CMS allows Medicare Advantage plans to use step therapy for Part B drugs under federal rules and safeguards. In plain language, a plan may require a new-start patient to try a preferred therapy before covering another option, when the plan’s program and the applicable rules allow it.

This is one reason a medicine guide cannot simply say “Medicare covers it” and stop there. Original Medicare and Medicare Advantage can create very different operational paths.

Questions to answer before the next call or submission
  • Is this Original Medicare or Medicare Advantage?
  • Is the patient a new start for the affected Part B drug?
  • What exact step-therapy policy applies?
  • What preferred drug is required first?
  • What exception criteria are available?
  • What is the expedited path if delay creates medical urgency?

Step therapy is not the same as a universal Medicare rule

The requirement comes from the specific Medicare Advantage plan, not from a blanket rule that every Medicare patient must try the same product. Check the plan’s Evidence of Coverage, utilization-management criteria and current Part B drug policy.

CMS built protections around Part B step therapy

CMS policy states that Part B step therapy may apply to new starts and includes exception/appeal protections. Current therapy history can therefore matter when determining whether a plan can treat the request as a new start.

If the plan says another drug must be tried first, ask for the exact step-therapy criteria and the process for requesting an exception when the prescriber believes the required step is not appropriate.

Biosimilar preference and step therapy can overlap

A Medicare Advantage plan may use biosimilars or other preferred products within an allowed step-therapy program. That is a coverage rule, not a clinical instruction from MedicineCostHelp. The prescriber and patient should decide treatment; the coverage team should determine how to document an exception when needed.

Use the source that actually controls your case

MedicineCostHelp can organize the problem, but the member-specific plan, Medicare program, provider billing record or assistance program makes the actual decision. Save written determinations and reference numbers so the next person does not have to reconstruct the case from scratch.

Official sources

CMS — Medicare Advantage prior authorization and step therapy for Part B drugs →CMS — Medicare Advantage and Part D drug pricing final rule →