Аннотация:Vitamin B12 is a vital biologically active compound for human and is involved in a wide range of metabolicprocesses. The widespread vitamin B12 deficiency and vitamin’s low penetrating ability into cells determinethe urgency of delivery systems development for the design of formulations with improved biopharmaceuticalproperties. This work provides a brief discussion of the main chemical and biochemical properties of the vitaminB12, as well as considers oral, injectable and transdermal multicomponent dosage forms of vitamin B12 that areaimed at solving the issue. Moreover, the literature analysis of the prospects of using vitamin B12 as an auxiliarycomponent for both passive and active delivery of other drug molecules, for example, peptide nucleic acids andantitumor drugs, is presented. The review describes in detail the types of proposed delivery systems for biologicallyactive compounds, in which vitamin B12 is one of the components.