Zeolites of a Beta structure with different degrees of substitution of aluminum atoms by those of boron in the aluminum–silicon–oxygen framework have been investigated. The characteristics of the porosity-texture of the fabricated zeolites and the surface properties and sorption capacities of samples to a model drug substance (thiamine hydrochloride) have been examined. It has been demonstrated that isomorphic substitutions could affect the properties of the zeolite under study, whereas the largest effect is associated with the simultaneous presence of aluminum and boron atoms in the zeolite framework. Such samples are characterized with a larger specific area and pore diameters, a high concentration of Lewis acidic sites on the surface, and high adsorption capacity.