Dose-Limiting Toxicity — What It Means in Clinical Trials
Plain English Definition
A dose-limiting toxicity (DLT) is a side effect that is severe enough to prevent the dose from being increased further. In dose-escalation trials, researchers watch for DLTs to find the highest dose that patients can tolerate. When a DLT occurs, the dose escalation stops or drops back to the previous level.
Why It Matters
DLTs define the safety boundary of a new treatment. If you are in a dose-escalation study, the researchers are carefully monitoring for these events to ensure no one receives a dangerously high dose.
Example
A trial protocol might define: "DLT is defined as any grade 3 or higher non-hematologic toxicity within the first 28 days of treatment."
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