Lipid aggregates for intraarticular administration

Abstract

Disclosed is a composition, a composition comprising an anionic lipid composition and a polycationic aggregation agent for use in the intraarticular treatment of a joint disease or disorder, for example osteoarthritis. Also disclosed are kits for making the composition and novel compositions comprising an anionic lipid composition and a polycationic aggregation agent.

Description

LIPID AGGREGATES FOR INTRAARTICULAR ADMINISTRATION

[0001] The present invention relates to a composition comprises an anionic lipid composition and a polycationic aggregation agent for use in the intraarticular treatment of a joint disease or disorder, for example osteoarthritis. Suitably, the composition comprises aggregates comprising the anionic lipid composition and the polycationic aggregation agent. The invention also relates kits for making the composition and to novel compositions comprising an anionic lipid composition and a polycationic aggregation agent.BACKGROUND OF THE INVENTION

[0002] Osteoarthritis (OA) is a persistent joint condition affecting over 500 million people worldwide, with significant costs to the healthcare system. The pathogenesis of OA involves mechanical, inflammatory, fibrotic, and metabolic factors that ultimately culminate in joint failure. As the disease progresses, alterations in cartilage composition can cause erosion, leading to heightened susceptibility to mechanical disruption and the formation of cartilage wear particles. These particles contribute to the activation of synovial macrophages and synovial fibroblasts, which drive synovial fibrosis, joint stiffness, and chronic pain in OA patients. The presence of wear particles is also closely linked to increased roughness of the cartilage surface, resulting in elevated friction and further cartilage degradation.1Current management strategies for OA include lifestyle changes, small-molecule pain medication, large-molecule viscosupplementation, cell therapy, and surgical procedures. However, these treatments are insufficient in reversing the disease progression, and the development of disease-modifying OA drugs (DMOADs) has emerged as a promising strategy. The potential side effects associated with long-term systemic administration of DMOADs may undermine their therapeutic benefits, leading to an increased interest in intraarticular (IA) administration of lipid-based drug delivery systems (DDSs).2This approach reduces systemic exposure, minimises side effects, and increases local bioavailability. Combining cartilage lubrication with drug delivery has shown promise in treating OA, as DDSs can improve drug retention, provide on-demand drug release, and reduce cartilage wear and tear.3

[0003] Liposomes have shown promise in clinical settings for improving corticosteroid therapy in OA treatment.4However, they possess some limitations that need to be addressed. One of the main concerns is their small size, which may lead to their rapid removal from the joint space, thereby reducing their therapeutic efficacy.5The small particle size of below 300 nm has been associated with rapid clearance from the joint, necessitating frequent administration of the formulation and increasing the risk of inducing infection. This rapid clearance is partly due to phagocytosis by macrophages, which engulf and eliminate smaller particles more efficiently. In contrast, particles above 10 pm can avoid phagocytosis and beretained in both naive and inflamed joints for over six weeks.5’6Moreover, although small unilamellar liposomes exhibit excellent lubricating properties in vitro,7ex vivo studies on cartilage have revealed a lack of lubricating effect.89The superior lubrication by liposomes in vitro is linked to the hydration property of phospholipids that form a hydration shell, which is resistant to pressure and effectively reduces friction.7However, this discrepancy in ex vivo studies could be attributed to the penetration of liposomes into the porous cartilage structure, which results in poor retention on the surface necessary for providing an efficient lubrication.8

[0004] The development of calcium aggregated liposomes (ALs) that have the ability to sustain drug release by increasing the barrier for drug diffusion through layering multiple phospholipid membranes aggregated together, has recently been reported.10 11Irreversible aggregates of nearly 100 pm in diameter by using zinc as the aggregating agent,9which possesses anti-inflammatory activity,12have also been reported. The data showed a prolonged release of a potential DMAOD, rapamycin, beyond that of plain liposomes. These ALs were efficient in significantly reducing friction in vitro, and ex vivo they protected cartilage from increased friction caused by the aggregating agent. However, the study on human OA synovial fibroblasts (OASFs) demonstrated significant toxicity of the aggregating agent, limiting the system's ability to deliver the drug in a therapeutic dose.9

[0005] Thus, there remains a need for an improved alternative delivery system for OA management, which is non-toxic to human synovial cells and preferably also possesses antiinflammatory and / or anti-fibrotic activity.

[0006] Dendrimers are branched core-shell structures with a precisely defined number of focal points between the core and the shell, determining their generation (G1, G2, G3, etc.). As described herein, the inventors have surprisingly found that aggregates formed between polycationic aggregation agents and anionic lipid compositions (e.g. dendrimer-liposome complexes), are capable of significantly suppressing friction and improving particle retention on the cartilage surface. Thus, it has unexpectedly been found that the compositions of the invention can be used for intraarticular delivery of drugs for OA treatment.BRIEF SUMMARY OF THE DISCLOSURE

[0007] In accordance with the present invention, there is provided a composition for use in the treatment of a joint disease or disorder, wherein the composition comprises: an anionic lipid composition; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.

[0008] Suitably, the composition further comprises a pharmaceutically active agent. Thus, in embodiments, the composition comprises: an anionic lipid composition; a polycationic aggregation agent; and a pharmaceutically active agent, wherein the composition is administered intraarticularly. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition. It may be that the pharmaceutically active agent is incorporated into or constituted by the polycationic aggregation agent.

[0009] Also provided, is a composition comprising: an anionic liposome; and a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.

[0010] In embodiments, the composition further comprises a pharmaceutically active agent. Thus, in embodiments, the composition comprises: an anionic liposome; a polycationic aggregation agent; and a pharmaceutically active agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.

[0011] It may be that the pharmaceutically active agent is encapsulated in the anionic liposome.

[0012] Also provided, is a composition comprising: an anionic liposome; and a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86);(k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90);(KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70);(kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74);(kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or(rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82).

[0013] In embodiments, the composition comprises: an anionic liposome; and a cationic dendrimer aggregation agent,wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0014] Suitably, the composition further comprises a pharmaceutically active agent. Thus, in embodiments, the composition comprises: an anionic liposome; a cationic dendrimer aggregation agent; and a pharmaceutically active agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86);(k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90);(KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70);(kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74);(kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or(rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82).It may be that the composition comprises: an anionic liposome; a cationic dendrimer aggregation agent; and a pharmaceutically active agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). It may be that the pharmaceutically active agent is encapsulated in the anionic liposome.

[0015] In embodiments the composition is an aggregated composition comprising aggregates comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent). In embodiments, the anionic lipid composition and the polycationic aggregation agent form an aggregate beforeintraarticular administration to a subject. In embodiments where the anionic lipid composition is in the form of liposomes or particles (e.g. lipid nanoparticles) the aggregates comprise one molecule of the polycationic aggregation and a plurality (two or more) liposomes or lipid particles.

[0016] In those embodiments where the aggregated composition comprises a pharmaceutically active agent, the aggregated composition provides sustained release of the pharmaceutically active agent following intraarticular administration to the subject.

[0017] Also provided, is an aggregated composition of the invention, for use as a medicament.

[0018] Also provided, is an aggregated composition of the invention, for use in the treatment of a joint disease or disorder.

[0019] Also provided, is a method of treating a joint disease or disorder in a subject, the method comprising administering to the subject an effective amount of an aggregated composition of the invention. Suitably, the aggregated composition is intraarticularly administered to a joint of the subject.

[0020] Also provided is the use of an aggregated composition of the invention, for the manufacture of a medicament for the treatment of a joint disease or disorder in a subject.

[0021] Also provided, is an aggregated composition of the invention, for use in the treatment of a joint disease or disorder, wherein the composition is administered intraarticularly to a joint of a subject.

[0022] Also provided, is a kit comprising: a) a first container comprising an anionic lipid composition; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use as defined herein.

[0023] Suitably, the first container further comprises a pharmaceutically active agent. Thus, in embodiments, the kit comprises: a) a first container comprising an anionic lipid composition and a pharmaceutically active agent; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use as defined herein.

[0024] Further aspects and features of the invention are set out in the detailed description below.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 - Aggregation profile of DendriXALs (Dendril (Del) and Dendri4 (De4)) with changes of optical density at A = 450 nm and changes in zeta potential in dependence of the charge ratio (+ from DendriXs and - from DSPG molecules on liposomes). Each data point on the graph represents the measurement of one replicate, while the connecting line represents the mean value of each replicate. Each measurement was performed with 3 replicates, while the charge ratios at 500 and 1000 were performed with 1.

[0026] Figure 2 - Aggregation in presence of NaCI at different concentrations. The optical density was measured with a plate reader at 450 nm wavelength 5 minutes after mixing DendriXs and liposomes. Concentration of DendriXs was kept constant at 50 pg / mL and lipid content was adjusted (0.66 mM for Dendril , and 0.73 mM for Dendri4). NaCI was mixed with DendriXs before the mixing with liposomes.

[0027] Figure 3 - Expression of pro-fibrotic genes a) aSMA, b) Col1A1 , and c) Col3A1 on OASFs that were stimulated with 10 ng / mL TGFp and treated with DendriXs for 24 h. Oneway ANOVA and Tukey's multiple comparisons test were run. Statistical significance is designated as: *p<0.05, **p<0.01 , ***p<0.001 , ****p<0.0001.

[0028] Figure 4 - Toxicity of DendriXs and DendriXALs as measured with a CCK8 cell viability assay. The OASFs were in concentration of 5k cells per well in a 96-well plate. The cells were then treated with conditions of varying dendrimer concentrations for 48 h and the viabilities were normalised to the measured fluorescence signal of the condition treated with DM EM (100%).

[0029] Figure 5 - CryoTEM images of liposomes and DendriXALs. The total lipid concentration for all samples is 2 mM with adjusted DendriX concentration (152 pg / mL Dendril and 139 pg / mL Dendri4).

[0030] Figure 6 - Release of rapamycin from customised dialysis device with 10 % ethanol in ultrapure water as release medium. The total lipid concentration in all cases was 5 mM with a 30 / 1 L / D ratio. Results are reported as a mean of 3 replicates with standard deviations.

[0031] Figure 7 - Morphology of DendriXALs on a macro-level. Liposomes were labelled with DiD fluorescent probe, aggregated with DendriXs, and imaged with a fluorescence microscope using Tx red filter and brightfield. The total lipid concentration was 5 mM and DendriX concentration was adjusted (381 pg / mL Dendril and 347 pg / mL Dendri4).

[0032] Figure 8 - Lubrication of ex vivo porcine cartilage with liposomes, DendriXs and DendriXALs. For all samples, DendriX content was kept constant at 50 mg / mL while theliposomal concentration was adjusted for Dendri4ALs (0.73 mM) and DendrilALs (0.66 mM). A One-way ANOVA with Tukey's multiple comparisons test was run. Statistical significance is designated as: *P < 0.05 **P < 0.01 , ***P < 0.001 , ****p < 0.0001. The mean COF values are specified within the bars for each condition.

[0033] Figure 9 - Retention on cartilage surface. A) comparison of fluorescence intensities from the measured area of interest, which was kept constant among all samples. Each condition was tested in 3 replicates. For statistical analysis the two groups were compared with a t-test and statistical significance is designated as *p < 0.05. B) Representative images of DendrilALs, liposomes and buffer samples with 50X magnification. C) Representative images of Dendri4ALs, liposomes and buffer samples with 50X magnification. For all samples, DendriX content was kept constant at 50 mg / mL while the liposomal concentration was adjusted for Dendri4ALs (0.73 mM) and DendrilALs (0.66 mM).

[0034] Figure 10 - Uptake of DiD labelled Dendri4ALs by macrophages after 3 h incubation. A) DiD intensity normalised to the cell count and the positive liposome control to account for the variability in the independently prepared DiD labelled liposomes. B) A representative histogram of the DiD intensity within live macrophages for DM EM negative control, liposome positive control and Dendri4AL. C) Images of representative cells, acquired with Image Stream fluorescent imaging flow cytometer. For statistical analysis the two groups were compared with the unpaired t-test and statistical significance is designated as *p < 0.05.

[0035] Figures 11A and 11 B - Aggregation profiles of aggregated liposomes with different polycationic aggregation agents (as listed in Table 3) at standard concentrations of DPPC- DSPG liposomes (1 mM) and varying + / - charge ratios, with changes of turbidity (optical density) measured at A = 450 nm at t = 0 h and t = 1 h. Technical replicates are reported, n=4.

[0036] Figure 12 - Uptake of DPPC-DSPG liposomes and aggregated liposomes prepared with different polycationic aggregating agents (Dendril (D1), glatiramer acetate (GA), i- PAMAM, LL-37, Polymyxin B (PMB) and polyarginine (Poly-Arg)) by RAW264.7 cells. For statistical analysis, one way ANOVA and Dunnet multiple comparisons test was performed, and statistical significance is designated as *p<0.05, **p<0.01 , ****p<0.0001.

[0037] Figure 13 - Comparison of the viabilities of zinc aggregated liposomes (ZnAL) comprising rapamycin (RAPA-ZnAL) and polycationic aggregated liposomes (DendrilAL and Dendri4AL) comprising rapamycin (RAPA-Dendri1AL and RAPA-Dendri4AL, respectively) on OA synovial fibroblasts. The aggregated liposomes were compared to a liposome control without RAPA (Liposome Ctrl), and a RAPA control (RAPA Ctrl). *CCK-8 assay; **Live / Dead assay.

[0038] Figure 14 - Comparison of the cytotoxicity of zinc aggregated liposomes (Zn2+) and polycationic aggregated liposomes prepared with Dendril , Dendri4 and LL-37 (D1 , D4, and LL-37, respectively) on RAW264.7 macrophages. The aggregated liposomes were compared to a liposome control (free liposomes).DETAILED DESCRIPTION

[0039] Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0040] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0041] For the avoidance of doubt, the information disclosed earlier in this specification under the heading “Background” is relevant to the invention and is to be read as part of the disclosure of the invention.

[0042] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.Definitions

[0043] Unless otherwise stated, the following terms used in the specification and claims have the following meanings set out below.

[0044] Reference to “composition of the invention” refers to a composition comprising the anionic lipid composition, the polycationic aggregation agent and optionally a pharmaceutically active agent.

[0045] The term “treatment”, and the therapies encompassed by this invention, include the following and combinations thereof: (1) reducing the risk of or inhibiting, e.g. delaying, initiation and / or progression of, a state, disorder or condition; (2) preventing, e.g. reducing the risk of, or delaying the appearance of clinical symptoms of a state, disorder or condition developing in a patient (e.g. human or animal) that may be afflicted with or predisposed to the state, disorder or condition but does not yet experience or display clinical or subclinical symptoms of the state, disorder or condition; (3) inhibiting the state, disorder or condition (e.g., arresting, reducing or delaying the development of the disease, or a relapse thereof in case of maintenance treatment, of at least one clinical or subclinical symptom thereof); and / or (4) relieving the condition (e.g. causing regression of the state, disorder or condition or at least one of its clinical or subclinical symptoms). Where the composition of the invention is used in the treatment of a patient, treatment contemplates any one or more of: maintaining the health of the patient; restoring or improving the health of the patient; and delaying the progression of the disorder. The benefit to a patient to be treated may be either statistically significant or at least perceptible to the patient or to the physician. It will be understood that a medicament will not necessarily produce a clinical effect in every patient to whom it is administered, and this paragraph is to be understood accordingly. The compositions and methods described herein are of use for therapy and / or prophylaxis of disease. The compositions and methods described herein are of use for inhibiting or preventing disease progression.

[0046] The treatments may include maintenance therapy of patients who have suffered a disorder and whose condition has subsequently improved, e.g. because of treatment. Such patients may or may not suffer a symptomatic disorder. Maintenance therapy aims to arrest, reduce or delay (re-)occurrence or progression of a disorder.

[0047] Reference herein to a “therapeutically effective amount” is an amount sufficient to reduce or completely alleviate symptoms or other detrimental effects of a disorder; reverse, completely stop, or slow the progress of a disorder; or reduce the risk of a disorder getting worse; for example, an amount sufficient to induce remission of osteoarthritis, or an amount sufficient to maintain a remission of osteoarthritis. It is further within the skill of one of ordinary skill in the art to determine appropriate treatment duration, appropriate doses, and any potential combination treatments, based upon an evaluation of therapeutic or prophylactic response.

[0048] Reference to “sustained release” herein includes compositions which alter the release of a drug from the composition, particularly compositions which for example provide controlled release, extended release, modified release, or delayed release or any combination thereof, for example delayed and controlled release of a drug from a composition following administration, e.g. following intraarticular administration to a joint cavity of a subject.

[0049] The term “antibody”, in the context of the present invention, refers to “immunoglobulin” (Ig), which is defined as a protein belonging to the class IgG, IgM, IgE, IgA, or IgD (or any subclass thereof), and includes all conventionally known antibodies and functional fragments thereof. In the context of the present invention, a “functional fragment” of an antibody / immunoglobulin is defined as antigen-binding fragment or other derivative of a parental antibody that essentially maintains the properties of such a parental antibody. An “antigen-binding fragment” of an antibody / immunoglobulin is defined as a fragment (e.g., a variable region of an IgG) that retains the antigen-binding region. An “antigen-binding region” of an antibody typically is found in one or more hypervariable region(s) of an antibody, i.e., the CDR-1 , -2, and / or -3 regions. “Antigen-binding fragments” according to the invention include the domain of a F(ab')2 fragment and a Fab fragment. “Functional fragments” of the invention include Fab fragment, F(ab')2 fragment, Fab' fragment, scFv, dsFv, VHH, diabody, triabody, tetrabody, Fc fusion protein and minibody. The F(ab')2 or Fab domain may be engineered to minimise or completely remove the intermolecular disulphide interactions that occur between the CH1 and CL domains. The antibodies or functional fragments used for the present invention may be part of bi- or multifunctional constructs.

[0050] The term “dendrimer” refers to a polymer compound having a structure that is regularly branched from the centre. Thus, a dendrimer is composed of a central core, and a side-chain portion called a dendron. The term “generation” indicates the number of branches of dendron portion, e.g. G1 , G2, G3, etc. Thus, a G3 dendrimer (i.e. a generation 3 dendrimer) means that the dendron has been branched four times.

[0051] In certain embodiments the compositions of the present invention comprise dendrimers as the polycationic aggregation agent. Thus, in these embodiments the compositions of the present invention are also referred to as “dendrimer-aggregated liposomes” or “DendriXALs”. The dendrimers used in the compositions of the present invention are also referred to as “DendriXs”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4), and may also be referred to as “Dendril”, “Del” or “D1”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8), and may also bereferred to as “Dendri4”, “De4”, or “D4”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (k{NLE}y)s(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86), and may also be referred to as “SOY041”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (k{N LE}y)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90), and may also be referred to as “SOY031”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (KL)S(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70), and may also be referred to as “G3KL”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (kl)s(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74), and may also be referred to as “DMH13”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (kl)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78), and may also be referred to as “DMH18”. The polycationic aggregation agent (or cationic dendrimer aggregation agent) may comprise the following linear notation: (rl)s(krl)4(krl)2kk(Cis) (consisting of SEQ ID NO: 79 to 82) and may also be referred to as “Z34”.

[0052] In some embodiments the compositions of the present invention are substantially free from organic solvents. Thus, in some embodiments the compositions disclosed herein contain less than 10%, less than 5%, less than 1%, or suitably less than 0.01 %, or preferably less than 0.001 % of organic solvents. Preferably the compositions of the invention contain no detectable organic solvents.

[0053] The term “amino sugar” refers to a sugar molecule in which a hydroxyl group has been replaced with an amine group.

[0054] The term “anionic lipid composition” is a composition comprising lipids, for example, a composition comprising liposomes, lipid nanoparticles, solid lipid nanoparticles, and / or nanostructured lipid carriers, which have a negative surface charge.

[0055] The term “negative surface charge” or “negative surface potential” refers to the surface potential of the anionic lipid composition (e.g. the anionic liposome) at a pH in the range of between 6.0 and 8.0, preferably at pH 7.4. The surface potential (z-potential) is measured by the electrophoresis method. Such methods are well known to those skilled in the art. See, for example, ‘Dynamic Light Scattering (DLS) and Zeta Potential’ in the Examples section below.

[0056] The term “liposome” refers to a spherical-shaped vesicle, having at least one lipid bilayer. Examples of liposomes encompassed by the present invention include, but are not limited to, unilamellar vesicles (with one lipid bilayer, e.g. small unilamellar vehicles, or largeunilamellar vehicles), multilamellar vesicles (with more than one lamellar phase lipid bilayers), and multivesicular vesicles (wherein one vesicle contains one or more smaller vesicles).

[0057] The term “lipid nanoparticle” refers to a nanoparticle composed of lipids, which does not comprise a solid lipid core. In contrast, the term “solid lipid nanoparticle” (SLN) refers to a nanoparticle composed of lipids, which comprises a solid lipid core matrix.

[0058] The term “nanostructured lipid carrier” (NLC) refers to a nanoparticle composed of lipids, which comprises a mixture of both solid and liquid-crystalline lipids as a core matrix. As is well-known in the art, the term NLC encompasses three types of morphological models: i) NLC type I (imperfect crystal model); ii) NLC type II (multiple type); and iii) NLC type III (amorphous model) (as described in Adv Pharm Bull. 2020; 10(2): 150-165, which is incorporated herein by reference).

[0059] The term “polyamine” refers to an organic compound comprising two or more amino groups.

[0060] The term “peptide” refers to a short chain of amino acids (typically 2 to 50) linked by peptide bonds. A longer chain (typically 51 or more) of amino acids is referred to as a “polypeptide”.

[0061] The term “amino acid” refers to a molecule containing both an amino group and a carboxyl group. Suitable amino acids include, without limitation, both the D- and L-isomers of the naturally-occurring amino acids, as well as non-naturally occurring amino acids prepared by organic synthesis or other metabolic routes. The term amino acid, as used herein, includes without limitation, a-amino acids, p-amino acids, proteinogenic amino acids, non- proteinogenic amino acids, and amino acid analogs.

