{
  "url": "https://openlegislation.uk/medicines-for-human-use-clinical-trials-regulations-2004/regulation-33",
  "json_url": "https://openlegislation.uk/medicines-for-human-use-clinical-trials-regulations-2004/regulation-33.json",
  "legislation": "uksi/2004/1031",
  "legislation_title": "The Medicines for Human Use (Clinical Trials) Regulations 2004",
  "legislation_url": "https://openlegislation.uk/medicines-for-human-use-clinical-trials-regulations-2004",
  "path": "regulation/33",
  "kind": "regulation",
  "number": "33",
  "heading": "Notification of suspected unexpected serious adverse reactions",
  "text": "(1) A sponsor shall ensure that all relevant information about a suspected unexpected serious adverse reaction which occurs during the course of a clinical trial in the United Kingdom and is fatal or life-threatening is reported as soon as possible to the licensing authority, and in any event no later than 7 days after the sponsor was first aware of the reaction.\n(2) A sponsor shall ensure that within 8 days of a report in accordance with paragraph (1), any additional relevant information is sent to the licensing authority.\n(3) A sponsor shall ensure that a suspected unexpected serious adverse reaction which occurs during the course of a clinical trial in the United Kingdom, other than those referred to in paragraph (1), is reported as soon as possible to the licensing authority, and in any event no later than 15 days after the sponsor is first aware of the reaction.\n(4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n(4A) Paragraphs (1) to (3) do not apply to suspected unexpected serious adverse reactions specified in the protocol as not requiring immediate reporting.\n(4B) The sponsor shall report suspected unexpected serious adverse reactions to which paragraph (4A) applies to the licensing authority in accordance with the reporting requirements, including the time periods for such reporting, that are specified in the protocol.\n(5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n(6) The licensing authority shall—\n(a) keep a record of all suspected unexpected serious adverse reactions relating to an investigational medicinal product which are brought to its attention, whether pursuant to paragraphs (1) or (3) or otherwise; and\n(b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Reg. 33(1) substituted (28.4.2026) by The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(2)"
    },
    {
      "type": "F",
      "label": "F2",
      "text": "Words in reg. 33(2) substituted (28.4.2026) by The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(3)(a)"
    },
    {
      "type": "F",
      "label": "F3",
      "text": "Words in reg. 33(2) substituted (28.4.2026) by The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(3)(b)"
    },
    {
      "type": "F",
      "label": "F4",
      "text": "Reg. 33(3) substituted (28.4.2026) by The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(4)"
    },
    {
      "type": "F",
      "label": "F5",
      "text": "Reg. 33(4) omitted (31.12.2020) by virtue of The Medicines for Human Use (Clinical Trials) (Amendment) (EU Exit) Regulations 2019 (S.I. 2019/744), regs. 1, 14(4); 2020 c. 1, Sch. 5 para. 1(1)"
    },
    {
      "type": "F",
      "label": "F6",
      "text": "Reg. 33(4A)(4B) inserted (28.4.2026) by The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(5)"
    },
    {
      "type": "F",
      "label": "F7",
      "text": "Reg. 33(5) omitted (28.4.2026) by virtue of The Medicines for Human Use (Clinical Trials) (Amendment) Regulations 2025 (S.I. 2025/538), regs. 1(2), 25(6)"
    },
    {
      "type": "F",
      "label": "F8",
      "text": "Reg. 33(6)(b) and word omitted (31.12.2020) by virtue of The Medicines for Human Use (Clinical Trials) (Amendment) (EU Exit) Regulations 2019 (S.I. 2019/744), regs. 1, 14(5); 2020 c. 1, Sch. 5 para. 1(1)"
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/2004/1031/regulation/33",
    "retrieved_at": "2026-10-29T05:28:03.775386+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}