CurrentCentenePolicy MCPB.ST.00

Medicare Part B Step Therapy (PDF)

Defines drugs subject to Medicare Part B step therapy requirements (preferred prior agents or prior lines of therapy) and indication-specific step conditions; may require prior authorization. Applies to new starts (no receipt of the drug in prior 365 days).

Policy Summary

PayerCentene

PolicyMedicare Part B Step Therapy (PDF)

Policy CodePolicy MCPB.ST.00

Change TypeNo material change

Effective DateJan 1, 2021

Next Review Date

Key ActionObtain prior authorization when applicable and document prior trials of preferred agents or prior lines of therapy as specified.

SourceLink

POLICY UPDATE CHANGES

No material clinical/coverage changes.

~120Drugs listed with step requirements (approx.)

365New start lookback period (days)

MultipleIndication-specific exceptions/biomarker rules

Coverage Summary

Scope: Defines Medicare Part B drugs subject to step therapy (requiring trial of preferred prior agents or specified prior lines of therapy) for specific indications; applies to new starts (member has not received the drug in the prior 365 days), and may require prior authorization.

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Provider Actions & Operational Requirements

Prior Authorization

Prior authorization may be required

Many listed Part B agents 'may require prior authorization' per drug and indication; provider must obtain PA when applicable and document prior trial(s) of preferred agents or prior lines of therapy as specified.

Documentation Required

Document prior therapies and timing

Providers must document previous therapies (agent names, dates, responses), eligibility for exceptions (e.g., ineligibility for chemo, transplant eligibility, PD-L1/biomarker results), and reason for exception if requesting bypass of step.

Denial Risk

Initial dose-only coverage risk for certain cell therapies

For some CAR-T and cell therapies (e.g., Brexucabtagene, Idecabtagene, Tisagenlecleucel, Ciltacabtagene, Obecabtagene), only the initial treatment dose is covered; subsequent doses will not be covered.

Billing Rule

Follow biosimilar/formulary substitutions

For many agents, coverage requires using specified biosimilars or preferred brand alternatives first (lists provided per agent); providers should bill the covered product per the step hierarchy (e.g., step to Zarxio for filgrastim, Udenyca/Fulphila for pegfilgrastim, Retacrit for epoetin/darbepoetin, specified trastuzumab biosimilars before Herceptin).

Background

Background: Step therapy requires trial of a preferred therapeutic alternative prior to coverage of a non-preferred Part B drug for a specific indication. The policy provides drug-by-drug step hierarchies that list required prior agents or prior lines of therapy and any biosimilar/preferred product substitutions. It may require prior authorization and specifies documentation expectations for prior therapies and exception justifications.

Scope/context note: This policy applies to Medicare Part B drug coverage decisions for new starts and outlines indication-specific step requirements, but explicitly does not replace existing Medicare rules and regulations governing the applicable agents.

Definitions & Thresholds

Policy thresholds and special definitions

New start definitionMember has not received the drug for the past 365 days

PD-L1 high expression (atezolizumab)PD-L1 ≥50% (TC ≥50%) or IC ≥10%

PD-L1 CPS threshold (pembrolizumab)CPS ≥1 (or CPS ≥10 where specified)

NSCLC stage IB-IIIA PD-L1TPS ≥1%

Very high fracture risk (romosozumab exception)Recent osteoporotic fracture within 12 months OR BMD T-score ≤ -3.0 OR BMD T-score ≤ -2.5 plus major osteoporotic fracture