Alpha polyglutamated methotrexate and uses thereof

1. A liposomal composition comprising a liposome encapsulating an alpha polyglutamated methotrexate containing 4, 5, 6, 4-6, or 4-10 glutamyls having alpha carboxyl group linkages, wherein the liposome is pegylated, wherein the liposome does not contain a targeting moiety having specific affinity for a surface antigen on a target cell,

wherein the liposome does not contain a cell penetrating peptide and does not contain a mitochondria penetrating peptide,

wherein the liposome has a zeta potential that is less than or equal to zero, between 0 to −150 mV, or between −30 to −50 mV, and

wherein the liposome is capable of delivering the alpha polyglutamated methotrexate directly into a cell.

2. The liposomal composition of claim 1 wherein:

(a) at least 2 of the glutamyl groups of the alpha polyglutamated methotrexate are in the L-form,

(b) each of the glutamyl groups of the alpha polyglutamated methotrexate is in the L-form,

(c) at least 1 of the glutamyl groups of the alpha polyglutamated methotrexate is in the D-form,

(d) each of the glutamyl groups of the alpha polyglutamated methotrexate other than the glutamyl group of methotrexate is in the D-form, or

(e) at least 2 of the glutamyl groups of the alpha polyglutamated methotrexate are in the L-form and at least 1 of the glutamyl groups is in the D-form.

3. The liposomal composition of claim 1 , wherein the liposome comprises an alpha tetraglutamated methotrexate.

4. The liposomal composition of claim 1 , wherein the liposome comprises an alpha pentaglutamated methotrexate.

5. The liposomal composition of claim 1 , wherein the liposome comprises an alpha hexaglutamated methotrexate.

6. The liposomal composition of claim 1 , wherein the alpha polyglutamated methotrexate is linear or branched.

7. The liposomal composition of claim 1 , wherein the liposome has a diameter in the range of 20 nm to 500 nm, 20 nm to 200 nm, or 80 nm to 120 nm.

8. The liposomal composition of claim 1 , wherein the liposome is formed from liposomal components comprising: at least one of an anionic lipid and a neutral lipid; at least one selected from: DSPE; DSPE-PEG; DSPE-PEG-maleimide; HSPC; HSPC-PEG; cholesterol; cholesterol-PEG; and cholesterol-maleimide; or

at least one selected from: DSPE; DSPE-PEG; DSPE-PEG-FITC; DSPE-PEG-maleimide; cholesterol; and HSPC.

9. The liposomal composition of claim 8 , wherein one or more liposomal components further comprise at least one steric stabilizer selected from: poly(vinyl pyrrolidone) (PVP); poly(acrylamide) (PAA); poly(2-methyl-2-oxazoline); poly(2-ethyl-2-oxazoline); phosphatidyl polyglycerol; poly[N-(2-hydroxypropyl) methacrylamide]; amphiphilic poly-N-vinylpyrrolidones; L amino-acid-based polymer; oligoglycerol, copolymer containing polyethylene glycol and polypropylene oxide, Poloxamer 188, and polyvinyl alcohol.

10. The liposomal composition of claim 1 , wherein the liposome has an interior space comprising the alpha polyglutamated methotrexate and an aqueous pharmaceutically acceptable carrier comprising:

a tonicity agent at a concentration of greater than 1%;

1% to 50% trehalose;

1% to 50% dextrose;

5% dextrose suspended in an HEPES buffered solution; or

a total concentration of sodium acetate and calcium acetate of between 50 mM to 500 mM.

11. The liposomal composition of claim 10 , wherein the interior space of the liposome has a pH of 5-8 or a pH of 6-7, or any range therein between.

12. The liposomal composition of claim 1 , wherein the liposome comprises between 10 to 500,000, between 10 to 200,000, or between 10 to 100,000 molecules of the alpha polyglutamated methotrexate, or any range therein between.

13. The liposomal composition of claim 1 , which further comprises at least one cryoprotectant selected from mannitol; trehalose; sorbitol; and sucrose.

14. The liposomal composition of claim 1 , which further comprises carboplatin and/or pembrolizumab.

15. The liposomal composition of claim 1 , wherein the alpha polyglutamated methotrexate contains 4-6 glutamyls having alpha carboxyl group linkages.

16. A pharmaceutical composition comprising the liposomal composition of claim 1 .

17. A method of killing a hyperproliferative cell that comprises contacting a hyperproliferative cell with the liposomal composition of claim 1 .

18. The method of claim 17 , wherein the hyperproliferative cell is a cancer cell, a mammalian cell, and/or a human cell.

19. A method for treating cancer that comprises administering an effective amount of the liposomal composition of claim 1 to a subject having cancer.

20. The method of claim 19 , wherein the cancer is selected from: a non-hematologic malignancy, lung cancer, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, head and neck cancer, gastric cancer, gastrointestinal cancer, colorectal cancer, esophageal cancer, cervical cancer, liver cancer, kidney cancer, biliary duct cancer, gallbladder cancer, sarcoma, osteosarcoma, soft-tissue sarcoma, brain cancer, central nervous system cancer, melanoma, a hematologic malignancy, a leukemia, a lymphoma, B cell malignancies, myeloma, plasma cell dyscrasias, Non-Hodgkin's lymphoma (NHL), acute lymphoblastic leukemia (ALL), chorioadenoma, mycosis fungoides choriocarcinoma, cutaneous T-cell lymphoma, nonleukemic meningeal cancer, desmoid tumors, bladder cancer, central Nervous System (CNS) lymphoma; mesothelioma, and non-small cell lung carcinoma (NSCLC).

21. A method of preparing an alpha polyglutamated methotrexate composition comprising the liposomal composition of claim 1 , the method comprising: forming a mixture comprising: liposomal components and alpha polyglutamated antifolate in solution; homogenizing the mixture to form liposomes in the solution; and processing the mixture to form liposomes containing alpha polyglutamated methotrexate.