Thank you for your email and question.
There are a few differences between the Vegan AminoBoostXXL and regular AminoBoostXXL. The Leucine in the regular AminoBoostXXL is derived from duck feathers and the other 7 amino acids from microbial fermentation while the Vegan AminoBoostXXL uses microbial fermentation for all 8 amino acids. There is a significant cost saving when deriving the Leucine from duck feathers, hence the increased cost of the vegan formula.
Other differences are the sweeteners and flavor package which are all natural in the Vegan AminoBoostXXL. We use Stevia and Raw Cane Sugar in the Vegan AminoBoostXXL and thus the reason the higher calorie count per serving (70 calories).