A patient registry has been defined as “an organized system that uses observational study methods to collect uniform data (clinical and other) to evaluate specified outcomes for a population defined by a particular disease, condition or exposure, and that serves a predetermined scientific, clinical or policy purpose.”(1) Patient registries provide an infrastructure for the standardized recording of data from routine clinical practice on individual patients classified by a characteristic or an event. These may include the diagnosis of a disease (disease registry), the occurrence of a condition (e.g., pregnancy registry), a birth defect (e.g., birth defect registry), a molecular or genomic or any other patient characteristics, or an encounter with particular healthcare service.(2, 3)

Studies based on registries (registry studies) aim to investigate a research question using the infrastructure of new or existing registries for patient recruitment and data collection. The objectives of these studies may include epidemiological data collection, trend analysis, efficacy, safety, long term and short term outcomes of different treatment options, and patient-reported outcomes such as quality of life and patient satisfaction.(3) A registry study may implement primary data collection and/or secondary use of data collected in a patient registry for a different purpose from the given study. When ‘patient’ and ‘registry’ are used in combination (i.e., patient registry), they highlight the focus of the dataset on health information.(4)More importantly, such registry studies offer different stakeholders in the pharmaceutical industry (including prescribers, healthcare providers, regulators, payers, government, and also the patients) an additional layer of evidence beyond clinical trials, surrounding the efficacy and safety of drugs and medical devices. (1)

Patient registries are particularly useful for generalizing the findings of clinical trials to populations not included in those trials. Additionally, they can also help evaluate the impact of physician decision-making and actions on care delivery. Registries are also increasingly being utilized for observational comparative effectiveness studies as they have proven to be cost-effective while providing useful information in comparison with the alternative methods.(2) Registry data have great potential to enhance the efficiency of clinical trials, making them less expensive, and speeding up the availability of new treatments to patients. Depending on the capabilities and characteristics (e.g., interoperability, connectivity, flexibility, sustainability), a registry can be used either as a) an observational data source for the generation of clinical evidence and hypotheses or b) an important reusable element of the clinical trial infrastructure for prospective randomized studies.(5) Information collected in clinical observational registries, such as demographics, medical history, diagnosis, and outcomes data, often overlap with clinical trial data. Therefore, integration of clinical trials within registries may offer opportunities to 1) Avoid data collection duplicity, 2) More efficient identification and recruitment of patients, 3) Faster database lock, 4) Faster critical decision-making, and 5) Reduction of clinical trial costs.(5)

Considering the extent of impact that registry studies can have on the usage of drugs and medical devices, factors surrounding patient privacy, confidentiality, ethics, and other regulatory issues gain extreme significance. Regulatory oversight is essential to ensure that the outcomes of registry audits are done appropriately, avoiding misguiding claims of efficacy and/ or safety. Thus it becomes crucial for regulators to assess whether the historical evidence generated from registry studies demonstrates the reliability, robustness, and relevance to support regulatory decision-making. Additionally, the assessment of an existing registry can also be done to see if it contains the elements for a randomized clinical trial, as it can potentially provide high-quality evidence for regulatory decision-making.(5)

On the other hand, while designing a new registry, there are a few general guidelines that need to be considered along with specific ones for a particular regulatory authority. The new registry must have the lowest possible barriers for inclusion, thus maximizing the inclusion of those having the disease/condition to be studied. Different treatment modalities, including drugs, biologics, devices, and combination products, should be considered. Identification of data elements should be performed on the basis of their clinical relevance while maintaining recognized standards and nomenclature. Data collection processes must be systematic, reproducible, reliable, and in accordance with informatics standards. The new registry design should be valid across multiple stakeholder analyses. Finally, a provision should be made to incorporate patient-reported information within the registry.(5)

Appropriately and ethically conducted registry studies can therefore immensely contribute to medical evidence, and prudent regulatory oversight is essential to ensure that the quality of evidence coming from the registry studies is not compromised.

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  1. R. E. Gliklich and N.A. Dreyer, “Registries for Evaluating Patient Registries: A User’s Guide,” Agency for Healthcare Research and Quality, publication No. 07-EHC001 (AHRQ, Rockville, MD, 2007).
  2. Gliklich R. Clinical Trials vs. Registries. April 2009. Available at: https://www.appliedclinicaltrialsonline.com/view/clinical-trials-vs-registries
  3. European Network of Centres for Pharmacoepidemiology and Pharmacovigilance. April 2022. Available at: https://www.encepp.eu/standards_and_guidances/methodologicalGuide4_3.shtml
  4. European Medicines Agency. Guideline on registry-based studies. (EMA/502388/2020) September 2020. Available at: https://www.ema.europa.eu/en/documents/scientific-guideline/guideline-registry-based-studies_en.pdf
  5. Clinical Trials Transformation Initiative (CTTI). CTTI Recommendations: Registry Trials. Available at: https://ctti-clinicaltrials.org/wp-content/uploads/2021/06/CTTI_Registry_Trials_Recs.pdf

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