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    Serious Adverse Event

    Adverse event resulting in death, life-threat, hospitalization, persistent disability, or congenital anomaly.

    Reviewed by Christian Espinosa, Founder, Blue Goat CyberLast reviewed May 5, 2026

    Definition

    An SAE per ISO 14155 is any AE that led to death; serious deterioration in health resulting in life-threatening illness or injury, permanent impairment, in-patient hospitalization, or medical/surgical intervention; or fetal distress or congenital anomaly. Serious adverse events must be reported promptly. Under MDR Article 80 and MDCG 2020-10/1, sponsors report reportable SAEs to the competent authorities of all member states running the investigation, within set timeframes as short as two days for events suggesting imminent risk. In the US, unanticipated adverse device effects must reach FDA and IRBs within 10 working days under 21 CFR 812.150.
    What the regulation says
    Regulators such as FDA and notified bodies under EU MDR, and standards like ISO 14155, mandate strict reporting requirements for Serious Adverse Events. These requirements ensure that any significant safety concerns arising during clinical investigations are promptly communicated to safeguard participant well-being and inform regulatory decision-making regarding device safety and efficacy.

    What this means in practice

    Sponsors must report SAEs and SADEs to regulators and IRBs/ECs within defined timeframes (often 7 or 15 days depending on jurisdiction and seriousness).

    Examples

    • A participant in a clinical trial for a novel cardiac stent experiences a myocardial infarction leading to emergency hospitalization, which is classified as a Serious Adverse Event.
    • A subject using an investigational continuous glucose monitor develops severe hypoglycemia requiring intervention, meeting the definition of a Serious Adverse Event due to serious deterioration in health.
    • During a clinical study, a participant succumbs to an unforeseen illness unrelated to the investigational device, but because it resulted in death, it is still reported as a Serious Adverse Event by the study sponsor.
    Common pitfalls
    • •Confusing a Serious Adverse Event with an Adverse Event, which has different reporting criteria.
    • •Failing to report a Serious Adverse Event within the mandated timeframe, leading to non-compliance.
    • •Misinterpreting the criteria for "serious deterioration in health" or "life-threatening illness or injury."
    • •Not having a clear internal procedure for identifying, documenting, and reporting Serious Adverse Events.
    • •Failing to track all required data elements for a Serious Adverse Event report.

    Frequently asked questions

    An Adverse Event (AE) is any untoward medical occurrence, while a Serious Adverse Event (SAE) specifically meets criteria indicating a serious outcome like death, life-threatening illness, or permanent impairment, as defined by ISO 14155.

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    Sources

    3 sources

    Sources support the definition or relevant regulatory context, not necessarily every claim on this page. Each is graded against our source-tier hierarchy so you can see what rests on binding law versus commentary.

    Tier 1Binding law and standards· 1Tier 2Regulator guidance and consensus· 1Tier 3Peer-reviewed and registry evidence· 1
    Link health: 3 verified· last checked 2026-06-20
    ISO·1FDA·1NIH·1
    1. 1
      ISO 14155:2020
      Tier 1 Verified
      ISOiso.org
    2. 2
      FDA - Clinical Trials and Human Subject Protection
      Tier 2 Verified
      FDAfda.gov
    3. 3
      ClinicalTrials.gov
      Tier 3 Verified
      NIHclinicaltrials.gov

    Inline markers like [1] jump to the matching reference above.