Bulking hemostatic tablets containing oxidized regenerated cellulose

Abstract

The present invention relates to compressed hemostatic tablets or forms comprising a fibrous nonwoven oxidized cellulose (OC or ORC) multilayer material compressed into a shape-stable tablet, further comprising a calcium salt, and capable of rapidly expanding upon contact with blood or plasma. The compressed forms may further comprise multi-arm PEG-SG and are dimensionally stable, preferably in terms of length and width, for at least 48 hours after compression. In some embodiments, upon contact with blood, the compressed forms expand to 1.5 to 5 times their tablet length in 5 seconds, to 2 to 6 times their tablet length in 20 seconds, and to 3 to 6 times their tablet length in 5 minutes. The compressed forms are effective for hemostasis in heparinized blood.

Description

[Technical Field]

[0001] The present invention relates generally to swellable biodegradable hemostatic forms or tablets made from oxidized cellulose (OC) or oxidized regenerated cellulose (ORC) and various additives that improve the performance of compressed tablets for treating wounds. [Background technology]

[0002] In a wide variety of situations, animals, including humans, may experience bleeding due to wounds or during surgical procedures. In some situations, the bleeding is relatively mild, normal blood clotting functions, and simple first aid treatment is all that is required. In other situations, substantial bleeding may occur. These situations typically require specialized equipment and supplies, as well as personnel trained to administer appropriate rescue.

[0003] Conventional methods for achieving hemostasis include the use of surgical techniques, sutures, ligatures or clips, and energy-based coagulation or cauterization. When these conventional measures are ineffective or impractical, adjunctive hemostatic techniques and products are needed.

[0004] The selection of an appropriate method or product for controlling bleeding depends on many factors, including, but not limited to, the severity of the bleeding, the anatomical location of the bleeding source and the proximity of adjacent vital structures, whether the bleeding is from a discrete source or from a larger surface area, the visibility and precise identification of the bleeding source, and access to the bleeding source.

[0005] In an effort to address the above-mentioned problems, materials have been developed to control excessive bleeding. Topical absorbable hemostats (TAHs) are widely used in surgical applications. TAHs include products based on oxidized cellulose (OC), gelatin, collagen, chitin, chitosan, etc. To improve hemostatic performance, scaffolds based on the above-mentioned materials can be combined with biologically derived clotting factors such as thrombin and fibrinogen.

[0006] Due to their biodegradability, as well as their antiseptic and hemostatic properties, oxidized cellulose (OC)-based materials, such as oxidized regenerated cellulose (ORC), have long been used as topical hemostatic agents in a variety of surgical procedures, including neurosurgery, abdominal surgery, cardiovascular surgery, thoracic surgery, head and neck surgery, pelvic surgery, and skin and subcutaneous tissue procedures. Several methods are known for forming various types of hemostatic agents based on ORC materials, whether made as powders, woven fabrics, nonwoven fabrics, knitted fabrics, and other forms.

[0007] U.S. Patent Application Publication No. 2012 / 0101520 relates to an apparatus and method used to seal a vascular puncture site, particularly a puncture site resulting from a catheterization or other interventional procedure. The sealing device includes a sealing member and a tether. The sealing member occupies a space in an incision, puncture, or other wound and seals the space it occupies to prevent further blood flow. The tether is attached to the sealing member and provides the user with the ability to withdraw the sealing member when desired.

[0008] U.S. Pat. No. 8,518,064 generally relates to a method for anchoring an expandable biocompatible plug material to a blood vessel wall to form a fixed occlusive plug that blocks or reduces blood flow to a desired vascular target, such as tumor tissue or an artery supplying blood to a tumor.

[0009] U.S. patent application having Publication No. 2005 / 0287215 discloses a plurality of filled particles comprising interstitial pores, the interstitial pores having a pore volume and median pore diameter effective to provide improved absorption of physiological fluids or aqueous media when placed in contact with the physiological fluids or aqueous media compared to a plurality of unfilled particles of the same material, the particles being made of a biocompatible material and having an average diameter suitable for use in providing hemostasis to a site in a mammalian body in need thereof, a hemostatic composition comprising such a plurality of filled particles, methods of making such particles and compositions, and medical devices suitable for delivering and containing the hemostatic plurality of particles and / or compositions to a site in the body.

[0010] U.S. patent application having publication number 2014 / 0142523 discloses a self-expanding wound dressing including a first outer layer, a second outer layer, and a liquid-expandable layer disposed between the first and second outer layers, the liquid-expandable layer including a plurality of liquid-expandable articles held by a substrate, the plurality of liquid-expandable articles forming expanded articles upon contact with a liquid.

