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  • Administration of Radioactive Substances Advisory Committee (ARSAC)

    Administration of Radioactive Substances Advisory Committee advises the Health Departments on written applications from practitioners for certificates which will enable them to use specific radioactive medicinal products in diagnosis, therapy or research.

  • Admixed embryo

    Embryos produced by somatic cell nuclear transfer: involving the transfer of human nuclei into empty animal egg cells.  The production of human admixed embryos is regulated by the Human Fertilisation and Embryology Authority.

  • Adult stem cells

    Formed from embryonic stem cells they are partially specialized so that they retain the ability to generate a limited number of cell types, but can no longer make all of the different cells in the body.  They replace and replenish cells that are continually lost by depletion or damage e.g. bone marrow, blood, eye, brain and skeletal muscle. Adult stem cells are found in adults, children, babies and the umbilical cord.

  • Advanced therapy medicinal product (ATMP)

    Advanced therapy medicinal products: include gene therapy, stem cell therapy and tissue engineered products (containing some viable cells) exhibiting medicinal function.

  • Adverse Event (AE)

    An adverse event is any undesirable occurrence on a particular study.For clinical trials of investigational medicinal products (CTIMP's) adverse events is defined by ICH GCP as any unfavourable and unintended sign, symptom or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to that product. For other research that does not use investigational products, it may be any unfavourable and unintended sign, symptom or disease temporally associated with participation in the research project.  The term has also been used to describe unfortunate events that may have serious consequences for the research project, e.g. breaking down of a freezer and loss of tissue samples. Alternative terms: Adverse Outcome, Adverse Incident.

  • Amendment

    A change made to the terms of the Research Ethics Committee (REC) application, the protocol or any supporting documentation after the study has started. A study is normally considered to start after the commencement of any protocol procedures. Amendments can be 'substantial' or 'non-substantial'.

  • Animals in Science Committee (ASC)

    Animals in Science Committee (ASC) is an independent non-departmental public body. It is responsible for providing impartial, balanced and objective advice to the Secretary of State (Home Office) and to local animal welfare and ethical review bodies (AWERBs) on issues relating to the Animals (Scientific Procedures) Act and the use of animals in scientific procedures. This advice is not binding.

  • Archiving

    The retention of study files which demonstrate the compliance of the investigator and sponsor with GCP and regulatory requirements; or the retention of valuable research data which may have secondary use or may be analysed further as part of a meta study.

  • Audit

    A systematic and independent examination of study related activities and documents, to determine whether the evaluated study-related activities were conducted, and the data were recorded, analysed and accurately reported according to the protocol, sponsor's standard operating procedures (SOP's), Good Clinical Practice (GCP), and the applicable regulatory requirement(s).

  • Autonomy

    An ethical concept describing an individual's freedom to make decisions and choices that affect them and the lives they lead.