Hemostatic compositions and methods using composite polymer particles

Abstract

The embodiments herein provide hemostatic compositions, methods, and kits comprising composite polymer particles. Upon contact with blood or other physiological fluids, the composite particles adsorb fluid and aggregate into a shape-retentive mass that halts bleeding. In certain embodiments, the particles comprise polymers of 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, or combinations thereof. The particles may be used alone or blended with additional hemostatic agents. Methods of inducing hemostasis are provided for diffuse oozing, or surgical, mucosal, organ surface, fragile tissue or traumatic bleeding, including in patients receiving anticoagulant or antiplatelet therapy. Kits comprising sterile packages of composite particles, optionally with applicators, substrates, or sprays, are disclosed. The compositions exhibit intrinsic hemostatic activity and synergistically enhance the performance of conventional hemostats, achieving rapid clotting. After hemostasis is achieved, the compositions remain in situ as a conforming protective layer, reducing the need for additional covering materials and decreasing risk of re-bleeding.

Description

Docket No. 89380.0008\WOHEMOSTATIC COMPOSITIONS AND METHODS USING COMPOSITE POLYMER PARTICLESGOVERNMENT FUNDING

[0001] This invention was made with government support under Contracts No. W81XWH21P0019 and No. W18WXH22C0045, awarded by the United States Department of Defense. The government has certain rights in the invention.RELATED APPLICATIONS

[0002] This application claims the priority benefit of United States Provisional Application No. 63 / 701,373, filed 30 September 2024, which is incorporated fully herein by reference for all purposes.FIELD

[0003] The present embodiments relate to medical devices, compositions, and methods for inducing hemostasis. More specifically, the embodiments provide composite polymer particles capable of adsorbing blood and bodily fluids, forming aggregates that arrest bleeding. Applications include trauma care, surgical procedures, mucosal bleeding, organ surface hemorrhage, fragile tissue bleeding, chronic bleeding, and veterinary medicine.BACKGROUND

[0004] Bleeding is a leading complication across a spectrum of clinical indications, including traumatic bleeding, chronic bleeding, surgical bleeding, diffuse oozing, mucosal and organ surface bleeding, fragile tissue prone to re-bleeding, and bleeding in anti coagulated patients. There remains an unmet need for a hemostatic composition that rapidly halts bleeding in these indications.SUMMARY

[0005] The present embodiments provide compositions comprising composite polymer particles that exhibit intrinsic hemostatic activity, and methods of using and making these compositions. These hemostatic compositions comprising composite polymer particles are capable of adsorbing blood and bodily fluids, thereby forming aggregates that arrest bleeding. Specifically, upon contact with blood or other physiological fluids, the composite particles adsorb fluid and aggregate into a shape-retentive mass that halts or significantly reduces bleeding.Docket No. 89380.0008\WO

[0006] An aspect of the present embodiments provides methods of inducing hemostasis useful in treating diffuse oozing, surgical bleeding, mucosal bleeding, organ surface bleeding, fragile tissue bleeding, and traumatic bleeding, including in patients receiving anticoagulant or antiplatelet therapy. The compositions provided herein exhibit intrinsic hemostatic activity and synergistically enhance the performance of conventional hemostats, achieving rapid clotting without compression and overcoming limitations of current technologies. Further, after hemostasis is achieved, the composite particles remain in situ as a conforming protective layer, reducing the need for additional covering materials and decreasing risk of re-bleeding.

[0007] In certain embodiments, the particles comprise polymers of 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, or combinations thereof. In one embodiment, the composite particles comprise poly(2-hydroxyethyl methacrylate) (pHEMA), poly(2- hydroxypropyl methacrylate) (pHPMA), or combinations thereof. The particles may be used alone or blended with additional hemostatic agents including, without limitation, chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, or zeolite.

[0008] In at least one embodiment, the composite particles composition comprises at least one pharmaceutical agent, included at a concentration range of about 0.01% by weight to about 10.0% by weight of the hemostatic composition. In at least one embodiment, the pharmaceutical agent is included at a concentration range of about 0.01% by weight to about 10.0% by weight of the composite polymer particles.

[0009] In at least one embodiment, the adsorbent composite polymer particles are prepared from a suspension of poly-2-hydroxyethyl-methacrylate (pHEMA) particles and poly- 2-hydroxypropylmethacrylate (pHPMA) particles, for example at a ratio of pHEMA:pHPMA of about 80:20 to about 90: 10, inclusive and including ratios therebetween of any proportional mix, such as a pHEMA:pHPMA ratio of about 85: 15. In at least one embodiment, the composite particles are blended with at least one additional hemostatic agent such as chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, zeolite, oxidized cellulose, starchderived microparticles, silica-based particles, poly-N-acetylglucosamine, microfibrillar collagen, or combinations thereof, present at about 0.01% to 10% by weight.

[0010] At least one embodiment provides compositions of composite polymer particles that exhibit intrinsic hemostatic activity. Upon hydration with blood, the particles aggregate into a spongy mass that entraps red cells, platelets, and proteins, halting bleeding.

[0011] In at least one embodiment, the hemostatic composition of composite polymer particles further includes at least one pharmaceutical agent, such as chitosan tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, zeolite, oxidized cellulose, starch-derived microparticles, silica-based particles, poly-N-acetylglucosamine, microfibrillar collagen, orDocket No. 89380.0008\WO combinations thereof, whereby composite particles accelerate and complete clotting by uniformly distributing these agents through a solvent front. Surprisingly, the combination of the composition comprising composite polymer particles and an additional hemostatic agent, such as chitosan or tranexamic acid, was shown to provide synergistic hemostatic activity.

[0012] In another aspect of the present embodiments, hemostatic composition of composite polymer particle described herein may further provide antimicrobial properties, debriding properties, anti-biofilm properties, or provide an environment that decreases the inflammatory response by signaling a proliferative rather than an inflammatory response.

[0013] The present embodiments further provide methods of inducing hemostasis by applying the hemostatic compositions described herein. The methods of applying the hemostatic compositions are useful in trauma, surgical, mucosal, and other bleeding contexts, wherein the composite polymer particles aggregate and persist in situ as a conforming protective layer after bleeding is arrested, reducing the need for additional covers. In one embodiment of the method, the composition is applied to control diffuse oozing from surgical beds, organ resections, or bone edges. In another embodiment of the method, the composition is applied to bleeding from surgical or procedural incisions or excisions, such as skin incisions, biopsy or puncture sites, tumor excisions, or tissue harvest and debridement sites. In another embodiment of the method, the composition is applied to grafting procedures including skin graft donor sites, graft recipient beds, vascular grafts, orthopedic grafts, bone marrow harvests, or organ transplant procedures. In another embodiment of the method, the composition is applied to dental or oral and maxillofacial procedures including tooth extraction, periodontal surgery, or jaw reconstruction. In another embodiment of the method, the composition is applied to cosmetic and reconstructive procedures including flap surgery, skin excision, bum excision and debridement, cosmetic grafting, or hair transplantation donor sites. In another embodiment of the method, the composition is used to control surgical bleeding in thoracic, cardiac, orthopedic, neurosurgical, vascular, dental, grafting or gynecologic procedures. In another embodiment of the method, the composition is used to manage mucosal bleeding, such as epistaxis, gastrointestinal hemorrhage, or oral cavity bleeding. In another embodiment of the method, the composition is applied to ophthalmic bleeding, including conjunctival, scleral, orbital, or periocular bleeding, for example following trauma, surgery, or anticoagulant-related hemorrhage. In another embodiment of the method, the composition is used to control organ surface bleeding including hepatic, splenic, renal, peritoneal, pleural, and bone or marrow bleeding sites. In another embodiment of the method, he composition is applied to abdominal or retroperitoneal bleeding, such as pancreatic procedures, partial nephrectomy, or trauma to the renal or adrenal regions.Docket No. 89380.0008\WO

[0014] In another embodiment of the method, the composition is applied to fragile tissues such as graft sites, friable tumors, fragile elderly skin, or mucosa prone to shear-induced re-bleeding.

[0015] In another embodiment of the method, the composition is used to induce hemostasis in grafting procedures, including skin graft donor sites, graft recipient beds, bone marrow harvest sites, vascular grafts, orthopedic grafts, or organ transplant procedures. The composition provides rapid hemostasis and remains in situ as a conforming protective layer, reducing re-bleeding and eliminating the need for separate hemostatic and covering materials.

[0016] In another embodiment of the method, the composition is applied to traumatic bleeding, including lacerations, blunt trauma, penetrating wounds, gunshot injuries, blast injuries, and chronic wound bleeding such as venous ulcers, diabetic ulcers, and pressure injuries. In another embodiment of the method, the composition is used in patients receiving anticoagulant or antiplatelet therapy, including warfarin, direct oral anticoagulants (DOACs), aspirin, or clopidogrel. In another embodiment of the method, the composition is used in veterinary applications, for surgical or traumatic bleeding in animals.