[0062] As the skilled person will be aware, a D-isomer of an amino acid can be denoted by a lower case letter. For example, the dendrimer DMH18 comprising the following linear notation: (kl)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78), comprises D-isomers of the amino acids listed. An L-isomer of an amino acid can be denoted by an upper case letter. For example, the dendrimer G3KL comprising the following linear notation: (KL)s(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70), comprises L-isomers of the amino acids listed. The dendrimer SOY031 comprising the linear notation: (k{N LE}y)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90) comprises a mixture of both L- and D-isomers of the amino acids listed. However, it will be understood that where a dendrimer is represented by a linear notation herein, the dendrimer could comprise either the D- and / or the L-isomers of the amino acids listed. For example, the dendrimer DMH18 comprising the following linear notation: (kl)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78), can also encompass a dendrimer withall L-isomers of the amino acids listed, or a mixture of both L- and D-isomers of the amino acids listed.

[0063] The term “a-amino acid” refers to a molecule containing both an amino group and a carboxyl group bound to a carbon which is designated the a-carbon.

[0064] The term “P-amino acid” refers to a molecule containing both an amino group and a carboxyl group in a configuration.

[0065] The term “proteinogenic amino acid” refers to any one of the 20 amino acids commonly found in peptides synthesized in nature, and known by the one letter abbreviations A, R, N, C, D, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y and V, as well as seleocysteine and pyrrolysine.

[0066] Non-limiting examples of amino acid analogs include homoserine, norleucine, methionine sulfoxide, and methionine methyl sulfonium.

[0067] Amino acids may be referred to herein by either their name, their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission.

[0068] The term “non-proteinogenic amino acid” refers to an amino acid which is not one of the 22 proteinogenic amino acids which are naturally encoded in the genome of organisms. Non-proteinogenic amino acids include, without limitation, hydroxyproline (Hyp), beta-alanine, citrulline (Cit), ornithine (Orn), norleucine (Nle, also referred to herein as {NLE}), 3- nitrotyrosine, nitroarginine, pyroglutamic acid (Pyr), p-alanine, y-Aminobutyric acid (GABA), 6- aminolevulinic acid, cystathionine, lanthionine, djenkolic acid and diaminopimelic acid.

[0069] The term “polyquaternium” or “polyquat” is the International Nomenclature for Cosmetic Ingredients designation for several polycationic polymers that are used, for example, in the personal care industry. Polyquaternium is a neologism used to emphasise the presence of quaternary ammonium centres in the polymer. Different polymers are distinguished by the numerical value that follows the word "polyquaternium". For example, polyquaternium-5, polyquaternium-7, and polyquaternium-47.

[0070] The term “polycationic aggregation agent” refers to an agent having two or more separate positively charged sites at a pH in the range of between 6.0 and 8.0, preferably at pH 7.4, and is capable of complexing, through non-covalent interactions (preferably electrostatic interactions), with one or more molecules of opposite charge (i.e. the anionic lipid composition).

[0071] The term “aggregated composition” is a composition comprising aggregates of polycationic aggregation agents complexed to the anionic lipid composition (e.g. an anioniclipid composition in the form of anionic liposomes, anionic lipid nanoparticles or anionic solid lipid nanoparticles). For example, in some embodiments an aggregated composition is a composition comprising a dendrimer-liposome complex, wherein the polycationic dendrimer has complexed one of more anionic liposomes (preferably a plurality of anionic liposomes). Aggregation between the anionic lipid composition with negative surface potential and the polycationic aggregation agent is caused by non-covalent interactions, including electrostatic interactions, hydrogen bonds, Van-der Waals, or a combination thereof. Aggregation between the polycationic aggregation agents and anionic lipid composition as described herein, can be monitored by analytical techniques well known in the art. For example, aggregation can be observed by measuring changes in optical density (turbidity) and / or zeta potential , as described in the Examples section herein.

[0072] An “intraarticular” composition is a composition that is injected into a joint (e.g. the joint cavity) of the subject. Thus, the composition of the claimed invention is administered to the subject intraarticularly, for the treatment of a joint disease or disorder.

[0073] Ingredients and excipients of the described compositions are suitable for the intended purpose. For example, pharmaceutical compositions comprise pharmaceutically acceptable ingredients.

[0074] If not otherwise stated, ingredients, components, excipients etc. of the compositions of the invention are suitable for one or more of the intended purposes discussed elsewhere herein.

[0075] Reference to “about” in the context of a numerical is intended to encompass the value + / - 10%. For example, about 20% includes the range of from 18% to 22%.Composition

[0076] Provided herein is a composition for use in the treatment of a joint disease or disorder, wherein the composition comprises: an anionic lipid composition; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.

[0077] In embodiments, the composition for use further comprises a pharmaceutically active agent. Thus, it may be that the composition for use comprises: an anionic lipid composition; a polycationic aggregation agent; anda pharmaceutically active agent, wherein the composition is administered intraarticularly.

[0078] In embodiments, the pharmaceutically active agent is incorporated into the anionic lipid composition. For example, it may be that the anionic lipid composition is a liposome composition, and the pharmaceutically active agent is encapsulated in the liposomes. It may be that the pharmaceutically active agent is a hydrophilic pharmaceutically active agent, and is encapsulated in the aqueous core of the liposome during lipid bilayer formation. It may be that the pharmaceutically active agent is a hydrophobic pharmaceutically active agent, and accumulates in the hydrophobic lipid bilayer of the liposome. Also contemplated is the encapsulation of a poorly water-soluble pharmaceutically active agent in the aqueous core of the liposome. Encapsulation of such poorly water-soluble active agents may be achieved using, for example, solvent-assisted loading methods wherein small amounts of water- miscible solvents are utilised to enhance solubility during liposome loading (see e.g. Wei-Lun Tang.et al, Systemic study of solvent-assisted active loading of gambogic acid into liposomes and its formulation optimization for improved delivery); Biomaterials, Vol 166, 2018,13-26, Thus, it may be that the composition for use comprises: an anionic lipid composition, wherein the anionic lipid composition comprises a pharmaceutically active agent; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.

[0079] In embodiments, the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug molar ratio of from about 100: 1 , 90: 1 , 80: 1 , 70: 1 , 60: 1 , 50: 1 , 40: 1 , 30: 1 , 20: 1 , 10: 1 , 5: 1 , 2.5: 1 , 1 :1 , 1 :2, 1 :3, 1 :5 or 1 : 10. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug molar ratio of from about 50:1 to about 1 :10, for example a lipid to drug ratio of about 40:1 to about 5:1 , or from about 60:1 to about 20:1 , about 35:1 to about 25:1. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug molar ratio of from about 50:1 , 45:1 , 40:1 , 35:1 , 30:1 , 25:1 , 20:1 , 15:1 , or 10:1. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to- drug molar ratio of from about 35: 1 , 34: 1 , 33: 1 , 32: 1 , 31 : 1 , 30: 1 , 29: 1 , 28: 1 , 27: 1 , 26: 1 or 25: 1. Preferably, it may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug molar ratio of about 30:1.

[0080] In other embodiments, the composition for use does not comprise a pharmaceutically active agent.

[0081] In embodiments, the anionic lipid composition and the polycationic aggregation agent form an aggregate. Thus, in embodiments, the composition for use as described herein is an aggregated composition comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent.

[0082] In embodiments, the mean size of the aggregates in the composition is in the range of from about 0.3 pm to 500 pm. It may be that the size of the aggregates in the composition is in the range of from about 0.5 pm to 500 pm It may be that the size of the aggregates in the composition is in the range of from about 0.3 pm to 300 pm, for example about 1 pm to about pm to 300 pm. It may be that the size of the aggregates in the composition is in the range of from about 1 pm to 200 pm. It may be that the mean size of the aggregates in the composition is in the range of from 10 pm to 100 pm. For example, it may be that the mean size of the aggregates in the composition is from about 10 pm, 20 pm, 30 pm, 40 pm, 50 pm, 60 pm, 70 pm, 80 pm, 90 pm, or 100 pm. The mean size of the aggregates in the composition can be determined by analytical methods well-known in the art. Suitably, the mean aggregation size of the aggregates in the composition can be measured using well-known methods, for example dynamic light scattering (DLS) (suitable for aggregates up to about 1 pm), particle size analyser (PSA) based on laser diffraction technology, cryogenic electron microscopy or optical microscopy (e.g. fluorescence microscopy using a suitable dye to stain the lipids). Suitable methods for determining and characterising lipid aggregates are described in G. Bordon et al.9

[0083] In embodiments, the composition for use is administered to the subject intraarticularly. Accordingly, the composition (e.g. the aggregated composition) for use is an injectable composition, which is administered intraarticularly to a joint (e.g. the joint cavity) in a subject in need thereof.

[0084] In embodiments, the composition for use comprises a pharmaceutically active agent which is not incorporated in the anionic lipid composition. Thus, it may be that the anionic lipid composition forms an aggregate with the polycationic aggregation agent and the pharmaceutically active agent.

[0085] In embodiments, the polycationic aggregation agent is a pharmaceutically active agent as described herein (for example, an anti-inflammatory agent, an anti-microbial agent, or an anti-fibrotic agent). Thus, it may be that the anionic lipid composition forms an aggregate with the pharmaceutically active agent.

[0086] In embodiments, the amount of polycationic aggregation agent in the composition is the amount required to achieve the desired rate of release of the pharmaceutically active agent.

[0087] The molar ratio of anionic lipid composition to the polycationic aggregation agent in the composition can vary depending upon, the nature of the polycationic aggregation agent. Generally the anionic lipid composition is present in a molar excess relative to the polycationic aggregation agent. The molar excess of anionic lipid composition to polycationic increases as the number of cationic groups in the polycationic aggregation agent increases. In embodiments, the molar ratio of the anionic lipid composition to the polycationic aggregation agent in the composition is from 2:1 to 2000:1 , for example from 10:1 to 1500:1 , from 10:1 to 1200:1 , from 10:1 200:1 , from 100:1 to 1500:1 or 150:1 to 1200:1. It may be that the molar ratio of the anionic lipid composition to the polycationic aggregation agent in the composition is from 20:1 to 180:1. It may be that the molar ratio of the anionic lipid composition to the polycationic aggregation agent in the composition is from 25:1 to 160:1.

[0088] In embodiments, the anionic lipid composition and the polycationic aggregation agent form an aggregate before intraarticular administration to the subject. It may be that the aggregated composition is prepared shortly before the composition is administered to a subject. For example, the aggregated composition may be prepared by mixing the anionic lipid composition and the polycationic aggregation agent to form aggregates comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent. Thus, it may be that an aggregated composition as described herein is administered to the subject intraarticularly.

[0089] In other embodiments, the anionic lipid composition and the polycationic aggregation agent form an aggregate in situ, following intraarticular administration to the subject. Thus, it may be that a composition as described herein is administered to the subject intraarticularly, and the composition forms an aggregated composition in situ.

[0090] In embodiments, the composition as described herein forms a sustained release depot in situ following intraarticular administration to the subject. In certain embodiments an aggregated composition as described herein forms a sustained release depot following intraarticular administration to the subject from which the pharmaceutically active agent is released.

[0091] In certain embodiments the composition has a pH in the range of about 6.0 to about 8.0. Suitably the composition has a pH of from about 7.0 to about 8.0, preferably a pH of about 7.1 to about 7.7, more preferably the composition has a pH of about 7.4. Optionally the composition may comprise a buffer to maintain the pH within the desired range.

[0092] As illustrated in the Examples, the ionic strength of the composition can affect the degree of aggregation between the polycationic aggregation agent and the anionic lipid. Accordingly in embodiments any of the compositions described herein may further comprisea salt, for example sodium chloride. It may be that the salt (e.g. sodium chloride) is present in the composition at a concentration of from greater than about 0.1 mM to less than about 300 mM. It may be that the salt (e.g. sodium chloride) is present in the composition at a concentration of from about 1 mM to about 250 mM. It may be that the salt (e.g. sodium chloride) is present in the composition at a concentration of from about 10 mM to about 200 mM. Preferably, it may be that the salt (e.g. sodium chloride) is present in the composition at a concentration of less than about 150 mM . Thus, it may be that the sodium chloride is present in a concentration of from about 100 mM to about 150 mM. For example, the composition may comprise sodium chloride in a concentration of from about 135 mM to about 145 mM.

[0093] In other embodiments, it may be that the compositions described herein do not further comprise a salt. It may be that the compositions described herein do not further comprise sodium chloride.

[0094] In embodiments, it may be that a positive / charge ratio of greater than about 0.5 is required to initiate aggregation between the anionic liposomes described herein and the polycationic aggregating agents described herein. Thus, it may be that the positive charge ratio is greater than about 1 , for example, from about 1 to about 100. It may be that the positive charge ratio is from about 5 to about 50, for example, about 10. The positive / charge ratio may be assessed as described in the Examples herein (see, for example, Examples 2 and 7).Compositions comprising polycationic aggregation agents (e.g. cationic dendrimer aggregation agents)

[0095] Also provided herein, the composition is a composition comprising: an anionic lipid composition; and a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.

[0096] It may be that the polycationic aggregating agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i- PAM AM), LL-37, and polyarginine.Thus, it may be that the polycationic aggregating agent is a cationic dendrimer aggregation agent with the linear notation: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) (i.e. Dendril). It may be that the polycationic aggregating agent is a cationic dendrimer aggregation agent with the linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8) (i.e. Dendri4). It may be that the polycationic aggregating agent is i-PAMAM. It may be that the polycationic aggregating agent is LL-37. It may be that the polycationic aggregating agent is polyarginine.

[0097] Also provided herein the composition is a composition comprising an anionic lipid composition, and a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). It may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0098] In some embodiments the anionic lipid composition comprises anionic liposomes. In some embodiments the anionic lipid composition comprises anionic lipid nanoparticles. In some embodiments the anionic lipid composition comprises solid lipid nanoparticles.

[0099] In embodiments, the composition further comprises a pharmaceutically active agent. Accordingly, in some embodiments, the composition comprises an anionic lipid composition; a polycationic aggregation agent; and a pharmaceutically active agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.In other embodiments, the composition comprises an anionic lipid composition, a cationic dendrimer aggregation agent, and a pharmaceutically active agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). It may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0100] In some embodiments, the anionic lipid composition comprises anionic liposomes. Thus, also provided herein, is a composition comprising: an anionic liposome; and a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain),tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.

[0101] In certain embodiments, the composition comprises: an anionic liposome; a polycationic aggregation agent; and a pharmaceutically active agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.

[0102] Also provided herein is a composition comprising:• an anionic liposome; and• a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). It may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0103] In certain embodiments, the composition comprises: an anionic liposome; a cationic dendrimer aggregation agent; anda pharmaceutically active agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). It may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0104] In embodiments, the anionic liposome comprises a pharmaceutically active agent. For example, it may be that the pharmaceutically active agent is encapsulated in the anionic liposome. It may be that the pharmaceutically active agent is a hydrophilic pharmaceutically active agent, and is encapsulated in the aqueous core of the anionic liposome during lipid bilayer formation. It may be that the pharmaceutically active agent is a hydrophobic pharmaceutically active agent, and accumulates in the hydrophobic lipid bilayer of the anionic liposome. It may be that the pharmaceutically active agent is a poorly water-soluble active agent encapsulated in the aqueous core of the liposome (e.g. using solvent assisted liposome loading described in Wei-Lun Tang, et al, supra) Thus, in embodiments, the composition comprises: an anionic liposome, wherein the anionic liposome comprises a pharmaceutically active agent; and a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.In other embodiments, the composition comprises: an anionic liposome, wherein the anionic liposome comprises a pharmaceutically active agent; and a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). It may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0105] In embodiments, the pharmaceutically active agent is incorporated into the anionic liposome at a lipid-to-drug molar ratio of from about 100: 1 , 90: 1 , 80: 1 , 70: 1 , 60: 1 , 50: 1 , 40: 1 , 30:1 , 20:1 , 10:1 , 5:1 , 2.5:1 , 1 :1 , 1 :2, 1 :3, 1 :5 or 1 :10. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug molar ratio of from about 50:1 to about 1 :10, for example a lipid to drug molar ratio of about 40:1 to about 5:1 , or from about 60:1 to about 20:1 , about 35:1 to about 25:1. It may be that the pharmaceutically active agent is incorporated into the anionic liposome at a lipid-to-drug molar ratio of from about 50: 1 , 45: 1 , 40: 1 , 35: 1 , 30: 1 , 25:1 , 20:1 , 15:1 , or 10:1. It may be that the pharmaceutically active agent is incorporated into the anionic liposome at a lipid-to-drug molar ratio of from about 35: 1 , 34: 1 , 33: 1 , 32: 1 , 31 : 1 , 30: 1 , 29: 1 , 28: 1 , 27: 1 , 26: 1 or 25: 1. Preferably, it may be that the pharmaceutically active agent is incorporated into the anionic liposome at a lipid-to-drug molar ratio of from about 30:1.

[0106] In other embodiments, the composition does not comprise a pharmaceutically active agent.

[0107] In embodiments, the polycationic aggregation agent is a cationic dendrimer aggregation agent. In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (k{NLE}y)8(kkl)4(kll)2kllll(consisting of SEQ ID NO: 87 to 90). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (KL)s(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (kl)s(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (kl)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78). In embodiments, the cationic dendrimer aggregation agent comprises the linear notation: (rl)s(krl)4(krl)2kk(Cis) (consisting of SEQ ID NO: 79 to 82). Preferably, it may be that the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) (i.e. Dendril); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8) (i.e. Dendri4).

[0108] In embodiments, the polycationic aggregation agent is selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straightchain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3. Preferably, it may be that the polycationic aggregation agent is selected from the group consisting of: i-PAMAM, LL-37, and polyarginine. Thus, it may be that the polycationic aggregation agent is i-PAMAM. It may be that the polycationic aggregation agent is LL-37. It may be that the polycationic aggregation agent is polyarginine.

[0109] In embodiments, the polycationic aggregation agent comprises one or more polycationic aggregation agents described herein (e.g. one or more cationic dendrimer aggregation agents).

[0110] The anionic liposome comprises negatively charged lipids. In certain embodiments the anionic liposome further comprises one or more neutral or zwitterionic lipid. It may be that the anionic liposome further comprises zwitterionic lipids. Thus, it may be that the anionic liposome comprises negatively charged lipids and zwitterionic lipids. In embodiments, the anionic liposome further comprises cholesterol. Thus, it may be that the anionic liposome comprises negatively charged lipids and cholesterol. It may be that the anionic liposome comprises negatively charged lipids, zwitterionic lipids and cholesterol. In embodiments, the anionic liposome comprises about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% mol / mol of negatively charged lipids relative to the remaining liposome lipids. For example, it may be that the anionic liposome comprises about 15%, 16%, 17%, 18%, 19%, 20%, 21 %, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% mol / mol of negatively charged lipids relative to the remaining liposome lipids. In preferred embodiments, it may be that the anionic liposome comprises about 25% mol / mol of negatively charged lipids relative to the remaining liposome lipids. It may be that the anionic liposome comprises about 25% mol / mol ofnegatively charged lipids relative to the remaining liposome lipids, wherein the remaining liposome lipids include zwitterionic lipids and / or cholesterol.

[0111] In embodiments, the anionic liposome comprises negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn-g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn- glycero-3- phosphate (DOPA), 1 ,2-distearoyl-sn-g / ycero-3-phospho-(T -rac-glycerol) (DSPG),1.2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1- rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1-rac-glycerol) (DOPG), 1 ,2- dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '- myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'- triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DOPI-P3), or combinations thereof.

[0112] In embodiments, the anionic liposome further comprises cholesterol, or a phosphocholine lipid, or combinations thereof. In embodiments, the anionic liposome further comprises cholesterol, or phosphocholine lipids such as 1 ,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC), and 1 ,2-distearoyl-sn-glycero-3-phosphocholine (DSPG), or combinations thereof. In embodiments, the anionic liposome further comprises cholesterol,1.2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1 ,2-distearoyl-sn-glycero-3- phosphocholine (DSPC), phosphatidylcholine (PC), 1 ,2-Dioleoyl-sn-glycero-3- phosphocholine (DOPC), or combinations thereof. In embodiments, the anionic liposome further comprises cholesterol, 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), or 1 ,2- distearoyl-sn-glycero-3-phosphocholine (DSPC), or combinations thereof.

[0113] Thus, it may be that the anionic liposome comprises DPPC. It may be that the anionic liposome comprises DSPG. It may be that the anionic liposome comprises cholesterol. It may be that the anionic liposome comprises DSPG and DPPC. It may be that the anionic liposome comprises DSPG and cholesterol. It may be that the anionic liposome comprises DSPG, DPPC and cholesterol.

[0114] In embodiments, the composition is an injectable composition. Thus, it may be that the composition is a subcutaneous, an intraarticular, an intramuscular, or an intradermal injectable composition. In embodiments, the composition is administered to the subject subcutaneously, intraarticularly, intramuscularly or intradermally. Preferably, the aggregated composition is an intraarticular injectable composition, and thus the aggregated composition is administered to the subject intraarticularly.

[0115] In embodiments, the anionic lipid composition (e.g. anionic liposome) and the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) form an aggregate.Accordingly, in embodiments, the composition is an aggregated composition comprising aggregates comprising the polycationic aggregation agent and the anionic lipid composition (e.g. anionic liposome). In preferred embodiments, the composition is an aggregated composition comprising aggregates comprising the cationic dendrimer aggregation agent and the anionic lipid composition (e.g. anionic liposome). In some embodiments the aggregates comprise the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) and one or more anionic liposomes, preferably a plurality of anionic liposomes. In embodiments, the mean size of the aggregates in the aggregated composition is in the range of from about 0.3 pm to 500 pm. In embodiments, the mean size of the aggregates in the aggregated composition is in the range of from about 0.5 pm to 500 pm. It may be that the mean size of the aggregates in the composition is in the range of from about 1 pm to 200 pm It may be that the mean size of the aggregates in the composition is in the range of from about 1 pm to 200 pm. It may be that the mean size of the aggregates in the composition is in the range of from 10 pm to 100 pm. For example, it may be that the mean size of the aggregates in the composition is from about 10 pm, 20 pm, 30 pm, 40 pm, 50 pm, 60 pm, 70 pm, 80 pm, 90 pm, or 100 pm. The mean size of the aggregates in the composition can be determined by analytical methods well-known in the art. Suitably, the mean size of the aggregates in the composition can be measured using well-known methods as described above in relation to the composition.

[0116] In embodiments, the aggregated composition comprises a pharmaceutically active agent which is not encapsulated in the anionic liposome. Thus, it may be that the anionic liposome forms an aggregate with the polycationic aggregation agent and the pharmaceutically active agent. It may be that the anionic liposome forms an aggregate with the cationic dendrimer aggregation agent and the pharmaceutically active agent.

