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USFDA Guidance: GASK in Drug & Biologics: Nonclinical Info & Slide Imaging in Nonclinical Toxicology

Earlier today (25 May, 2023) the United States Food & Drug Administration released two guidelines "Generally Accepted Scientific Knowledge in Applications for Drug and Biological Products: Nonclinical Information" and guidance "Use of Whole Slide Imaging in Nonclinical Toxicology Studies: Questions and Answers".

GASK is a term used to describe medical or scientific information that has generally been accepted by experts with scientific training and experience in the relevant field, including FDA experts. GASK is typically based on well-established scientific principles that have been widely accepted for decades.

As part of this guidance, GASK may be used to meet certain nonclinical safety requirements for new drug applications (NDAs) submitted under section 505(b) of the Federal Food, Drug, and Cosmetic Act and biologic license applications (BLAs) submitted under section 351 of the Public Health Service Act.

As part of the application, information supporting the nonclinical safety of a drug can include references to GASK, when appropriate, in addition to or instead of specific studies conducted on the drug.

Whole slide imaging includes the software and hardware used to generate a two-dimensional digital image of a glass histology slide used for routine assessment in the generation of the pathology report.

A whole slide image used in a GLP-compliant study should include all the elements of a glass slide necessary for histopathological examination and pathology peer review.

There are four sequential steps involved in the process:

  1. the acquisition of images (scanning),

  2. the processing of images,

  3. the storage of images, and

  4. the presentation of images.

In this guidance, sponsors and nonclinical laboratories are provided with information on how to manage and use whole slide images for histopathology assessment and/or pathology peer review as part of good laboratory practice (GLP)-compliant nonclinical toxicology studies using nonhuman samples.

The purpose of this guidance is to clarify FDA's recommendations on the management, documentation, and use of whole slide imaging in nonclinical studies that comply with GLP guidelines for histopathology assessment and/or pathology peer review.


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