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  4. Drug Development Tool (DDT) Qualification Programs
  5. DDT Glossary
  1. Drug Development Tool (DDT) Qualification Programs

DDT Glossary

Animal Models: For DDT considerations, an animal model is one in which a disease process/pathological condition can be investigated, and in which the disease/condition in multiple important aspects corresponds to the human disease/condition of interest.  The animal model(s) should meet the four criteria outlined in the Animal Rule such that the effectiveness of the product in animals can be a reliable indicator of its effectiveness in humans.

Biomarkers: A defined characteristic that is measured as an indicator of normal biological processes, pathogenic processes, or responses to an exposure or intervention, including therapeutic interventions. Molecular, histologic, radiographic, or physiologic characteristics are types of biomarkers. A biomarker is not an assessment of how an individual feels, functions, or survives.  

Clinical outcome assessments (COA) : Assessment of a clinical outcome can be made through report by a clinician, a patient, a non-clinician observer or through a performance-based assessment. There are four types of COAs.

  • Patient-reported outcome (PRO) measures: A measurement based on a report that comes directly from the patient (i.e., study subject) about the status of a patient’s health condition without amendment or interpretation of the patient’s response by a clinician or anyone else. A PRO can be measured by self-report or by interview provided that the interviewer records only the patient’s response. Symptoms or other unobservable concepts known only to the patient can only be measured by PRO measures. PROs can also assess the patient perspective on functioning or activities that may also be observable by others. PRO measures include:  
    • Rating scales (e.g., numeric rating scale of pain intensity or Minnesota Living with Heart Failure Questionnaire for assessing heart failure)
    • Counts of events (e.g., patient-completed log of emesis episodes or micturition episodes)
  • Observer reported outcome (ObsRO) measures: A measurement based on a report of observable signs, events or behaviors related to a patient’s health condition by someone other than the patient or a health professional. Generally, ObsROs are reported by a parent, caregiver, or someone who observes the patient in daily life and are particularly useful for patients who cannot report for themselves (e.g., infants or individuals who are cognitively impaired). An ObsRO measure does not include medical judgment or interpretation. ObsRO measures include:
    • Rating scales, such as:
      •  Acute Otitis Media Severity of Symptoms scale (AOM-SOS), a measure used to assess signs and behaviors related to acute otitis media in infants
      •  Face, Legs, Activity, Cry, Consolability scale (FLACC), a measure used to assess signs and behaviors related to pain
    • Counts of events (e.g., observer-completed log of seizure episodes)
  • Clinician-reported outcome (ClinRO) measures: A measurement based on a report that comes from a trained health-care professional after observation of a patient’s health condition. Most ClinRO measures involve a clinical judgment or interpretation of the observable signs, behaviors, or other manifestations related to a disease or condition. ClinRO measures cannot directly assess symptoms that are known only to the patient. ClinRO measures include:
    • Reports of particular clinical findings (e.g., presence of a skin lesion or swollen lymph nodes) or clinical events (stroke, heart attack, death, hospitalization for a particular cause), which can be based on clinical observations together with biomarker data, such as electrocardiogram (ECG) and creatine phosphokinase (CPK) results supporting a myocardial infarction
    • Rating scales, such as:
      • Psoriasis Area and Severity Index (PASI) for measurement of severity and extent of a patient’s psoriasis
      • Hamilton Depression Rating Scale (HAM-D) for assessment of depression
  • Performance outcome (PerfO) measures: A measurement based on a task(s) performed by a patient according to instructions that is administered by a health care professional. PerfOs require patient cooperation and motivation. PerfO measures include:
    • Measures of gait speed (e.g., timed 25 foot walk test)
    • Measures of memory (e.g., word recall test)

Context of use: A statement that fully and clearly describes the way the medical product development tool is to be used and the medical product development-related purpose of the use.

DDT-specific guidance: Document signed by the CDER Director at the conclusion of the qualification process indicating that a DDT is qualified for a specific context of use.  This document includes information relevant for use of the qualified DDT in its specific context of use, along with its assessment and conclusion of the supporting data for qualification.  This document is posted on the DDT Qualification Web Site to ensure public availability of the DDT and the corresponding notice will be posted in the Federal Register.  In accord with Good Guidance Practices, the initial posting of the qualification will be as a draft appendix to the DDT qualification process guidance, with an identified period for public comment.   Subsequent to that, the comments will be considered and the appendix reposted as a final guidance appendix with any revisions that are appropriate. Once qualified, DDTs will be publicly available for use in any drug development program for the qualified context of use. 

Drug Development Tool (DDT): A measurement or method (and associated materials) that aids drug development.  DDTs include, but are not limited to, biomarkers, clinical outcome assessments, and animal models.  DDTs suitable for the CDER DDT Qualification process are a subset of all types of DDTs, and should be intended for potential use, over time, in multiple drug development programs. DDTs used as clinical outcome assessments may sometimes be called an instrument.  The term “instrument,” or “tool,” refers to the means to capture data plus all the information and documentation that support its use within the intended context of use.

Publicly Available: The DDT is available to any user for inclusion in any drug development program in its qualified form and context of use at the time of its qualification.  FDA will promote public knowledge of the qualified DDTs by listing them on the FDA web site.  Qualification does not waive ownership rights/intellectual property rights.

When requestors enter the qualification process, they agree that the qualified DDT will be made publicly available for use in drug development programs in the specified context of use.  To this effect, the notice of the DDT-specific guidance will be published in the Federal Register and the DDT guidance along with summary reviews of the information submitted to support the qualification decision will be posted on this website.  When a DDT is a proprietary instrument available for use only with the agreement of the owner of the DDT instrument (e.g., specific questionnaires), CDER will direct the public on how to obtain the qualified DDT from the DDT requestor. 

Qualification: A conclusion, based on a formal regulatory process, that within the stated context of use, a medical product development tool can be relied upon to have a specific interpretation and application in medical product development and regulatory review.

Qualification Programs: CDER programs developed to include the DDT Qualification Process and the regulatory infrastructure and documentation needed to support this Process.

Qualification Process: Process for consultation and advice and review of potential DDTs as outlined in the guidance.

Qualification Review Team (QRT): The QRT is comprised of a multidisciplinary group of FDA staff.  Each team is recruited based upon the specific DDT and the context of use proposed by the requestor.
 

Sponsor: A person or entity that submits an application for an IND to conduct clinical trials of an investigational product.

Requestor: Requestor is a person, group, organization or consortium that takes responsibility for and initiates a DDT qualification proposal.

Submission for DDT qualification: Any correspondence and documents provided to CDER as part of the qualification process.  Submissions are classified under the following categories:

  • Pre-submission request
  • Letter of Intent
  • Briefing Package
  • Supporting Document(s) for Consultation and Advice Stage
  • Qualification Package

Within these categories, requestors should provide any documents relevant to DDT development and qualification appropriate for the purpose of the submission in that stage of the DDT Qualification process.  Requestors are strongly encouraged to consider the use of relevant data standards (e.g., CDISC) in data submission.

Clinical benefit: The effect of treatment on how a patient survives, feels, or functions. Clinical benefit can be demonstrated by either an effectiveness or safety advantage. For example, the treatment effect may be measured as an improvement or delay in the development of symptoms or as a reduction or delay in treatment-related toxicity.

21 CFR 314.126.

21 CFR 314.126.

Additional terminology is available at the BEST (Biomarkers, EndpointS, and other Tools) Resource

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