Liposomes encapsulating adenosine

1. An injectable formulation comprising saline and liposomes comprising one or more lamellae, wherein the liposome lamellae comprise 70 to 100% by mass sphingomyelin and when there is less than 100% by mass sphingomyelin the remainder is 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) or 1,2-dimyristoyl-sn-glycero-3-phosphorylglycerol (DMPG) or DMPC and DMPG together, wherein the liposomes

(a) have a diameter of 50 nm to 150 μm; and

(b) encapsulate adenosine in the aqueous compartment of the liposome, wherein the concentration of adenosine is 3 mg/mL.

2. The injectable formulation of claim 1 , wherein the adenosine or a portion thereof is released for up to two weeks.

3. The injectable formulation of claim 1 , further comprising an excipient.

4. The injectable formulation of claim 1 , wherein the formulation is suitable for intra-articular injection.

5. The injectable formulation of claim 1 , wherein the ratio of DMPC and DMPG is from 6:4 to 8:2.

6. The injectable formulation of claim 5 , wherein the ratio of DMPC and DMPG is 7:3.

7. The injectable formulation of claim 1 , wherein the total lipid concentration is 7 to 12 mg/mL.

8. The injectable formulation of claim 1 , wherein one or more of the liposomes have a diameter of 50 nm to 100 μm.

9. The injectable formulation of claim 1 , wherein one or more of the liposomes have a diameter of 100 nm to 150 μm.

10. The injectable formulation of claim 1 , wherein the liposomes collapse at a temperature of 35 to 45° C.

11. The injectable formulation of claim 1 , wherein at least a portion of the adenosine is released within 1 second to 1 hour of administration to a joint of an individual.

12. The injectable formulation of claim 11 , wherein at least a portion of the adenosine is released within 1 minute to 1 hour of administration to the joint of the individual.

13. The injectable formulation of claim 12 , wherein at least 1 to 20% of the adenosine is released within 1 minute to 1 hour of administration to the joint of the individual.

14. The injectable formulation of claim 11 , wherein at least a portion of adenosine or at least 1 to 20% of adenosine is released within 1 second to 10 minutes of administration to the joint of the individual.

15. The injectable formulation of claim 1 , wherein the liposomes have a diameter of 50 nm to 1 μm.

16. The injectable formulation of claim 1 , wherein the liposomes have a diameter of 1 μm to 150 μm.

17. The injectable formulation of claim 1 , wherein the liposome lamellae comprise 75 to 100% by mass sphingomyelin.

18. A method of i) inducing cartilage regeneration and/or ii) alleviating joint pain and/or inflammation and/or iii) slowing and/or arresting and/or reversing progressive structural tissue damage comprising administering to an individual an injectable formulation of claim 1 , wherein i) cartilage regeneration is induced and/or ii) joint pain and/or inflammation is alleviated or partially alleviated and/or iii) progressive structural tissue damage is slowed or partially slowed and/or arrested or partially arrested and/or is reversed or partially reversed.

19. The method of claim 18 , wherein the injectable formulation is administered via intra-articular injection to a joint of the individual.

20. The method of claim 18 , wherein the injectable formulation is administered in one or more injections.

21. The method of claim 18 , wherein the injectable formulation is administered multiple times, wherein each administration occurs once every 10 days.

22. The method of claim 18 , wherein the individual has osteoarthritis, rheumatoid arthritis, acute gouty arthritis, and/or synovitis.

23. The method of claim 19 , wherein the individual is a human or a non-human mammal.