VA Drug Terminology Projects Update:VA Drug Terminology Projects Update: NDF-RT, the New Drug NDF-RT, the New Drug

Transaction, And BeyondTransaction, And Beyond

VA: Steve Brown, Mike Lincoln

Apelon: Mark Tuttle, John Carter, Mark Erlbaum

October 3, 2002

Presented to HL7 Vocabulary TC Meeting

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OverviewOverview

• NDF-RT: Current state and plans• New Drug Transaction: Introduction• Interagency cooperation update

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Background:Background:VA National Drug File (NDF)VA National Drug File (NDF)

• Centrally maintained and distributed, locally modified and deployed. Uses include:• VistA POE Decision Support• Mail out pharmacy (57 million in 2001)

• Single-inheritance hierarchy including • VA Drug Classes (anti-hypertensives, beta-blockers)• Products (Ampicillin 250 mg tab)• Ingredients (carbidopa, codeine phosphate)• NDCs (acetaminophen 325 mg tab, bottle of 100)

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NDF Reference Terminology NDF Reference Terminology (NDF-RT)(NDF-RT)

• Explicit, multi-hierarchical model• Centered on drug ingredients for function,

maintenance and economies of scale• Semi-algorithmic initialization followed by human

review• Authoritative, collaborative content (FDA, NLM,

HL7, others)• VA’s ERT strategy

• Subject Matter Experts use COTS tools to develop, modify, & maintain enterprise standards

• Abstracted terminology services

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Simplified NDF-RT ModelSimplified NDF-RT Model

Chemical Structure

StrengthDose Form

Route of Adm.(HL-7)

National DrugCodes (NDCs)

Structural ID

Pharmacokinetics

Physiologic Effect

Mechanism of Action

Database Links MeSH, CUIs, …

Therapeutic Intent

Active Ingredients

Clinical Drugs

Packaged Drugs

VA Drug Classes

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NDF-RT ContentNDF-RT Content

• Drug Hierarchy• 3,977 Active Ingredients (incl. salts & esters)• 11,345 Orderable Drugs (= VA Products)• 87,210 Packaged Drugs (NDCs)

• Initialized from …• VA National Drug File (Sept 2001)

• NLM RxNorm Drug Names (Dec 2001)

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NDF-RT ContentNDF-RT Content

• Reference Hierarchies• 3,994 Diseases & Manifestations (“Intended

Therapeutic Use” hierarchy)• 489 Chemical Structure categories• 402 Mechanism of Action & Physiologic Effect

categories• 154 HL7 Dose forms• 58 Clinical Kinetics categories

• Initialized from MeSH & HL7

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Modeling Active IngredientsModeling Active Ingredients

• 4000 active ingredients & 87,000 NDC level products

• Descriptive aspects inherited down the hierarchy to orderable drugs & packaged NDC drug products which contain the active ingredients modeled

• Increases modeling efficiency & productivity via “inheritance”

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Covering Drugs Ordered in Covering Drugs Ordered in One VAMC (June 2000)One VAMC (June 2000)

• Extracted 488 active NDF-RT ingredient names from sample of ordered drugs

• Modeling 488 (12.3%) of all 3977 active ingredients in NDF-RT would cover at least one ingredient in:• 63.7% (7228/11345) of all NDF-RT

orderable drugs• 78.2% (68194/87210) of all NDF-RT

packaged drugs (NDCs)

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Est. Time to Review NDF-RTEst. Time to Review NDF-RT

• Time & motion study• Averaged 12-13 minutes per concept,

range 5-30 minutes• Est. throughput = 4 concepts per hour

• Approx. 1000 person hours for ~4000 active ingredient concepts in NDF-RT

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Upcoming WorkUpcoming Work

• VA Contract awarded 09/2002, to be completed Spring 2003

• NIGMS• Includes support for reference hierarchy

development and some human review• Focuses on meeting needs of

pharmacogenomic research network

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Background: VABackground: VANew Drug TransactionNew Drug Transaction

• Thousands of NDC changes per year• Hundreds of clinical drug changes per

year• Tens of New Molecular Entities per year

• How to maintain?

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VA Formulary Updates: VA Formulary Updates: Current SituationCurrent Situation

• Manual system for review and entry into national formulary• Daily entry, quarterly publication

• Multiple sources of data• Commercial KB’s, FDA, trade pubs, requests from

field• Local hospitals also can add updates, these are

then transmitted monthly to central office for review (workload dependent)

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New Drug Transaction PlanNew Drug Transaction Plan

• Create an XML message based on publicly available data sources to carry drug information

• Develop a semi-automated method and software tool to review and accept new drugs into the formulary

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A Little Plan DetailA Little Plan Detail

• Multiple “levels”: NDC, Clinical drug, NME

• 3 “flavors”: new, change, retire• A single new NDC may cause an

upward chain of updates

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New Dose Form Example: New Dose Form Example: CopaxoneCopaxone

• Generic Name: Glatiramer Acetate• Treats: Multiple Sclerosis• Currently, the only GA packaged drug in

NDF-RT is:• GLATIRAMER ACETATE 20MG/ML SYR [NDC: 66914-1009- 1]

• Injectable solution

• Add:• GLATIRAMER ACETATE 20MG/VIL [NDC: 0480-0126-84]

• Powder, lyophilized for solution

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Necessary Transaction StepsNecessary Transaction Steps

• “Clinical Drug” is the level of the dose form information

• “Dose form” is different (???) because existing NDC is already in solution

• Potential new concepts:• Clinical drug concept (???)• NDC-level concept

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Government Drug Terminology Government Drug Terminology “Partners”“Partners”

NCI FDADrug Company

PTO

VA

DoD CMS

CDC

NLM

DEA

NIGMS

IHS

Drafted

In Place

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FDA LabelingFDA Labeling

• Being created as a Structured Document using HL7 Clinical Document Architecture

• Label Warehouse System prototype in development

• Selected data to be shared with NLM to help populate RxNorm

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NIGMSNIGMS

• Helping develop reference hierarchies, especially pharmacokinetics

• Tied to PharmGKB project at Stanford• Thanks to Chris Chute!

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NCI Experimental AgentsNCI Experimental Agents

• Approximately 300 agents, ranging from the common to the very experimental

• A separate drug class hierarchy, focused on mechanisms of action and specialized anti-neoplastic categories

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Vision:Vision:Interagency Information Flow for the Interagency Information Flow for the

New Drug TransactionNew Drug Transaction

FDA NLM

HealthePeople& Other Federal

Systems

VA

(Approved Drug

Information)

NDTElectronic Label

(FDA+NLM Information)

(Off-Label Indications, VA MoA, other VA DSS aggregations, and other usage information)

(Additional structure information)

These Flows to be HL7 candidate Standards

Non-FederalUsers

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ChallengesChallenges

• Delivering drug definitions and reference hierarchies with “face validity”

• Managing multi-agency, multi-institution collaboration• Varying needs & expectations

• Information model, terminology model, knowledge base interaction

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