TypeNo material change

Effective DateMay 12, 2025

Next Review DateN/A

Key ActionSubmit prior authorization with prescriber attestation of IHC 3+ HER2 BTC, patient age, weight, dosing, and documentation of inadequate response to one gemcitabine-containing regimen.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 monthsinitial approval duration

12 monthsreauthorization duration

IHC 3+HER2 expression required

1 gemcitabine regimenprior therapy required

Coverage Criteria for Ziihera (zanidatamab-hrii)

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Initial Therapy

Authorization may be granted when ALL of the following are met:

Initial coverage criteria: Diagnosis of unresectable or metastatic HER2-positive (IHC 3+) biliary tract cancer (BTC).

Initial coverage criteria: Member is ≥ 18 years of age.

Initial coverage criteria: Prescriber is an oncologist.

Initial coverage criteria: Documentation of current weight and appropriate dosing.

Initial coverage criteria: Inadequate response or adverse reaction to ONE prior gemcitabine-containing regimen for BTC.

Continuation Therapy

Continuation of therapy criteria:

Continuation: Prescriber resubmission that infers a positive clinical response to therapy is required for continuation/reauthorization.

Reauthorizations will be granted for 12 months (see limitations).

Ziihera (zanidatamab-hrii) will be managed through the medical benefit only. All requests for administration should be submitted and authorized under the medical benefit with prior authorization in place; the medication is not covered through the pharmacy benefit for medical administration.

Continuation / Reauthorization

Continuation/Reauthorization

Reauthorization process and duration

Reauthorization duration and requirement: Prescriber must resubmit documentation that infers ongoing clinical benefit; reauthorizations will be granted for 12 months.12 months

Initial approval duration is 6 months; subsequent reauthorizations 12 months.

Provider Actions and Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required; Ziihera (zanidatamab-hrii) will be managed through the medical benefit only with PA.

Medical benefit only
Contact: Phone 877-519-1908; Fax 855-540-3693
Effective date: 2025-05-12

Step Therapy

No step-therapy program specified beyond the prior authorization requirement. Specialty limitations: N/A.

Step therapy: None beyond PA
Specialty limitations: N/A

Documentation Required

Required Documentation

Prescriber must provide documentation to support medical necessity for initiation or continuation of Ziihera, including prescriber attestation of diagnosis (IHC 3+ HER2-positive biliary tract cancer), patient age, current weight and appropriate dosing, and prior treatment history.

Prescriber attestation of unresectable or metastatic HER2-positive (IHC 3+) biliary tract cancer
Patient age (must be ≥18 years)
Current weight and dosing information
Documentation of inadequate response or intolerance to ONE prior gemcitabine-containing regimen for BTC
Prescriber specialty: oncologist

Denial Risk

Triggers for Denial

Authorization will be denied if required clinical criteria or documentation are missing or not met.

No documented diagnosis of unresectable or metastatic HER2-positive (IHC 3+) biliary tract cancer
Member is <18 years of age or age not documented
Missing current weight or dosing information
No documentation of inadequate response or adverse reaction to ONE prior gemcitabine-containing regimen for BTC
Prescriber is not an oncologist or prescriber specialty not provided

Step	Requirement	Notes
1	Prior therapy with a gemcitabine-containing regimen is required before coverage.	Inadequate response or adverse reaction to one prior gemcitabine-containing regimen must be documented for initial authorization.

Definitions

HER2-positive (IHC 3+): definition and requirement for Ziihera

DefinitionTumor expression level defined by immunohistochemistry (IHC) score of 3+

Required for indicationIHC 3+ HER2 status is required for Ziihera use in biliary tract cancer (BTC)

Test typeHER2 status must be detected by an FDA‑approved test

Clinical contextIndication applies to adults with previously treated, unresectable or metastatic BTC

Documentation to supportPrescriber must attest to diagnosis of unresectable or metastatic HER2‑positive (IHC 3+) BTC

Background

Ziihera (zanidatamab-hrii) is indicated for adults with previously treated, unresectable or metastatic HER2-positive (IHC 3+) biliary tract cancer as detected by an FDA‑approved test. Authorization may be reviewed for members who are new to the plan and currently receiving treatment with the medication.

Per plan implementation notes, prior authorization is required and the drug will be administered under the medical benefit only (effective 05/12/2025).