What Is ORR in Clinical Trials? Objective Response Rate Explained

What is ORR (Objective Response Rate) in clinical trials?

Objective response rate (ORR) is the proportion of participants whose tumour shrank by a predefined amount. It is the sum of complete responses and partial responses, divided by the number of evaluable participants. Stable disease is excluded. ORR answers one question, at one point in time: did the treatment produce measurable tumour shrinkage in this […]

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