Thermoreversible pharmaceutical formulation for anti-microbial agents comprising poloxamer polymers and hydroxy fatty acid ester of polyethylene glycol

A pharmaceutical formulation having a thermoreversible property, comprising:

• a) clindamycin phosphate;
• b) a poloxamer mixture containing a first poloxamer polymer and a second poloxamer polymer, wherein the first poloxamer polymer and the second polaxamer polymer are not the same, and wherein the first poloxamer polymer is poloxamer 407 and the second poloxamer polymer is poloxamer 188;
• and
• c) polyethylene glycol 660 hydroxystearate,
• wherein the pharmaceutical formulation having a viscosity of about 8,500 cP to about 400,000 cP at room temperature, a viscosity of about 1,000 cP to about 8,000 cP at body temperature, and exhibiting a hysteresis loop behavior.

A process of preparing a pharmaceutical formulation having a thermoreversible property, comprising the steps of:

• a) preparing a poloxamer mixture containing at least a first poloxamer and a second poloxamer polymer;
• b) preparing a molten solution of hydroxy fatty acid ester of polyethylene glycol;
• c) adding the poloxamer mixture to the molten solution of hydroxy fatty acid ester of polyethylene glycol;
• and
• d) adding an anti-microbial agent to form a thermoreversible pharmaceutical formulation.