[0017] An aspect of the present embodiments further provides kits useful for practicing methods of inducing hemostasis as described herein. In at least one embodiment, a kit comprises at least one package of sterile composite particles, optionally with instructions for use, applicators, substrates, or sprays. In one embodiment of the kit, the sterile composite particles further comprise at least one pharmaceutical agent, such as a hemostatic agent, for example chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, or zeolite. In another embodiment of the kit, the kit comprises at least one package of sterile composite particles and at least one package of sterile pharmaceutical agent, such as a hemostatic agent, for example chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, or zeolite. One embodiment provides a kit comprising a sterile package of composite particles in a vial, sachet, or blister. In another embodiment, the kit further includes an applicator, syringe, spray device, gauze, mesh, or sponge substrate impregnated with composite particles. In certain embodiments, the kit comprises the composite polymer particles prepared by dry blending with other hemostatic powders. In other embodiments, the kit comprises a combination of dry composite particles packaged with a separate liquid hemostatic agent, such as TXA, thrombin solution, fibrinogen solution, tranexamic acid solution, or other pro-coagulant formulations. Upon use, the liquid agent may be applied to the composite particles at the site of bleeding, inducing aggregation and clot formation. In another embodiment, the kit comprises at least two separate dry powders configured to be combined or dry blended at the site of use immediately prior to application. Such powders may include the composite polymer particles and one or moreDocket No. 89380.0008\WO hemostatic agents, additives, or excipients, allowing the formulation to be tailored at the point of care for specific bleeding scenarios. In another embodiment, the kit is configured for military or prehospital use and ruggedized for field deployment.

[0018] At least one embodiment provides compositions comprising shape-transforming adsorbent composite polymer particles that can rapidly adsorb blood and fluids and can further incorporate one or more clotting agents, such that the rapid adsorption of fluids leads to a large volume of blood contacting a high surface area of clotting agent in a short time period. In one aspect, the embodiments provide adsorbent composite particles that are dehydrated and blended with at least one material that has the chemical structure necessary to increase the rate of hemostasis cascade in the presence of arterial bleeding. Accordingly, the dehydrated polymers adsorb blood rapidly using the blood as a hydrating fluid within and between the composite polymer particles and the polymer particles aggregate transforming from a shape conforming material to a shape retentive material. In at least one embodiment, the hemostatic agent is dispersed uniformly within the polymer particles and present when the adsorption of blood occurs causing a rapid interaction between blood, the components of blood and the polymers and hemostatic agents. In at least one embodiment, the rapid movement of the blood solvent front through the materials causes rapid clotting within and around the polymer particles producing a rapid clot at the site of bleeding.

[0019] One embodiment provides for the composition of the polymer particles, as they hydrate and aggregate thereby transforming from a shape-conforming powder to a shape- retentive aggregate material in which the total percent blood adsorbed of the final aggregate material is 20-30% greater than the hydration percent of an isotonic solution such as saline.

[0020] One embodiment provides for the combination of polymer particles of 85: 15 pHEMA:pHPMA (wt:wt) polymers aggregating to an equilibrium percentage of water from 65% to 75 % in normal isotonic saline, and aggregating to an equilibrium percentage of blood of 85% to 90%.

[0021] Another aspect of the present embodiment provides for the trapping of blood components including cells, and proteins in and between the particles and forming the matrix to hold blood and components as a clotting cascade is initiated to form a clot.

[0022] Another aspect of the present embodiments provides for the rate of clot formation and hemostasis to occur faster in the presence of the polymer particles than with the blood alone not in the presence of the polymer particles or other agents that induce clotting. The blood flow within the solvent front interacts with the polymer particles and the polymer swells as the blood moves into the polymer matrix, hydrating and trapping the blood and its constituents. The clotting agent materials dispersed within the polymer particles are trapped in the matrix as theDocket No. 89380.0008\WO blood fluid hydrates and aggregates the polymer particles and cells responsible for clotting are rapidly exposed to the clotting agent materials. This combination of blood flow and trapping within the polymer matrix and concomitant clotting forms a clot from the blood faster than the polymer particles alone or the clotting agent alone and with a higher capacity for capturing the blood within the polymer-clot matrix.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. l is a cartoon showing a schematic of polymer particles loosely clustered around a blend of one or more hemostatic agents. When the collection of polymer particles comes in contact with blood, the blood moves into the polymer particles in a solvent front performing a combination of capillary pumping of the blood into the polymers as they hydrate and alternatively causing the polymer particles to aggregate together. Further, the platelets within the fluid flow interact with a large surface are of mixed hemostatic agents in a short time period during this adsorption.

[0024] FIG. 2 a schematic showing an embodiment comprising three layers of shape- retentive material placed on a wound, in which at least one layer of which induces hemostasis, and at least one layer of which releases a pharmaceutical agent. J, = direction of diffusion of agent(s) from material to wound surface.DETAILED DESCRIPTION

[0025] It should be understood that this invention is not limited to the particular embodiments, methodology, protocols, and reagents, etc., described herein and as such may vary. The terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention, which is defined solely by the claims. The invention is further illustrated by examples herein, which are not intended to limit the scope of the claims.

[0026] All patents and other publications identified are incorporated herein by reference for the purpose of describing and disclosing, for example, the methodologies described in such publications that might be used in connection with the present embodiments, but are not to provide definitions of terms inconsistent with those presented herein. These publications are provided solely for their disclosure prior to the filing date of the present application. Nothing in this regard should be construed as an admission that the inventors are not entitled to antedate such disclosure by virtue of prior invention or for any other reason. All statements as to the date or representation as to the contents of these documents is based on information available to theDocket No. 89380.0008\WO applicants and do not constitute any admission as to the correctness of the dates or contents of these documents.

[0027] As used herein and in the claims, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly indicates otherwise. Throughout this specification, unless otherwise indicated, “comprise,” “comprises,” and “comprising” are used inclusively rather than exclusively, so that a stated integer or group of integers may include one or more other non-stated integers or groups of integers. The term “or” is inclusive unless modified, for example, by “either.” Thus, unless context indicates otherwise, the word “or” means any one member of a particular list and also includes any combination of members of that list.

[0028] All numerical designations, e.g., pH, temperature, time, concentration, and molecular weight, including ranges, are approximations that may be varied by increments of ±1% to ±10% as would be accepted by one skilled in the art. Accordingly, other than in the operating examples, or where otherwise indicated, all numbers expressing quantities or reaction conditions used herein should be understood as modified in all instances by the term “about.” It is understood that where a parameter range is provided, all integers within that range, and tenths thereof, are also provided by the invention. For example, “10-50%” includes 10.0%, 10.1%, 10.2%, 10.3%, 10.4%, etc., up to and including 50.0%.

[0029] In order that the present disclosure can be more readily understood, certain terms are first defined. Additional definitions are set forth throughout the detailed description.

[0030] As used herein, “composite particles” means finely divided polymer-based particles, optionally blended with at least one pharmaceutical agent (e.g., hemostatic agent), that adsorb fluid and aggregate into a shape-retentive mass.

[0031] As used herein, “hemostasis” means arrest of bleeding by clot formation and / or mechanical occlusion.

[0032] As used herein, “synergistic effect” occurs when two or more substances or other agents combine to produce an effect greater than the sum of their individual effects. Accordingly, “synergy” means the interaction substances, or other agents to produce a combined effect greater than the sum of their separate effects. In the context of the present embodiments, “synergy” means enhanced hemostatic performance when composite particles are combined with another agent, e.g., a hemostatic pharmaceutical agent, relative to either component alone.

[0033] As used herein, the term “shape-conforming” means that a material will take the shape of its container. In applications in tissue repair, the shape-conforming material may start as a powder or fine flakes and will conform to a tissue surface or defect shape.

[0034] As used herein, the term “shape-retentive” means that a material retains a shape as a fixed material and will not conform to a container. For example, if a shape-retentiveDocket No. 89380.0008\WO material is shaped as a cylinder or sphere, the material and will retain the shape of the cylinder or sphere regardless of its surrounding environment. A shape-retentive material may deform under pressure but if the pressure is released, a shape retentive material will return to the original shape. An example would be a shape-retentive foam ball that has the shape of a sphere that can be deformed by pressure to temporarily assume a shape of a disc, but when the pressure is removed the shape conforming ball will return to the original sphere shape.

[0035] As used herein, the term “shape-transforming” refers to a property of a material that allows the material to initially act as shape-conforming material but then transform to a shape-retentive material. Accordingly, the adsorbent polymer particle materials are shapeconforming. After a transformation by contact with physiological fluids, the material aggregates and becomes shape-retentive. In tissue applications, the shape-conforming powder is applied to a tissue site of irregular, undefined geometry, the material conforms to the tissue surface, filling voids, and then transforms to a shape-retentive material that retains the three-dimensional shape of the tissue geometry.

