grade 4
Life-threatening adverse event classification requiring urgent intervention.
Full Definition
Grade 4 represents life-threatening adverse events in the CTCAE grading system, indicating consequences that are immediately life-threatening and require urgent medical intervention. Grade 4 events typically result in hospitalization, intensive care unit admission, or other urgent medical care to prevent death or permanent disability. These severe toxicities often lead to permanent treatment discontinuation and may require extensive supportive care. In clinical trials, grade 4 events are closely monitored for safety signals and may trigger protocol amendments or study holds.
Usage
Usage note: Grade 4 events always require detailed documentation and expedited reporting in clinical trials.
In Context
- "The patient experienced grade 4 thrombocytopenia requiring platelet transfusion." — Serious adverse event report
- "Grade 4 hepatotoxicity led to permanent treatment discontinuation in three patients." — Clinical trial safety summary