Extended release microparticles and suspensions thereof for medical therapy

A method for the treatment of an ocular disorder selected from glaucoma, wet-age related macular degeneration, dry-age related macular degeneration, or a disorder related to an increase in intraocular pressure comprising suprachoroidal administration of an effective amount of solid aggregating biodegradable microparticles optionally in a pharmaceutically acceptable carrier wherein the solid aggregating biodegradable microparticles comprise a therapeutic agent encapsulated in (a) poly(lactic-co-glycolic acid) (PLGA) and/or polylactic acid (PLA) and (b) poly(lactic-co-glycolic acid) conjugated to polyethylene glycol (PLGA-PEG), and a surfactant, wherein the microparticles:

• (i) have a mean diameter between 10 μm and 60 μm;
• (ii) have been surface-modified with a surface treatment agent to partially degrade surface polymer at a temperature less than about 18° C. wherein the surface treatment agent comprises an aqueous base and an organic solvent;
• (iii) aggregate in vivo to form at least one larger pellet in vivo that provides sustained drug delivery in vivo for at least three months;
• and
• (iv) wherein the therapeutic agent is sunitinib or a pharmaceutically acceptable salt thereof.