Get Ready: Medicare Model Guidelines Version 9 Are Coming

Medicare Part D coverage for prescription drugs is a federal program that is administered via private entities.  Each approved Medicare Part D plan must offer at least a standard level of coverage.  The list of covered drugs, or formulary, must include at least 2 drugs in the most commonly prescribed categories and classes.  United States Pharmacopeia (USP) works in concert with the Centers for Medicare and Medicaid Services (CMS) to provide and regularly update the specific set of drug categories and classes, known as the Medicare Model Guidelines (MMG).  This provides Medicare Part D plans one option to follow to determine the required covered classes to offer to Medicare beneficiaries.  Medicare Part D plan sponsors also have the option to create their own drug classification listing that must be approved by CMS prior to implementing.

The previous version of the drug categories and classes, called the Medicare Model Guidelines version 8 (MMG v8.0), was published in 2020.  USP released a draft of the updated version 9 document in June 2023.  The draft Medicare Model Guidelines version 9 (MMG v9.0) are intended for use September 15, 2023. The new version includes additions, changes, and removals that have been made to the guidelines.

Class Additions:

Version 9 saw several class additions, with one new class being “Calcitonin Gene-Related Peptide (CGRP) Receptor Antagonists,” which is under the “Antimigraine Agents” category. Under the category “Cardiovascular Agents,” USP added the classes “Mineralocorticoid Receptor Antagonist” and “Sodium-Glucose Co-Transporter 2 Inhibitors (SGLT2i).”  Assuming no changes when the final version is revealed, plans will be required to cover two drugs from each of these classes moving forward.

Along with the changes mentioned above, many new drugs have been FDA approved since the release of MMG v8.0. Twenty new FDA approved drugs were added into the class “Molecular Target Inhibitors.” This number of additions to an already highly populated class is unique, but due to the use in oncology, plans will likely not limit coverage for most of these drugs. Two of the new classes added in this version, “Mineralocorticoid Receptor Antagonist” and “Sodium-Glucose Co-Transporter 2 Inhibitors (SGLT2i)” only contain 3-4 example drugs.  Plans could seize this new opportunity to limit coverage to two drugs in each of the classes, generating competition for formulary position.

Some newly approved drugs have been placed into more general classes that are described as “Other.”  There is the possibility of USP adding additional classes to offer more specificity for these new drugs in the final guidelines.  If additional classes are added, certain drugs may benefit by being the only product or a pair of products in the class.  In this potential scenario, these drugs would likely gain broad coverage from Medicare Part D plans without offering the level of rebates found in highly competitive classes. In contrast, if these drugs remain in the general “Other” class, they may not gain coverage as broadly among Medicare Part D plans.

Class Changes:

The class known in version 8 as “Gamma-aminobutyric Acid (GABA) Augmenting Agents” had a verbiage change to “Gamma-aminobutyric Acid (GABA) Modulating Agents” for version 9. Changing these terms depicts the agents as having a controlling influence on GABA, which more closely fits the actions of the example drugs.

In draft version 9, two previous categories, “Hormonal Agents, Suppressant (Adrenal)” and “Hormonal Agents, Suppressant (Pituitary),” were combined by USP into one category named “Hormonal Agents, Suppressant (Adrenal or Pituitary).” This change would combine more drugs into a single category, allowing plans more discretion to make formulary coverage decisions.

Drug Recategorization:

Along with updating drug categories and classes, USP also adjusted the placement of certain drugs within the existing structure and are shared in the following table.

Medicare Model Guidelines Chart

Watch for the official final release of the Medicare Model Guidelines version 9 in September 2023.  These changes impact manufacturers and Medicare Part D plans regarding formulary coverage and competition.


Posted August 30, 2023

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