In today’s complex healthcare environment, accurate drug information is essential.  Product grouping fields, such as Medi-Span’s Generic Product Identifier (GPI), First Databank’s Generic Code Number (GCN) and GCN Sequence Number (GSN), Multum’s Main Multum Drug Code (MMDC), and Elsevier Gold Standard’s Specific Product ID (SPID), play an important role in how products are displayed for prescribing, dispensing, and claims adjudication. These groupings are generally assigned based on a product’s mechanism of action, chemical structure, or indication.  Fields like these can support a multitude of business functions, from clinical decision making to formulary management.

Drug data, such as these product grouping fields, is initially published when a new product launches, but sometimes post-launch changes are needed. For some compendia, changes can occur as soon as the need for them is identified. For example, if an existing drug product has a new indication approved that necessitates changing its drug grouping, some compendia can simply make the switch to a given data field without impacting other downstream functions.

However, due to the structure of the GPI, more planning and advance notice is needed before a change can be made. These “Planned GPI Changes” typically occur twice a year in the spring and the fall. Instead of making changes throughout the year, Medi-Span gathers and reviews any products with necessary changes and release them all at once, so users know the change is coming. Medi-Span releases advanced information about products that will be impacted by planned changes to their generic product identifiers (GPIs). These updates are usually driven by refinements in drug classification, including adjustments to dosage forms, strengths, or therapeutic classification. GPIs may change at any of the hierarchy levels. This process ensures that the GPI remains an accurate reference for anyone using it.

What is a GPI

The GPI is a unique 14-character hierarchal classification drug identification system. The 14-character code consists of 7 subsets, each providing increasingly more specific information about a given drug product. The subsets are as follows:

• Drug Group
  • Drug Class
    • Drug Subclass
      • Drug Base Name
        • Drug Name and Drug Name Extension
          • Drug Name and Dosage Form
            • Full GPI with Drug Strength and Strength UOM

The GPI groups together pharmaceutically equivalent products and may be a starting point for selecting generic equivalents.

The structure of Medi-Span’s GPI differs when compared to First Databank’s GSN. The GSN numeric value does not correspond to a therapeutic class hierarchy, so changing the value of a given data field, such as the Enhanced Therapeutic Classification (ETC), does not necessitate a change to the GSN. In contrast, the GPI has several built-in features, which may require a higher level of maintenance.  Although they have their differences, there is no right or wrong answer on which identifier to use.

Why Product Grouping Fields are Important

The product grouping fields described here aren’t just a backend code; they play a crucial role across many healthcare settings:

Hospitals integrate these fields into electronic medical records (EMRs) to power clinical screening, which allows systems to detect things like drug interactions, dosing, and other alerts. This reduces the risk of medication errors and improves patient safety.

Retail pharmacies use product grouping fields to help drive product selection and substitution.  For example, a pharmacist can identify all brand and generic products for a specific medication that are the same in terms of their active ingredient(s), strength or concentration, route of administration, and dosage form. They combine this with other data, such as the drug’s Orange Book Code, to determine substitution options.

Pharmaceutical manufacturers use product grouping data to track real-world performance of a drug class, analyze prescribing behavior, and evaluate population outcomes, which allows for quick decision making.

Analytics firms and consultants use the product grouping fields to recognize patterns and trends based on medication therapies; for example, identifying patients taking a specific drug plus at least one other prescription drug.

PBMs and payers leverage product grouping fields in formulary management.  They may exclude drugs based on therapeutic class or active ingredient or can use these groupings to set utilization management edits or coverage rules.

PHSL has extensive experience with drug compendia. Contact us with your questions about product grouping fields and planned GPI changes today!

 

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