Cobalok™ is a value-added biopharmaceutical ingredient complex consisting of vitamin B12 as hydroxocobalamin (OHCbl) pre-bound to its natural binding protein, intrinsic factor.
The intrinsic factor used in Cobalok™ is a recombinant form of human intrinsic factor (rhIF) that was transgenically expressed in the plant Arabidopsis thaliana. The rhIF contains an exact 100% match in its genomic sequence to human IF and has demonstrated equivalent B12 binding and superior cubilin receptor binding when compared with native human IF.
Intrinsic factor protein attaches to the vitamin B12 molecule in a 1:1 molecular ratio (see ribbon diagram of intrinsic factor bound to cobalamin with the Cbl molecule shown in ball and stick). Thus, the amount of intrinsic factor pre-bound to OHCbl in Cobalok™ is determined by the ratio between the two molecular masses, which calculates to a coefficient of proportionality of approximately 37. For every 1 mcg of OHCbl in Cobalok™, approximately 37 mcg of rhIF will be pre-bound.
Cobalok™ will be offered as an active pharmaceutical ingredient (API) granulate for use in products formulated to deliver vitamin B12 in oral dosage forms.