[0011] U.S. Patent No. 8,828,050 relates to a hemostatic composition comprising a plurality of liquid-expandable articles that can expand upon contact with a liquid. Suitable compositions include a plurality of liquid-expandable articles that may not be mechanically coupled to one another and thus can move independently of one another. The plurality of liquid-expandable articles may comprise a compressible material that allows for a high degree of expansion upon contact with a liquid.

[0012] U.S. Patent Application Publication No. 2007 / 0014862 discloses a hemostatic material comprising oxidized cellulose in the form of a compressible, moldable mass that can remain in a substantially compressed or molded form for placement on a bleeding site or within a wound gap. The oxidized cellulose may be pellets of nonwoven oxidized cellulose fiber strands or nonwoven cellulose fiber strands arranged in a woven or otherwise gauze or mesh. The pellets may be compressed before application to the wound, allowing them to expand and conform to the shape of the wound. The pellets may remain within the wound during wound healing, allowing them to be absorbed by the body's biological processes.

[0013] U.S. Patent Application Publication No. 2006 / 0078589 discloses a device for treating oral wounds that have gaps and are therefore too large to suture. The device is intended to fill the resulting wound and, upon contact with bleeding tissue, causes local hemostasis. The device remains in the wound and protects it during the healing process.

[0014] U.S. Patent Application Publication No. 2021 / 0038757(A1), entitled "Expandable Hemostat Composed Of Oxidixed Cellulose," discloses a biodegradable hemostatic matrix comprising oxidized cellulose (OC), wherein the OC comprises one or more sheets, and the matrix has (i) about 0.8 to about 1.2 gr / cm 3 and (ii) is capable of expanding to at least three times its original volume within four seconds upon contact with an aqueous solution at at least one temperature between 10 and 40°C.

[0015] U.S. Patent Application Publication No. 2008 / 0027365(A1), entitled "Hemostatic Device With Oxidized Cellulose Pad," discloses a device for promoting hemostasis, which includes oxidized cellulose in the form of a compressible, moldable mass that is formed into a sheet for placement over the bleeding site.

[0016] U.S. Patent No. 10,034,957, entitled "Compacted Hemostatic Cellulosic Aggregates," discloses a method for making a plurality of hemostatic aggregates, the method including: a) grinding a cellulose source material to form fibers; b) moistening the fibers to a moisture content of 11.0% to 20% by weight; c) roller compacting the fibers to form a hemostatic aggregate; d) sieving the hemostatic aggregate; e) dehumidifying the hemostatic aggregate to a moisture content of less than 5.5% as determined by loss on drying; and f) optionally placing the resulting hemostatic aggregate into a storage container or delivery device.

[0017] U.S. Patent No. 11,007,301, entitled "Hemostatic mixture of cellulose-based short and long fibers," discloses a method for producing a hemostatic composition, comprising the steps of: a) reducing the size of a cellulose-based material to form long fibers with a size distribution of D90 greater than 177 μm and D50 greater than 95 μm and fine fibers with a size distribution of D90 less than 177 μm and D50 less than 95 μm, and mixing the long fibers and fine fibers in ratios ranging from 5% to 25% w / w and 95% to 75% w / w, respectively, thereby obtaining a hemostatic fiber composition, wherein the size reduction is achieved by grinding; and b) optionally subjecting the hemostatic fiber composition obtained in step a) to further steps to obtain a hemostatic composition in the form of an aggregate, including: i) compressing the hemostatic fiber composition to obtain a compressed hemostatic fiber composition; and optionally, ii) reducing the size of the compressed composition.

[0018] U.S. Patent No. 8,815,832, entitled "Oxidized regenerated cellulose hemostatic powders and methods of making," discloses a hemostatic material comprising a ball-milled ORC powder containing particles having an average aspect ratio of about 1 to about 18, the powder having a density of at least 0.45 g / cm.3 a tap density of 0.01 to 0.15, an average particle size of 1.75 micrometers to 116 micrometers with a median diameter of 36 micrometers, and a flowability of at least 7.5 cm / sec.

