CMS Pub. 100-18, ch. 6, § 30.2.1

Part D formularies must include drug categories and classes that cover disease states, consistent

with Part D program requirements. CMS will evaluate the sufficiency of a Part D sponsor’s

formulary categories and classes in conjunction with the formulary drug list to ensure that the

formulary provides access to an acceptable range of Part D drug choices.

Part D sponsors may use existing classification systems, such as those from U.S. Pharmacopeia

(USP) and American Hospital Formulary Service (AHFS), or create their own. CMS will

automatically approve formulary classification systems that are consistent with the USP

classification system, available at www.usp.org. For sponsors that choose to adopt an alternative

classification structure, CMS will check the sponsor’s proposed classification system to

determine if it is similar to USP or other commonly used classification systems, such as the

AHFS Pharmacologic-Therapeutic Classification (information available at

http://www.ahfsdruginformation.com/pt-classification-system.aspx).

Each category or class must include at least two drugs (unless only one drug is available for a

particular category or class, or only two drugs are available but one drug is clinically superior to

the other for a particular category or class), regardless of the classification system that is utilized.

The two drug minimum requirement must be met through the provision of two chemically

distinct drugs. In other words, Part D sponsors will not meet this requirement by including only

two dosage forms or strengths of the same drug, or a brand name drug and its generic equivalent.

Aside from the inclusion of two drugs in each category or class, multiple strengths and dosage

forms should also be available for each covered drug. This should encompass dosage forms used

commonly in long term care (LTC) facilities and home infusion.

CMS may require more than two drugs for particular categories or classes if additional drugs

present unique and important therapeutic advantages in terms of safety and efficacy, and their

absence from the sponsor’s formulary would substantially discourage enrollment by beneficiaries

with certain disease states.