Prequalification of LV potency assay. Mock potency samples were prepared with relative potencies between 50% and 150% of the reference standard and then used in the LV potency assay. JMP17® software was used to fit 4PL curves, test for parallelism (F test), and calculate the measured relative potency of each sample. (a) Representative data from one of three independent experiments. Error bars indicate a standard deviation of n = 3 replicates. (b) Analysis of assay linearity based on pooled average recovery from all three experiments.