[0117] In embodiments, the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) is present in the composition in an amount sufficient to form aggregates with the anionic lipid composition (e.g. anionic liposome). Thus, it may be that the cationic dendrimer aggregation agent is present in the composition in an amount sufficient to form aggregates with the anionic lipid composition (e.g. anionic liposome). The amount of polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) may also be used to modulate the rate of release of the pharmaceutically active agent from the composition following administration to a subject.

[0118] The molar ratio of the anionic liposome to the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) in the composition may vary depending on the number of cationic groups present in the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent). In certain embodiments, the molar ratio of the anionic liposome to thepolycationic aggregation agent (e.g. cationic dendrimer aggregation agent) in the composition 2:1 to 2000:1 , for example from 10:1 to 1500:1 , from 10:1 to 200:1 , from 100:1 to 1500:1 or 150:1 to 1200:1 It may be that the molar ratio of the anionic liposome to the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) in the composition is from 20:1 to 180: 1. It may be that the molar ratio of the anionic liposome to the polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) in the composition is from 25:1 to 160:1.

[0119] In preferred embodiments, the anionic lipid composition (e.g. anionic liposome) and polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) form an aggregate before administration to the subject. In embodiments, the aggregated composition is administered to the subject subcutaneously, intraarticularly, intramuscularly or intradermally. Thus, it may be that the anionic liposome and polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) form an aggregate before intraarticular administration to the subject.

[0120] In other embodiments, the anionic liposome and polycationic aggregation agent (e.g. cationic dendrimer aggregation agent) form an aggregate in situ, following administration to the subject. In embodiments, the aggregated composition is administered to the subject subcutaneously, intraarticularly, intramuscularly or intradermally. In preferred embodiments the composition is administered to the subject intraarticularly.

[0121] In embodiments, the aggregated compositions described herein which comprise a pharmaceutically active agent provide sustained release of the pharmaceutically agent following intraarticular administration of the composition to the subject. In some embodiments the aggregated composition forms a sustained release depot following intraarticular administration from which the pharmaceutically active agent is released.

[0122] In embodiments, the aggregated composition of the invention is for use in the treatment of a joint disease or disorder, as described herein.Anionic Lipid Composition

[0123] In embodiments, the anionic lipid composition comprises liposomes, lipid nanoparticles, solid lipid nanoparticles or nanostructured lipid carriers, or combinations thereof. In embodiments, the anionic lipid composition comprises liposomes. In embodiments, the anionic lipid composition comprises lipid nanoparticles. In embodiments, the anionic lipid composition comprises solid lipid nanoparticles. In embodiments, the anionic lipid composition comprises nanostructured lipid carriers. In preferred embodiments, the anionic lipid composition comprises liposomes. Accordingly, it may be that the anionic lipid composition is an anionic liposome composition. In some embodiments the anionic lipid composition is an anionic unilamellar liposome composition. In some embodiments theanionic lipid composition is an anionic multilamellar liposome composition. In some embodiments the anionic lipid composition is an anionic multivesicular liposome composition.

[0124] Liposomes have several advantages due to their high biocompatibility (as they consist of phospholipid / cholesterol bilayers and aqueous phase) and their ability to carry both hydrophilic and lipophilic drugs. Water-soluble drugs can be incorporated into the aqueous phase of liposomes, while fat-soluble drugs can be incorporated into their lipid phase. Waterinsoluble drugs may also be incorporated into the aqueous core of a liposome by using solvents during liposome loading as described above. The preparation of liposomes is well- known to those skilled in the art, for example, the thin-film hydration technique, as described in the Examples section herein. It will be understood that other liposome preparation methods are also encompassed by the claimed invention, such as those described in Pharmaceutics. 2022 Mar; 14(3): 543, which is incorporated herein by reference.

[0125] The liposomes comprise negatively charged lipids (lipids bearing a negatively charged head, also described herein as “anionic liposomes”). As the hydrophilic lipid head is located on the outer surface of the liposomes, the incorporation of these lipids into the structure of their liposomes gives a negative surface potential.

[0126] In certain embodiments the anionic lipid composition comprises anionic liposomes with a mean hydrodynamic diameter of less than about 200 nm. A liposome size of less than 200 nm advantageously enables the composition sterilised by sterile filtration. In certain embodiments the anionic lipid composition comprises anionic liposomes with a mean hydrodynamic diameter of from about 100 nm to about 200 nm. For example wherein the anionic liposomes have a mean hydrodynamic diameter of from about 120 nm to about 180 nm, about 130 nm to about 170 nm or about 140 nm to about 150 nm. In some embodiments the anionic liposomes have a mean hydrodynamic diameter of about 145 nm.

[0127] In certain embodiments the anionic lipid composition comprises anionic liposomes with a polydispersity index which is below 0.5, preferably below 0.2. For example a polydispersity index of from about 0.05 to about 0.2. Thus it may be that the anionic lipid composition comprises anionic liposomes with a polydispersity index of from about 0.05 to about 0.15.

[0128] The hydrodynamic diameter and polydispersity index may be determined using dynamic light scattering, for example using a Litesizer 500 instrument (Anton Paar®, Austria) with a backscatter angle of 175° and a 658 nm laser at 25 °C.

[0129] In certain embodiments the anionic lipid composition comprises anionic liposomes with a zeta potential of from about - 20 mV to -100 mV. For example the anionic liposomes may have a zeta potential of from -30 mV to -65 mV, or from about -55 mV to -60 mV. Thezeta potential may be determined using conventional techniques, for example by using electrophoretic light scattering (ELS). For example using a Litesizer 500 instrument (Anton Paar®, Austria) with a backscatter angle of 175° and a 658 nm laser at 25 °C together with an Omega cuvette (Anton Paar®, Austria) with laser Doppler microelectrophoresis.

[0130] In embodiments, the anionic lipid composition comprises a pharmaceutically active agent. In embodiments, the anionic lipid composition is a liposome composition, and the liposome composition comprises a pharmaceutically active agent. For example, it may be that the pharmaceutically active agent is encapsulated in the liposomes. It may be that the pharmaceutically active agent is a hydrophilic pharmaceutically active agent, and is encapsulated in the aqueous core of the liposome during lipid bilayer formation. It may be that the pharmaceutically active agent is a hydrophobic pharmaceutically active agent, and accumulates in the hydrophobic lipid bilayer of the liposome.

[0131] In embodiments, the pharmaceutically active agent is incorporated into the anionic lipid composition (e.g. the liposome composition) at a lipid-to-drug ratio of from about 100:1 , 90:1 , 80:1 , 70:1 , 60:1 , 50:1 , 40:1 , 30:1 , 20:1 , 10:1 , 5:1 , 2.5:1 , 1 :1 , 1 :2, 1 :3, 1 :5 or 1 :10. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition at a lipid-to-drug ratio of from about 50:1 to about 1 :10, for example a lipid to drug ratio of about 40: 1 to about 5:1 , or from about 60: 1 to about 20: 1 , about 35: 1 to about 25: 1. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition (e.g. the liposome composition) at a lipid-to-drug ratio of from about 50:1 , 45:1 , 40:1 , 35:1 , 30:1 , 25:1 , 20:1 , 15:1 , or 10:1. It may be that the pharmaceutically active agent is incorporated into the anionic lipid composition (e.g. the liposome composition) at a lipid-to-drug ratio of from about 35: 1 , 34: 1 , 33: 1 , 32: 1 , 31 : 1 , 30: 1 , 29: 1 , 28: 1 , 27: 1 , 26: 1 or 25: 1. Preferably, it may be that the pharmaceutically active agent is incorporated into the anionic lipid composition (e.g. the liposome composition) at a lipid-to-drug ratio of about 30:1.

[0132] Suitably the pharmaceutically active agent is incorporated into the anionic lipid composition (e.g. the liposome composition) with a high encapsulation efficiency. The encapsulation efficiency (EE %) may be determined according to the following equation:EE% = amount of pharmaceutically active agent encapsulated x 100% total amount of pharmaceutically active agent

[0133] In certain embodiments the pharmaceutically active agent is encapsulated with an encapsulation efficiency (EE %) of at least 20 %. For example the EE% is at least 30 %, at least 40 %, at least 50 %, at least 60 %, at least 70 % at least 80 % at least 90 % or at least 95 %. In certain embodiments the EE % is from 50 % to 99 %. For example the EE % is from 70 % to 95 %. Thus it may be that the EE % is from 70% to 85 %.

[0134] In other embodiments, the anionic lipid composition does not comprise a pharmaceutically active agent.

[0135] The anionic lipid composition (e.g. the liposome composition) comprises negatively charged lipids (anionic lipids). In embodiments, the anionic lipid composition (e.g. the liposome composition) further comprises one or more neutral or zwitterionic lipids. In embodiments, the anionic lipid composition (e.g. the liposome composition) further comprises zwitterionic lipids. Thus, it may be that the anionic lipid composition (e.g. the liposome composition) comprises negatively charged lipids and zwitterionic lipids. In embodiments, the anionic lipid composition (e.g. the liposome composition) further comprises cholesterol. Thus, it may be that the anionic lipid composition (e.g. the liposome composition) comprises negatively charged lipids and cholesterol. It may be that the anionic lipid composition (e.g. the liposome composition) comprises negatively charged lipids, zwitterionic lipids and cholesterol. In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises up to 100% mol / mol of negatively charged lipids, for example, about 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% mol / mol of negatively charged lipids relative to the remaining lipids in the anionic lipid composition. For example, it may be that the anionic lipid composition (e.g. the liposome composition) comprises about 15%, 16%, 17%, 18%, 19%, 20%, 21 %, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% mol / mol of negatively charged lipids relative to the remaining lipids in the anionic lipid composition. In preferred embodiments, it may be that the anionic lipid composition (e.g. the liposome composition) comprises about 25% mol / mol of negatively charged lipids relative to the remaining lipids in the anionic lipid composition. It may be that the anionic lipid composition (e.g. the liposome composition) comprises about 25% mol / mol of negatively charged lipids relative to the remaining lipids in the anionic lipid composition, wherein the remaining lipids include zwitterionic lipids and / or cholesterol.

[0136] In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn- g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1 ,2-distearoyl- sn-g / ycero-3-phospho-(T -rac-glycerol) (DSPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 -rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn- glycero-3-phospho-(1 -rac-glycerol) (DOPG), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn- glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero- 3-phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol- 3'-4'-5'-triphosphate) (DOPI-P3), or combinations thereof.

[0137] In embodiments the anionic lipid composition further comprises one or more neutral lipid or zwitterionic lipid, for example phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, dimyristoylphosphatidylcholine, dipalmitoylphosphatidylcholine, distearoylphosphatidylcholine, 1-palmitoyl-2-oleoylphosphatidylcholine, dioleoylphosphatidylcholine, dioleoylphosphatidylethanolamine, dimyristoylphosphatidylethanolamine, dipalmitoylphosphatidylethanolamine,Diphytanoylphosphatidylethanolamineslinoleoylphosphatidylethanolamine, egg yolk phosphatidylcholine or cholesterol, or combinations thereof. In embodiments, the anionic lipid composition further comprises cholesterol, or a phosphocholine lipid, or combinations thereof. In principle the anionic lipid composition may further comprise any suitable phosphocholine, for example a neutral or zwitterionic phosphocholine lipid. In embodiments, the anionic lipid composition further comprises cholesterol, or a phosphocholine lipid such as 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1 ,2-distearoyl-sn-glycero-3- phosphocholine (DSPC), or combinations thereof. In embodiments, the anionic lipid composition further comprises cholesterol, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), phosphatidylcholine (PC), 1,2- Dioleoyl-sn-glycero-3-phosphocholine (DOPC), or combinations thereof. In embodiments, the anionic lipid composition further comprises cholesterol, 1,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC), or 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), or combinations thereof.

[0138] In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises DPPC. In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises DSPG. In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises cholesterol. In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises DSPG and DPPC. In embodiments, the anionic lipid composition (e.g. the liposome composition) comprises DSPG and cholesterol. Thus, it may be that the anionic lipid composition (e.g. the liposome composition) comprises DSPG, DPPC and cholesterol.

[0139] In certain embodiments the anionic lipid composition (e.g. the liposome composition) comprises 20 to 50 mol% anionic lipids (e.g. DSPG) and 50 to 80 mol% of neutral or zwitterionic lipids. In some embodiments the anionic lipid composition (e.g. the liposome composition) comprises 20 to 50 mol% DSPG; and 50 to 80 mol% DPPC. In some embodiments the anionic lipid composition (e.g. the liposome composition) comprises 20 to 30 mol% DSPG; and 70 to 80 mol% DPPC. In some embodiments the anionic lipid composition (e.g. the liposome composition) comprises about 25% of DSPG and about 75% DPPC. In some embodiments the anionic lipid composition (e.g. the liposome composition)comprises 20 to 50 mol% anionic lipids (e.g. DSPG) and 50 to 80 mol% of neutral or zwitterionic lipids selected from DPPC and cholesterol. In some embodiments the anionic lipid composition (e.g. the liposome composition) comprises 20 to 30 mol% anionic lipids (e.g. DSPG) and 70 to 80 mol% of neutral or zwitterionic lipids selected from DPPC and cholesterol. In some embodiments the anionic lipid composition comprises 20 to 50 mol% DSPG, 40 to 50 mol% DPPC and 15 to 35 mol % cholesterol, wherein the sum of the mol% of DPPC, DSPG and cholesterol is 100 mol%. In some embodiments the anionic lipid composition comprises 20 to 30 mol% DSPG, 40 to 50 mol% DPPC and 25 to 35 mol % cholesterol, wherein the sum of the mol% of DPPC, DSPG and cholesterol is 100 mol%. In a particular embodiment the anionic lipid composition (e.g. the liposome composition) comprises a molar ratio of DPPC : cholesterol : DSPG of about 45:25:30.Polycationic Aggregation Agent

[0140] In embodiments, the polycationic aggregation agent comprises 2 or more separate positively charged sites at a pH range of between 6.0 and 8.0, for example, at a pH of 7.4. It may be that the polycationic aggregation agent comprises 5 or more positively charged sites at a pH range of between 6.0 and 8.0, for example, at a pH of 7.4. It may be that the polycationic aggregation agent comprises 10 or more positively charged sites at a pH range of between 6.0 and 8.0, for example, at a pH of 7.4. For example, it may be that the polycationic aggregation agent comprises 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30, or 31 , or more positively charged sites at a pH range of between 6.0 and 8.0, for example, at a pH of 7.4. In embodiments the polycationic aggregation agent is an polycationic organic compound. For example, the polycationic aggregation agent may be a polymer comprising 2 or more basic centres (i.e. groups which are partially or fully protonated at physiological pH (6.0 to 8.0)). The positively charged sites in the polycationic aggregation agent are separate charged sites in the polycationic aggregation agent, for example the amine groups in a di-, tri- or polyamine compound. As will be recognised by the skilled person the polycationic aggregation agent is not an inorganic ion such as Ca2+, Zn2+or Mg2+.

[0141] In embodiments, the polycationic aggregation agent is capable of complexing, through non-covalent interactions, with one or more molecules of opposite charge in the anionic lipid composition, to form an aggregate. Thus, the polycationic aggregation agent forms an aggregate with the anionic lipid composition. It may be that the anionic lipid composition comprises liposomes. Thus, it may be that the polycationic aggregation agent forms an aggregate with the liposomes.

[0142] Preferably the polycationic aggregation agent is soluble in water at physiological pH (i.e. about pH 7.4).

[0143] In embodiments, the composition comprises one or more polycationic aggregation agents as described herein. For example, it may be that the composition comprises two different polycationic aggregation agents. It may be that the composition comprises three different polycationic aggregation agents.

[0144] In embodiments, the polycationic aggregation agent is a pharmaceutically active agent. Thus, it may be that the polycationic aggregation agent is a pharmaceutically active agent as defined herein, which comprises 2 or more separate positively charged sites at a pH range of between 6.0 and 8.0, for example, at a pH of 7.4.

[0145] In embodiments, the polycationic aggregation agent is a polyamine. It may be that the polyamine is a straight chain. Alternatively, the polyamine may be branched.

[0146] In embodiments, the polyamine comprises a peptide or a polypeptide. It may be that the peptide or the polypeptide comprises a single type of amino acid. For example, it may be that the polyamine comprises polylysine, polyhistine, polyornithine or polyarginine. Alternatively, the peptide or the polypeptide may comprise at least 2, at least 3, at least 4, at least 5 or at least 6 different amino acids. In some embodiments, the polyamine or the polycationic aggregation agent is not a protein. Preferably, it may be that the polyamine is polyarginine.

[0147] In embodiments, the polycationic aggregation agent is a polycationic peptide. It may be that the polycationic aggregation agent is a polycationic anti-inflammatory peptide. It may be that the polycationic aggregation agent is a polycationic anti-fibrotic peptide. It may be that the polycationic aggregation agent is a polycationic anti-microbial peptide.

[0148] In embodiments, the polycationic aggregation agent is an anti-inflammatory agent. In embodiments, the anti-inflammatory agent is a polycationic peptide. Thus, it may be that the anti-inflammatory agent is a random copolymer comprising one or more amino acid groups. For example, it may be that the anti-inflammatory agent is a random copolymer comprising one or more amino acid groups selected from the group consisting of lysine, alanine, glutamic acid, and tyrosine, or combinations thereof. In embodiments the antiinflammatory agent is a 40 to 100 amino acid polymer comprising four amino acids selected from L-alanine, L-lysine, L-glutamic acid, and L-tyrosine. In embodiments the antiinflammatory agent is 40 to 100 amino acid polymer comprising four amino acids selected from L-alanine, L-lysine, L-glutamic acid, and L-tyrosine, in a molar ratio of 4.2 to 3.4 to 1.4 to 1.0. Thus, it may be that the anti-inflammatory agent is glatiramer or a pharmaceutically acceptable salt thereof, (e.g. glatiramer acetate). Therefore, in embodiments, the polycationicaggregation agent is glatiramer or a pharmaceutically acceptable salt thereof (e.g. glatiramer acetate (GA)).

[0149] In embodiments, the polycationic aggregation agent is a polycationic anti-microbial agent. In embodiments, the anti-microbial agent is a polycationic peptide. It may be that the anti-microbial agent is selected from the group consisting of cathelicidin, LL-37, polymyxin B (PMB), magainin, aminoglycoside antibiotics (e.g. tobramycin), apidaecin 1 b, Walk11.3 and murepavadin. Preferably, it may be that the anti-microbial agent is LL-37.

[0150] In further embodiments, the polycationic aggregation agent is a polycationic antiinflammatory agent selected from the group consisting of glatiramer, or a pharmaceutically acceptable salt thereof, for example glatiramer acetate.

[0151] In other embodiments, the polycationic aggregation agent is a polycationic anti- fibrotic agent.

[0152] In embodiments, the polycationic aggregation agent is a polyamine. It may be that the polyamine comprises one or more amino sugar residues. It may be that the polyamine comprises a polymer comprising one or more amino sugar residues, for example chitin or chitosan.

[0153] In embodiments, the polyamine comprises an aminoglycoside. It may be that the aminoglycoside is selected from the group consisting of: streptomycin, gentamicin, tobramycin, amikacin, dibekacin, sisomicin, netilmicin, neomycin (e.g. neomycin B, neomycin C or neomycin E), plazomicin, spectinomycin, kanamycin, tobramycin, apramycin, hygromycin B, fortimicin, and combinations thereof. In embodiments, the aminoglycoside is tobramycin.

[0154] In embodiments, the polycationic aggregation agent comprises chitosan, chitin, an aminoglycoside, poly(dimethyldiallylammonium chloride), poly(amindoamine) (PAMAM), inverse poly(amidoamine) (i-PAMAM), polypropylene imine) (PPI), a triazine-based polymer, polyallylamine, polyethyleneimine (branched or straight-chain), poly(dimethylaminoethyl acrylate), a peptide or a polypeptide (e.g. polylysine, polyhistidine, polyornithine, polyarginine), a polyquaternium ((a polyquat) such as starch derivatives with amino or ammonium groups), or any combination thereof.

[0155] In some embodiments the polycationic aggregation agent has an average molecular weight (e.g. weight-average molecular weight) of from about kDa to about 30 kDa, for example from about 3 kDa to about 15 kDa or from about 4 kDa to about 12 kDa.

[0156] In some embodiments the polycationic aggregation agent is a polyamine with 2 to 6 basic nitrogen atoms, for example a polyamine with 2 to 6 amine, alkyl amine or di-alkyl aminegroups. In embodiments the polycationic aggregation agent is selected from putrescine, cadaverine, spermidine, spermine, thermospermine, caldopentamine, and caldohexamine.

[0157] In embodiments, the polycationic aggregation agent is a dendrimer. Dendrimers are branched core-shell structures with a precisely defined number of focal points between the core and the shell, determining their generation (G1 , G2, G3, etc.). By displaying cationic terminal groups of the branches (e.g. lysine amino acids), the dendrimers described herein are positively charged.

[0158] Thus, in embodiments, the polycationic aggregation agent is a poly(amidoamine) (PAMAM) dendrimer, an inverse poly(amidoamine) (i- PAM AM) dendrimer, a polypropylene imine) (PPI) dendrimer, a triazine dendrimer, a phosphorus dendrimer, or a peptide dendrimer. In preferred embodiments, it may be that the polycationic aggregation agent is a peptide dendrimer. Preferably, it may be that the polycationic aggregation agent is i-PAMAM.In embodiments, the polycationic aggregation agent is a G1 , G2, G3 or G4 dendrimer. In embodiments, the dendrimer is a G2 or G3 dendrimer. Thus, it may be that the dendrimer is a G2 dendrimer. It may be that the dendrimer is a G3 dendrimer. In preferred embodiments, the polycationic aggregation agent is a G3 dendrimer.

[0159] In embodiments the polycationic aggregation agent is a dendrimer (e.g. any of the dendrimers described herein) with an average molecular weight (e.g. weight-average molecular weight) is from about 2 kDa to about 20 kDa, for example from about 3 kDa to about 15 kDa or from about 4 kDa to about 12 kDa.

[0160] In embodiments, the polycationic aggregation agent is a dendrimer which comprises an amino acid selected from the group consisting of lysine, leucine, arginine, asparagine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof. It may be that the dendrimer comprises an amino acid selected from the group consisting of lysine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof.