[0036] As used herein, the term “gel” refers to a three-dimensional structure comprising adsorbent composite particles prepared as a shape-conforming gel that, after contact with a physiological surface, transitions to a shape-retentive state.

[0037] As used herein, a “suspension” refers to a uniformly distributed, stable dispersion of solid particles in a liquid in which the solid is not soluble. By “stable” is meant that solids remain uniformly dispersed for at least 24 hours, unless subjected to disrupting external forces such as, centrifugation or filtration.

[0038] The term “polar liquid,” as used herein has the meaning generally understood by those skilled in the chemical art. In brief, a polar liquid is one in which the electrons are unevenly distributed among the atoms of its molecules and therefore create an electrical dipole. Examples of polar liquids include, without limitation, water, where the oxygen atom bears a partial negative charge and the hydrogen atoms a partial positive charge, and alcohols, wherein the O-H moiety is similarly polarized.

[0039] A “subject” is intended to be an animal such as a mammal, avian or otherwise. Mammals include, but are not limited to, mice, rats, monkeys, dogs, cats, humans, farm animals such as cattle or sheep, sport animals such as horses, zoo animals, and domestic pets. A subject may be a human patient or a non-human patient.

[0040] As used herein, a “monomer” has the meaning understood by those skilled in the chemical art. That is, a monomer is a small chemical compound that is capable of forming a macromolecule of repeating units of itself, i.e., a polymer. Two or more monomers (that may be the same or different monomer types, i.e., different molecules) may react to form a polymer inDocket No. 89380.0008\WD which each of the monomers is repeated numerous times, the polymer being referred to as a copolymer to reflect the fact that it is made up of more than one type of monomer.

[0041] As used herein, the term “plurality” simply refers to more than one, i.e., at least two.

[0042] As used herein the term “dry weight” means the weight of particles without the weight of liquid(s).

[0043] The terms “pharmaceutical agent” or “pharmaceutically active agent” refer to both small molecule and to macromolecular compounds used as drugs, devices, or diagnostic agents and is not limited to therapeutic agents. Small molecule compounds include, without limitation, hemostatic agents, antimicrobials (including antibiotics, antifungals, antivirals) chemotherapeutics (in particular platinum compounds and taxane and its derivatives), analgesics, antidepressants, antibiotics, anti-allergenics, anti -rejection agents such as immunosuppressive or tolerance-inducing agents, debriding agents, antiarrhythmics, antiinflammatory compounds, CNS stimulants, sedatives, anti-cholinergics, anti-arterioscl erotics, and diagnostic compounds such as dyes or radioligands and the like. Macromolecular compounds include, without limitation, monoclonal antibodies (mAbs), antibody fragments (Fabs), proteins, peptides, cells, antigens, nucleic acids, genes, proteins, growth factors, antigens, polypeptdes, DNA, RNA, ribozymes, enzymes, growth factors, secretomes, extracellular vesicles (EVs), viable cells, and the like. A pharmaceutical agent may be intended for topical, localized, or systemic use. Examples of pharmaceutically active agents include, without limitation, biomedical agents and biologically active substances such as hemostatic agents, antimicrobials, polypeptides or proteins, growth factors, monoclonal antibodies or portions thereof, and antigens or immunogens. Dosing of pharmaceutically active or therapeutic agents can be modified and determined based on existing therapeutic dosage levels with a high and low range around the recommended dosage levels. Dosages can be maintained within the non-toxic range established by the FDA utilizing US-Pharmacopeia (USP) standards.

[0044] “Therapy” refers to treatment intended to relieve or heal a disorder in a subject.

[0045] As used herein, the term “cross-linking agent” refers to a di-, tri-, or tetrafunctional chemical entity that is capable of forming covalent bonds with functional groups on polymeric strands resulting in a three-dimensional structure.

[0046] As used herein, the term “hydrogen bond” refers to the electronic attraction between a hydrogen atom covalently bonded to a highly electronegative atom and another electronegative atom having at least one lone pair of electrons. The strength of a hydrogen bond, about 23 kJ (kilojoules) mol’1, is between that of a covalent bond, about 500 kJ mol’1, and a vanDocket No. 89380.0008\WO der Waals attraction, about 1.3 kJ mol'1. Hydrogen bonds have a marked effect on the physical characteristics of a composition capable of forming them.

[0047] As used herein, a “charged” gel particle refers to a particle that has a localized positive or negative charge due to ionic content of the monomers making up the polymer strands of the particle and the environment in which these particles find themselves. For example, without limitation, particles comprising acrylic acid as a co-monomer will, under basic conditions, exist in a state in which some or all of the acid groups are ionized, i.e., -COOH becomes -COO . Another example is the amino (-NH2) group, which, in an acidic environment, will form an ammonium (-NHC) ion.

[0048] In general, an “excipient” or “pharmaceutically acceptable excipient” refers to an inert substance added to a therapeutic composition to facilitate its administration. A “pharmaceutically acceptable excipient” does not cause significant irritation to an organism and does not abrogate the biological activity and properties of the administered compound (pharmaceutical or therapeutic agent). The term “pharmaceutically acceptable excipient” encompasses any of the standard pharmaceutical carriers, such as a phosphate buffered saline, water, emulsions, and various types of wetting agents. Excipients can include stabilizers and preservatives. Examples, without limitation, of excipients include calcium carbonate, calcium phosphate, various sugars (e.g., glucose and dextrose), types of starch, cellulose derivatives, gelatin, vegetable oils, and polyethylene glycols. For examples of carriers, stabilizers, and adjuvants, see REMINGTON’ S PHARMA. SCI. 15th Ed. (Mack Publ. Co., Easton, Penn. 1975).

[0049] As used herein, the term “hydrophilic / hydrophobic interactions” refers to the inter-or intra-molecular association of chemical entities through physical forces, whereby hydrophilic compounds or hydrophilic regions of compounds tend to associate with other hydrophilic compounds or hydrophilic regions of compounds, and hydrophobic compounds or hydrophobic regions of compounds tend to associate with other hydrophobic compounds or hydrophobic regions of compounds.

[0050] As used herein, the term “occlude” has the meaning generally understood by those skilled in the chemical art, that is, to absorb and retain a substance for a period of time. Regarding the embodiments provided herein, in at least some embodiments substances such as pharmaceutical agents, may be absorbed by and retained in, i.e., occluded by, the composite polymer particles of the present embodiments during the preparation of compositions comprising these particles. Similarly, as used herein, the term “entrapped” refers to the retention for a period of time of a substance in the voids between the particles within the compositions comprising composite particles of the present embodiments.Docket No. 89380.0008\WO

[0051] As used herein, the term “elastic modulus” refers to the stiffness of a given material, and is the ratio of linear stress in a body to the corresponding linear strain within the limits of elasticity.

[0052] A “pharmaceutical composition” is intended to include the combination of an pharmaceutical agent with an excipient or the composite particle compositions described herein, in which the pharmaceutical composition suitable for diagnostic or therapeutic use in vitro, in vivo, or ex vivo.

[0053] An “effective amount” is an amount sufficient to effect beneficial or desired results. Methods for determining the effective amount, as determined by the desired or beneficial result, are well-known in the art.

[0054] The present embodiments provide hemostatic compositions comprising composite polymer particles, methods of inducing hemostasis using these hemostatic compositions, and kits comprising these hemostatic compositions. Upon contact with blood or other physiological fluids, the composite particles adsorb fluid and aggregate into a shape- retentive mass that halts bleeding. These compositions, methods, and kits, fill an unmet need for hemostatic therapies.

[0055] Currently, a principal method for treating bleeding is to stop the flow of blood by applying pressure with a bandage to facilitate formation of a clot. Existing hemostatic technologies can be divided into physical matrix agents, mineral agents, and biologically active agents. Physical scaffolds such as Surgicel® (oxidized regenerated cellulose), Gelfoam® (gelatin foam), and Avitene® (microfibrillar collagen) require compression and are less effective in diffuse or persistent bleeding. Mineral agents such as QuickClot® (zeolite, later kaolin) concentrate clotting factors but may cause exothermic reactions and require multiple layers. Biologically active agents such as thrombin, fibrin sealants, and recombinant factors accelerate coagulation but are costly, and may be unstable or unsuitable for bulk bleeding. Chitosan dressings (HemCon®, Celox®) are adhesive but variable in performance. These limitations underscore the need for a universal hemostat effective across diverse bleeding scenarios, stable at room temperature, and usable without compression. Further, current bandages are often too stiff and too rigid to fit into a narrow space of a cavity or, if sufficiently pliable, do not adequately conform to irregular tissues geometries to cause rapid and effective hemostasis. Moreover, it is not always practical or possible to maintain sufficient pressure to a bleeding site, such that there remains a need for alternative materials that can clot a bleeding site.

