CurrentMass General Brigham Health PlanPolicy N/A

Prior authorization and coverage criteria for Herceptin (trastuzumab) and specified biosimilars

Prior authorization and coverage criteria for Herceptin (trastuzumab) and specified biosimilars for HER2-overexpressing breast cancer, HER2-overexpressing metastatic gastric/GEJ adenocarcinoma, and certain HER2-positive metastatic colorectal cancer; applies to Mass General Brigham Health Plan members. Affects prescribers and pharmacy/medical benefit adjudication.

Policy Summary

PayerMass General Brigham Health Plan

PolicyHerceptin (trastuzumab) and specified biosimilars — prior authorization and coverage criteria

Policy CodePolicy N/A

Change TypeAdded biosimilar (Hercessi)formatting/references updated

Effective DateJul 1, 2025

Next Review DateN/A

Key ActionSubmit prior authorization with documentation of HER2 status, prescriber specialty, appropriate dosing, and required prior regimens or combination therapy where applicable.

SourceLink

POLICY UPDATE CHANGES

Added new biosimilar Hercessi (trastuzumab-strf) to the list of covered agents and to criteria.

Updated formatting and references and added new biosimilar to criteria.

3 indicationsCancer types covered (breast, gastric/GEJ, colorectal)

12 monthsInitial and reauthorization approval duration

MultipleListed trastuzumab biosimilars included

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Coverage Criteria for Trastuzumab Products

Breast Cancer

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

Breast Cancer initial criteria: Diagnosis of HER2-overexpressing breast cancer

Breast Cancer initial criteria: Prescriber is an oncologist

Breast Cancer initial criteria: Appropriate dosing (weight required)

Metastatic Gastric or GEJ Adenocarcinoma

Authorization may be granted when ALL of the following are met for metastatic gastric or GEJ adenocarcinoma:

Gastric/GEJ criteria: Requested agent is one of the listed trastuzumab products (e.g., Herceptin, Hercessi, Herzuma, Kanjinti, Ogivri, Ontruzant, Trazimera)

Gastric/GEJ criteria: Diagnosis of HER2-overexpressing metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma

Gastric/GEJ criteria: Prescriber is an oncologist

Gastric/GEJ criteria: Appropriate dosing (weight required)

Gastric/GEJ criteria: Requested agent will be used in combination with chemotherapy

Unresectable or Metastatic Colorectal Cancer (mCRC)

Authorization may be granted when ALL of the following are met for unresectable or metastatic colorectal cancer:

mCRC criteria: Requested agent is one of the listed trastuzumab products (e.g., Herceptin, Hercessi, Herzuma, Kanjinti, Ogivri, Ontruzant, Trazimera)

mCRC criteria: Diagnosis of RAS wild-type, HER2-positive unresectable or metastatic colorectal cancer

mCRC criteria: Prescriber is an oncologist

mCRC criteria: Appropriate dosing (weight required)

ONE of the following prior regimen requirements:

Continuation of Therapy

Continuation of therapy

Continuation: Resubmission by prescriber will infer a positive response to therapy

Requests for trastuzumab products that were obtained as samples or provided through a manufacturer's patient assistance program are excluded from case‑by‑case authorization review and will not be accepted for coverage consideration under this policy. If a member is currently receiving therapy that was supplied as a sample or via a manufacturer assistance program, that supply does not create an eligibility pathway for continuing coverage through the plan.

When required documentation supporting the criteria is not provided, the request is likely to be denied in accordance with the plan’s authorization policies. Clinically relevant documentation includes verified diagnosis (e.g., HER2‑overexpressing disease or RAS wild‑type, HER2‑positive colorectal cancer where applicable), prescriber specialty (oncologist), and dosing information (including weight where weight‑based dosing is required). Absence of these items typically results in denial unless a case‑by‑case review for members new to the plan determines otherwise.

Provider Actions and Operational Requirements

Prior Authorization

Prior authorization required for Herceptin and biosimilars

Prior authorization is required for Herceptin and the listed trastuzumab biosimilars under the plan; authorizations may be reviewed on a case‑by‑case basis for members who are new to the plan and currently receiving treatment.

Step Therapy

Step therapy: prior regimen required for mCRC

For unresectable or metastatic colorectal cancer, approval requires inadequate response or an adverse reaction to, or contraindication to, ONE of the specified prior regimens (e.g., CAPEOX, FOLFOX, FOLFIRI, FOLFOXIRI, FOLFIRINOX, irinotecan‑based or oxaliplatin‑based therapy) before trastuzumab will be authorized.