[0161] In embodiments, the polycationic aggregation agent is a dendrimer described by a general formula (A)s-(B)4-(C)2-Z, wherein:A is XIAX2X3;B is X1BX4X5X6X7;C is XiBXsXsXyXeXy; and wherein:X is selected from lysine, and arginine;XIB is lysine;X2is selected from leucine, norleucine and alanine;Xa is absent or tyrosine;X4 is selected from lysine, arginine and alanine; each X5 is independently selected from lysine, leucine and alanine; each Xe is independently absent or lysine; each X7 is independently absent, glutamic acid or alanine;Xs is selected from lysine, tyrosine, leucine, arginine and glutamic acid; andZ is a core moiety.

[0162] In embodiments, A is selected from: KL, kl, rl, KA and k{NLE}y (SEQ ID NO: 91).

[0163] In embodiments, B is selected from: KKL, kkl, krl, KAK and KKAKE (SEQ ID NO: 92).

[0164] In embodiments, C is selected from: KKL, kll, krl, KEKA (SEQ ID NO: 93) and KYKAKA (SEQ ID NO: 94).

[0165] In embodiments, Z comprises from 1 to 10 amino acids, optionally wherein Z comprises one or more C2-C30 alkyl groups.

[0166] In embodiments, the polycationic aggregation agent is a dendrimer as described in Angew. Chem. Int. Ed. 2021 , 60, 26403-2640813, which is incorporated herein by reference. In embodiments, the polycationic aggregation agent is a dendrimer which comprises one of the following linear notations: (KA)s(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4), (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8), (ACKA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 9 to 12), (KAEKAYA)4(KEKYAKA)2KEKYKA-NH2(consisting of SEQ ID NO: 13 to 15), (AKA)8(KYEK)4(KEKA)2KAKY-OH (consisting of SEQ ID NO: 16 to 19), (ACKA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 20 to 23), (AK)8(KAKAKY)4(KAKEYEY)2KAKEYEY-NH2 (consisting of SEQ ID NO: 24 to 27), (KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 28 to 30), (AK)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 31 to 34),(KK)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 35 to 38),(KA)8(KKKAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 39 to 42), (ACKA)8(KKKAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 43 to 46),(FumKA)8(KKKAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 47 to 50),((KA)8(KAK)4(KEKA)2KAKEAYCA-NH2)2 (consisting of SEQ ID NO: 51 to 54), or(KA)8(KAK)4(KEKA)2KAKEAYC(FI)A-NH2 (consisting of SEQ ID NO: 55 to 58). In embodiments, the polycationic aggregation agent is a dendrimer which comprises one of the following sequences listed in Table 1.Table 1 - Linear notation of dendrimers of the invention and breakdown of the dendrimers into their respective linear amino acid chain core and branch sequences.

[0167] In embodiments, the polycationic aggregation agent is a dendrimer which comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4), (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). In embodiments, the polycationic aggregation agent is a dendrimer which comprisesthe following linear notation: (k{NLE}y)s(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (k{NLE}y)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (KL)8(KKL)4(KLL)2KK(Ci6)K(Ci6) (consisting of SEQ ID NO: 71 to 74). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (kl)s(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78). In embodiments, the polycationic aggregation agent is a dendrimer which comprises the following linear notation: (rl)s(krl)4(krl)2kk(Cis) (consisting of SEQ ID NO: 79 to 82).

[0168] In embodiments, the polycationic aggregation agent is selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straightchain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, Walk11.3, or a dendrimer which comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4),(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8),(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70), (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74), (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78), and (rl)s(krl)4(krl)2kk(Cis) (consisting of SEQ ID NO: 79 to 82). It may be that the polycationic agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), LL-37, and polyarginine.

[0169] In preferred embodiments the polycationic aggregation agent is substantially nontoxic to human osteoarthritis synovial fibroblasts (OASF). The toxicity of the polycationic aggregation agent may be assessed in-vitro using a cell viability assay as described in the Examples herein. In certain embodiments incubating the OASFs with 50 pg / mL of the polycationic aggregation agent for 48 hours results in a cell viability of at least 60 %, preferably at least 70% and more preferably at least 75 %.Pharmaceutically active agent

[0170] In embodiments, the composition comprises at least one pharmaceutically active agent. Thus, it may be that the composition comprises one pharmaceutically active agent. It may be that the composition comprises more than one pharmaceutically active agent. It may be that the composition may comprise two or more pharmaceutically active agents For example, the composition may comprise two, three or four pharmaceutically active agents.

[0171] In embodiments, the pharmaceutically active agent is selected from a hydrophilic pharmaceutically active agent, or a hydrophobic pharmaceutically active agent. Thus, it may be that the pharmaceutically active agent is a hydrophilic pharmaceutically active agent. Accordingly, it may be that the pharmaceutically active agent is water soluble. In other embodiments, it may be that the pharmaceutically active agent is a hydrophobic pharmaceutically active agent. Accordingly, it may be that the pharmaceutically active agent is a lipophilic pharmaceutically active agent.

[0172] In some embodiments, the pharmaceutically active agent is water soluble. By “soluble”, it is meant that 1 g of the pharmaceutically active agent requires less than 10,000 mL, preferably less than 1 ,000 mL, more preferably less than 100 mL, even more preferably less than 30 mL or 10 mL of solvent to dissolve at a given pH (at 25.0 ± 0.5 °C). It may be that by “soluble”, it is meant that the logP of the substance has a negative value. In embodiments, the pharmaceutically active agent is soluble in water at pH 7.0 and 25.0 ± 0.5 °C.

[0173] In other embodiments, the pharmaceutically active agent is water insoluble. By “insoluble” it is meant that 1 g of the pharmaceutically active agent requires more than 10,000 mL of solvent to dissolve at a given pH (e.g. at pH 7.0 and 25.0 ± 0.5 °C). It may be that by “insoluble”, it is meant that the logP of the substance has a positive value.

[0174] The pharmaceutically active ingredient is not particularly limited and can be selected by the skilled person according to the needs.

[0175] In embodiments, the composition may be for the use in the treatment of a joint disease or disorder. In embodiments, the composition may be for the use in inhibiting a joint disease or disorder, or preventing progression of the disease or disorder (e.g. osteoarthritis). Accordingly, the composition may comprise at least one pharmaceutically active agent selected from the group consisting of anti-inflammatory agents, anti-fibrotic agents, antimicrobial agents, non-steroidal anti-inflammatory agents, corticosteroids and biological agents (e.g. peptides, proteins, stem cells, antibodies and antibody fragments).

[0176] In embodiments, the pharmaceutically active agent is an anti-inflammatory agent. It may be that the anti-inflammatory agent is a corticosteroid, such as hydrocortisone. Corticosteroids are steroids that help reduce both inflammation and immune response. It maybe that the composition comprises a corticosteroid. It may be that the pharmaceutically active agent is a corticosteroid selected from hydrocortisone, prednisone, prednisolone, methylprednisolone, dexamethasone, triamcinolone, betamethasone, beclomethasone, flunisolide, and fluticasone.

[0177] In embodiments, the pharmaceutically active agent is an anti-inflammatory agent selected from the group consisting of quercetin, sinomenine, liquiritin, glatiramer acetate, rhein and Resolvin D1.

[0178] In embodiments, it may be that the pharmaceutically active agent is an anti-fibrotic agent. Thus, it may be that the composition comprises an anti-fibrotic agent, wherein the antifibrotic agent is selected from pirfenidone or nintedanib.

[0179] In embodiments, it may be that the pharmaceutically active agent is an anti-microbial agent. Thus, it may be that the composition comprises an anti-microbial agent, wherein the anti-microbial agent is selected from the group consisting of cathelicidin, LL-37, polymyxin B, magainin, murepavadin, G3KL, aminoglycoside antibiotic (e.g. tobramycin), apidaecin 1b, and Walk11.3.

[0180] In embodiments, the pharmaceutically active agent is a non-steroidal antiinflammatory agent, such as naproxen. Non-steroidal anti-inflammatory agents reduce pain, decrease inflammation, decrease fever, and prevent blood clots. It may be that the composition comprises a non-steroidal anti-inflammatory agent selected from the group consisting of naproxen, ibuprofen, diclofenac, celecoxib, meloxicam, or lornoxicam.

[0181] In embodiments the pharmaceutically active agent is a chondrogenesis inducer, for example angiopoietin-like 3 and derivatives thereof, such as LNA043 (described in Gerwin et al. Angiopoietin-like 3-derivative LNA043 for cartilage regeneration in osteoarthritis: a randomized phase 1 trial. Nat Med 28, 2633-2645 (2022). https: / / doi.org / 10.1038 / s41591- 022-02059-9).

[0182] In embodiments, the pharmaceutically active agent is a biological agent, for example, a peptide, protein, antibody, or antibody fragment. In embodiments, the pharmaceutically active agent is an antibody or functional fragment thereof. In embodiments, the pharmaceutically active agent is a peptide.

[0183] In embodiments, the pharmaceutically active agent is an antibody or functional fragment thereof, and is suitable for use in the treatment of a joint disease or disorder, for example, osteoarthritis.

[0184] The antibody or functional fragment thereof used in the composition is not particularly limited. In one embodiment, the antibody or functional fragment thereof is an antibody. Inanother embodiment, the antibody or functional fragment thereof is a functional fragment as defined herein. The antibody or functional fragment thereof may further comprise one or more modifications, e.g. in the form of added or substituted residues, that improve stability, specificity or targeting. These may include any such modifications that are known in the art.

[0185] The antigen against which the antibody or functional fragment is directed i.e. the immunogen, peptide, protein, or other molecular structure to which the antibody or functional fragment thereof can specifically bind, is not limited. In its most general form (and when no defined reference is mentioned), “specific to” or “specific binding” refers to the ability of the antibody or functional fragment thereof to discriminate between the target of interest and an unrelated biomolecule, as determined, for example, in accordance with specificity assay methods known in the art.

[0186] In embodiments, the antibody or functional fragment thereof is selected from antibodies specific to tumour necrosis factor alpha (TN Fa) and functional fragments thereof, antibodies specific to CD20 and functional fragments thereof, antibodies specific to interleukin 1 (IL-1), to interleukin 1 (IL-6), interleukin 1 beta (I L-1 P), or to their receptors and functional fragments thereof, antibodies specific to B-cell activating factor (BAFF), or to their receptors and functional fragments thereof, antibodies specific to Janus kinase (JAK) and functional fragments thereof. In embodiments, the antibody or functional fragment thereof is selected from infliximab, adalimumab, etanercept, certolizumab pegol, golimumab, canakinumab, belimumab, rituximab, anakinra and functional fragments thereof.

[0187] In embodiments, the pharmaceutically active agent is an anti-tumour necrosis factoralpha inhibitor (TNF inhibitors). It may be that the TNF inhibitor is selected from adalimumab, certolizumab, etanercept, golimumab, and infliximab. In embodiments, the pharmaceutically active agent is an anti-interleukin- 1 agent or an anti-interleukin- ip agent such as canakinumab, anakinra, ilonacept, or gevokizumab. In embodiments, the pharmaceutically active agent is a JAK inhibitor, such as tofacitinib, filgotinib, upadacitinib, TD-1473, Brepocitinib (PF-06700841), or PF-06651600.

[0188] In embodiments the pharmaceutically active agent is a NOD-like receptor protein 3 (NLRP3) antagonist, for example, DFV890, tranilast, 3,4-methylenedioxy-p-nitrostyrene (MNS), parthenolide, INF39, CY-09, MCC950 (PubChem CID 91826093), OLT1177 (dapansutrile) or oridonin. In some embodiments the pharmaceutically active agent is DFV890.

[0189] In embodiments, the pharmaceutically active agent is an immunosuppressant, such as rapamycin.

[0190] In embodiments, the pharmaceutically active agent is an mTOR inhibitor, such as torin-1 or torin-2.

[0191] In embodiments, the pharmaceutically active agent is a Bcr-Abl tyrosine kinase inhibitor, such as dasatinib.

[0192] In embodiments, the pharmaceutically active agent is a disease-modifying OA drug (DMOAD). It may be that the DMOAD is selected from the group consisting of teriparatide, zoledronic acid, denosumab, vitamin D, methotrexate, hydroxychloroquine, etanercept, tocilizumab, metformin, liraglutide, MIV-711 , TPX-100, XT-150, diacerein,GLPG1972 / S201086, sprifermin, TissueGene-C, lorecivivint, UBX0101, LNA043, LRX712, clodronate, kartogenin, dasatinib, quercetin, rhein, sinomenine, MK-8722, liquiritin, and rapamycin.

[0193] In embodiments, the pharmaceutically active agent is selected from the group consisting of triamcinolone, prednisone, hydrocortisone, methylprednisolone, dexamethasone, betamethasone, hyaluronic acid, certolizumab pegol, golimumab, belimumab, rituximab, rapamycin, torin-1 , torin-2, retinoic acid metabolism blocking agents (e.g. talarazole, liarozole), naproxen, ibuprofen, diclofenac, celecoxib, meloxicam, lornoxicam, kartogenin, dasatinib, quercetin, rhein, sinomenine, liquiritin, glatiramer acetate, insulin-like growth factor 1 (IGF 1), Resolvin D1 , fibroblast growth factor 18 (FGF 18), bone morphogenetic protein (BMP) 7, an anti-IL-1 agent (e.g. canakinumab, anakinra, ilonacept, gevokizumab), an anti-TNF agent (e.g. infliximab, adalimumab, etanercept), Botulinum toxin A, miRNA, mRNA, a JAK inhibitor (e.g. tofacitinib, filgotinib, upadacitinib, TD-1473, Brepocitinib (PF-06700841), PF-06651600), pirfenidone, nintedanib, cathelicidin, LL-37, polymyxin B, magainin, murepavadin, MK-8722, or combinations thereof.Other Additives

[0194] In embodiments, the compositions of the present invention may further comprise one or more imaging agents. It may be that the anionic lipid composition further comprises one or more imaging agents. For example, it may be that the imaging agents are trapped or encapsulated within the anionic lipid composition (e.g. the anionic liposomes), to allow their biodistribution to be studied after intraarticular administration to patients. Examples of such imaging agents include, but are not limited to, calcein, Fluorescein IsoThioCyanatedextran (MW 4000) (FITC-dextran), 8-hydroxy-1 , 3, 6-pyrene trisulfonate (HPTS), Rhodamine, lipid-in- Rhodamine, indocyanine green, long-chain dialkylcarbocyanine dye (e.g.

[0195] 1 ,T-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate, 1 , 1 '-didodecyl- 3,3,3',3'-tetramethylindocarbocyanine perchlorate, 1 , 1 '-dihexadecyl-3, 3, 3', 3'- tetramethylindocarbocyanine perchlorate, 1 ,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate, 1 ,1'-dioctadecyl-3,3,3',3'- tetramethylindocarbocyanine-5,5'-disulfonic acid, 1 , 1 ’-dioctadecyl-6,6’- di(4-sulfophenyl)-3,3, 3’,3’-tetramethylindocarbocyanine, 1 ,1 ’-dioctadecyl-3, 3, 3’,3’-tetramethylindodicarbocyanine- 5,5’-disulfonic acid), 1 ,1 '-dioctadecyl-3, 3, 3', 3'-tetramethylindodicarbocyanine perchlorate, 4,4’-diisothiocyanatostilbene- 2,2’-disulfonic acid, disodium salt, or 1 ,1 '-dioctadecyl-3, 3,3', 3'- tetramethylindodicarbocyanine, 4-chlorobenzenesulfonate salt); or a long-chain dialkyl aminostyryl dye (e.g. 4-(4-(dihexadecylamino)styryl)-N-methylpyridinium iodide, 4-(4- (didecylamino)styryl)-N-methylpyridinium iodide or 3,3’-dioctadecyl-5,5’- di(4- sulfophenyl)oxacarbocyanine, sodium salt). In embodiments, the anionic lipid composition further comprises a charge imparting membrane additive, for example, an additive that imparts a negative charge to the lipid vehicle such as dicetyl phosphate (dihexadecyl phosphate, DCP)). Thus, it may be that the anionic lipid composition further comprises DCP.

[0196] In embodiments the composition further comprises one or more additional additives selected from, buffers, antioxidants, preservatives, viscosity modifying agents, or surfactants, or combinations thereof.Uses

[0197] Also provided herein, is the use of a composition comprising an anionic lipid composition and a polycationic aggregation agent, as a carrier for a pharmaceutically active agent, wherein the composition is administered intraarticularly. In embodiments, it may be that the pharmaceutically active agent is dispersed or dissolved in the anionic lipid composition.

[0198] Also provided, is the use of an aggregated composition comprising an anionic liposome and a cationic dendrimer aggregation agent, as a carrier for a pharmaceutically active agent. In embodiments, it may be that the pharmaceutically active agent is encapsulated in the anionic liposome.

[0199] The compositions described herein provide sustained and controlled release of the pharmaceutically active agent with a tuneable window of duration. The composition is therefore highly suitable for the formation of depot compositions following intraarticular administration to joints, and are formed from lipids which may provide inherent benefits in themselves in addition to forming highly effective carriers and depots for active agents. For example, the compositions described herein lubricate cartilage and show improved retention on the cartilage surface.

[0200] Thus, an advantage of the controlled release depots of the present invention is that the pharmaceutically active agents are released gradually over long periods without the need for repeat dosing.

[0201] The compositions of the present invention may form depots where the pharmaceutically active agent is slowly released at the cartilage surface. It is particularly significant that the compositions of the claimed invention are aggregated compositions, as the size of the aggregates reduces clearance from the joint space. Thus, the compositions of the present invention advantageously display enhanced cartilage retention and / or enhanced cartilage lubrication compared to the intraarticular administration of liposomes alone.

[0202] Also provided herein, is the use of a pre-formulation composition comprising an ionic lipid composition (e.g. an anionic liposome) and a pharmaceutically active agent for the manufacture of a composition of the invention.

[0203] In embodiments, the pharmaceutically active agent in the pre-formulation is a hydrophilic pharmaceutically active agent, as described herein.Therapeutic Uses and Applications

[0204] The composition of the invention may be used to treat, alleviate, retard, prevent, manage or cure any articular disorder or symptoms arising there from which is associated with joint dysfunction. For the purposes of this disclosure the term "articular disorder" shall be held to mean any affliction (congenital, autoimmune or otherwise), injury or disease of the articular region which causes degeneration, pain, reduction in mobility, inflammation or physiological disruption and dysfunction of joints. The disorder may be associated with reduced joint secretion and lubrication as well as from complications of knee and hip replacement.

[0205] The “joint” in accordance with the invention may be any one of the knee, hip, ankle, shoulder, elbow, tarsal, carpal, interphalangeal and intervertebral.

[0206] The compositions of the invention include aggregated compositions which comprise an anionic composition, a polycationic aggregated agent, and a pharmaceutically active agent, to target release of the pharmaceutically active agent to the joint of a subject, particularly to the synovium, synovial fluid, and / or cartilage. The composition of the invention may advantageously be used for intraarticular delivery of pharmaceutically active agents, by forming a sustained release depot in situ, i.e. at the surface of the cartilage.

[0207] Accordingly, the compositions according to the invention comprising a pharmaceutically active agent for local treatment of the joint are expected to be useful in the treatment or prevention of a joint disease or disorder. In embodiments, the composition of the invention is for use in the treatment or prevention of a condition affecting the joint, including the synovium, synovial fluid, cartilage, tendons, ligaments and bone within the joint. In embodiments, the composition of the invention is for use in the treatment or prevention of a condition affecting the joint, including the synovium. In embodiments, the composition of theinvention is for use in the treatment or prevention of a condition affecting the synovial fluid. In embodiments, the composition of the invention is for use in the treatment or prevention of a condition affecting the cartilage.

[0208] It may be that the composition does not comprise a pharmaceutically active agent. Thus, it may be that the composition comprises an anionic lipid composition, and a polycationic aggregation agent, and can be useful in the prevention or treatment of a joint disease or disorder, particularly conditions affecting the cartilage.

[0209] In other embodiments, it may be that the composition comprises a pharmaceutically active agent. Thus, it may be that the composition comprises an anionic lipid composition, a polycationic aggregation agent, and a pharmaceutically active agent, and be useful in the prevention or treatment of a joint disease or disorder, particularly conditions affecting the cartilage.

[0210] In one aspect of the invention there is provided a composition (e.g. an aggregated composition) of the invention for use in the treatment or prophylaxis of a joint disease or disorder. In embodiments, the composition of the invention for use in inhibiting or preventing progression of the joint disease or disorder. It may be that the joint disease or disorder is selected from the group consisting of: arthritis, osteoarthritis, arthrofibrosis, rheumatoid arthritis, gout, bursitis, bacterial arthritis, juvenile idiopathic arthritis, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, tendinopathy, polymyalgia rheumatica, Paget’s disease, lupus, Sjogren's Syndrome, osteonecrosis, neuropathic arthropathy, or Lyme disease.

[0211] Thus, in embodiments, the composition of the invention is for use in the treatment or prophylaxis of arthritis, osteoarthritis, arthrofibrosis, rheumatoid arthritis, gout, bursitis, bacterial arthritis, juvenile idiopathic arthritis, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, tendinopathy, polymyalgia rheumatica, Paget’s disease, lupus, Sjogren's Syndrome, osteonecrosis, neuropathic arthropathy, or Lyme disease.

[0212] The most common forms of arthritis are osteoarthritis and rheumatoid arthritis. Osteoarthritis can affect any joint in the body. Most commonly it affects joints in the fingers, toes, wrist, knees, and hips but can also affect other joints, including the joints in the spinal column and, following a traumatic injury, can affect the shoulder, ankles and, rarely, the elbow. Rheumatoid arthritis often affects joints in the hands and feet. Accordingly, the composition of the invention may be useful in the treatment of both of these conditions, in addition to osteoarthritis in rheumatoid arthritis patients.

[0213] Osteoarthritis (OA) is a debilitating chronic joint disease characterised by the degradation of articular cartilage, synovial fibrosis, and low-grade inflammation. OA also perturbs the function of synovial fibroblasts (SFs) in the joint synovial membrane. SFssignificantly contribute to cartilage damage in OA, and synovial fibrosis is associated with chronic joint pain.

