When Is Rechallenge Not Applicable?

Hello, For assessment of Rechallenge values with the safety database, should a user consider the treatment intervention provided to the patient? For assessment of Dechallenge values, if treatment is provided (corrective medication for the event), then Dechallenge is considered Not Applicable.

When is dechallenge not applicable?

For example, the concept of dechallenge may not be applicable where the drug is a one-dose treatment (e.g., vaccine), reaction resulting in death and reaction occurring after discontinuation of drug.

What is dechallenge and rechallenge in clinical trials?

The Food and Drug Administration of the United States lists positive dechallenge reactions (an adverse event which disappears on withdrawal of the medication) as well as negative (an adverse event which continues after withdrawal), as well as positive rechallenge (symptoms re-occurring on re-administration) and ...