[0056] The compositions described herein advantageously exhibit intrinsic hemostatic activity, and further synergistically enhance the performance of conventional hemostats,Docket No. 89380.0008\WO achieving rapid clotting without compression and overcoming limitations of current technologies. Further, after hemostasis is achieved, the composite particles remain in situ as a conforming protective layer, reducing the need for additional covering materials and decreasing risk of re-bleeding.

[0057] As noted above, the present embodiments provide hemostatic compositions comprising composite polymer particles. Upon contact with blood or other physiological fluids, composite particles adsorb fluid rapidly through solvent front migration. This hydration causes the particles to aggregate and transform from a shape-conforming powder into a shape-retentive material. Blood components including red blood cells, white blood cells, platelets, and serum proteins become entrapped within and between the particles, producing a stable clot.

[0058] In certain embodiments, after bleeding is arrested, the composite polymer particles remain in situ as a conforming, protective layer over the injured site. This layer protects against external contamination, provides a moisture-balanced environment, and reduces the risk of re-bleeding caused by shear, friction, or fragile tissue disruption. Unlike conventional hemostats that require removal or protection with a separate cover, the compositions described herein function both as a hemostatic agent and as a persistent protective layer. Unlike mineralbased hemostatic agents such as zeolite, the composite polymer particles of the present invention do not exhibit exothermic reactions upon fluid adsorption. This provides improved safety, reduces risk of injury, and maintains clot integrity without thermal degradation.

[0059] In at least one embodiment, the composite polymer particles comprise polymers of 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, or combinations thereof. The particles may be used alone or combined with at least one additional hemostatic agent, such as chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, or zeolite.

[0060] Another aspect of the present embodiments provides methods of inducing hemostasis for diffuse oozing, surgical bleeding, mucosal bleeding, organ surface bleeding, fragile tissue bleeding, and traumatic bleeding, including in patients receiving anticoagulant or antiplatelet therapy, comprising application of the compositions described herein. Bleeding may arise, for example, from surgery or injury, for example traumatic accidents, or from projectiles from weapons or improvised explosive devices. Such injuries can result in an arterial puncture, a venous puncture, an arterial laceration, or a venous laceration. Each injury can have a unique size or shape. Often, the extent of the tissue damage may not be fully determined. The use of shape-transforming materials as described herein allows treatment of several injury types without the need to predetermine the size or shape of a single article to promote hemostasis.

[0061] Another aspect of the present embodiments provides kits comprising sterile packages of composite particles, optionally with instructions, applicators, substrates, or sprays.Docket No. 89380.0008\WOThe compositions exhibit intrinsic hemostatic activity, and further synergistically enhance the performance of conventional hemostats, achieving rapid clotting without compression and overcoming limitations of current technologies.

[0062] Regarding delivery to the site of bleeding, an embodiment of the composite polymer particles composition may be sprinkled from a package onto a bleeding surface. Altrazeal® transforming powder dressing (Altrazeal Life Sciences, Addison, Texas, USA) is an embodiment of the composition, but previous methods of use of Altrazeal have not included hemorrhagic / hemostatic control as described herein. Powders provide advantageous application on irregular surfaces and can also be mixed with sterile solutions, for example saline or solutions comprising a pharmaceutical agent(s).

[0063] As provided herein, the hemostatic composite particles compositions are prepared from the synthetic family of n-hydroxy-n-alkyl-m-methylprop-2-enoate polymers where n and m can range from 1-3 and alkyl can be methyl, ethyl, or propyl. In at least one embodiment, the ACP composition is composed of one or more polymers from the synthetic family of polymers of n-hydroxy-n-alkyl-m-methylprop-2-enoate polymers where n and m can range from 1-3. Alkyl can be, for example, methyl, ethyl, butyl or propyl. In at least one embodiment, the ACP comprises the polymers described in Table 1 and Table 2 herein. These polymer combinations are selected to ensure rapid transformation from shape-conforming to shape-retentive states upon contact with blood and other physiological fluids, enabling safe application to bleeding tissues. Selection among these variations provides tunable physical properties, such as tensile strength, elasticity, fluid absorption and retention, and rate of shape transformation, which can be optimized for different clinical applications.

[0064] In at least one embodiment, the hemostatic composite particles composition comprises at least one pharmaceutical agent or pharmaceutically acceptable excipient. In at least one embodiment, at least one pharmaceutical agent is mixed with polymers during production of adsorbent composite particles. In at least one embodiment, at least one pharmaceutical agent is mixed (dry blended) with the composite particles. In at least one embodiment, at least one pharmaceutical agent is provided as a solution and contacted with the composite particles composition at the time of application to the bleeding tissue. In at least one embodiment, at least two pharmaceutical agents are provided as a solution or suspension and contacted with the composite particles composition at the time of application to the bleeding tissue, thereby enabling combination therapy at the site where hemostasis is needed.

[0065] In at least one embodiment, the hemostatic composite particles composition hydrates with a liquid that contains at least one pharmaceutical agent suspended or dissolved in the liquid so that the composition adsorbs the liquid containing the suspended or dissolvedDocket No. 89380.0008\WO pharmaceutical agent as the composition transforms and occludes the agent in the shapetransforming matrix. This mechanism enables localized loading and sustained release of therapeutic agents directly at the site of application.

[0066] In at least one embodiment, the shape-retentive (transformed) composite particles composition provides that after hydration and entrapping / occluding of at least one pharmaceutical agent, the at least one agent is released from the composition into the contacted tissue over time in a predetermined, sustained, or controlled release profile. The release profile can be tailored by adjusting polymer composition, particle size, or agent concentration. In certain embodiments, polymer ratios, crosslinking density, or hydrophilicity may be varied to modulate release kinetics.

[0067] Accordingly, to manage other aspects of presentations requiring hemostatic therapy, the present hemostatic composite particles composition can be formulated with additional hemostatic agents, anti-inflammatory agents, antimicrobial agents or combinations of such agents, thereby delivering a comprehensive kit of topical therapeutics that optimize the hemostatic material’s performance. These compositions may be easily combined with the requisite agents by dry-blending with their powdered forms or by hydrating with their liquid forms that are easily available in the market in the form of ophthalmic or ear droppers (lower doses) and IV injections (higher doses). An object of this aspect provides a comprehensive kit that combines selective, safe, and well-accepted, cost-effective, FDA-approved and commercially available agents with the various embodiments of hemostatic composite particles compositions described herein. When aggregates form, covalent crosslinking of the methacrylate backbone occludes the active agents within the heterogeneous polymer network and ensure a sustained drug release. This entrapment mechanism slows diffusion, allowing predictable, tunable release kinetics over hours to days. Production methods may be adapted to vary sequencing and timing of release of actives. Various dose ranges are selected based on FDA approved dosages available in the market that can be further cross-referenced versus clinical dosage information available for their use in TBI. The various dosages are tested for absolute and relative performance to select the dosage level with the most clinically optimal release profile. The combinations expand the composition’s capability for use in diverse environments.

[0068] Accordingly, in at least one embodiment, the hemostatic composite particles composition further comprises at least one pharmaceutical agent, thereby providing an in situ shape-retentive device that delivers a pharmaceutical agent from the device in contact with the bleeding tissue surface. In at least one embodiment, the hemostatic composition comprises at least one therapeutic pharmaceutical agent, such as a growth factor, neurotrophic growth factor, anti-inflammatory agent (e.g., a steroid), pain-management agent (analgesic), antioxidant,Docket No. 89380.0008\WO enzyme, antimicrobial agent, anti-seizure agent, hyperosmolar agent, biofilm- inhibiting / dispersal agent, or a combination of any of these. In an aspect of these embodiments, the hemostatic composition provides an environment that decreases the inflammatory response by signaling a proliferative rather than an inflammatory response. In at least one embodiment, the hemostatic composition comprises both an antimicrobial agent and a hemostatic agent. In at least one embodiment, the hemostatic composition comprises both an antimicrobial agent and a steroid. In at least one embodiment, the pharmaceutical agent is included at a concentration range of about 0.01% by weight to about 10.0% by weight.

[0069] In at least one embodiment of the method, the hemostatic composite particles composition comprises a further hemostatic agent such as collagen, chitosan, or tranexamic acid. In at least one embodiment, the hemostatic composite particles composition comprises at least one antibiotic or antimicrobial, such as ciprofloxacin, tobramycin, doxycycline, vancomycin, gentamicin, polyhexamethylene biguanide, minocycline, ceftriaxone, trovafloxacin, or silver sulfadiazine. In at least one embodiment, the hemostatic composite particles composition comprises at least one agent to reduce inflammation, such as corticosteroids, dexamethasone, betamethasone, methylprednisone, or triamcinolone. In at least one embodiment, the hemostatic composite particles composition comprises a combination of at least one antibiotic and at least one agent to reduce inflammation, such as a combination of ciprofloxacin and dexamethasone. By combining antimicrobials with anti-inflammatory agents, the hemostatic matrices address additional secondary injury pathways simultaneously while providing hemostasis.