[0214] Thus, in embodiments, the composition of the invention is for use in the treatment of osteoarthritis. In embodiments, the composition of the invention is for use in inhibiting or preventing progression of osteoarthritis, such as the degeneration processes in the cartilage tissue. In embodiments, the composition of the invention is for use in the treatment of synovial fibrosis. In embodiments the composition of the invention is for use in reducing or inhibiting cartilage degradation. In embodiments the composition of the invention is for use in reducing or inhibiting synovial inflammation. In embodiments the composition of the invention is for use in reducing or inhibiting osteophytes. In embodiments the composition of the invention is for use in reducing or inhibiting joint swelling. In embodiments the composition of the invention is for use in reducing or inhibiting pain associated with a joint disease such as OA.

[0215] In further embodiments, the composition of the invention is useful in the treatment of traumatic joint injury, sports injury, locked joint (such as in temporomandibular joint (TMJ)), and status post-surgical intervention such as arthrocentesis, arthroscopic surgery, arthroplasty, knee and hip replacement.

[0216] In preferred embodiments, the condition to be treated or prevented by the infection is primary or secondary osteoarthritis.

[0217] In a further embodiment, there is provided a composition of the invention for use in a method of lubricating a joint of a subject. In a further embodiment, there is provided a composition of the invention for use in a method of lubricating cartilage. The composition is administered to the subject intraarticularly. In embodiments, the composition is administered intraarticularly into a cavity of the joint. In embodiments, the composition does not comprise a pharmaceutically active agent. Thus, it may be that the composition comprises an anionic lipid composition, and a polycationic aggregation agent, and be useful in a method of lubricating a joint of a subject. In other embodiments, the composition comprises a pharmaceutically active agent. Thus, it may be that the composition comprises an anionic lipid composition, a polycationic aggregation agent, and a pharmaceutically active agent, and be useful in a method of lubricating a joint of a subject.

[0218] In a further embodiment, there is provided a composition of the invention for use in a method of enhancing joint lubrication and / or preventing joint wear in a subject. In embodiments, the composition is administered intraarticularly into a cavity of the joint. It may be that the composition of the invention is useful in a method of enhancing joint lubrication in a subject. It may be that the composition of the invention is useful in a preventing joint wear in a subject. In embodiments, the composition does not comprise a pharmaceutically activeagent. Thus, it may be that the composition comprises an anionic lipid composition, and a polycationic aggregation agent, and be useful in a method of enhancing joint lubrication and / or preventing joint wear a subject. In other embodiments, the composition comprises a pharmaceutically active agent. Thus, it may be that the composition comprises an anionic lipid composition, a polycationic aggregation agent, and a pharmaceutically active agent, and be useful in a method of enhancing joint lubrication and / or preventing joint wear in a subject.

[0219] The composition of the present invention may be used exclusive of, or as an adjunct to, anti-inflammatory agents, analgesic agents, muscle relaxants, antidepressants, or agents that promote joint lubrication commonly used to treat disorders associated with joint stiffness, such as arthritis. A combined therapeutic approach may be beneficial in reducing side effects associated with agents, such as non-steroidal, anti-inflammatory drugs (NSAIDs), commonly used to prevent, manage, or treat disorders such as osteoarthritis associated with reduced joint lubrication. In addition to enhancing safety, a combined therapeutic approach may also be advantageous in increasing efficacy of treatment.

[0220] It is to be understood that methods of treatment corresponding to any of the uses of the composition in the treatment of osteoarthritis described herein are intended to be encompassed within the invention. Similarly, any of the uses described herein may be described in relation to the use of the composition in the manufacture of a medicament for use in any of the treatments of osteoarthritis described herein. The invention encompasses all such corresponding uses in the manufacture of a medicament.

[0221] It is also to be understood that the composition of the invention also encompassed the aggregated compositions of the invention, as described herein. In preferred embodiments in any of the uses and methods of treatment described herein the composition administered to the subject is an aggregated composition as described herein, that is a composition comprising aggregates formed between the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent.Dosage and Dosage Regimens

[0222] The amount of pharmaceutically active agent to be formulated with the compositions of the present invention will depend upon the functional dose and the period during which the depot composition formed upon administration is to provide sustained release. Typically, the dose formulated for a particular pharmaceutically active agent will be around the equivalent of the normal single dose multiplied by the number times greater the expected duration of action the formulation is to provide. Evidently, this amount will need to be tailored to take into account any adverse effects of a large dose at the beginning of treatment and so this will generally bethe maximum dose used. The precise amount suitable in any case will readily be determined by suitable experimentation.

[0223] It may be that the composition of the invention is administered intraarticularly. The duration of treatment will depend upon the nature of the disease or disorder being treated. Suitably, the intraarticular administration is continued until the condition is eradicated and / or the symptoms of the condition are reduced or eliminated. The upper limit of the period of treatment can be readily determined by a physician. For example, it may be that the composition is administered intraarticularly from weekly to yearly, preferably fortnightly to half- yearly, more preferably monthly to quarterly.

[0224] The frequency of administration of the composition of the invention will depend upon a number of factors that may readily be determined by a physician, for example the severity of the condition, the responsiveness to initial treatment and the particular condition being treated. For example, it may be that the composition is intraarticularly administered once a week. It may be that the composition is intraarticularly administered more than once a week.For example it may be that the composition is administered intraarticularly once or twice per day. In some embodiments the composition is administered intraarticularly once per day. In some embodiments the composition is administered intraarticularly once every other day. It may be that the composition is intraarticularly administered once a month. It may be that the composition is intraarticularly administered once every six weeks. It may be that the composition is intraarticularly administered once every three months. It may be that the composition is intraarticularly administered once every four months. It may be that the composition is intraarticularly administered twice a year. It may be that the composition is intraarticularly administered once a year.

[0225] The dosage of the pharmaceutically active agent administered with the composition of the invention will vary depending upon a number of factors including, for example the age, weight and gender of animal or human suffering from the condition, the severity of the condition and the selected administration frequency.

[0226] A suitable dosage for intraarticular application can be readily determined by a physician. The dosage must be effective to achieve an improvement in the lubrication of the treated joint, namely, to reduce friction between the cartilages forming the joint, the improvement may be exhibited by clinical tests as well as by an improvement in the well-being of the subject undergoing said treatment (e.g. reduced pain in the afflicted joint, improvement in mobility). The effective amount is typically determined in appropriately designed clinical trials (dose range studies) and the person versed in the art will know how to properly conduct such trials in order to determine the effective amount.Routes of Administration

[0227] The composition of the invention may be administered to a subject by any suitable route of administration, appropriate for the condition to be treated and the pharmaceutically active agent to be used.

[0228] Routes of administration include, but are not limited to, parenteral, for example, by injection, including subcutaneous, intradermal, intramuscular, intravenous, intraarterial, intracardiac, intrathecal, intraspinal, intracapsular, subcapsular, intraorbital, intraperitoneal, intratracheal, subcuticular, intraarticular, subarachnoid, and intrasternal. The composition administered by the above routes of administration may be any of the compositions described herein. In an embodiment the composition comprises a composition comprising an anionic liposome; and a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82), and optionally wherein the aggregated composition further comprises a pharmaceutically active agent. In a preferred embodiment the composition comprises a composition comprising an anionic liposome; and a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8), and optionally wherein the aggregated composition further comprises a pharmaceutically active agent. Suitably the composition comprises aggregates comprising the cationic dendrimer aggregation agent and 2 or more of the anionic liposomes.

[0229] In embodiments, the composition of the invention is a parental composition. Thus, it may be that the composition of the invention is an injectable formulation and is administered to the subject subcutaneously, intramuscularly, intraarticularly or intradermally. Preferably, the composition is administered to the subject intraarticularly.

[0230] In embodiments, the composition of the invention is administered via arthroscopic administration.

[0231] Accordingly, the composition of the invention is in the form of a liquid preparation, which is suitable as an injectable formulation, particularly an intraarticular injectableformulation. Thus, it may be that the composition of the invention is a liquid preparation such as a gel, or a sterile aqueous or oily solution.

[0232] In embodiments, the composition of the invention is suitable for intraarticular administration, and thus, the composition has a viscosity of at least about 0.01 Pa s or at least about 0.1 Pa s, preferably at least about 1 Pa s, more preferably up to about 10 Pa s. For example the composition has a viscosity of at least about 0.5 Pa s to about 8 Pa s.. This viscosity may be measured using a viscometer at a shear rate of 0.1 / second.

[0233] In certain embodiments the composition of the invention is suitable for intraarticular injection through a 20 to 30 gauge needle. For example, a 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29, or 30 gauge needle.

[0234] Intraarticular administration has the advantage that the composition according to the invention is administered directly into the synovial fluid in the vicinity of the joint cartilage and is also able to diffuse from there into the cartilage tissue. Compositions according to the invention can thus also be injected directly into the joint gap and thus develop their action directly at the site of action as intended, for example, onto the joint cartilage.

[0235] The compositions of the invention may be adapted for administration by the intraarticular route. For example, the compositions may further include aqueous and nonaqueous sterile injection solutions comprising antioxidants, buffers, bacteriostatics and solutes, by means of which the composition is rendered isotonic with the synovial fluid of the recipient to be treated; as well as aqueous and non-aqueous sterile suspensions, which can comprise suspension media and thickeners. The compositions can be delivered in singledose or multi-dose containers, for example sealed ampoules and vials, and stored in the freeze-dried (lyophilised) state, so that only the addition of the sterile carrier liquid, for example water for injection purposes, immediately before use is necessary. Injection solutions and suspensions prepared in accordance with the composition can be prepared from sterile powders, granules and tablets.Subject

[0236] The compositions of the invention are suitable for use in the treatment of a subject affected by any of the diseases or conditions described herein. Preferably, the compositions of the invention are suitable for use in the intraarticular treatment of a subject affected by any of the diseases or conditions described herein, wherein the composition is applied intraarticularly to the joint of a subject.

[0237] In embodiments, the subject may be a warm-blooded mammal. In particular embodiments, the subject treated is a human. It may be that the subject is an adult human(aged 18 years or more). It may be that the subject is a paediatric human aged less than 18 years. It may be that the paediatric subject is aged from 2 to 4 years. It may be that the paediatric subject is aged from 5 to 10 years. It may be that the paediatric subject is aged from 11 to 18 years.

[0238] In embodiments, the subject may be an animal. In certain embodiments, the composition of the invention is for use as veterinary product for the topical treatment of an animal. In certain embodiments, the compositions of the invention are for use in the topical treatment of diseases and conditions in commercial animals such as livestock (e.g. cows, sheep, etc.). In other embodiments, the compositions of the present invention may be for use in the topical treatment of diseases or conditions in companion animals such as cats, dogs, horses, etc.Method of Preparation

[0239] The composition of the invention may be prepared by mixing together the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent as illustrated in the Examples. In certain embodiments the composition of the invention may be prepared by mixing an aqueous solution of anionic liposomes with a solution of polycationic aggregation agent (e.g. a dendrimer such as Dendril or Dendri4). The mixing is suitably carried out at a pH of about 7.0 to about 8.0 (e.g. about pH 7.4). Optionally the mixing takes place in the presence of a suitable buffer, such as HEPES to maintain the pH at the desired level during mixing and aggregation of the anionic lipids with the polycationic aggregation agent. Optionally the mixing takes place in the presence of sodium chloride to aid aggregation. Suitably the concentration of sodium chloride in the mixture is from about 100 mM to about 150 mM, for example about 135 mM to about 145 mM. The mixing of the anionic lipid and the polycationic aggregation agent is suitably performed at ambient temperature, for example from about 20 °C to about 25 °C. Aggregation may be monitored by assessing the turbidity of the mixture and / or by optical microscopy.

[0240] In preferred embodiments the composition of the invention is sterile. The composition may be sterilised following mixing of the anionic lipid composition (e.g. liposomes) with a solution of polycationic aggregation agent to form an aggregated solution using conventional methods, for example terminal sterilisation using radiation (e.g. gamma radiation, electron beam sterilisation or ultraviolet light). It may be that the aggregated composition is added to a suitable container (e.g. a glass vial) which is sealed and sterilised. Alternatively sterile solutions of the anionic lipid composition (e.g. liposomes) and polycationic aggregation agent are prepared prior to mixing the solutions. The solutions of the anionic lipid composition and the polycationic aggregation agent are then mixed under aseptic conditions to provide the finalsterile aggregated composition. The solution of anionic lipid composition and the solution of polycationic aggregation agent may be prepared as sterile solutions using well-known methods, for example by sterile filtration of each solution.Kits

[0241] Provided herein is a kit comprising: a) a first container comprising an anionic lipid composition; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use as defined herein.

[0242] In embodiments, the first container further comprises a pharmaceutically active agent incorporated into the anionic lipid composition. Thus, it may be that the kit comprises: a) a first container comprising an anionic lipid composition, wherein the anionic lipid composition comprises a pharmaceutically active agent; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use as defined herein.

[0243] In embodiments, the anionic lipid composition is selected from any of the anionic lipid compositions described herein. For example, it may be that the anionic lipid composition comprises liposomes. Thus, the first container may comprise an anionic liposome composition, wherein a pharmaceutically active agent is encapsulated in the liposomes.In embodiments, the polycationic aggregation agent is selected from any of the polycationic aggregation agents described herein. For example, it may be that the polycationic aggregation agent is a pharmaceutically active agent. In other embodiments, it may be that the polycationic aggregation agent is a dendrimer as described herein, such as a peptide dendrimer. In embodiments, it may be that the polycationic aggregation agent is a dendrimer comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82). In preferred embodiments, it may be that the polycationic aggregation agent is a dendrimer comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). It may be that the polycationic aggregation agent is selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walkl 1.3. Thus, it may be that the polycationic aggregating agent is: (i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), LL-37, and polyarginine.

[0244] In embodiments, the anionic lipid composition in the first container is provided as a lyophilised mixture. In embodiments, the anionic lipid composition and the pharmaceutically active agent in the first container are provided as a lyophilised mixture. Similarly, the polycationic aggregation agent may also be lyophilised. It may be that the lyophilised mixture is obtained by methods known to those skilled in the art. Thus, it may be that the kit comprises instructions to hydrate the lyophilised mixture, in order to arrive at the composition of the invention. Suitably the lyophilised components present in the kit are hydrated with sterile water or saline (e.g. sterile phosphate buffered saline).

[0245] In further embodiments, also provided is a kit comprising: a) a first container comprising an anionic liposome; b) a second container comprising a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); and c) instructions to combine a) with b) to provide the aggregated composition as defined herein.

[0246] In embodiments, the first container further comprises a pharmaceutically active agent incorporated into the anionic liposome, for example, wherein the pharmaceutically active agent is encapsulated within the anionic liposome.

[0247] In embodiments, the anionic liposome is selected from any of the anionic liposomes described herein. In embodiments, the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78). In embodiments, the cationic dendrimer aggregation agent comprises the following linear notation: (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82).

[0248] In embodiments, the anionic liposome in the first container is provided as a lyophilised mixture. In embodiments, the anionic liposome and the pharmaceutically active agent in the first container are provided as a lyophilised mixture. It may be that the lyophilised mixture is obtained by methods known to those skilled in the art. Thus, it may be that the kit comprises instructions to hydrate the lyophilised mixture, in order to arrive at the aggregated composition of the invention.

[0249] In embodiments the composition of the invention may be prepared by connecting the first container with the second container and causing the anionic lipid composition and the polycationic aggregation agent to mix together to form the aggregated composition. For example the first container may comprise a first syringe comprising an aqueous solution of the anionic lipid composition and the second container may comprise a second syringe comprising an aqueous solution of the polycationic aggregation agent. Mixing of the two solutions may be achieved by connecting the first syringe with the second syringe and cycling the mixture from one syringe to the other thereby forming the aggregated composition. Alternatively the first and second containers may be separate barrels in a double barrel syringe system. Mixing may be effected by ejecting the contents of each barrel into a common exit channel in fluidcommunication with both barrels such that the contents of each barrel mix with one another in the exit channel to form an aggregated mixture.EXAMPLES

[0250] Solvents, reagents and starting materials were purchased from commercial vendors and used as received unless otherwise described. All reactions were performed at room temperature unless otherwise stated. Starting materials were purchased from commercial sources or synthesised according to the methods described herein or using literature procedures.AbbreviationsALs: Aggregated liposomesCOF: Coefficient of frictionDendriXs - Dendril and / or Dendri4DendriXAL - Dendrimer-aggregated liposomesDIC: N,N’-diisopropyl carbodiimideDiD: 1 ,T-Dioctadecyl-3,3,3’,3’-tetramethylindodicarbocyanine, 4-chlorobenzenesulfonate saltDLS: Dynamic light scatteringDMEM: Dulbecco's modified Eagle's mediumDMF: N,N-dimethylformamideDODT : 2,2’-(Ethylenedioxy)diethanethiolDPBS: Dulbecco's phosphate-buffered salineDPPC: 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholineDSPG: 1 ,2-distearoyl-sn-glycero-3-phospho-(10-rac-glycerol) sodium saltEDTA: Ethylenediaminetetraacetic acidFBS: Fetal bovine serumFCS: Fetal calf serumHEPES: 4-(2-hydroxyethyl)-1 -piperazineethanesulfonic acid min: minute(s)HPLC: High performance liquid chromatographyLC-MS : Liquid chromatography-mass spectrometryMeCN: AcetonitrileOA: OsteoarthritisOASFs: Osteoarthritis synovial fibroblastsPBS: Phosphate-buffered salinePDI: PolydispersityPI: propidium iodideRP-HPLC: Reverse phase-high performance liquid chromatographySF: Synovial fibroblastsTIS: TriisopropylsilaneTEM : Transmission electron microscopyTFA: Trifluoroacetic acidMaterials

[0251] The phospholipids 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1 ,2- distearoyl-sn-glycero-3-phospho-(10-rac-glycerol) sodium salt (DSPG) were kindly given by Lipoid (Ludwigshafen, Germany). A HEPES solution (1 M) was obtained from Carl Roth® (Karlsruhe, Germany). 1 ,T-Dioctadecyl-3,3,3’,3’-tetramethylindodicarbocyanine, 4- chlorobenzenesulfonate salt (Di D, catalog number: D7757) was obtained from Thermo Fisher Scientific™ (Waltham, MA, USA). DMF (N,N-dimethylformamide) was purchased from Thommen-Furler AG (Switzerland), Oxyma Pure (hydroxyiminocyanoacetic acid ethyl ester) from SENN AG (Switzerland), DIC (N,N’-diisopropyl carbodiimide) from Iris BIOTECH GMBH (Germany) and piperidine from Acros Organics (Thermo Fisher Scientific™, USA). DODT (2,2’-(Ethylenedioxy)diethanethiol) was obtained from Merck® (Germany), while triisopropylsilane and trifluoroacetic acid were purchased from Fluorochem Ltd (United Kingdom). All amino acids were supplied by Shanghai Space Peptides Pharmaceuticals Co., Ltd. Chemicals were used as supplied and solvents were of technical grade. Amino acids were used as the following derivatives: Fmoc-Lys(Boc)-OH, Fmoc-Lys(Fmoc)-OH, Fmoc-Glu(tBu)- OH, Fmoc-Gly-OH, Fmoc-Tyr(tBu)-OH, Fmoc-Cys(Trt)-OH. Rink Amide AM LL resin was purchased from Novabiochem® (Merck®, Germany). Ala- Wang resin was purchased from Iris BIOTECH GMBH. Porcine knee cartilage was procured from a regional abattoir located in Munchenbuchsee, Switzerland. Chloroform and methanol were purchased from FisherScientific (Schwerte, Germany). Water with a resistivity of 18.2 MQ.cm was generated using a Barnstead Smart2 pure system from Thermo Scientific™ (Pittsburgh, USA).Analytical MethodsReverse Phase-High Performance Liquid Chromatography (RP-HPLC)RP-HPLC was used to quantify the dendrimers. In particular, analytical RP-HPLC was performed with an Ultimate 3000 Rapid Separation LC-MS System (DAD-3000RS diode array detector) using an Acclaim® RSLC 120 C18 column (2.2 pm, 120 A, 3x50 mm, flow 1.2 mL / min) from Dionex. Data recording and processing was done with Dionex™ Chromeleon™ Management System Version 6.80 (analytical RP-HPLC). All RP-HPLC were using HPLC- grade acetonitrile and Milli-Q deionised water. The elution solutions were: A: MilliQ deionized water containing 0.05% TFA; D: MilliQ deionised water / acetonitrile (10:90, v / v) containing 0.05% TFA. Preparative RP-HPLC was performed with a Waters® automatic Prep LC Controller System containing the four following modules: Waters2489 UV / Vis detector, Waters2545 pump, Waters® Fraction Collector III and Waters® 2707 Autosampler. A Dr. Maisch® GmbH Reprospher® column (C18-DE, 100x30 mm, particle size 5 pm, pore size 100 A, flow rate 40 mL / min) was used. Compounds were detected by UV absorption at 214 nm using a Waters® 248 Tunable Absorbance Detector. Data recording and processing was performed with Waters® ChromScope™ version 1.40 from Waters Corporation®. The elution solutions were: A MilliQ deionised water containing 0.1 % TFA; D MilliQ deionized water / acetonitrile (10:90, v / v) containing 0.1 % TFA. MS spectra, recorded on a Thermo Scientific™ LTQ OrbitrapXL™.Dynamic Light Scattering (PLS) and Zeta Potential

[0252] DLS and zeta potential measurements were used to characterise the liposomes. The mean hydrodynamic diameter and polydispersity index (PDI) were measured with dynamic light scattering (DLS) analyser Litesizer 500 (Anton Paar, Austria) at 25 °C with a backscatter angle of 175° and a 658 nm laser. The zeta potential was assessed with laser Doppler microelectrophoresis using the same instrument and Omega cuvette (Anton Paar, Austria). Liposome stability was evaluated for 16 weeks at 4 °C. Formulations were used within 24 h from extrusion for all testing.Microscopic imaging of liposomes and DendriXALsTo evaluate the morphology, liposomes and DendriXALs were imaged using fluorescence and cryogenic transmission electron microscopy (cryo-TEM). To prepare for fluorescence microscopy, lipid films were stained with 0.05 mol% of the non-exchangeable lipophilic dye DiD, and liposomes and DendriXALs were prepared following the same method describedpreviously, while being shielded from light. Then, 20 pL of the formulations were placed on a slide and covered with a glass coverslip, and an inverted fluorescence microscope (Nikon Eclipse- Ti, Canada) was used to capture images through a Tx red filter. For cryo-TEM imaging, 6-8 pL of each sample was added onto a gold grid covered by a holey gold film (UltrAuFoil® 2 / 1 , Quantifoil® Micro Tools GmbH, Jena, Germany). The excess liquid was blotted automatically between two strips of filter paper or only from the backside of the grid. Subsequently, the samples were rapidly plunge-frozen in liquid ethane (cooled to 180 °C) in a Cryobox™ (Carl Zeiss NTS® GmbH, Oberkochen, Germany). Excess ethane was removed with a piece of filter paper, and the samples were immediately transferred with a Gatan™ 626 cryo-transfer holder (Gatan®, Pleasanton, USA) into the pre-cooled Cryo-electron microscope (Philips CM 120, Eindhoven, Netherlands) operating at 120 kV under low-dose conditions. The images were recorded with a 2k CMOS Camera (F216, TVIPS, Gauting, Germany), with four images being recorded and averaged into one image to minimise noise.Flow Cytometry

[0253] An imaging flow cytometer (ImageStream® X Mark II, Cytek Biosciences®, USA) was used for analysis of the uptake of aggregated liposomes (e.g. Dendri4Als) and liposomes into RAW264.7 cells.

