Partial Response — What It Means in Clinical Trials
Plain English Definition
A partial response (PR) means the disease has shrunk significantly but has not completely disappeared. In cancer trials, a partial response typically means tumors have decreased by at least 30% in size. While not as good as a complete response, a partial response indicates the treatment is working.
Why It Matters
A partial response is still a positive outcome. It means the treatment is active against your disease, and continued treatment might lead to further improvement.
Example
A trial report might state: "Partial response seen in 35% of participants, with tumors shrinking by 30-80% from baseline."
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