[0019] U.S. Patent No. 5,823,983, entitled "Bandages comprising compressed cellulose," discloses a compression bandage comprising: (a) a bandage including: (i) a sanitary gauze layer applied to a wound; (ii) a treated compressed cellulose inner layer having particles covering the sanitary gauze layer; and (iii) an outer layer covering the sanitary gauze layer and the treated compressed cellulose inner layer, the outer layer having adhesive wings for applying the bandage to the wound and access holes drilled therethrough and through the compressed cellulose inner layer, whereby as blood from the wound is absorbed through the gauze layer, it saturates the compressed cellulose material, thereby expanding the cellulose layer against the sanitary gauze and outer layer, thereby applying active pressure to the wound.

[0020] U.S. Patent Application Publication No. 2010 / 0184968(A1), "Method For Preparing An Oxidized Cellulose Compress," discloses a method for preparing an oxidized cellulose compress, which comprises oxidizing a cellulosic compress with a hypohalite in the presence of an oxoammonium salt.

[0021] U.S. Patent Application Publication No. 2007 / 0014862(A1), entitled "Device for treating wound gaps," discloses a hemostatic material comprising oxidized cellulose in the form of a compressible and moldable mass that can remain in a substantially compressed or molded form for placement over a bleeding site or within a wound gap. Summary of the Invention [Problem to be solved by the invention]

[0022] However, because bleeding control is essential and important in surgical procedures to minimize blood loss, reduce postoperative complications, and shorten operating time in the operating room, improved hemostatic forms and materials that facilitate ease of application are needed, especially at hard-to-reach bleeding sites. [Means for solving the problem]

[0023] In some embodiments, the present invention relates to a compressed hemostatic tablet or form, the compressed hemostatic tablet or form comprising a fibrous nonwoven oxidized cellulose (OC or ORC) multilayer material compressed into a form-stable tablet, further comprising a calcium salt, the tablet being capable of rapid expansion upon contact with blood. The compressed form may further comprise multi-arm PEG-SG and is stable for at least 48 hours after compression. In some embodiments, upon contact with blood, the compressed form expands to 1.5 to 5 times its tablet length in 5 seconds, to 2-6 times its tablet length in 20 seconds, and to 3-6 times its tablet length in 5 minutes. The compressed form is effective for hemostasis in heparinized blood.

[0024] In other embodiments, the compressed foam is made by compressing a stack of nonwoven OC materials in the presence of a calcium salt solution in ethanol, followed by drying under vacuum to evaporate the ethanol. In some embodiments, the compressed foam is made by compressing a stack of nonwoven OC materials in the presence of a calcium salt solution in ethanol, followed by drying under vacuum to evaporate the ethanol, followed by contact with a solution of multi-arm PEG-SG in a volatile solvent and vacuum drying.

[0025] In another embodiment, a method of making a compressed form includes cutting multiple identical pieces of nonwoven OC material, arranging the multiple identical pieces of nonwoven OC material into a stack, adding a solution of calcium salt in ethanol to a compression die, compressing the stack to at least 4 compression levels, and drying the stack under elevated temperature and vacuum to evaporate substantially all of the ethanol and form a stable tablet.

[0026] In some embodiments, the method also includes the steps of absorbing a solution of multi-arm PEG-SG in a volatile solvent onto a tablet and vacuum drying the tablet, or spraying a solution of multi-arm PEG-SG in a volatile solvent onto a tablet and vacuum drying the tablet.

[0027] In some embodiments, a method of treating a wound is provided, comprising applying a compressed ORC form of the present invention onto and / or into a wound of a subject in need thereof. [Brief explanation of the drawings]

