Polyphenol compounds consisting of caffeic acid oligomers were detected in cell cultures from Eritrichium sericeum Lehm.: (−)-rabdosiin, (+)-rosmarinic acid, and eritrichin; the quantitative contents of individual polyphenols were determined. The total content of polyphenol compounds in biotechnological raw material was 6.9% of dry tissue weight, which was 26.5 times greater than the content in the roots of the native plant. Studies of the pharmacological activity of the experimental Eritrichium sericeum Lehm. preparation, containing a complex of polyphenol compounds, demonstrated increases in renal excretory function and suppression of the exudative stage of inflammation as a result of prolonged use of the cell culture phytocomplex at a dose of 100 mg/kg.