[0070] In at least one embodiment, the hemostatic compositions comprise adsorbent composite polymer particles manufactured from lyophilized polymer particles of alpha hydroxy methacrylated polymers, such as particles having hydroxy-terminated methacrylate monomers, such as 2 -hydroxy ethylmethacrylate (HEMA) and / or 2-hydroxypropylmethacrylate (HPMA), from which poly-2-hydroxyethyl-methacrylate (pHEMA) and poly-2-hydroxypropyl- methacrylate (pHPMA) adsorbent composite particles are prepared and marketed as Altrazeal® transforming powder (Altrazeal Life Sciences Inc., Addison, Texas, USA). See, e.g., U.S. Patents No. 7,910,135, No. 7,811,605, No. 7,351,430. Additional adsorbent polymer particles may be prepared using 2-alkenoic acid, a hydroxy (2C-4C) alkyl 2-alkenoate, dihydroxy (2C- 4C) alkyl 2-alkenoate, hydroxy (2C-4C) alkoxy (2C-4C) alkyl 2-alkenoate, (1C-4C) alkoxy (2C- 4C) alkoxy (2C-4C) alkyl 2-alkenoate, or vicinyl epoxy (1C-4C) alkyl 2-alkenoate monomers. Selection and ratios of monomers can be tuned to adjust swelling, tensile strength, and drug release kinetics for specific neurosurgical indications. Generally, suitable polymer particles are prepared by polymerizing an effective amount of a monomer or two or more monomers of 2- alkenoic acid, hydroxy (2C-4C) alkyl 2-alkenoate, dihydroxy (2C-4C) alkyl 2-alkenoate,Docket No. 89380.0008\WG hydroxy (2C-4C) alkoxy (2C-4C) alkyl 2-alkenoate, (1C-4C) alkoxy (2C-4C) alkoxy (2C-4C) alkyl 2-alkenoate orvicinyl epoxy (1C-4C) alkyl 2-alkenoate with a polar liquid, or a mixture of two or more miscible liquids at least one of which is polar, and, optionally, from about 0.01 to about 0.1 percent (w / w) of surfactant to produce a suspension of a plurality of polymeric particles, then (if warranted for a specific formulation) lyophilizing the mixture. Such powders may be composed of ratios of poly-a-hydroxy olefinic methacrylate polymers formed as suspensions, that can be one component or mixed components, purified, and freeze dried. These materials are selected to ensure that the transformation occurs from a shape-conforming state to a shape-retentive state when the material contacts blood, body fluid, or aqueous solutions of physiological pH and ionic strength. These polymers have a long history of safe biomedical use. These materials may further incorporate at least one pharmaceutical agent. In at least one embodiment of treatment, the ultimate shape-retentive states are biocompatible and not quickly biodegradable - thus retaining their shape after aggregation and functioning as removable, biocompatible devices.

[0071] In at least one embodiment, the hemostatic compositions comprising composite particles further comprise an additional hemostatic agent. Examples of hemostatic agents that may be incorporated into the present embodiments include Tranexamic acid, chitosan or collagen or other powdered clotting agents. More specifically, for example, chitosan, analogs and derivatives thereof can also be added. Chitosan is a (poly (b-(l,4)-2-amino-2-deoxy-D- glucopyranose), a natural cationic glycosaminoglycan, has been used for tissue healing applications because of its excellent biocompatibility and mucoadhesive characteristics. Reports show that chitosan, when fabricated into beads, gels, sponges, or microcarriers, exhibits pH- sensitive swelling and drug release by diffusion through its porous structure. See, e.g., (Shu & Zhu, 233 Inf 1 J. Pharma. 217 (2002). Additionally, chitosan is a glycosaminoglycan (GAG) having natural ability to interact with host cells, and also similar to the integral component of extracellular matrix (ECM). See Agnihotri et al., 100 J. Control Release 5-28 (2004); Berger et al., 57 Eur. J. Pharma. Biopharm. 19 (2004). Collagen, and analogs and derivatives thereof, can also be included in the compositions provided herein as an additional hemostatic agent. Collagen is the major extracellular matrix (ECM) component present in interstitial tissues, providing approximately 30% of all ECM proteins. It is the prototypic substrate for immune defense and tissue repair. See, e.g., Brett, 20 Wounds 347 (2008); Chattopadhyay & Raines, 101 Biopolymers 821 (2014). TXA is a potent antifibrinolytic synthetic derivative of lysine. It has been indicated orally for the treatment of fibrinolysis disorders including cyclic heavy menstrual bleeding in premenopausal females. Intravenously, TXA is used for short periods to prevent and decrease bleeding in dental procedures in individuals with hemophilia as well as to help reduceDocket No. 89380.0008\WO swelling associated with hereditary angioedema. The high potency of TXA is attributed to its tight binding of plasminogen at the strong and weak affinity receptor sites leading to the strong inhibition of the plasminogen activation to plasmin. Formation of the latter is necessary for the activation of the first complement protein (Cl) which is involved in edema development as documented in angioedema attacks. Importantly, the binding to the high affinity receptors of plasminogen competes and prevents binding of plasminogen to fibrin which is a required interaction for fibrinolysis and dissolution of fibrin. As shown herein, combining chitosan or TXA with the composite particles resulted in synergistic clotting activity.

[0072] Regarding preparation of composite polymer particles, general polymer synthesis may be performed by dissolving monomer in purified water or other pharmaceutically acceptable polar solvent (e.g., ethanol) to provide a solution. Typically, the monomer concentration may be between about 1.5% and about 4%, such as 2.6% in the solution prior to polymerization. The following (Table 1) hydroxyl-terminated methacrylate monomers and ratios by percentage of the above monomer concentrations in solution can be combined to make polymer particles through free radical initiation. These ratios can be adjusted to change the desired physical properties (e.g., time to aggregation, device strength, sustained release characteristic) of the composite particles.Docket No. 89380.0008\WO

[0073] Further, within the polymers and copolymers noted above, it is further possible to combine particles of the polymers provided above at ratios (ranging from 100% polymer “A” to 100% polymer “B”), such that the polymer(s) would be combined so that the total percentage of polymer remains at about 50% to about 80%, but the formulation is a mixture of polymer particles. This results in a uniform distribution of two different kinds of polymer particles in a suspension, which results in the same distribution within a composite particles composition. The ratios in Table 2 provide representative examples of polymer particle ratio compositions that can be designed for desired characteristics such as strength, hydration, aggregation, or sustained / controlled release of active agents. These ratios are illustrative and not limiting, and other combinations may be used to achieve desired properties.Docket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WODocket No. 89380.0008\WO

[0074] As noted, the hemostatic composite particles compositions described herein may include at least one pharmaceutical agent for sustained release thereof. The rate of sustained release can be modified by changing the composition of the formulation (e.g., adjust polymer, particle, excipient, active) of the materials to provide a device tuned for different release profiles within a desired therapeutic range.Docket No. 89380.0008\WGEXAMPLESExample 1. Polymer particles for use in shape-transforming devices for hemorrhagic control

[0075] An example of particles suitable for use in manufacture of materials comprising adsorbent composite particles as described herein are particles commercially available as Altrazeal® Transforming Powder Dressing (available from Altrazeal Life Sciences, Inc., Addison, Texas, USA). These particles are sterile, odorless, crystalline, white powder composed of a mixture of lyophilized poly-2-hydroxyethyl-methacrylate (pHEMA) and poly-2 - hydroxypropyl-methacrylate (pHPMA) particles combined in a ratio of 85: 15. A description of the processes for preparing such lyophilized particles is provided in U.S. Patent No. 7,811,605. Briefly, pHEMA and pHPMA suspensions are prepared separately by the following free radical polymerization process: pHEMA suspension is prepared by mixing pure HEMA monomer with purified water containing a surfactant, then heating the mixture to a specified temperature. The addition of reaction initiator initiates the pHEMA polymerization, which is quenched using a specific process. pHPMA synthesis progresses similarly by replacing the HEMA monomer with HPMA monomer. After both polymer suspensions are prepared, the percentage of solid contents of both suspensions are measured and the total suspended solids are calculated for each providing a known range of solids in pHEMA and pHPMA suspensions. The solids are mixed to form a suspension with 85: 15 (w / w) ratio. The 85: 15 suspension is purified by tangential flow filtration (TFF) to remove unreacted monomer and exchange the surfactant with biocompatible known surfactant solution. After filtration and concentration, the suspension (TPD suspension) is poured into trays and placed into a freeze drier system for lyophilization. Lyophilization results in a cake of the suspension particles which, after sifting, yields a fine powder of known size ranges. Such particles may also be mixed with at least one pharmaceutical agent prior to the lyophilization process, be dry-mixed with at least one pharmaceutical agent after lyophilization, or remain as therapeutic / drug-free powders for on-demand mixing with at least one pharmaceutical agent at the point of care.