[0254] Initially, the cell suspension was filtered to remove aggregates, followed by the addition of 100 ng / mL propidium iodide (PI, BioLegend®, USA) to label dead cells, and 5 pg / mL Hoechst reagent (Thermofisher Scientific™, USA) to label all cells. This mixture was then incubated for 3 min at 37 °C. Following this, the suspension was analysed using the flow cytometer, with a minimum of 5000 cells being measured for each sample. Subsequent gating was applied to select single, focused, and live cells, with the procedure ensuring that the count of live cells remained above 500 for all samples. Analysis and generation of histograms and statistics of DiD intensity were conducted using IDEAS® 6.3 software (Amnis Corporation®, USA). The fluorescence intensity of cells was normalised to the count. The signal from DMEM-treated cells was subtracted from both the liposome and aggregated liposome (e.g. Dendri4AL) samples, and the aggregated liposome (e.g. Dendri4AL) sample was further normalised to its respective liposome positive control.Fluorescent stereo microscope imaging

[0255] Fluorescent stereo microscope imaging (Zeiss AxioZoom® V16, Germany) was performed to analyse the cartilage surface in cartilage retention studies. Images were captured at 10X and 50X magnification with GFP and Cy5 filters. Fluorescence intensities were analysed using Zeiss's ZEN 2.5 software, focusing on a consistent area of interest on the cartilage surface.Tribology

[0256] The UMT-2 tribometer (Bruker®, USA) was utilised to investigate the friction behaviour of self-mated cartilage in the presence of measured samples, operating in linear reciprocating mode. The counterparts comprised two sections of porcine cartilage that were bonded to the upper and lower parts of the tribometer shortly before testing. During each experiment, the upper specimen (10x10 mm) was subjected to a 1 N load against the lower specimen (30x15 mm) and moved over a 2 mm stroke length at a frequency of 1 Hz for 10 minutes. The pair was fully immersed in the lubricant throughout the duration of the test. All tests were performed at a constant temperature of 20 °C and a data acquisition frequency of 500 Hz. The representative coefficient of friction (COF) of each test was determined from the raw data of lateral and normal force as the average of each friction loop, considering only the central 90% portion of each friction loop to avoid transients associated with the two ends of the stroke length. Additionally, the first 20% of the loops were disregarded to account for the steady-state friction behaviour of the self-mated contact, thus eliminating possible running-in transients.Statistical analysisAll experiments were conducted with a minimum of three replicates, except where noted otherwise. The presented values represent the mean ± standard deviation. General calculations were performed using Microsoft Excel, while GraphPad Prism 9.5 was utilised for generating graphs, executing one-way ANOVA, and conducting Tukey's test for multiple comparisons and unpaired t-test for single comparisons (except where noted otherwise).Methods - Dendrimer Preparation

[0257] Dendril has the linear notation: (KA)s(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4).

[0258] Dendri4 has the linear notation: (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

[0259] Dendril and Dendri4 (DendriXs) dendrimers were synthesized using standard 9- fluorenylmethoxycarbonyl (Fmoc) Solid Phase Peptide Synthesis at 60 °C under nitrogen bubbling as previously reported.13Branching points consisted of Fmoc-Lys(Fmoc)-OH to obtained two free amines after Fmoc deprotection (mainchain and sidechain).Synthesis

[0260] 400 mg of resin (Rink amide, 0.29 mmol / g for Dendril, and Ala-Wang, 0.32 mmol / g for Dendri4) was first swollen 10 min in DMF. Double deprotections of Fmoc groups were performed using a solution of 20% v / v piperidine in DMF, during one and four minutes. Resinwas washed five times (5 x 8 mL of DMF) after deprotection. Double coupling (2 x 8min) for the two first generations GO and G1 , quadruple coupling (4 x 8 min) for second generation G2 and septuple coupling (7 x 8 min) for third generation G3 were performed using 3 mL amino acid (0.2 M), 2 mL of DIG (0.8 M) and 1.5 mL Oxyma (0.8 M) in DMF for each coupling. Resin was washed twice with 8 mL of DMF between couplings and three times after the last one. All Fmoc deprotections were performed as described above. After last Fmoc deprotection, resin was washed three times with DMF and three times with MeOH at room temperature.Cleavage

[0261] Peptide was then cleaved from the resin using a 7 mL mixture of TFA / TIS / DODT / H2O (94 / 2.5 / 2.5 / 1 , v / v / v / v) for Dendril and TFA / TIS / H2O (94 / 5 / 1 , v / v / v) for Dendri4. Peptide solutions were then precipitated with 25 mL cold terbutylmethyl ether, centrifuged for 10 minutes at 3500 rpm, evaporated and dried with argon before purification.Purification

[0262] The dried crudes were dissolved in a water / MeCN mixture, filtered (pore size 0.22 pm) and purified by preparative RP-HPLC with gradient of 60 min from 100% solvent A to 100% solvent D described above. Collected fractions were analysed by analytical LC-MS. Peptides were obtained as foamy white solids after lyophilisation. Yields were calculated for the TFA salts.Quantification of Dendrimers

[0263] The resulting dendrimers were quantified as outlined above, using Analytical RP- HPLC combined with LC-MS.Methods - Liposome PreparationSynthesis

[0264] Liposomes containing 25 mol% DSPG and varying amounts of DPPC / cholesterol were produced using the thin-film hydration technique. The lipid stock solutions in a chloroform / MeOH mixture (75 / 25 v / v) were appropriately measured and dried under a mild nitrogen flow in a glass vial, followed by the removal of residual solvents through overnight incubation under vacuum in a desiccator. The lipids were hydrated with 20 mM HEPES buffer at pH 7.4, heated to 70 °C, and mixed to produce vesicles of 20 mM final lipid concentration. These vesicles were then subjected to six freeze-thaw cycles and extruded ten times via a 200 nm polycarbonate membrane (Sterlitech® Corporation, USA) using a LIPEX® extruder at 70 °C (Evonik®, Canada).Characterisation

[0265] The resulting liposomes were characterised as outlined above. Briefly, the mean hydrodynamic diameter and polydispersity in DendriX (PDI) of the formed vesicles were determined via dynamic light scattering (DLS), using a Litesizer 500 instrument (Anton Paar®, Austria) with a backscatter angle of 175° and a 658 nm laser at 25 °C. Furthermore, the zeta potential was measured using the same device and Omega cuvette (Anton Paar®, Austria) with laser Doppler microelectrophoresis.Methods - In vivo InvestigationCell culture

[0266] Synovial fibroblasts (SFs) were obtained from four OA patients and plated onto 25 cm2flasks and 6-well clear Corning® plates (USA) or 96-well black plates with clear bottoms from Thermo Fisher Scientific™ (USA). The cells were maintained at 37 °C in a 5% CO2- enriched humid atmosphere using Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% fetal calf serum (FCS), 50 U / mL penicillin / streptomycin, 2 mM L- glutamine, 10 mM HEPES, and 0.2% amphotericin B (all from Thermo Fisher Scientific™, USA) as per standard protocols.14Once confluent, the OASFs were utilised for experiments between passages 4 and 6. Meanwhile, mouse monocyte macrophages (RAW264.7), which are semiadherent, were grown in the incubator under the same conditions as OASFs. DMEM (4.5 g L'1glucose and phenol red) was added with 1% v / v penicillin / streptomycin mixture, 1% v / v L-glutamine (200 nM), and added 10% v / v FCS, as previously reported.15Once 70-80% confluence was achieved, the cells were harvested using a cell scraper and employed for additional subcultivation.Toxicity of Dendrimers

[0267] The OASFs were quantified using Countess™ 3 FL (Thermo Fisher Scientific™, USA) and trypan blue, and then seeded at a density of 5000 cells per well onto a 96-well plate. After overnight incubation, the cells were subjected to 200 pL of various conditions and incubated for 48 h. Following the incubation, cell viability was determined using the Cell Counting Kit-8 (CCK-8) according to the manufacturer’s (Merck®, Germany) instructions. Briefly, medium was aspirated, and the cells were washed with DPBS (Thermo Fisher Scientific™, USA) before being stained with 100 pL of 10x diluted CCK-8 in medium. Cells were incubated for 2 h at 37 °C and subsequently, the absorbance was measured at 450 nm using a plate reader (BioTek Instruments®, USA).Gene ExpressionFor gene expression studies, the cells were seeded as previously described for the toxicity experiments. To stimulate a fibrotic response, 10 ng / mL of TGFp was added to the mediumalong with the test conditions. After 48 h incubation, the cells were lysed and RNA was extracted using the Quick-RNA™ Microprep Kit (Zymo Research®, USA) and on-column DNase I digestion according to the manufacturer’s instructions. The purity and quantity of RNA were evaluated by measuring the OD ratio at 260 and 280 nm using Nanodrop (Thermo Fisher Scientific™). Subsequently, the RNA was reverse-transcribed, and SYBR®green realtime PCR was conducted (primers: aSMA Fwd: 5' GAC AAT GGC TCT GGG CTC TGT AA 3' (SEQ ID NO: 59), Rev: 5'ATG CCA TGT TCT ATC GGG TAC TT 3' (SEQ ID NO: 60); Col1A1 Fwd: 5' CAG CCG CTT CAC CTA CAG C 3' (SEQ ID NO: 61), Rev: 5' TTT TGT ATT CAA TCA CTG TCT TGC C 3' (SEQ ID NO: 62); Col3A1 Fwd: 5' GGA CCT CCT GGT GCT ATA GGT 3' (SEQ ID NO: 63), Rev: 5' CGG GTC TAC CTG ATT CTC CAT 3' (SEQ ID NO: 64)). Data were analysed with the comparative CT methods and presented as 2-AACT (i.e., x-fold) as described previously16using RPLPO as a housekeeping gene for sample normalisation (Fwd: 5'-GCG TCC TCG TGG AAGTGA CAT CG 3' (SEQ ID NO: 65), Rev: 5'-TCA GGG ATT GCC ACG CAG GG 3' (SEQ ID NO: 66)).Table 2 - Table of primers.Uptake of Aggregated Liposomes and Liposomes

[0268] RAW264.7 cells (2.4 million) were initially cultured in T25 flasks and left to incubate overnight. On the following day, the cell medium was removed, and the cells were washed with PBS. They were then incubated for 3 h with freshly prepared and fluorescently labelled DiD-liposomes, serving as a positive control, and with DiD-aggregated liposomes (such as DiD-Denri4ALs). As a negative control, DMEM was used. The samples were prepared in a phenol red-free medium with reduced FCS content (2 v / v%), following a previously reported protocol.17After incubation, the cells were washed twice with PBS and collected using a cell scraper. Subsequently, the cells were centrifuged for 3 min at 500 g and resuspended in 150 pL buffer at 4 °C containing 0.02% EDTA, 2% v / v FCS, 1% v / v L-glutamine (200 nM), and 1mM pyruvate. The resuspended cells were stored on ice until analysis with flow cytometry, as discussed above.Cartilage Retention

[0269] Porcine cartilage explants were cut in 0.5x0.5 cm pieces, washed with PBS and placed in 12-well microtiter plates. Next, the samples were submerged in 1.5 mL 20 mM HEPES, DendrilAL (50 mg / mL Dendril), Dendri4AL (50 mg / mL Dendri4), and liposome solutions containing equivalent concentrations as in DendriXALs. All liposomal preparations were labelled with 0.05 mol% lipophilic DiD dye. Following a 24 h incubation at 37 °C, the samples were washed with 1.5 mL of PBS. The cartilage surface was analysed with fluorescent stereo microscope imaging, as discussed above.Evaluation of LD50

[0270] Cell culture: Raw264.7 cells were cultivated in Dulbecco’s modified Eagle’s medium (DMEM, high glucose) (11965084; Gibco) complemented with 10 % fetal calf serum (FCS) (F7524-500ML; Sigma Aldrich), Penicillin 100 U / rnL and streptomycin 0.1 mg / mL (15140122; Gibco). Cells were passaged in their exponential phase at 70 - 90 % confluency using cell scrapers and were all in passage 9 - 19. Complex toxicity was performed in 3 biological replicates in triplicates. Specific LD50 values of complexation agents were performed in triplicates.

[0271] Evaluation ofLD50: Cells were seeded in 96-Well plates (5000 cells / well in 100 pL medium) the day before treatment and left overnight for adherence. The cells were then either treated with decreasing doses of the compounds in DMEM (without phenol red, 2 % FBS) using serial dilutions (stock solution 2 mM in Hepes buffer) starting from 200 pg / mL to 1.5 pg / mL for compounds and 10 mM to 1.2 nM for Zn2+or at set concentrations of the liposomes at 5 mM to 0.1 mM with subsequent adjustment of the complexing compound. After 24 h of incubation, the media was removed, the cells washed with PBS once and 100 pL of a 10 % AlamarBlue solution in DMEM (without phenol red, 2% FBS) was added to the wells and the plates were incubated for 2.5 h. The plates were evaluated using a plate reader (Molecular Devices SpectraMax i3x) using the fluorescence at 590 nm and the excitation at 545 nM. The results were then normalised to the fluorescence of the vehicle to determine the percentage of viable cells. These results were then further evaluated in Prism when necessary to determine the LD50 of the compounds.Example 1 - Dendrimer-Aggregated Liposomes (DendriXAL) preparation and characterisation

[0272] Aggregated liposomes (ALs) were generated by four-fold dilution of 0.4 mM liposomes with dendrimer solutions (DendriXs - Dendril and Dendri4) of varying concentrations in 20 mM HEPES followed by gentle stirring for 5 min. The resultant DendriXALs were evaluated using a plate reader, as per previous reports.10Briefly, 50 pL of liposomes, with an initial lipid concentration of 0.4 mM, were combined with 150 pL of differing concentrations of DendriXs in a 96-well microtiter plate with a clear and flat quartz bottom (Hellma® GmbH & Co. KG, Germany). The mixture was gently stirred for 5 min, and the optical density was assessed at 450 nm using an Infinite M Pro 200F-PlexNano microplate reader (Tecan®, Switzerland). Zeta potential of DendriXALs was measured in the same manner as for liposomes using the Litesizer® 500. For the aggregation process involving salts, DendriXs were combined with varying concentrations of NaCI, following which DendriXALs were prepared using the same method as previously mentioned, and subsequently, the optical density was measured as described earlier.

[0273] To investigate if the aggregation process induces a burst release of the encapsulated model drug, rapamycin was incorporated into the liposomes at a lipid-to-drug ratio of 30:1 , following the previously described method.9The in vitro release profile was assessed over a seven-day period using a custom dialysis device and a solution of 10% ethanol in ultrapure water. This method ensured the drug's stability and maintained sink conditions without affecting the liposome composition.Example 2 - Analysis of Polycationic Aggregating Agent

[0274] The peptide dendrimers, Dendril and Dendri4 (DendriXs), were analysed in an aggregation study by measuring changes in optical density and zeta potential at different charge ratios. To calculate these charge ratios, the liposomal surface area based on the average diameter was first determined, and then the number of phospholipid headgroups on the surface was estimated by utilising the average surface area of DPPC molecules and weighing it by the proportion of DSPG molecules in the formulation (i.e. 25 mol%). The following equation was used to calculate the charge ratio in Figure 1 :(where N = number).

[0275] Although the number of positive charges on Dendril and Dendri4 molecules differs, with 12 for the former and 17 for the latter, the aggregation profiles depicted in Figure 1 are similar. A sharp increase in optical density is observed at a charge ratio of 1 , which correlates well with the zeta potential crossing the x-axis. This correlation has also been observed withdivalent cations in previous studies.9 10The observed behaviour can be readily explained by the diminishing repulsive forces between colloidal particles as the negative charges on anionic liposomes are neutralized by the increasing presence of positively charged dendrimers, until the overall charge reaches zero and the system becomes unstable. The subsequent decline in optical density following the aggregation peak is likely due to the increasing charge leading to the formation of water-soluble "dendriosomes," a phenomenon previously observed in the case of poly(amidoamine) (PAMAM) dendrimers and anionic liposomes.18Aggregation in the presence of salt is presented in Figure 2, where the results indicate that the most pronounced aggregation occurs at physiological concentrations of NaCI. Conversely, elevated salt concentrations beyond 150 mM NaCI resulted in diminished aggregation.

[0276] Subsequently, the DendriXs were evaluated in an in vitro fibrosis model using human OASFs. The results depicted in Figure 3 reveal that both DendriXs significantly reduced the expression of the gene for alpha smooth muscle actin (aSMA), while the decrease of collagen type I (Col1A1) expression was significant only for Dendri4.

[0277] To evaluate the toxicity of DenriXs and DendriXALs, OASFs were incubated with both DendriXs and DendriXALs, containing 50 pg / mL of DendriXs and corresponding concentrations of liposomes, for 48 h. Subsequently, cell viability was assessed using the CCK8 kit.

[0278] Results in Figure 4 show that no significant toxicity was induced in the tested conditions with the lowest viability observed in Dendri4AL containing 50 pg / mL Dendri4. Collectively, these findings highlight that DendriXs are effective aggregating agents capable of attenuating the expression of fibrotic markers in human OASFs, as well as the previously reported inflammatory response in monocytes, both of which are pertinent to the treatment of pathologies such as OA. Furthermore, the low toxicity of this system unlocks the previously constrained potential of aggregated liposomes for osteoarthritis treatment.Example 3 - Visualisation of DendriXALs

[0279] The aggregates were imaged with cryoTEM and representative images are displayed in Figure 5. The images display liposomes as mainly unilamellar and nanosized, consistent with DLS data. Upon addition of DendriXs into the system, clear aggregation is observed with membranes tightly packed together and bound by DendriXs. This is evident from the minimal distance between the occasionally curved membranes, which corresponds to the size of the DendriX, particularly noticeable in the DendrilAL images. No discernible penetration of DendriXs into the liposomal core was observed, which might otherwise induce a burst release of the encapsulated cargo. It was indeed confirmed through an in vitro release study of rapamycin encapsulated in liposomes at a 30:1 lipid-to-drug molar ratio. Figure 6 shows thatthere is no variation in the release between plain liposomes, DendrilALs, and Dendri4ALs. Dendrimers' interactions with phospholipid bilayers have been thoroughly investigated, revealing that dendrimer generation plays a significant role and that higher generation dendrimers tend to perturb the membrane more extensively than their lower generation counterparts. Since both Dendril and Dendri4 are G3 dendrimers, their impact on the surface is limited, further corroborating the findings from the cryoTEM images and rapamycin release study.

[0280] To further elucidate the system's morphology on a macroscopic level, DendriXALs were imaged using fluorescence microscopy. The images presented in Figure 7 depict complex morphological features and micrometre-sized structures. This evidence suggests that while employing a different aggregating agent reduces toxicity and imparts both anti-fibrotic and anti-inflammatory properties to the drug delivery system, the overall structure of the dosage form remains largely unaltered. The absence of toxicity also eliminates the need for purification after aggregation. This simplification of the preparation process subsequently reduces the associated costs and complexity.Example 4 - Cartilage Lubrication

[0281] Synovial fibroblast activation, closely associated with pro-inflammatory and pro- fibrotic factors, is strongly correlated with the presence of cartilage wear particles generated during cartilage erosion.1This process is further exacerbated by the increased roughness of the cartilage surface in OA, resulting in higher friction and mechanical wear. Natural biolubricants, which prevent cartilage wear in healthy joints by providing effective lubrication, are diminished in OA, impairing synovial fluid lubrication and leading to increased friction and cartilage degradation.3While small liposomes initially demonstrated promise in reducing friction in vitro, their small size led to suboptimal performance compared to larger particles in ex vivo studies.8It was recently reported that liposomal aggregates could protect cartilage from friction induced by the aggregating agent and form a protective layer on ex vivo porcine cartilage. However, the coefficient of friction (COF) was not significantly reduced compared to that observed with liposomes.

