Prior Therapy — What It Means in Clinical Trials
Plain English Definition
Prior therapy refers to any treatments you have already received for your condition before joining a trial. Many trials specify how many prior treatments you must have tried (and not responded to) in order to qualify. Some trials require no prior therapy, while others require you to have tried at least one or two treatments first.
Why It Matters
Your treatment history directly affects which trials you qualify for. Keep a record of every treatment you have received, including the drug names, doses, and how long you were on each one.
Example
A listing might say: "Must have received at least 2 prior lines of systemic therapy" or "No prior treatment with PD-1 inhibitors."
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