Bioactivity Determination of Native and Variant Forms of Therapeutic Interferons

Table 3

Relative potency of IFN-β as determined by RGA.

IFN-β samples (%)	Mean estimated potency	Relative to assessment (%)	Lower and upper limits (95% CI) (%)
80	25875.9	86.8%	79.4–94.9
100	32462.7	108.9%	99.6–119.1
120	34193.8	114.7%	104.9–125.5

The IFN-β samples were pre-determined by AVA, followed by spiking into media at 80, 100, and 120% of the expected values. The “spiked” samples were then subjected to RGA analyses in comparison with the reference standards.