[0282] To determine whether DendriXALs are more efficient in reducing COF, we tested their macro-tribological effect on the same ex vivo porcine model, with results illustrated in Figure 8. The results indicate that DendrilAL performed better (COF = 0.02) than plain liposomes (COF = 0.08) in reducing COF and successfully protected the cartilage from the negative impact of free Dendril (COF = 0.12) on the cartilage surface. Similar observations were made for Dendri4ALs, which reduced friction more effectively than all other controls. The increased friction in DendriXs is likely due to the strong electrostatic interaction between thehighly cationic peptides and the negatively charged cartilage surface, which could damage the surface. Liposomes in the DendriXAL system sequester the cations and bind them tightly to the surface, preventing surface deformation. It is theorised that the liposomal lubricating effect is due to the formation of a hydration shell at the phospholipid headgroup region, which is highly pressure-resistant and capable of reducing friction. In the case of DendriXAL, it is hypothesised that the large particles observed in Figure 7 form an extensive protective layer on the cartilage surface, preventing excessive friction or wear on the tissue's surface.Example 5 - DendriXAL retention on cartilage

[0283] An important aspect of cartilage lubrication and protection from wear is the retention on the cartilage surface, as the material can only lubricate if it is present at the interface. Small nanosized particles are known to undergo quick clearance from the joint through the lymphatic drainage system and phagocytosis.56To increase the residence time in the joint, researchers developed cartilage targeting systems, which are often designed to penetrate the cartilage pores2and don’t necessarily offer the lubricating effect, as they are not sufficiently retained at the surface.8To test whether the DendriXALs increase the retention on the cartilage surface, porcine cartilage was cut, placed in 12-well plates, and incubated for 24 h with buffer, DiD- labelled plain liposomes, and DendriXALs. Figure 9A reports the comparison of intensity measurements for liposomes and DendriXALs, while Figure 9B and 9C show the treated cartilage surface with DendrilAI and Dendri4AL, respectively, under 50X magnification. While there was no difference between the retention of the plain liposomes and DendrilALs, significantly higher retention was observed in the case of Dendri4ALs. The observed increase in retention for Dendri4ALs can be attributed to the ~2 kDa greater molecular weight and increased number of positive charges of the Dendri4 dendrimer (9.4 kDa and 17 positive charges) relative to the Dendril dendrimer (7.4 kDa and 12 positive charges). This disparity in molecular weight and charge density may foster more robust interactions between the Dendri4ALs and the cartilage surface, ultimately leading to improved retention. This enhanced interaction could be the result of a heightened electrostatic attraction between the Dendri4 dendrimer and the anionic liposomes, as well as the negatively charged cartilage surface. Moreover, the larger size of the Dendri4 dendrimer could also play a role in the increased retention via steric effects, thereby promoting a more stable association with the cartilage surface. These results offer an explanation of the better performance of Dendri4ALs in the lubrication study in Figure 8, where the COF was reduced significantly compared to plain liposomes. However, the lack of increased retention of DendrilALs is interesting, as this system also reduced friction beyond free liposomes. The possible explanation for this result is that the increased retention on the surface is not the only mechanism for the lubrication of the system. Indeed, during the macro-tribological measurements, the cartilage was incubated withDendriXALs and was not exposed to any washing step, which kept the aggregates on the surface of the cartilage.Example 6 - Cellular Uptake on Dendri4ALs

[0284] Building on the key role of particle size and retention within the joint space, it is essential to address the cellular uptake by immune cells as a pivotal consideration in the formulation of a proficient drug delivery system. The rate of uptake by these immune cells can significantly dictate the therapeutic efficacy of the delivered drugs by impacting their clearance. In the context of liposomes, despite their documented effectiveness in amplifying drug retention within the joint space, their relatively small size often predisposes them to expedited clearance.19This rapid removal is mediated primarily by phagocytosis, a biological process which is especially responsive to the size of the vesicles.20Research suggests that particles larger than 10 pm can substantially evade immune cell uptake, thereby enhancing their retention in the target area.56However, particle size is only one factor and the composition of these vesicles plays an equally significant role. Specifically, liposomes containing cationic lipids, though associated with toxicity challenges, exhibit a propensity to form a protein corona. This results in an increased attraction of surrounding proteins to their surface, enhancing the phagocytosis process and consequently, clearance from the joint space. Contrastingly, neutral nanoparticles are found to have a prolonged presence in plasma due to their reduced ability to adsorb proteins.21These aspects - size and composition - are therefore integral to the development of an optimal drug delivery system for OA therapy.

[0285] In order to evaluate this aspect, Dendri4AL was selected for testing uptake into RAW264.7 macrophages. This decision was based on its compelling performance in joint lubrication and its ability to improve cartilage retention. The DiD-labelled system was incubated with cells and compared with a negative DMEM control and a positive liposome control. After a 3-h treatment, the cells were harvested and analysed using Image Stream®, a fluorescent imaging flow cytometer. The results depicted in Figure 10 show a significant reduction in DiD intensity in live cells. These findings are likely associated with the presence of large macroscopic Dendri4AL structures — as shown in Figure 7 — which may sterically hinder phagocytosis. The representative images in Figure 10C show that the uptaken particles are integrated within the cell cytoplasm and distributed around the nucleus. The fact that Dendri4Als are still phagocytosed by the macrophages, albeit to a lower extent, can be explained with the softness of the liposomal material, which was correlated with facilitated cellular uptake.Example 7 - Aggregation Profiles of DPPC:DSPG Liposomes and Polycationic Aggregation Agents

[0286] A larger array of polycationic aggregating agents listed in Table 3 were tested to assess their ability to induce aggregate formation upon interaction with negatively charged liposomes. The experiment involved incubating a fixed concentration of liposomes (1 mM, DSPG:DPPC ratio of 1 :3 mol / mol) with varying concentrations of aggregating agents to achieve desired charge ratios (positively charged to negatively charged). The following equation was used to calculate the charge ratios in Figures 11A and 11 B:N-charges 1 mM and 1 mL of phospholipids=N liposomes measured by NTA X N-charges per liposome(where N = number).

[0287] The mixtures were prepared in 96-well microtiter plates with a clear and flat quartz bottom (Hellma® GmbH & Co. KG, Germany). After gentle stirring for 5 minutes, the optical density of the mixtures was measured at 450 nm using an Infinite M Pro 200F-PlexNano microplate reader (Tecan®, Switzerland). The results in Figure 11A and Figure 11B indicate that all tested polycationic aggregation agents induced aggregation and that the approach was universal among them.Table 3 - Polycationic aggregating agents used in the aggregation study (Example 7) and the macrophage uptake study with RAW264.7 cells (Example 8)Example 8 - Macrophage Uptake Study

[0288] To assess the ability of the liposomes and some of the aggregates described in Example 7 to reduce immune clearance from the joint, a critical factor for intra-articular injections to persist at the injection site, the macrophage uptake experiment was performed using the protocol: “Uptake of Aggregated Liposomes and Liposomes” described in the Methods section above, and an imaging flow cytometer was used for analysis as described in “Flow Cytometry” in the Analytical Methods section above. Aggregates were prepared with Dendril (D1), glatiramer acetate (GA), i-PAMAM, LL-37, Polymyxin B (PMB) and polyarginine (Poly-Arg) (see, Table 3 which lists these polycationic aggregating agents along with their respective + / - charge ratios), and were evaluated for their ability to evade immune clearance.

[0289] The findings from this study are displayed in Figure 12, which demonstrates a decrease in macrophage uptake with the aggregates, when compared to the liposome control. This suggests that combining polycationic aggregating agents with liposomes is an effective strategy to reduce clearance from joints, making them suitable for intra-articular injections.Example 9 - Toxicity study on OA synovial fibroblasts - comparison of aggregated liposomes prepared with: polycationic aggregating agents Dendril and Dendri4; and divalent Zn2+

[0290] In previous studies on the use of aggregated liposomes for intra-articular (IA) injections, formulations have employed divalent aggregating agents, such as zinc (Zn2+). These formulations required large amounts of cations to deliver therapeutic agents like rapamycin (RAPA) in effective concentrations, resulting in high toxicity in relevant cell cultures, including synovial fibroblasts from OA patients. Attempts to reduce this toxicity through dialysis of excess Zn2+(the proposed composition for IA administration had 150 mM Zn2+per 5 mM liposomes before dialysis, which was required) were inadequate, as the resultant formulations still exhibited significant toxicity. Therefore, new aggregating agents are crucial for the successful application of liposomal aggregates in IA injections.9

[0291] The toxicity of RAPA-loaded aggregated liposomes (ZnAL, Denril AL and Dendri4AL) was determined using the method: “Toxicity of Dendrimers” described above. However, cellviability was determined using either the *Cell Counting Kit-8 (CCK-8, Merck®, Germany) or the **LIVE / DEAD™ viability kit (Thermo Fisher Scientific, USA) according to the manufacturer’s instructions, as shown in Figure 13. Figure 13 demonstrates that higher doses of RAPA can be delivered using multivalent cations (e.g., Dendril with 12+ charges and Dendri4 with 17+ charges) without inducing significant toxicity, compared to free liposome controls. The rationale is that multivalent cations aggregate liposomes more efficiently than divalent cations, requiring fewer molecules for aggregation and maintaining a favorable LD50. This results in lower overall cation concentrations and reduced toxicity, as depicted in Table 4. This substitution simplifies preparation and enhances the clinical translatability of the formulation, as no further processing is needed after aggregation, unlike with Zn2+aggregates.Table 4 - Composition ofZnALs, Dendril ALs, and Dendri4ALs at highest viable RAPA doseExample 10 - Toxicity study on immune cell lineDirect comparison of aggregated liposomes prepared with: polycationic aggregating agents: LL-37, Dendril and Dendri4; and divalent Zn2+

[0292] To further demonstrate the improved biocompatibility of the compositions of the invention, a direct cytotoxicity study was performed comparing i) aggregated liposomes prepared with several polycationic aggregating agents (Dendril (D1), Dendri 4 (D4), and LL- 37) with ii) divalent Zn2+ aggregates on RAW264.7 macrophages (Figure 14). Macrophages are crucial in osteoarthritis (OA) due to their significant impact on joint inflammation and material clearance from the synovium. The aggregates were composed of liposomes (DPPC:DSPG = 3:1 molar ratio) with standard concentrations and the necessary amounts of aggregating agents (see, Table 5). Zn2+aggregates were prepared following the protocol described in Bordon et al.9

[0293] The results from this study indicate that Zn2+aggregated liposomes are highly cytotoxic, killing nearly all cells at the minimal liposome concentration (0.1 mM). In contrast, aggregated liposomes prepared with the polycationic aggregating agents: Dendril (D1), Dendri 4 (D4), and LL-37, showed no cytotoxicity at the same concentration. These findings corroborate previous results obtained with OASFs and highlight the significant advantage of using polycationic aggregating agents over divalent Zn2+for forming liposomal aggregates for IA injections.

[0294] Table 5 presents the compositions of the aggregates used in this study, necessary to form stable aggregates. The composition of Zn2+required significantly higher molar concentrations of the aggregating agent compared to the polycationic agents (D1 , D4, and LL- 37). This reinforces the need for more molecules to achieve liposome aggregation with Zn2+than with polyvalent cations.Table 5 - Composition of aggregates ata 0.5 mM liposome concentration. Compositions were selected based on the aggregation profiles for the polycationic aggregation agents used and the reported optimal concentration for divalent Zn2+aggregates, where ZnC was used for aggregate formation, as described by Bordon et al.9Evaluation of LD50

[0295] Table 6 below demonstrates the comparative toxicities of ZnCh (Zn2+) and a series of polycationic aggregating agents on a macrophage cell line. The LD50 of ZnCh is 5.87 pg / mL, which is lower than the LD50 for the other polycationic aggregating agents tested, suggesting higher cytotoxicity. The study was conducted according to the method: “Evaluation of LD50” described above.Table 6 - LD50 values of different aggregating agents. All concentrations are given in / jg / mL.ADDITIONAL EMBODIMENTSThe invention is further illustrated by the following numbered embodiments:1. A composition for use in the treatment of a joint disease or disorder, wherein the composition comprises an anionic lipid composition; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.2. The composition for use according to clause 1, wherein the composition further comprises a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is incorporated into the anionic lipid composition.3. The composition for use according to clause 1 or clause 2, wherein the anionic lipid composition comprises liposomes, lipid nanoparticles, solid lipid nanoparticles, and nanostructured lipid carriers.4. The composition for use according to clause 3, wherein the anionic lipid composition comprises liposomes.5. The composition for use according to clause 4, wherein the liposomes comprise negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn-g / ycero-3- phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1,2-distearoyl-sn-g / ycero- 3-phospho-(1'-rac-glycerol) (DSPG), 1,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1,2- dipalmitoyl-sn-glycero-3-phospho-(1-rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn-glycero-3- phospho-(l-rac-glycerol) (DOPG), 1,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn-glycero-3- phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero-3- phospho-(1 '-myo-inositol) (DOPI), or 1,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol-3'- 4'-5'-triphosphate) (DOPI-P3), or combinations thereof.6. The composition for use according to clause 5, wherein the liposomes further comprise one or more neutral or zwitterionic lipid, for example cholesterol, or a phosphocholine lipid (e.g. 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-distearoyl-sn-glycero-3- phosphocholine (DSPG)), or combinations thereof.7. The composition for use according to any one of clauses 1 to 6, wherein the polycationic aggregation agent comprises 2 or more separate positively charged sites at a pH range of between 6.0 and 8.0.8. The composition for use according to clause 7, wherein the polycationic aggregation agent is a pharmaceutically active agent, optionally wherein the polycationic aggregation agent is a polycationic anti-inflammatory agent or a polycationic anti-fibrotic agent.9. The composition for use according to clause 8, wherein the polycationic aggregation agent is an anti-inflammatory agent comprising an amino acid selected from the group consisting of lysine, alanine, glutamic acid, and tyrosine, or combinations thereof, optionally wherein the anti-inflammatory agent comprises a polymer comprising 40 to 100 amino acid polymer comprising four amino acids selected from L-alanine, L-lysine, L-glutamic acid, and L-tyrosine, for example where the anti-inflammatory agent is glatiramer or a pharmaceutically acceptable salt thereof.10. The composition for use according to clause 8, wherein the anti-inflammatory agent is selected glatiramer acetate.11. The composition for use according to clause 8, wherein the polycationic aggregation agent is a polycationic anti-fibrotic agent.12. The composition for use according to clause 7, wherein the polycationic aggregation agent comprises chitosan, poly(dimethyldiallylammonium chloride), polyamine, polyallylamine, polyethyleneimine, poly(dimethylaminoethyl acrylate), polylysine, polyhistidine, polyornithine, polyarginine, polyquats (starch derivatives with amino or ammonium groups), or combinations thereof.13. The composition for use according to clause 7, wherein the polycationic aggregation agent is a polycationic dendrimer.14. The composition for use according to clause 13, wherein the dendrimer is a poly(amidoamine) (PAMAM) dendrimer, a polypropylene imine) (PPI) dendrimer, a triazine dendrimer, a phosphorus dendrimer, or a peptide dendrimer.15. The composition for use according to clause 13 or clause 14, wherein the dendrimer is a G2 or G3 dendrimer, preferably wherein the dendrimer is a G3 dendrimer.16. The composition for use according to any one of clauses 13 to 15, wherein the dendrimer comprises an amino acid selected from the group consisting of lysine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof.17. The composition for use according to any one of clauses 13 to 16, wherein the dendrimer comprises one of the following linear notations: (KA)s(KAK)4(KEKA)2KAKEAYCA- NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).18. The composition for use according to any one of clauses 2 to 17, wherein the pharmaceutically active agent is selected from the group consisting of anti-inflammatory agents, anti-fibrotic agents, anti-microbial agents, non-steroidal anti-inflammatory agents, corticosteroids and biological agents (e.g. peptides, proteins, stem cells, antibodies and antibody fragments).19. The composition for use according to any one of clauses 2 to 18, wherein the pharmaceutically active agent is selected from the group consisting of triamcinolone, prednisone, hydrocortisone, methylprednisolone, dexamethasone, betamethasone, hyaluronic acid, certolizumab pegol, golimumab, belimumab, rituximab, rapamycin, torin-1 , torin-2, retinoic acid metabolism blocking agents (e.g. talarazole, liarozole), naproxen, ibuprofen, diclofenac, celecoxib, meloxicam, lornoxicam, kartogenin, dasatinib, quercetin, rhein, sinomenine, liquiritin, glatiramer acetate, insulin-like growth factor 1 (IGF 1), Resolvin D1 , fibroblast growth factor 18 (FGF 18), bone morphogenetic protein (BMP) 7, an anti-IL-1 agent (e.g. canakinumab, anakinra, ilonacept, gevokizumab), an anti-TNF agent (e.g. infliximab, adalimumab, etanercept), Botulinum toxin A, a JAK inhibitor (e.g. tofacitinib, filgotinib, upadacitinib, TD-1473, Brepocitinib (PF-06700841), PF-06651600), pirfenidone, or nintedanib, cathelicidin, LL-37, polymyxin B, magainin, murepavadin, MK-8722, or combinations thereof.20. The composition for use according to any one of clauses 1 to 19, wherein the joint disease or disorder is selected from arthritis, osteoarthritis, arthrofibrosis, rheumatoid arthritis, gout, bursitis, bacterial arthritis, juvenile idiopathic arthritis, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, tendinopathy, polymyalgia rheumatica, Paget’s disease, lupus, Sjogren’s Syndrome, osteonecrosis, neuropathic arthropathy, or Lyme disease.21 . The composition for use according to clause 20, wherein the joint disease or disorder is osteoarthritis.22. The composition for use according to any one of clauses 1 to 21 , wherein composition comprises aggregates comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent.23. The composition for use according to any one of clauses 1 to 22, wherein the composition forms a sustained release depot following intraarticular administration to a subject.24. A composition comprising:• an anionic liposome; and• a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)s(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).25. The composition according to clause 24, further comprising a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is encapsulated in the anionic liposome.26. The composition according to clause 24 or clause 25, wherein the anionic liposome comprises negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn- g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1 ,2-distearoyl- sn-g / ycero-3-phospho-(T -rac-glycerol) (DSPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 -rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn- glycero-3-phospho-(1 -rac-glycerol) (DOPG), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn- glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero- 3-phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol- 3'-4'-5'-triphosphate) (DOPI-P3), or combinations thereof.27. The composition according to clause 26, wherein the anionic liposome further comprises one or more neutral or zwitterionic lipid, for example, cholesterol, or a phosphocholine lipid (e.g. 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1 ,2- distearoyl-sn-glycero-3-phosphocholine (DSPG)), or combinations thereof.28. The composition according to any one of clauses 24 to 27, wherein the composition comprises aggregates comprising the cationic dendrimer aggregation agent and a plurality of the anionic liposomes.29. A kit comprising:a) a first container comprising an anionic lipid composition; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use according to any one of clauses 1 to 23.30. The kit according to clause 29, wherein the first container further comprises a pharmaceutically active agent incorporated into the anionic lipid composition.FURTHER EMBODIMENTSThe invention is also illustrated by the following numbered embodiments:P1. A composition for use in the treatment of a joint disease or disorder, wherein the composition comprises an anionic lipid composition; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.P2. The composition for use according to P1, wherein the composition further comprises a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is incorporated into the anionic lipid composition.P3. The composition for use according to P1 or P2, wherein the anionic lipid composition comprises liposomes, lipid nanoparticles, solid lipid nanoparticles, and nanostructured lipid carriers.P4. The composition for use according to P3, wherein the anionic lipid composition comprises liposomes.P5. The composition for use according to P4, wherein the liposomes comprise negatively charged lipids selected from the group consisting of 1,2- dipalmitoyl-sn-g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1,2-distearoyl-sn-g / ycero-3-phospho- (T-rac-glycerol) (DSPG), 1,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl- sn-glycero-3-phospho-(1-rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1-rac- glycerol) (DOPG), 1,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1,2-dipalmitoyl-sn- glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo- inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DOPI), or 1,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DOPI- P3), or combinations thereof.P6. The composition for use according to P5, wherein the liposomes further comprise one or more neutral or zwitterionic lipid, for example cholesterol, or a phosphocholine lipid (e.g. 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1 ,2-distearoyl-sn-glycero-3- phosphocholine (DSPC)), or combinations thereof.P7. The composition for use according to any one of P1 to P6, wherein the polycationic aggregation agent comprises 2 or more separate positively charged sites at a pH range of between 6.0 and 8.0.P8. The composition for use according to P7, wherein the polycationic aggregation agent is a pharmaceutically active agent, optionally wherein the polycationic aggregation agent is a polycationic anti-inflammatory agent, a polycationic anti-microbial agent or a polycationic anti- fibrotic agent.P9. The composition for use according to P8, wherein the polycationic aggregation agent is an anti-inflammatory agent comprising an amino acid selected from the group consisting of lysine, alanine, glutamic acid, and tyrosine, or combinations thereof, optionally wherein the anti-inflammatory agent comprises a polymer comprising 40 to 100 amino acid polymer comprising four amino acids selected from L-alanine, L-lysine, L-glutamic acid, and L-tyrosine, for example where the anti-inflammatory agent is glatiramer or a pharmaceutically acceptable salt thereof.P10. The composition for use according to P8, wherein the anti-inflammatory agent is glatiramer acetate.P11. The composition for use according to P8, wherein the polycationic aggregation agent is a polycationic anti-fibrotic agent.P12. The composition for use according to P7, wherein the polycationic aggregation agent comprises a polyamine.P13. The composition for use according to P12, wherein the polyamine comprises a peptide or a polypeptide.P14. The composition for use according to P13, wherein the peptide or the polypeptide comprises at least 2, at least 3, at least 4, at least 5 or at least 6 different amino acids.P15. The composition for use according to P13, wherein the peptide or the polypeptide comprises polylysine, polyhistidine, polyornithine or polyarginine.P16. The composition for use according to P12, wherein the polyamine comprises one or more amino sugar residues.P17. The composition for use according to P16, wherein the polymer comprising one or more amino sugar residues is a polymer, optionally wherein the polymer is chitosan or chitin.P18. The composition for use according to P16, wherein the polyamine comprises an aminoglycoside.P19. The composition for use according to any one of P12 to P17, wherein the polyamine comprises chitosan, chitin, an aminoglycoside, poly(dimethyldiallylammonium chloride), poly(amidoamine) (PAM AM), inverse poly(amidoamine) (i-PAMAM), polypropylene imine) (PPI), a triazine-based polymer, polyallylamine, polyethyleneimine, poly(dimethylaminoethyl acrylate), a peptide or a polypeptide (e.g. polylysine, polyhistidine, polyornithine, polyarginine), a polyquaternium, or any combination thereof.P20. The composition for use according to P18, wherein the aminoglycoside is selected from streptomycin, gentamicin, tobramycin, amikacin, dibekacin, sisomicin, netilmicin, neomycin (e.g. neomycin B, neomycin C or neomycin E), plazomicin, spectinomycin, kanamycin, tobramycin, apramycin, hygromycin B, fortimicin, and combinations thereof.P21. The composition for use according to any one of P12 to P19, wherein the polyamine is branched.P22. The composition for use according to P7, wherein the polycationic aggregation agent is a polycationic dendrimer.P23. The composition for use according to P13, wherein the dendrimer is a poly(amidoamine) (PAMAM) dendrimer, an inverse poly(amidoamine) (i-PAMAM) dendrimer, a polypropylene imine) (PPI) dendrimer, a triazine dendrimer, a phosphorus dendrimer, or a peptide dendrimer.P24. The composition for use according to P13 or P14, wherein the dendrimer is a G2 or G3 dendrimer, preferably wherein the dendrimer is a G3 dendrimer.P25. The composition for use according to any one of P13 to P15, wherein the dendrimer comprises an amino acid selected from the group consisting of lysine, leucine, arginine, asparagine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof, optionally wherein the dendrimer comprises an amino acid selected from the group consisting of lysine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof.P26. The composition for use according to P25, wherein the dendrimer is described by a general formula (A)s-(B)4-(C)2-Z, wherein:A is XIAX2X3;B is X1BX4X5X6X7;C is XiBXsXsXyXeXy; and wherein:X is selected from lysine, and arginine;XIB is lysine;X2 is selected from leucine, norleucine and alanine;X3 is absent or tyrosine;X4 is selected from lysine, arginine and alanine; each X5 is independently selected from lysine, leucine and alanine; each X6is independently absent or lysine; each X7 is independently absent, glutamic acid or alanine;Xs is selected from lysine, tyrosine, leucine, arginine and glutamic acid; andZ is a core moiety.P27. The composition for use according to P26, wherein A is selected from: KL, kl, rl, KA and k{NLE}y (SEQ ID NO: 91).P28. The composition for use according to P26 or P27, wherein B is selected from: KKL, kkl, krl, KAK and KKAKE (SEQ ID NO: 92).P29. The composition for use according to any one of P26 to P28, wherein C is selected from: KKL, kll, krl, KEKA (SEQ ID NO: 93) and KYKAKA (SEQ ID NO: 94).P30. The composition for use according to any one of P26 to P29, wherein Z comprises from 1 to 10 amino acids, optionally wherein Z comprises one or more C2-C30 alkyl groups.P31. The composition for use according to any one of P22 to P30, wherein the dendrimer comprises one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86);(k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90);(KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70);(kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74);(kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or(rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82).P32. The composition for use according to clause P31 , wherein the dendrimer comprises one of the following linear notations: (KA)s(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).P33. The composition for use according to any one of P1 to P7, wherein the polycationic aggregation agent is selected from the group consisting of: inverse poly(amidoamine) (i- PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, Walk11.3, or a (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)s(krl)4(krl)2kk(Cis) (consisting of SEQ ID NO: 79 to 82).P34. The composition for use according to any one of P2 to P33, wherein the pharmaceutically active agent is selected from the group consisting of anti-inflammatory agents, anti-fibrotic agents, anti-microbial agents, non-steroidal anti-inflammatory agents, corticosteroids and biological agents (e.g. peptides, proteins, stem cells, antibodies and antibody fragments).P35. The composition for use according to any one of P2 to P34, wherein the pharmaceutically active agent is selected from the group consisting of triamcinolone, prednisone, hydrocortisone, methylprednisolone, dexamethasone, betamethasone, hyaluronic acid, certolizumab pegol, golimumab, belimumab, rituximab, rapamycin, torin-1 , torin-2, retinoic acid metabolism blocking agents (e.g. talarazole, liarozole), naproxen, ibuprofen, diclofenac, celecoxib, meloxicam, lornoxicam, kartogenin, dasatinib, quercetin, rhein, sinomenine, liquiritin, glatiramer acetate, insulin-like growth factor 1 (IGF 1), Resolvin D1 , fibroblast growth factor 18 (FGF 18), bone morphogenetic protein (BMP) 7, an anti-IL-1 agent (e.g. canakinumab, anakinra, ilonacept, gevokizumab), an anti-TNF agent (e.g. infliximab, adalimumab, etanercept), Botulinum toxin A, a JAK inhibitor (e.g. tofacitinib, filgotinib, upadacitinib, TD-1473, Brepocitinib (PF-06700841), PF-06651600), pirfenidone, or nintedanib, cathelicidin, LL-37, polymyxin B, magainin, murepavadin, MK-8722, or combinations thereof.P36. The composition for use according to any one of P1 to P35, wherein the joint disease or disorder is selected from arthritis, osteoarthritis, arthrofibrosis, rheumatoid arthritis, gout, bursitis, bacterial arthritis, juvenile idiopathic arthritis, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, tendinopathy, polymyalgia rheumatica, Paget’s disease, lupus, Sjogren’s Syndrome, osteonecrosis, neuropathic arthropathy, or Lyme disease.P37. The composition for use according to P36, wherein the joint disease or disorder is osteoarthritis.P38. The composition for use according to any one of P1 to P37, wherein composition comprises aggregates comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent.P39. The composition for use according to any one of P1 to P38, wherein the composition forms a sustained release depot following intraarticular administration to a subject.P40. A composition comprising:• an anionic liposome; and• a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.3.P41. The composition according to P40, wherein the polycationic aggregation agent is a cationic dendrimer aggregation agent comprising one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86);(k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90);(KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70);(kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74);(kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or(rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82).P42. The composition according to P41 , wherein the cationic dendrimer aggregation agent comprises one of the following linear notations (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).P43. The composition according to any one of P40 to P42, further comprising a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is encapsulated in the anionic liposome.P44. The composition according to any one of P40 to P43, wherein the anionic liposome comprises negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn- g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1 ,2-distearoyl- sn-g / ycero-3-phospho-(T -rac-glycerol) (DSPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 -rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn- glycero-3-phospho-(1 -rac-glycerol) (DOPG), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn- glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero- 3-phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol- 3'-4'-5'-triphosphate) (DOPI-P3), or combinations thereof.P45. The composition according to P44, wherein the anionic liposome further comprises one or more neutral or zwitterionic lipid, for example, cholesterol, or a phosphocholine lipid (e.g. 1 ,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1 ,2-distearoyl-sn-glycero-3- phosphocholine (DSPC)), or combinations thereof.P46. The composition according to any one of P40 to P45, wherein the composition comprises aggregates comprising the cationic dendrimer aggregation agent and a plurality of the anionic liposomes.P47. A kit comprising: a) a first container comprising an anionic lipid composition;b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use according to any one of P1 to P39.P48. The kit according to P47, wherein the first container further comprises a pharmaceutically active agent incorporated into the anionic lipid composition.References1. A.M. Silverstein, R.M. Stefani, E. Sobczak, E.L. Tong, M.G. Attur, R.P. Shah, J.C.Bulinski, G.A. Ateshian, C.T. Hung, Toward understanding the role of cartilage particulates in synovial inflammation, Osteoarthr. Cartil. 25 (2017) 1353-1361. htps: / / doi.Org / 10.1016 / J.JQCA.2017.03.015.2. M. Di Francesco, A. Fragassi, M. Pannuzzo, M. Ferreira, S. Brahmachari, P. Decuzzi,Management of osteoarthritis: From drug molecules to nano / micromedicines, Wiley Interdiscip. Rev. Nanomedicine Nanobiotechnology. 14 (2022) e1780. htps: / / doi.org / 10.1002 / WNAN.1780.3. H. Yuan, L.L.E. Mears, Y. Wang, R. Su, W. Qi, Z. He, M. Valtiner, Lubricants for osteoarthritis treatment: From natural to bioinspired and alternative strategies, Adv. Colloid Interface Sci. 311 (2023) 102814. htps: / / doi.2022.102814.4. D.J. Hunter, C.C. Chang, J.C.C. Wei, H.Y. Lin, C. Brown, T.T. Tai, C.F. Wu, W.C.M.Chuang, S.F. Shih, TLC599 in patients with osteoarthritis of the knee: a phase Ila, randomized, placebo-controlled, dose-finding study, Arthritis Res. Ther. 24 (2022) 1-11. htps: / / doi.or S13075-022-02739-4.5. J. Pradal, P. Maudens, C. Gabay, C.A. Seemayer, O. Jordan, E. Allemann, Effect of particle size on the biodistribution of nano- and microparticles following intra-articular injection in mice, Int. J. Pharm. 498 (2016) 119-129. htps: / / doi.Org / 10.1016 / J.IJPHARM.2015.12.015.6. J. A. Champion, A. Walker, S. Mitragotri, Role of particle size in phagocytosis of polymeric microspheres, Pharm. Res. 25 (2008) 1815-1821. https: / / doi.org / 10.1007 / S11095- 008-9562-Y.7. R. Goldberg, J. Klein, Liposomes as lubricants: beyond drug delivery, Chem. Phys. Lipids. 165 (2012) 374-381.8. S. Sivan, A. Schroeder, G. Verberne, Y. Merkher, D. Diminsky, A. Priev, A. Maroudas, G. Halperin, D. Nitzan, I. Etsion, Y. Barenholz, Liposomes act as effective biolubricants for friction reduction in human synovial joints, Langmuir. 26 (2010) 1107-1116. htps: / / doi.org / 10.1021 / LA9Q24712.9. G. Bordon, S.N. Ramakrishna, S.G. Edalat, R. Eugster, A. Arcifa, S. Aleandri, M.F. Bertoncelj, L. Isa, R. Crockett, O. Distler, P. Luciani, Liposomal aggregates sustain the release of rapamycin and protect cartilage from friction, Journal of Colloid and Interface Science, 2023, ISSN 0021-9797, htps: / / doi.Org / 10.1016 / i.icis.2023.07.087.10. L. Rahnfeld, J. Thamm, F. Steiniger, P. van Hoogevest, P. Luciani, Study on the in situ aggregation of liposomes with negatively charged phospholipids for use as injectable depot formulation, Colloids Surfaces B Biointerfaces. 168 (2018) 10-17. htps: / / doi.Org / 10.1016 / j.colsurfb.2018.02.023.11. S. Aleandri, L. Rahnfeld, D. Chatzikleanthous, A. Bergadano, C. Buhr, C. Detotto, S. Fuochi, K. Weber-Wilk, S. Schurch, P. van Hoogevest, P. Luciani, Development and in vivo validation of phospholipid-based depots for the sustained release of bupivacaine, Eur. J. Pharm. Biopharm. 181 (2022) 300-309. htps: / / d0i.0rg / l 0.1016 / j.ejpb.2022.11.019.12. M. Jarosz, M. Olbert, G. Wyszogrodzka, K. Mlyniec, T. Librowski, Antioxidant and antiinflammatory effects of zinc. Zinc-dependent NF-KB signaling, Inflammopharmacology 2017 251. 25 (2017) 11-24. https: / / dob "1017-03113. D. Erzina, A. Capecchi, S. Javor, J.L. Reymond, An Immunomodulatory Peptide Dendrimer Inspired from Glatiramer Acetate, Angew. Chemie Int. Ed. 60 (2021) 26403-26408. htps: / / doi.org / 10.1002 / ANIE.202113562.14. X. Ge, M. Frank-Bertoncelj, K. Klein, A. McGovern, T. Kuret, M. Houtman, B. Burja, R. Micheroli, C. Shi, M. Marks, A. Filer, C.D. Buckley, G. Orozco, O. Distler, A.P. Morris, P. Martin, S. Eyre, C. Ospelt, Functional genomics atlas of synovial fibroblasts defining rheumatoid arthritis heritability, Genome Biol. 22 (2021) 1-39. https: / / doi.Org / 10.1186 / S13059- 021-02460-6.15. F. Weber, D.C. Ivan, S.T. Proulx, G. Locatelli, S. Aleandri, P. Luciani, Beyond Trial and Error: A Systematic Development of Liposomes Targeting Primary Macrophages, Adv. NanoBiomed Res. 1 (2021) 2000098. htps: / / doi.org / 10.1002 / ANBR.202000Q98.16. T.D. Schmittgen, E.J. Lee, J. Jiang, A. Sarkar, L. Yang, T.S. Elton, C. Chen, Real-time PCR quantification of precursor and mature microRNA, Methods. 44 (2008) 31-38. htps: / / doi.Org / 10.1016 / J.YMETH.2007.09.006.17. Y. Song, J. Zhang, H. Xu, Z. Lin, H. Chang, W. Liu, L. Kong, Mesenchymal stem cells in knee osteoarthritis treatment: A systematic review and meta-analysis, J. Orthop. Transl. 24 (2020) 121-130. htps: / / doi.Org / 10.1016 / J. JQT.2020.03.015.18. B. Roy, A.K. Panda, S. Parimi, I. Ametov, T. Barnes, C.A. Prestidge, Physico-chemicalStudies on the Interaction of Dendrimers with Lipid Bilayers. 1. Effect of Dendrimer Generation and Liposome Surface Charge, J. Oleo Sci. 63 (2014) 1185-1193. htps: / / doi.org / 10.5650 / JQS.ESS14081.19. W. Lin, R. Goldberg, J. Klein, Poly-phosphocholination of liposomes leads to highly- extended retention time in mice joints, J. Mater. Chem. B. 10 (2022) 2820-2827. htps: / / doi.Org / 10.1039 / D1TB02346B.20. N. Onishchenko, D. Tretiakova, E. Vodovozova, Spotlight on the protein corona of liposomes, Acta Biomater. 134 (2021) 57-78. htps: / / doi.Org / 10.1016 / J.ACTBIO.21. S.C. Semple, A. Chonn, P.R. Cullis, Interactions of liposomes and lipid-based carrier systems with blood proteins: Relation to clearance behaviour in vivo, Adv. Drug Deliv. Rev. 32 (1998) 3-17. htps: / / doi.org / 10.1016 / S0K * ' K(97)00128-2.