[0076] Copolymer particles comprising pHEMA and pHPMA may be synthesized using HEMA monomer and HPMA monomer. Table 3 shows the relative masses and mmol of monomers added to 150 mL bottles.Docket No. 89380.0008\WO

[0077] The above polymer particles are collectively called “polymer particles” and may be in suspension form or be lyophilized form. These represent the form of polymers that remain stable and useful in the shape-transforming composite particles composition systems described herein.Example 2. Hemostasis with Composite Particles

[0078] A perfusion funnel model was constructed with fresh bovine blood. Composite particles (0.3-0.5 g) were applied to the base and 21 g blood introduced. Flowthrough was measured for 1 minute. Composite particles prevented >95% of blood passage and formed a spongy, stable clot. Results are shown in Table 4.Example 3. Synergy with Hemostatic Agents

[0079] Composite particles (0.1 g) were blended with 1% mushroom-derived chitosan or tranexamic acid (TXA) and tested in the funnel model as described in Example 2. Results are shown in Table 5.Docket No. 89380.0008\WO

[0080] In compositions comprising both composite particles and chitosan or TXA, complete hemostasis was achieved within 1 minute with 0% flowthrough. In contrast, chitosan or TXA alone permitted 20%-68% bleed-through.Example 4. Comparison with QuickClot® Gauze

[0081] QuickClot Combat Gauze® hemostatic dressing with kaolin technology, was tested under identical conditions. A single layer of the gauze product allowed 45% flowthrough. Four stacked layers of product were required for full occlusion. By comparison, 0.4 g of composite particles achieved 0% flowthrough in one application. Results of this analysis are shown in Table 6.Example 5. In vitro hemostasis testing

[0082] In many settings, trauma is typically accompanied by bleeding that must be stopped. An ideal device for treating such injuries would have the capability of inducing the clotting resulting in a stable clot. Shape transforming devices comprising composite particles in powder preparations, with or without added hemostatic pharmaceutical agent(s), were tested in models designed to mimic bleeding wounds.

[0083] Regarding an example hemostatic agent, tranexamic acid (TXA) is a synthetic derivative of the amino acid lysine and is a common active pharmaceutical agent employed in surgical situations to control bleeding with clotting. An in vitro test was developed to show clotting of porcine blood with composite particles and composite particle compositions comprising TXA, prepared by either dry-blending or liquid aggregation. Following transformation to a shape-retentive state, blood was added to a device and allowed to clot for 1 minute. Following clotting, the clot and device were submerged in saline and assessed for the level of uncoagulated blood qualitatively leaking into the saline from the clot / device. Table 7 shows the results of these in vitro tests.Docket No. 89380.0008\WO

[0084] A further experiment assessed in vitro hemostasis using mass. More specifically, a study of shape transforming adsorbent composite particles devices combined with different clotting agents was performed using a gravimetric analysis of blood moving through a Buchner funnel and the ability of a clotting agent to form a clot and arrest the blood flow over time. A pair of filter papers were soaked in blood and blotted to remove drops of blood. The pair of filter papers were layered in the Buchner funnel (BF). Composite particles preparations were weighed and added to the top of the first filter paper quickly and the BF was tapped to arrange the transforming powder preparation in a uniform layer. The second filter paper was placed on top of the layer of transforming powder. A sample volume of blood was measured by mass. A tared beaker was placed beneath the BF. A timer was started at the timet the full volume of blood was poured into the BF. At 60 seconds the tared beaker was removed and weighed. The results are shown in Table 8.

[0085] The data in Table 8 show that composite particles formed a clot that prevented flowthrough of 99% of a mass of blood roughly 300% larger than the initial mass of composite particles. The composite particles formed an aggregate that was 32% composite particles and 68% moisture with isotonic liquids, however with clotting, the composite particles formed a spongy clot that halted the movement of blood with a mass of roughly 21 grams through a set ofDocket No. 89380.0008\WG pores where 90% of the blood would normally flow through freely. Lower masses of composite particles, e.g., 0.1 and 0.2 grams, in the funnel were very thin layers of the composite particles powder and likely did not form a complete aggregate with uniform interaction with the large volume of blood in this assay.

[0086] The in vitro blood coagulation testing was repeated using preparations of composite particles and chitosan from different sources. In one experiment, composite particles was combined with mushroom-derived chitosan to produce mixtures comprising from 0.05% to 5% (wt) mushroom-derived chitosan. The mixtures were formed by weighing composite particles and chitosan components and then mixing them by shaking in a centrifuge tube. A pair of filter papers were soaked in blood and blotted to remove drops of blood, composite parti cles- mushroom-derived chitosan preparations were weighed and added to the top of the first filter paper quickly and the BF was tapped to arrange the preparation in a uniform layer. The second filter paper was then placed on top of the layer of composite particles-mushroom-derived chitosan preparation. A volume of blood was weighed. A tared beaker was placed beneath the BF. A timer was started when the full volume of blood was poured into the BF. At 60 seconds the tared beaker was removed and weighed. Table 9 shows the results of this experiment.

[0087] During testing, the composite particles / clotting agent preparation formed immediate spongy masses of clots. When composite particles (alone) was tested at a very low mass (0.1 grams in the BF), as shown in Table 8, roughly 5% of the mass of blood was able to flow through the BF. With the addition of only 1% clotting agent to the this low quantity of composite particles, however, as shown in the last row of Table 9, the combination was able to stop 100% of blood from flowing through the BF in one minute even at the low mass of 0.1 g composite particles. This is surprising and indicates a synergistic effect of the composite particles / clotting agent combination.

[0088] In a further experiment, composite particles were combined with shellfish- derived chitosan to produce mixtures comprising from 0.05% to 5% (wt) shellfish-derivedDocket No. 89380.0008\WO chitosan. The mixtures were formed by weighing composite particles and chitosan and then mixing them by shaking in a centrifuge tube. A pair of filter papers were soaked in blood and blotted to remove drops of blood, composite particles-shellfish-derived chitosan preparations were weighed and added to the top of the first filter paper quickly and the BF was tapped to arrange the preparation in a uniform layer. The second filter paper was then placed on top of the layer of composite particles-shellfish-derived chitosan preparation. A volume of blood was weighed. A tared beaker was placed beneath the BF. A timer was started when the full volume of blood was poured into the BF. At 60 seconds, the tared beaker was removed and weighed. Table 10 shows the results of this experiment.

[0089] During testing, the composite particles / clotting agent preparation formed immediate spongy masses of clots. When composite particles was tested at a very low mass (0.1 grams composite particles in the BF), as shown in Table 8, roughly 5% of the mass of blood was able to flow through the BF. With the addition of the 1% clotting agent to the composite particles, the combination was able to stop 100% of blood from flowing through the BF in one minute. The last row of Table 10 shows that the combination of composite particles / clotting agent provides a synergistic effect in this preclinical model.

[0090] The in vitro coagulation experiment was repeated using preparations comprising shape transforming adsorbent composite particles and TXA. Composite particles were combined with TXA to produce preparations ranging from 0.05% to 5% (wt) TXA. The preparations were formed by weighing composite particles and TXA components and then mixing them by shaking in a centrifuge tube. A pair of filter papers were soaked in blood and blotted to remove drops of blood. Each composite particles-TXA preparation was weighed and added to the top of the first filter paper quickly and the BF was tapped to arrange the composite particles-TXA preparation in a uniform layer. The second filter paper was placed on top of the layer of composite particles- TXA preparation. A volume of blood was measured by mass. A tared beaker was placed beneath the BF. A timer was started at the time that the full volume of blood was poured into the BF. AtDocket No. 89380.0008\WG60 seconds, the tared beaker was removed and weighed. Table 13 shows results from the evaluation of the composite particles -TXA preparations in this in vitro test.

[0091] During testing, the composite particles / TXA preparations formed immediate spongy masses of clots. When composite particles was tested at a very low mass (0.1 grams composite particles in the BF), as shown in Table 8, roughly 5% of the mass of blood was able to flow through the BF. With the addition of the 1% clotting agent to the composite particles , however, the combination acted synergistically and was able to stop 100% of blood from flowing through the BF in one minute, as shown in the last row of Table 11.

[0092] To confirm the critical role of the composite particles in these experiments, the ability of each clotting agent alone, without inclusion in composite particles, was tested as above. The results indicated that in all cases the clotting agents allowed at least 20% of the blood to flow through the funnel even when using a mass equivalent to the composite particles material.

