A clinical measure (abbreviated NNT) expressing how many patients must receive a treatment for one additional patient to experience the desired outcome compared to a control group. An NNT of 5 means you need to treat five patients for one to benefit beyond what would happen without treatment.

NNT provides an intuitive way to evaluate treatment effectiveness. An NNT of 2–5 indicates a highly effective treatment; an NNT above 20–50 suggests marginal benefit. Most peptide compounds have not been studied in trials large enough to generate reliable NNT data—this metric requires both a clear outcome definition and a control group, which are absent from the open-label pilots and case series that dominate much of the peptide literature.