[0028] [Figure 1A] Photographs of the ORC compact forms in Table 2 taken after 5 minutes of contact and exposure to blood are shown. [Figure 1B] Photographs of the ORC compact forms in Table 2 taken after 5 minutes of contact and exposure to blood are shown. [Figure 1C] Photographs of the ORC compact forms in Table 2 taken after 5 minutes of contact and exposure to blood are shown. [Figure 1D] Photographs of the ORC compact forms in Table 2 taken after 5 minutes of contact and exposure to blood are shown. [Figure 2A] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 2B] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 2C] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 2D] 1 shows a schematic representation of a compressed tablet of the present invention. [Figure 2E] 1 shows a schematic representation of a compressed tablet of the present invention. [Figure 2F] 1 shows a schematic representation of a compressed tablet of the present invention. [Figure 3] A plot of compressive force (g) versus time (s) up to 11 seconds is shown, where regions of different types of deformation were identified. [Figure 4]1 shows a plot of compression force (g) versus time (s) up to 120 seconds for ORC tablets compressed without added water. Also shown is the tablet after swelling. [Figure 5] 1 shows a plot of compression force (g) versus time (s) up to about 120 seconds for tablets containing added water. Also shown is the tablet after it has been allowed to expand. [Figure 6] 1 shows a plot of compression force (g) versus time (s) up to about 120 seconds for tablets containing added water. Also shown is the tablet after it has been allowed to expand. [Figure 7] 1 shows a plot of compression force (g) versus time (s) up to about 120 seconds for tablets containing added water. [Figure 8A] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 8B] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 8C] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 8D] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 8E] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 8F] 1 shows a schematic diagram of a method for producing compressed ORC tablets of the present invention. [Figure 9A] 1 shows a plot of compression force (g) versus time (s) up to 120 seconds for ORC tablets made with ethanol. Also shown is the tablet after expansion. [Figure 9B] Shown is a 3 mm tablet made by adding ethanol to blood. [Figure 9C] Shown is a 3 mm tablet made by adding ethanol to blood. [Figure 10A] 1 shows a plot of compression force (g) versus time (s) up to 120 seconds for ORC tablets made with acetone. Also shown is the tablet after expansion. [Figure 10B] Shown is a 3 mm tablet made by adding acetone to blood. [Figure 10C]Shown is a 3 mm tablet made by adding acetone to blood. [Figure 11A] 1 shows a plot of compression force (g) versus time (s) up to 120 seconds for ORC tablets made with 10% CaCl solution in ethanol. Also shown is the tablet after expansion. [Figure 11B] Shown are the initial tablets and the tablets after reacting with blood and swelling in the blood after 5 minutes of blood contact. [Figure 11C] Shown are the initial tablets and the tablets after reacting with blood and swelling in the blood after 5 minutes of blood contact. [Figure 11D] Shown are the initial tablets and the tablets after reacting with blood and swelling in the blood after 5 minutes of blood contact. [Figure 11E] Shown are the initial 3mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11F] Shown are the initial 3mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11G] Shown are the initial 3mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11H] Shown are the initial 5mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11I] Shown are the initial 5mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11J] Shown are the initial 5mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11K] Shown are the initial 10mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11L] Shown are the initial 10mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 11M] Shown are the initial 10mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 12]1 shows the time required for compressed fibril ORC tablets made with ethanol (F-10Ca-Et) containing 10% CaCl to expand to 3.5 cm in length. [Figure 13] 1 shows the density of F-10Ca-Et tablets. [Figure 14] 1 shows the CaCl2 content in the tablet in g / cm3 of F-10Ca-Et tablets. [Figure 15A] 1 shows the results of testing 5 mm long compressed ORC tablets containing various amounts of added CaCl. [Figure 15B] Shown are the initial 5 mm tablet F-10Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 15C] Shown are the initial 5 mm tablet F-10Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 15D] Shown are the initial 5 mm tablet F-10Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 15E] Shown are the initial 5 mm F-20Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 15F] Shown are the initial 5 mm F-20Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 15G] Shown are the initial 5 mm F-20Ca-Et, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood. [Figure 16] The weight percent concentration of CaCl2 for 5 mm compressed tablets is shown. [Figure 17] 1 shows the density of F-10Ca-Et and F-20Ca-Et tablets. [Figure 18A] A comparative schematic of a snow layer (A) versus a fibril layer (B) before compression is shown. [Figure 18B] A comparative schematic of a snow layer (A) versus a fibril layer (B) before compression is shown. [Figure 18C] Shown are compressed tablets designated as Snow-C and Fibril-D. [Figure 18D] Shown are compressed tablets designated as Snow-C and Fibril-D. [Figure 18E] Tablets, Snow-E and Fibril-F swelled in blood. [Figure 18F] Tablets, Snow-E and Fibril-F swelled in blood. [Figure 19] % CaCl by weight of the final snow-compressed ORC tablets S-10Ca-Et at 3, 5, and 10 mm thicknesses. [Figure 20] The CaCl2 wt% of the final fibril-compressed ORC tablets F-10Ca-Et at 3, 5, and 10 mm thicknesses is shown. [Figure 21A] 1 shows the test results of tablets F-10Ca-Et-SGa prepared by the absorption method. [Figure 21B] 1 shows the test results of tablets F-10Ca-Et-SGa prepared by the absorption method. [Figure 22A] 1 shows the test results of tablet F-10 Ca-Et-SG prepared by the spray method. [Figure 22B] 1 shows the test results of tablet F-10 Ca-Et-SG prepared by the spray method. [Figure 22C] 1 shows the test results of tablet F-10 Ca-Et-SG prepared by the spray method. DETAILED DESCRIPTION OF THE INVENTION

[0029] The object of the present invention is to provide an expandable hemostatic tablet composition comprising oxidized cellulose (OC), more preferably oxidized regenerated cellulose (ORC) having a specific range of density, which can be highly expanded upon contact with body fluids and easily applied to the required site to achieve hemostasis, for example, in the case of a puncture wound or tissue gap. An advantage of the expandable compositions described herein is their ability to rapidly expand into an expanded form, which allows the expanded composition to rapidly fill the wound cavity and provide a nearly immediate hemostatic effect without the need for any external pressure or compression.