Prior regimen options listed: CAPEOX; FOLFOX; FOLFIRI; FOLFOXIRI; FOLFIRINOX; irinotecan‑based therapy; oxaliplatin‑based therapy

Covered Regimens and Prior Regimen Requirements

Prior regimen (mCRC)
CAPEOX
FOLFOX
FOLFIRI
FOLFOXIRI
FOLFIRINOX
Irinotecan-based therapy
Oxaliplatin-based therapy

Covered Trastuzumab Products and Codes

Covered trastuzumab productsmixedCovered

Herceptin	trastuzumab (reference product) listed as covered product
Hercessi	trastuzumab-strf (biosimilar) listed as covered product
Herceptin Hylecta	trastuzumab-hyaluronidase-oysk listed
Herzuma	trastuzumab-pkrb listed
Ogivri	trastuzumab-dkst listed
Kanjinti	trastuzumab-anns listed
Ontruzant	trastuzumab-dttb listed
Trazimera	trastuzumab-qyyp listed

Key Definitions and Biomarker Requirements

HER2-overexpressing / HER2-positive — definition

DefinitionTumors demonstrating HER2 (ERBB2) overexpression or gene amplification as defined by FDA labeling and guideline definitions; for colorectal cancer this policy requires both RAS wild-type status and HER2-positive disease.

FDA contextHerceptin (trastuzumab) and FDA‑approved biosimilars are indicated for HER2‑overexpressing breast cancer and HER2‑overexpressing metastatic gastric/GEJ adenocarcinoma per FDA labeling.

Guideline alignmentNCCN guidelines support use of trastuzumab for HER2‑positive disease per FDA labeling and consider FDA‑approved biosimilars appropriate substitutes.

Colorectal specificFor unresectable or metastatic colorectal cancer, HER2‑positive designation is required in the setting of RAS wild‑type tumors to meet policy criteria.

HER2 (HERZ/neu) — HER2‑overexpressing / HER2‑positive per FDA labeling

Line of Therapy and Salvage Use

Salvage

Salvage-line use: Used for unresectable/metastatic disease after progression following fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy (policy requires prior regimen failure or contraindication to specified regimens)

Background

Trastuzumab is a monoclonal antibody that acts as a HER2 (ERBB2) receptor antagonist. It is FDA‑approved for the treatment of HER2‑overexpressing breast cancer and HER2‑overexpressing metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma. Listed trastuzumab biosimilars share the same FDA‑approved indications and are considered appropriate therapeutic alternatives when used according to the policy and supporting clinical guidance.

Policy Summary

PayerMass General Brigham Health Plan

PolicyHerceptin (trastuzumab) and specified biosimilars — prior authorization and coverage criteria

Policy CodePolicy N/A

Change TypeAdded biosimilar (Hercessi)formatting/references updated

Effective DateJul 1, 2025

Next Review DateN/A

Key ActionSubmit prior authorization with documentation of HER2 status, prescriber specialty, appropriate dosing, and required prior regimens or combination therapy where applicable.

SourceLink

On This Page

Inadequate response or adverse reaction to OR contraindication to ONE of the specified prior regimens (see Appendix): CAPEOX; FOLFOX; FOLFIRI; FOLFOXIRI; FOLFIRINOX; irinotecan-based therapy; oxaliplatin-based therapy

See Appendix for regimen components

mCRC criteria: Requested agent will be used in combination with tucatinib (Tukysa)

Documentation Required

Required documentation (diagnosis, biomarkers, prescriber, dosing, combination/prior regimens)

Provide documentation of the specific diagnosis, relevant biomarker status, prescriber specialty, and dosing/weight; also document combination therapy or prior regimens where required by indication.

Breast cancer: diagnosis of HER2‑overexpressing breast cancer; prescriber is an oncologist; appropriate dosing with weight
Gastric/GEJ: diagnosis of HER2‑overexpressing metastatic gastric/GEJ adenocarcinoma; prescriber is an oncologist; appropriate dosing with weight; documentation that agent will be used in combination with chemotherapy
mCRC: diagnosis of RAS wild‑type, HER2‑positive unresectable or metastatic colorectal cancer; prescriber is an oncologist; appropriate dosing with weight; documentation of inadequate response/adverse reaction or contraindication to required prior regimens and that trastuzumab will be used with tucatinib

Denial Risk

Denial triggers: missing documentation or lack of case‑by‑case review for continuing members

Requests may be denied if the member is not new to the plan without a case‑by‑case review and if required documentation for the coverage criteria is not provided (for example: diagnosis, prescriber specialty, dosing/weight, required combination therapy, or evidence of prior regimens for mCRC).

Lack of required documentation for criteria (diagnosis, prescriber specialty, dosing, combination therapy where required) may trigger denial
Members not new to the plan may be subject to denial absent a case‑by‑case review

HER2 status required

HER2‑overexpressing / HER2‑positive as defined by FDA labeling for trastuzumab indications.

Indications coveredFDA‑approved indications include HER2‑overexpressing breast cancer and HER2‑overexpressing metastatic gastric/GEJ adenocarcinoma; biosimilars share these indications.

Biosimilar equivalenceListed trastuzumab biosimilars have the same exact FDA‑approved indications as the reference product and are considered appropriate substitutes per NCCN guidance.

RAS — RAS wild‑type required for eligibility in mCRC

RAS requirementRAS wild‑type (WT) status is required for eligibility for trastuzumab in unresectable or metastatic colorectal cancer (mCRC).

Combined biomarker requirementPolicy requires both RAS WT and HER2‑positive designation for mCRC coverage criteria.

Documentation noteDiagnosis must specify RAS wild‑type, HER2‑positive unresectable or metastatic colorectal cancer to meet authorization criteria.