Recommended phase 2 dose (RP2D)
The dose and schedule chosen at the end of a phase 1 trial to test in larger trials, based on safety, blood levels and early signs of activity. It is often, but no longer always, the maximum tolerated dose.
Choosing the RP2D integrates dose-limiting toxicities, pharmacokinetics (whether exposure plateaus), pharmacodynamic target engagement, and responses across dose levels; expansion cohorts then test it in specific tumour types. Because the RP2D usually becomes the approved dose, errors are expensive: too high causes discontinuations and dose reductions in practice, too low wastes efficacy. Under Project Optimus, sponsors are expected to compare two or more doses in randomised cohorts before selecting the RP2D, and to report the proportion of patients needing reductions. Dose changes after approval (via label updates) are increasingly common.
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not linked directly; found by shared links- TermTherapeutic index (therapeutic window)
Shares Pharmacokinetics (PK), half-life and exposure, Dose-limiting toxicity (DLT), Maximum tolerated dose (MTD), Project Optimus.
- TermFirst-in-human (FIH) trial
Shares Dose-escalation designs (3+3, BOIN, dose-expansion), Maximum tolerated dose (MTD).
- TermDose reduction, interruption and discontinuation
Shares Pharmacokinetics (PK), half-life and exposure, Maximum tolerated dose (MTD), Project Optimus.