[0093] These experiments demonstrate that a preparation comprising a mixture of composite particles with a clotting agent has superior capability of stopping gravity-fed blood flow through a perforated surface, which can be extended as evidence for clotting in many presentations of bleeding. The clotting agent alone is inferior to the combination of composite particles with the clotting agent. With clotting agent alone, the blood does not appear to come in contact uniformly with the surfaces of the agent. The effect of superior clotting by the sustained release composite particles / clotting agent device appears to occur because of the combined aggregation and exposure of the blood to a uniform mixture of clotting agent. Indeed, the efficacy of the lowest amount of composite particles (0.1 g) combined with only 1% clotting agent shows that the composite particles provides synergistic coagulation activity.Docket No. 89380.0008\WOExample 6. Application to wound therapy

[0094] In general, wound healing is a dynamic interactive cascade of events involving chemical mediators, extracellular matrix and various cell types. Acute wounds follow a healing pattern which involves synchronized overlapping phases of coagulation, inflammation, and repair which consists of proliferation / granulation and matrix formation. An imbalance in the healing events causes an impairment in the healing process resulting in conversion of acute to chronic state. Chronic wounds result from complex and multiple intriguing factors and no single primary factor contributes to impaired wound healing. There is a large body of literature characterizing mechanistic insights leading to acute and chronic wound healing states. Despite this, the cellular and molecular mechanisms involved during wound healing are still not fully understood. Nonetheless, the key factors leading to impaired healing is due to the imbalance in inflammatory cytokines (e.g. IL-6, IL-ip, and TNF-a) and matrix remodeling enzymes (matrix metalloproteinases (MMP)), which are restored to physiological levels in the acute healing process. Another compounding clinical problem during healing is pain. Though pain is a common manifestation in both acute and chronic wounds, acute wound pain is perceived for a shorter duration, whereas in chronic wounds it remains persistent. Wound healing is a complex process requiring a multidimensional treatment approach and is complicated substantially by the risk of infection, blood loss and aggravated systemic immune responses experienced during traumatic injuries.

[0095] Wound healing can be enhanced by the early application of a multi-functional device that is easy to apply, portable, and contains requisite elements to treat complex injuries with multi-faceted needs. This may require a device(s) that can provide hemostatic properties, antimicrobial properties, and provides an environment that decreases the inflammatory response by signaling a proliferative rather than inflammatory response. Such devices should be easy to use at the point of injury, biocompatible, and remain non-toxic and non-sensitizing overextended periods of time while bringing comfort to the patient by providing pain relief and unrestricted movement. Additionally, the device should be capable of delivering active ingredients, sometimes for extended periods of time, so that their efficacy is maintained in cases of prolonged need.

[0096] Animal studies are conducted in compliance with the Animal Welfare Act, the implementing Animal Welfare regulations, or the principles of the Guide for the Care and Use of Laboratory Animals, National Research Council, in accredited research facilities such as accredited by, for example “AAALAC International.”

[0097] For antibiotic and infection studies each preparation containing a dose (such as one of two doses (high and low)) of an antibiotic (such as gentamycin, doxycycline,Docket No. 89380.0008\WO vancomycin, or silver sulfadiazine), are tested for anti-microbial efficiency using an established porcine partial thickness infected wound model. Controls include a negative control (no treatment) and a positive control (e.g., silver containing standard of care material, e.g., Silverlon® from Cura Surgical, Geneva, Ill. USA). For example, reproducible 1 cm2excision wounds (10 mm punch) are infected with either Pseudomonas aeruginosa or methicillin- resistant Staphylococcus aureus (MRS A). On day 1, forty -four wounds are created, and experimental conditions are tested. Under anesthesia, up to 10 mL blood may be drawn via percutaneous stick of the vena cava in the neck region periodically (for example, per day on days 0, 1, 3, 7) for CBC and biochemistry. At a suitable time point (such as on day 3), individual biopsies for each experimental group are obtained and reapplication of all experimental materials are performed. Individual biopsies are obtained again thereafter (such as on day 7). Animals are humanly euthanized. Primary endpoints may include, for example, reduction of bacterial load on day 3, as defined by a 103reduction from initial inoculum, (reduction to 1 x 103CFU / gram of tissue or below in bacterial load); or a static level (minimum desirable) via biopsy count of < U K)5CFU / gram of tissue. Secondary endpoints may include safety and subjective observation of any adverse events in the wounds. Such studies may be repeated and extended to 14 days for the most efficacious preparations.

[0098] As an example hemostatic screening, partial thickness wounds (1 cm2) are treated in experimental groups. Each group will have wounds for pharmaceutic agents (e.g., collagen, TXA low, TXA high, or chitosan), a negative control (no treatment), and a positive control (e.g., QuickClot®). An example 7-day study follows the infection study protocol with respect to biopsies at day 3 and day 7 (sacrifice). The primary endpoints may include clotting time and clot strength; the secondary endpoint may include safety, subjective observation of any adverse events in the wounds, and wound closure. Kinetics of blood clotting on the surface of the wound may be a difficult to measure, but the residual plasmin activity within the wound may be assessed using a modified fibrin plate method. The efficiency of agents (e.g., chitosan, collagen, TXA) in the wound dressing to affect plasminogen conversion to plasmin may be semi- quantitatively assessed using the modified fibrin plate method. This study may also be repeated and extended to 14 days for the most efficacious formulations.Industrial Applicability

[0099] The invention provides hemostatic compositions and methods applicable to human and veterinary medicine, including trauma care, elective surgery, interventional procedures, emergency medicine, and battlefield care. The compositions can be manufactured at scale, sterilized, stored at room temperature, and deployed in both civilian and military systems.Docket No. 89380.0008\WO

[0100] It is to be understood that the disclosure has been described in conjunction with the above embodiments, that the preceding description and examples are intended to illustrate and not limit the scope of the disclosure. Other aspects, advantages, and modifications within the scope of the disclosure will be apparent to those skilled in the art to which the disclosure pertains.

Claims

Docket No. 89380.0008\WOCLAIMSWe claim:

1. A composition comprising composite polymer particles, wherein the composition adsorbs blood and induces hemostasis at a bleeding site.

2. The composition of claim 1, wherein the composition persists at the bleeding site as a conforming protective layer after hemostasis.

3. The composition of claim 1, wherein the composition does not induce an exothermic reaction upon contact with blood or bodily fluids.

4. The composition of claim 1, wherein the composite particles comprise poly(2- hydroxyethyl methacrylate), poly(2-hydroxypropyl methacrylate), or combinations thereof.

5. The composition of claim 1, further comprising at least one hemostatic agent selected from chitosan, tranexamic acid, thrombin, fibrin, collagen, gelatin, alginate, kaolin, zeolite, or combinations thereof.

6. The composition of claim 1, wherein the hemostatic agent is 0.05% to 10% by weight.

7. The composition of claim 1, wherein the hemostatic agent is chitosan selected from mushroom-derived, shellfish-derived, or synthetic chitosan.

8. The composition of claim 1, wherein the hemostatic agent is tranexamic acid at 0.1% to 10% by weight.

9. The composition of claim 1, wherein the composition reduces blood flow >90% within 60 seconds.

10. The composition of claim 1, wherein the particles entrap red blood cells, platelets, and serum proteins.

11. A method of inducing hemostasis comprising applying the composition of claim 1 to a bleeding site, wherein the bleeding is selected from diffuse oozing, surgical bleeding, mucosal bleeding, organ surface bleeding, fragile tissue bleeding, chronic wound bleeding, or traumatic bleeding.

12. The method of claim 11, wherein the bleeding occurs at an incision or excision site selected from skin incisions, laparoscopic port sites, vascular access sites, biopsy sites, tumor excisions, or tissue harvest sites.

13. The method of claim 11, wherein the bleeding occurs in grafting procedures selected from skin graft donor sites, recipient beds, bone marrow harvest sites, vascular grafts, orthopedic grafts, or organ transplant sites, wherein the composition both induces hemostasis and persists as a protective layer at the graft site.

14. The method of claim 11, wherein the bleeding occurs at biopsy or puncture sites including liver biopsy, kidney biopsy, bone marrow aspiration, or catheter access sites.Docket No. 89380.0008\WG15. The method of claim 11, wherein the bleeding occurs during dental or oral and maxillofacial procedures including tooth extraction, periodontal surgery, or jaw reconstruction.

16. The method of claim 11, wherein the bleeding occurs during cosmetic and reconstructive procedures including flap surgery, skin excision, burn excision and debridement, cosmetic grafting, or hair transplantation donor sites.

17. The method of claim 11, wherein the bleeding occurs during obstetric, gynecologic, or urologic procedures such as cervical conization, prostate resection, prostate biopsy, or nephrectomy.

18. The method of claim 11, wherein the bleeding occurs during endoscopic, laparoscopic, or interventional radiology procedures including polypectomy, endoscopic mucosal resection, or vascular catheter access sites.

19. The method of claim 11, wherein the composition remains in situ as a conforming protective layer after hemostasis is achieved.

20. The method of claim 11, wherein the protective layer reduces risk of re-bleeding caused by friction, shear, or fragile elderly skin.

21. The method of claim 11, wherein the protective layer supports extended wound care for at least 24 hours without removal.

22. The method of claim 11, wherein the subject is receiving anticoagulant or antiplatelet therapy.

23. The method of claim 11, wherein the bleeding site is a surgical site selected from thoracic, cardiac, orthopedic, neurosurgical, vascular, dental, or gynecologic procedures.

