A U.S. Patent for a “Process and System for Obtaining Botulinum Neurotoxin” was awarded to Allergan on November 5th, 2019. The present invention is a process for producing a biologically active botulinum neurotoxin, the method comprising the following steps: providing a fermentation medium which is free of animal-derived products; fermenting Clostridium botulinum bacteria in the fermentation medium; contacting the fermentation medium with an anion exchange chromatography medium; then contacting an eluate of the anion exchange chrom medium with a cation exchange chromatography medium; and eluting an eluate. Learn More