Biodegradable polymer microparticle containing steroid drug and preparation method therefor

A method for preparing biodegradable polymeric microparticles bearing a steroid drug, the method comprising the steps of:

• (a) dissolving a mixture of a steroid drug and a biodegradable polyester-based polymer in dimethylsulfoxide (DMSO) to prepare a solution containing the steroid drug and the biodegradable polyester-based polymer;
• (b) spraying the solution containing the steroid drug and the biodegradable polyester-based polymer into a C5-10 hydrocarbon solution maintained at a temperature of −10 to −5° C. to form microparticles;
• (c) adding the microparticles to an aqueous salt solution to dissolve and eliminate the DMSO;
• and
• (d) desalting the DMSO eliminated microparticles,
• wherein the mixture of the steroid drug and the biodegradable polyester-based polymer in step (a) comprises the steroid drug and the biodegradable polyester-based polymer at a weight ratio of 1:99 to 3:7 and is dissolved in an amount of 1-25% (w/v) in DMSO, based on the total volume of the solution,
• wherein the C5-10 hydrocarbon solution in step (b) is at least one selected from the group consisting of pentane, hexane, heptane, octane, nonane, decane, and petroleum ether,
• wherein the aqueous salt solution in step (c) is a 5-30% (w/v) solution of NaCl or CaCl2) in water,
• wherein the biodegradable polyester-based polymer is poly(D,L-lactic-co-glycolic acid)(PLGA), and
• wherein the biodegradable polymeric microparticles bearing a steroid drug are spherical porous microparticles having a diameter of 10-100 μm, and steadily release the steroid drug over at least one month.