Microparticle formulations of adenosine receptor antagonists for treating cancer

Abstract

The invention provides compositions comprising microparticles wherein the microparticles comprise at least one adenosine 2a receptor antagonist (A2ARA), at least one pharmaceutically acceptable polymer and at least one pharmaceutically acceptable negatively charged agent wherein the microparticles optionally have a highly negative zeta potential of less than about −40 mV. The invention also provides pharmaceutical compositions of the microparticles of the invention and methods of using the compositions of the invention to enhance an immune response in a patient in need thereof and as anti-cancer immunotherapy.

What is claimed is: 
     
         1 . A composition comprising microparticles wherein the microparticles comprise at least one adenosine 2a receptor antagonist (A2ARA), at least one pharmaceutically acceptable polymer and optionally at least one pharmaceutically acceptable negatively charged agent wherein the microparticles have a negatively charged surface. 
     
     
         2 . The composition of  claim 1 , wherein the at least one pharmaceutically acceptable polymer is PLGA. 
     
     
         3 . The composition of  claim 1  comprising at least one pharmaceutically acceptable negatively charged agent. 
     
     
         4 . A method of treating cancer in a subject in need thereof comprising administering an effective amount of the microparticle composition of  claim 1 . 
     
     
         5 . A method of enhancing an immune response in a patient in need thereof, said method comprising administering a therapeutically effective amount of an A2ARA microparticle composition of  claim 1  to a patient. 
     
     
         6 . The method of  claim 4 , wherein the patient is in need of immunotherapy for the treatment of cancer. 
     
     
         7 . The method of  claim 1 , wherein the zeta potential of the microparticles is about −25 mV or lower. 
     
     
         8 . The method of  claim 1 , wherein the zeta potential of the microparticles is about −35 mV or lower. 
     
     
         9 . The method of  claim 4 , further comprising administering a checkpoint inhibitor, chemotherapy, radiation, or any combination thereof. 
     
     
         10 . A method of treating a cancerous tumor comprising the step of intratumorally injecting or intratum orally implanting the microparticles of  claim 1 . 
     
     
         11 . A method of treating a cancerous tumor comprising the step of injecting the microparticles of  claim 1  into the tumor microenvironment. 
     
     
         12 . A method of sustained delivery of A2ARA to a tumor microenvironment comprising the step of injecting the microparticles of  claim 1  into the tumor microenvironment. 
     
     
         13 . The composition of  claim 1 , wherein the effective particles size of the microparticles are about 1 nm to about 10 μm. 
     
     
         14 . The composition of  claim 13 , wherein the effective particle size of the microparticles is selected from 10 microns or lower, 5 microns or lower, 3 microns or lower, 2 microns or lower, 900 nm or lower, 700 nm or lower, 600 nm or lower and 500 nm or lower. 
     
     
         15 . The composition of  claim 1  formulated for administration to a subject orally, rectally, ocularly, parenterally, intracisternally, intracranially, pulmonarily, intravaginally, intraperitoneally, topically, intratumorally, by injection into the tumor microenvironment, buccally or by nasal spray.