24. The method of claim 11, wherein the bleeding site is a mucosal site selected from nasal, gastrointestinal, or oral mucosa.

25. The method of claim 11, wherein the bleeding site is ophthalmic and selected from conjunctival, scleral, orbital, or periocular sites.

26. The method of claim 11, wherein the bleeding site is an organ surface selected from hepatic, splenic, renal, peritoneal, pleural, or bone marrow surfaces.

27. The method of claim 11, wherein the bleeding site is abdominal or retroperitoneal, such as pancreatic, renal, or adrenal sites.

28. The method of claim 11, wherein the bleeding is traumatic and selected from lacerations, blunt trauma, penetrating wounds, gunshot wounds, or blast wounds.

29. The method of claim 11, wherein the bleeding occurs in fragile tissues including graft sites, friable tumors, or fragile elderly skin.

30. The method of claim 11, wherein the composition is contraindicated for intravascular or confined space use.Docket No. 89380.0008\WG31. A hemostatic kit comprising: (a) a sterile package containing the composition of claim 1; and (b) an applicator, gauze, sponge, mesh, or spray substrate for delivering said composition to a bleeding site.

32. The kit of claim 31, wherein the substrate is gauze or sponge pre-impregnated with the composite particles.

33. The kit of claim 31, wherein the composition is contained in a sachet, blister, syringe, or spray applicator.

34. The kit of claim 31, wherein the kit is configured for military, prehospital, surgical, or veterinary use.

35. The kit of claim 31, wherein the composite particles are prepared by dry blending with one or more hemostatic powders.

36. The kit of claim 31, wherein the kit further comprises a liquid hemostatic agent packaged separately, the liquid agent being applied to the composite particles to induce aggregation and hemostasis.

37. The kit of claim 31, wherein the kit comprises at least two separate dry powders configured to be combined or dry blended at the site of use immediately prior to application.

38. A method of enhancing efficiency of a hemostatic agent by combining it with the composition of claim 1, wherein the combination achieves faster hemostasis than the agent alone.

39. The method of claim 38, wherein the agent is thrombin, fibrin, or collagen.

40. The composition of claim 1, wherein the composition is non-exothermic upon fluid adsorption.

41. A composition of polymer particles comprising an adsorbent blend of 60% to about 90% (w / w) of a preparation comprising poly-2-hydroxyethyl-methacrylate (pHEMA) and 40 to 10% poly-2-hydroxypropylmethacrylate (pHPMA), wherein the polymer particles are present as flakes and when the polymer flakes come in contact with blood from an arterial or venous injury the flakes will adsorb blood and aggregate to form an intact polymer matrix with trapped blood.

42. The composition of polymer particles of claim 41, wherein the adsorption of blood occurs through a gradient moving from the site of contact between the polymer particles and blood through the polymer particles with adsorption of the blood and its components and the blood is retained within and between the swollen and aggregated polymer particles at a percentage of moisture between 50 and 95% liquid by mass at steady state.

43. The composition of polymer particles of claim 41, further comprising adsorbed blood, wherein blood cells are trapped in the aggregated mass and form a clot with the initiation and completion of the biological clotting cascade.Docket No. 89380.0008\WO44. The composition of polymer particles of claim 41, further comprising adsorbed blood, wherein the clotting cascade occurs within the first 5 seconds after adsorption of blood and aggregation of the polymer particles.

45. The composition of polymer particles of claim 41, further comprising adsorbed blood, wherein the cellular components of clotting are released so that additional blood not adsorbed by the aggregated polymer particles interacts with the released cellular components of clotting and forms a clot on and around the surface of the aggregated polymer particles and the incorporated clotted and clotting blood.

46. The composition of polymer particles of claim 41, which have been blended with a hemostatic agent so that the agent is uniformly blended within the polymer particles47. The uniform blended composition of blended polymer particles and hemostat of claim 46, that is in the range of 1% to 50% hemostat by mass.

48. The composition of blended polymer particles and hemostat of claim 46, in which the blended powders when contacted with blood from an arterial or venous injury will adsorb blood and aggregate to form an intact polymer matrix with trapped blood.

49. The composition of polymer particles blended with hemostat of claim 46, in which the adsorption of blood occurs through a gradient moving from the site of contact between the polymer particles and blood through the polymer particles with adsorption of the blood and its components and the blood is retained within and between the swollen and aggregated polymer particles at a percentage of moisture between 50% and 95% liquid by mass at steady state.

50. The composition of polymer particles and hemostat of claim 46, in which the movement of blood through the aggregating polymer particles causes interaction between cells within the blood and the hemostat material with a high mixing of blood with the hemostat not possible when a hemostat is pressed to blood.

51. The composition of polymer particles and hemostat of claim 46, in which blood is retained within and between the swollen and aggregated polymer particles and in contact with the hemostat and the total percentage of adsorbed blood is 50% and 95% liquid by mass at steady state.

52. The composition of polymer particles mixed with hemostat of claim 46, further comprising adsorbed blood in which the blood cells are trapped in the aggregated mass and interact with the hemostat to form a clot with the initiation and completion of the biological clotting cascade.

53. The composition of polymer particles mixed with hemostat with adsorbed blood of claim 52, in which the clotting cascade occurs within the first 5 seconds after adsorption of blood and aggregation of the polymer particles.Docket No. 89380.0008\WO54. The composition of polymer particles mixed with hemostat with adsorbed blood of claim 52, in which the cellular components of clotting are released so that additional blood not adsorbed by the aggregated polymer particles interacts with the released cellular components of clotting and forms a clot on and around the surface of the aggregated polymer particles and the incorporated clotted and clotting blood.

55. The composition of polymer particles and hemostat of claim 46, in which the hemostat is a chitin molecule.

56. The composition of polymer particles and hemostat of claim 46, in which the hemostat is a collagen molecule57. The composition of polymer particles and hemostat of claim 46, in which the hemostat is a zeolite anionic clay.

58. The composition of polymer particles and hemostat of claim 46, wherein the hemostat is tranexamic acid.

59. A method of treating a subject having a bleeding wound, comprising applying to the wound a shape-transforming composition comprising composite particles comprising poly-2- hydroxyethyl-methacrylate (pHEMA) and poly-2-hydroxypropylmethacrylate (pHPMA) adsorbent composite particles, wherein upon application to the bleeding wound the shapetransforming material transforms from a shape-conforming to a shape-retentive state, thereby inducing hemostasis.

60. The method of claim 59, wherein the shape-transforming adsorbent composite polymer particles as they hydrate and aggregate transforming from a shape-conforming powder to a shape-retentive material in which the total percent blood adsorbed of the final aggregate is 20% to 30% greater than the hydration percent of an isotonic solution such as saline.

61. The method of claim 59, wherein the shape-retentive state comprises a total percent blood adsorbed that is 20% to 30% greater than the hydration percent of an isotonic solution such as saline.

62. The method of claim 59, wherein the bleeding wound is caused by trauma, surgery, or other injury to veins or arteries.

63. The method of claim 59, wherein the preparation of pHEMA and pHPMA adsorbent composite particles is 85: 15 pHEMA:pHPMA (weight: weight).

64. The composition of claim 1, further comprising a backing layer, scaffold, or substrate selected from collagen sponges, gelatin foams, alginate sheets, polymer meshes, woven or nonwoven textiles, or biocompatible films, wherein the substrate enhances handling, placement, or stability at the bleeding site.Docket No. 89380.0008\WO65. The composition of claim 1, wherein the composite polymer particles are provided as a lyophilized solid cake, disc, film, or slab prior to comminution, said solid form being rehydratable to yield a conforming, shape-retentive hemostatic device.

66. The composition of claim 1, wherein the solid form is optionally impregnated with a hemostatic agent prior to lyophilization.

67. The composition of claim 1, wherein the material is configured to be applied in sequential or layered formats with additional hemostatic agents or bioactive layers to provide staged or synergistic clotting activity or additional drug carriers for staged or simultaneous therapeutic effects.

68. The composition of claim 1, further comprising a hemostatic agent selected from collagen, oxidized cellulose, starch-derived polysaccharides, dextran derivatives, polyglucosamine, polylysine-based polymers, synthetic peptide hemostats, or combinations thereof.

69. The composition of claim 1, wherein the aggregated material provides prolonged coverage of the bleeding site for at least 24 hours, 48 hours, or 7 days, reducing risk of rebleeding.

70. The composition of claim 1, wherein the aggregated material forms a barrier layer that is oxygen-permeable, moist, and flexible to protect fragile tissue post-hemostasis.

71. The kit of claim 31, wherein the composite particles are pre-loaded or adhered to a backing selected from gauze, sponge, mesh, foam, or textile pad.

72. The kit of claim 31, comprising at least two separate powders or solid forms configured to be applied sequentially or combined at the point of care.

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