Maximum Tolerated Dose — What It Means in Clinical Trials
Plain English Definition
The maximum tolerated dose (MTD) is the highest dose of a drug that does not cause unacceptable side effects. It is determined through dose-escalation trials where each group receives a progressively higher dose. When too many patients experience dose-limiting toxicities, the dose just below that level becomes the MTD.
Why It Matters
The MTD helps determine what dose will be used in future, larger trials. If you are in a dose-escalation study, you are helping establish this important threshold for the benefit of future patients.
Example
A study conclusion might say: "The maximum tolerated dose was determined to be 400mg daily. This dose will be used in the Phase 2 expansion cohort."
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