Primary Endpoint
The main outcome measure in a clinical trial that the study is specifically designed and powered to evaluate. For GLP-1 receptor agonist diabetes trials, the primary endpoint is typically HbA1c change; for weight management trials, it is percentage body weight change.
Technical Context
The primary endpoint determines the trial's sample size calculation, statistical analysis plan, and regulatory conclusion. It must be pre-specified, clinically meaningful, measurable, and achievable within the trial duration. For diabetes trials: change in HbA1c from baseline at 24-52 weeks. For weight management trials: percentage change in body weight from baseline AND proportion achieving ≥5% weight loss (co-primary endpoints). For cardiovascular outcomes trials: time to first MACE (3-point: CV death, non-fatal MI, non-fatal stroke). For cancer trials: overall survival or progression-free survival. The FDA and EMA may have different preferred primary endpoints for the same condition, requiring sponsors to pre-plan analyses acceptable to both agencies.