Claims

CLAIMS1. A composition for use in the treatment of a joint disease or disorder, wherein the composition comprises an anionic lipid composition; and a polycationic aggregation agent, wherein the composition is administered intraarticularly.

2. The composition for use according to claim 1 , wherein the composition further comprises a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is incorporated into the anionic lipid composition.

3. The composition for use according to claim 1 or claim 2, wherein the anionic lipid composition comprises liposomes, lipid nanoparticles, solid lipid nanoparticles, and nanostructured lipid carriers.

4. The composition for use according to claim 3, wherein the anionic lipid composition comprises anionic liposomes.

5. The composition for use according to claim 4, wherein the liposomes comprise negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn-g / ycero-3- phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1 ,2-distearoyl-sn-g / ycero- 3-phospho-(1 ' -rac-glycerol) (DSPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2- dipalmitoyl-sn-glycero-3-phospho-(1-rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn-glycero-3- phospho-(l-rac-glycerol) (DOPG), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn-glycero-3- phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero-3- phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol-3'- 4'-5'-triphosphate) (DOPI-P3), or combinations thereof; optionally wherein) the liposomes further comprise one or more neutral or zwitterionic lipid, for example cholesterol, or a phosphocholine lipid (e.g. 1 ,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC) or 1 ,2-distearoyl-sn-glycero-3-phosphocholine (DSPG)), or combinations thereof.

6. The composition for use of any one of claims 1 to 5, wherein:(i) the polycationic aggregation agent comprises 2 or more separate positively charged sites at a pH range of between 6.0 and 8.0; and / or(ii) the polycationic aggregation agent is a polycationic pharmaceutically active agent, optionally wherein the polycationic aggregation agent is a polycationic anti-inflammatory agent, a polycationic anti-microbial agent, or a polycationic anti-fibrotic agent;optionally wherein the polycationic aggregation agent is an anti-inflammatory agent comprising an amino acid selected from the group consisting of lysine, alanine, glutamic acid, and tyrosine, or combinations thereof, optionally wherein the anti-inflammatory agent comprises a polymer comprising 40 to 100 amino acid polymer comprising four amino acids selected from L-alanine, L-lysine, L- glutamic acid, and L-tyrosine, for example where the anti-inflammatory agent is glatiramer or a pharmaceutically acceptable salt thereof (e.g. glatiramer acetate); or(iii) the polycationic aggregation agent is a polycationic anti-fibrotic agent; or(iv) the polycationic aggregation agent comprises a polyamine, optionally wherein the polyamine comprises chitosan, chitin, an aminoglycoside, poly(dimethyldiallylammonium chloride), poly(amidoamine) (PAM AM), inverse poly(amidoamine) (i-PAMAM), polypropylene imine) (PPI), a triazine-based polymer, polyallylamine, polyethyleneimine, poly(dimethylaminoethyl acrylate), a peptide or a polypeptide (e.g. polylysine, polyhistidine, polyornithine, polyarginine), a polyquaternium, or any combination thereof.

7. The composition for use of any one of claims 1 to 5, wherein the polycationic aggregation agent is a polycationic dendrimer; optionally wherein:(i) the dendrimer is a poly(amidoamine) (PAMAM) dendrimer, an inverse poly(amidoamine) (i-PAMAM) dendrimer, a polypropylene imine) (PPI) dendrimer, a triazine dendrimer, a phosphorus dendrimer, or a peptide dendrimer;(ii) the dendrimer is a G2 or G3 dendrimer, preferably wherein the dendrimer is a G3 dendrimer; and / or(iii) the dendrimer comprises an amino acid selected from the group consisting of lysine, leucine, arginine, asparagine, alanine, glutamic acid, tyrosine, and cysteine, or combinations thereof.

8. The composition for use of any one of claims 1 to 5, wherein the polycationic aggregation agent is a dendrimer selected from one of the following linear notations:(KA)8(KAK)4(KEKA)2KAKEAYCA-NH2 (consisting of SEQ ID NO: 1 to 4);(KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86);(k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90);(KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70);(kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74);(kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or(rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82), optionally wherein the dendrimer selected from one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) and (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8).

9. The composition for use according to any one of claims 2 to 8, wherein the pharmaceutically active agent is selected from the group consisting of anti-inflammatory agents, anti-fibrotic agents, anti-microbial agents, non-steroidal anti-inflammatory agents, corticosteroids and biological agents (e.g. peptides, proteins, stem cells, antibodies and antibody fragments); optionally wherein the pharmaceutically active agent is selected from the group consisting of triamcinolone, prednisone, hydrocortisone, methylprednisolone, dexamethasone, betamethasone, hyaluronic acid, certolizumab pegol, golimumab, belimumab, rituximab, rapamycin, torin-1 , torin-2, retinoic acid metabolism blocking agents (e.g. talarazole, liarozole), naproxen, ibuprofen, diclofenac, celecoxib, meloxicam, lornoxicam, kartogenin, dasatinib, quercetin, rhein, sinomenine, liquiritin, glatiramer acetate, insulin-like growth factor 1 (IGF 1), Resolvin D1 , fibroblast growth factor 18 (FGF 18), bone morphogenetic protein (BMP) 7, an anti-IL-1 agent (e.g. canakinumab, anakinra, ilonacept, gevokizumab), an anti-TNF agent (e.g. infliximab, adalimumab, etanercept), Botulinum toxin A, a JAK inhibitor (e.g. tofacitinib, filgotinib, upadacitinib, TD-1473, Brepocitinib (PF-06700841), PF-06651600), pirfenidone, or nintedanib, cathelicidin, LL-37, polymyxin B, magainin, murepavadin, MK-8722, or combinations thereof.

10. The composition for use according to any one of claims 1 to 9, wherein the joint disease or disorder is selected from arthritis, osteoarthritis, arthrofibrosis, rheumatoid arthritis, gout, bursitis, bacterial arthritis, juvenile idiopathic arthritis, psoriatic arthritis, reactive arthritis, ankylosing spondylitis, tendinopathy, polymyalgia rheumatica, Paget’s disease, lupus, Sjogren's Syndrome, osteonecrosis, neuropathic arthropathy, or Lyme disease; optionally wherein the joint disease or disorder is osteoarthritis.

11. The composition for use according to any one of claims 1 to 10, wherein composition comprises aggregates comprising the anionic lipid composition (e.g. liposomes) and the polycationic aggregation agent.

12. The composition for use according to any one of claims 1 to 11 , wherein the composition forms a sustained release depot following intraarticular administration to the subject.

13. A composition comprising:• an anionic liposome; and• a polycationic aggregation agent, wherein the polycationic aggregation agent is:(i) a cationic dendrimer aggregation agent comprising one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4); (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8); (k{NLE}y)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 83 to 86); (k{NLE}y)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 87 to 90); (KL)8(KKL)4(KKL)2KKL (consisting of SEQ ID NO: 67 to 70); (kl)8(kkl)4(kll)2kk(Ci6)k(Ci6) (consisting of SEQ ID NO: 71 to 74); (kl)8(kkl)4(kll)2kllll (consisting of SEQ ID NO: 75 to 78); or (rl)8(krl)4(krl)2kk(Ci8) (consisting of SEQ ID NO: 79 to 82); or(ii) a polycationic aggregation agent selected from the group consisting of: inverse poly(amidoamine) (i-PAMAM), polyethyleneimine (branched or straight-chain), tobramycin, glatiramer acetate, polymyxin B, polylysine, apidaecin 1b, LL-37, polyarginine, or Walk11.

3. optionally wherein:(i) the composition comprises:• an anionic liposome; and• a cationic dendrimer aggregation agent, wherein the cationic dendrimer aggregation agent comprises one of the following linear notations: (KA)8(KAK)4(KEKA)2KAKEAYCA-NH2(consisting of SEQ ID NO: 1 to 4) or (KA)8(KKAKE)4(KYKAKA)2KAYKKA-OH (consisting of SEQ ID NO: 5 to 8);(ii) the composition further comprises a pharmaceutically active agent, optionally wherein the pharmaceutically active agent is encapsulated in the anionic liposome;(iii) the anionic liposome comprises negatively charged lipids selected from the group consisting of 1 ,2- dipalmitoyl-sn-g / ycero-3-phosphate (DPPA), 1 ,2-dioleoyl-sn-g / ycero-3- phosphate (DOPA), 1 ,2-distearoyl-sn-g / ycero-3-phospho-(1' -rac-glycerol) (DSPG), 1 ,2- dioleoyl-sn-glycero-3-phospho-l-serine (DOPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1-rac-glycerol) (DPPG), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1-rac-glycerol) (DOPG), 1 ,2- dipalmitoyl-sn-glycero-3-phospho-l-serine (DPPS), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '- myo-inositol) (DPPI), 1 ,2-dipalmitoyl-sn-glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'- triphosphate) (DPPI-P3), 1 ,2-dioleoyl-sn-glycero-3-phospho-(1 '-myo-inositol) (DOPI), or 1 ,2- dioleoyl -sn-glycero-3-phospho-(1 '-myo-inositol-3'-4'-5'-triphosphate) (DOPI-P3), or combinations thereof; and / or(iv) the anionic liposome further comprises one or more neutral or zwitterionic lipid, for example, cholesterol, or a phosphocholine lipid (e.g. 1 ,2-dipalmitoyl-sn-glycero-3- phosphocholine (DPPC) or 1 ,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)), or combinations thereof.14 The composition according to claim 13, wherein the composition comprises aggregates comprising the polycationic aggregation agent (e.g. the cationic dendrimer aggregation agent) and a plurality of the anionic liposomes.

15. A kit comprising: a) a first container comprising an anionic lipid composition; b) a second container comprising a polycationic aggregation agent; and c) instructions to combine a) with b) to provide the composition for use according to any one of claims 1 to 12; optionally wherein the first container further comprises a pharmaceutically active agent incorporated into the anionic lipid composition.

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