Abstract: The present invention relates to a composition for storing a liquid formulation of botulinum toxin for a long period of time at a low temperature and, more specifically, to a liquid-phase pharmaceutical composition and a method for maintaining biological activity of botulinum toxin by using same, wherein the composition comprises, as active ingredients, (i) botulinum toxin, (ii) hyaluronic acid or a pharmaceutically acceptable salt thereof, and (iii) one or more additives selected from the group consisting of saccharides, a non-ionic surfactant, and a stabilizer. The composition according to the present invention has a remarkable effect of physically and chemically stabilizing botulinum toxin and preventing the tertiary structure of botulinum toxin from denaturing, thus making it possible to expand the formulation of botulinum toxin from conventionally limited dry agents to liquid-phase agents.

Abstract: Disclosed is a method for preparing sustained release microparticles which release a physiologically active substance for long periods of time. The sustained release microparticles are prepared through a multi-emulsion process. A drug of interest is dissolved or dispersed in each of at least two oils to give at least two primary oil phases or emulsions. Each oil phase or emulsion contains a biodegradable polymer. The least two primary oil phases or emulsions are dispersed in one aqueous phase, synchronously or in succession. From the drug-dispersed solution, the organic solvents are removed to produce microparticles. Therefore, the drugs such as leutenizing hormone releasing hormones can be continuously released in vivo for prolonged periods of time, bringing about an improvement in the therapeutic effect.