Drug loaded polymeric nanoparticles and methods of making and using same

1. A therapeutic nanoparticle comprising:

about 5 to about 30 weight percent of a therapeutic agent;

about 10 to about 99 weight percent of a diblock poly(lactic) acid-poly(ethylene)glycol copolymer, wherein said poly(lactic) acid-poly(ethylene)glycol copolymer comprises poly(lactic acid) having a number average molecular weight of about 15 to 20 kDa and poly(ethylene)glycol having a number average molecular weight of about 4 to about 6 kDa; and

wherein the hydrodynamic diameter of the therapeutic nanoparticle is about 70 to about 130 nm; and wherein the therapeutic nanoparticle releases less than 10% of the therapeutic agent over about one minute when placed in a phosphate buffer solution at 37° C.

2. The therapeutic nanoparticle of claim 1 wherein said therapeutic agent is a taxane.

3. The therapeutic nanoparticle of claim 1 , wherein the hydrodynamic diameter is about 70 to about 120 nm.

4. The therapeutic nanoparticle of claim 1 , wherein the therapeutic nanoparticle substantially retains the therapeutic agent for at least 5 days at 25° C.

5. The therapeutic nanoparticle of claim 2 , comprising about 10 to about 20 weight percent of the taxane.

6. The therapeutic nanoparticle of claim 1 , comprising about 40 to about 90 weight percent diblock poly(lactic) acid-poly(ethylene)glycol copolymer.

7. The therapeutic nanoparticle of claim 1 , wherein the particle releases less than about 5% of the therapeutic agent over 1 hour when placed in a phosphate buffer solution at room temperature.

8. The therapeutic nanoparticle of claim 1 , wherein the particle releases less than about 10% of the therapeutic agent over 24 hours when placed in a phosphate buffer solution at room temperature.

9. The therapeutic nanoparticle of claim 1 , further comprising about 0.2 to about 10 mole percent PLA-PEG-GL2, wherein GL2 is represented by the formula:

10. The therapeutic nanoparticle of claim 1 , further comprising a polymeric compound represented by:

where y is about 222 and z is about 114.

11. The therapeutic nanoparticle of claim 1 , wherein said poly(ethylene)glycol has a number average molecular weight of about 5 kDa.

12. The therapeutic nanoparticle of claim 2 , wherein said taxane is docetaxel.

13. A method of treating prostate or breast cancer comprising administering to a patient in need thereof an effective amount of the therapeutic nanoparticle of claim 2 .

14. A pharmaceutical composition comprising:

a plurality of polymeric nanoparticles each comprising about 5 to about 30 weight percent of a therapeutic agent, about 70 to about 99 weight percent of a biocompatible polymer, wherein the biocompatible polymer is selected from the group consisting of: a) poly(lactic) acid-poly(ethylene)glycol copolymer, wherein said poly(lactic) acid-poly(ethylene)glycol copolymer comprises poly(lactic acid) having a number average molecular weight of about 16 kDa and poly(ethylene)glycol having a number average molecular weight of about 5 kDa; and b) a combination of a) and poly (lactic) acid; and

a pharmaceutically acceptable excipient;

wherein the hydrodynamic diameter of the polymeric nanoparticle is about 70 to about 130 nm; and wherein the polymeric nanoparticle releases less than 10% of the therapeutic agent over about one minute when placed in a phosphate buffer solution at 37° C.

15. The composition of claim 14 comprising less than about 10 ppm of palladium.

16. The pharmaceutical composition of claim 14 , wherein the pharmaceutically acceptable excipient is sucrose.

17. A therapeutically acceptable nanoparticle suitable for treating a solid tumor, comprising:

wherein y is about 222 and z is about 114; and about 5 to about 25 weight percent taxane;

wherein the hydrodynamic diameter of the therapeutically acceptable nanoparticle is about 70 to about 130 nm.