[0030] Further advantages associated with the present invention include ease of delivery in minimally invasive, laparoscopic, and / or robotic procedures due to the compact form of the hemostatic tablets of the present invention before expansion or swelling, improved positioning within the wound, improved tissue apposition, and better conformance to complex wound contours.

[0031] As described in more detail below, the compositions of the present disclosure can be applied to bleeding tissue and then, upon exposure to bodily fluids, rapidly expand to take the shape of the wound and assist in hemostasis. The compositions can remain at the wound site while degrading over time.

[0032] In some embodiments, the composition in its dry state remains in a substantially compressed or molded form prior to contacting or placing in or on blood or bodily fluids or aqueous media such as aqueous solutions, particularly at a bleeding site or wound.

[0033] See U.S. Patent Application Publication No. 2021 / 0038757(A1), "Expandable Hemostat Composed Of Oxidized Cellulose," co-authored by one of the present inventors. Material 0.785 cm 2 For a compaction pressure of 2 tons per minute, Table 2A in the reference shows a maximum swelling of 7.66 mL in saline for the Snow ORC matrix and 7.66 mL for the Fibril ORC matrix. Table 2B shows maximum swellings of 4.90, 6.86, and 7.32 mL for the Surgicel, Fibril, and Snow ORC matrices, respectively.

[0034] Example 1. Preparation of comparative samples The compact form expansion results of the '757 publication for expansion in saline were reproduced in this disclosure with the same materials and the same parameters of testing and compression with very similar maximum expansion coefficients, as shown below.

[0035] [Table 1]

[0036] As can be seen from Table 1, the comparative compacted forms produced in this study are virtually identical to the compacted forms of the '757 publication and exhibit very similar behavior in saline.

[0037] The materials mentioned above are SURGICEL® Original Absorbable Hemostat (loose knit ORC), SURGICEL® NU-KNIT® Absorbable Hemostat (tightly woven knit ORC), SURGICEL® FIBRILLAR™ Absorbable Hemostat (soft, lightweight, layered ORC), and SURGICEL® SNoW™ Absorbable Hemostat (structured nonwoven, needle-punched with interlocking fibers), all available from Ethicon, Inc.

[0038] Surgicel® Fibrils were introduced in 1996, offering surgeons a customizable nonwoven configuration. Surgicel® Fibrils can be separated into layers or pulled into tufts that rapidly conform and dissolve in tissue. The fourth member of the Surgicel® family, Surgicel® Snow™ Absorbable Hemostat (a Surgicel® structured nonwoven), was introduced in 2010. Surgicel® Snow™ is lightweight, drapeable, and capable of holding stitches. The nonwoven structure provides increased surface area, allowing the product to increase surface contact with the bleeding site, resulting in more efficient and faster hemostasis times—43% faster than Surgicel® Original. Surgicel® Snow™ was specifically designed for minimally invasive surgery, offering ease of use with laparoscopic tools and efficient product placement.

[0039] However, when the inventors tested the replica compact form of the '757 publication for expansion in blood, unexpectedly, no expansion was observed. Referring to Table 2, the inventors tested either the 10 mm diameter replica compact form replicating the '757 publication or the 0.785 cm diameter replica compact form in blood (5 mL of citrated butadiene blood in a 3.5 cm diameter Petri dish at 20°C). 2 Tablets compressed at 2 tonnes per tablet, and 0.785cm 2 Tablets of 6 mm diameter compressed at 0.72 tonnes per tablet were prepared and tested.

[0040] [Table 2]

[0041] 1A-1D show photographs of the ORC materials in Table 2, with the sidewall portion of the cylindrical tablet facing the blood, taken after 5 minutes of exposure and contact with blood. As can be seen, after 5 minutes of exposure, no or very little swelling is observed in all cases.

[0042] Example 2. Preparation of compressed ORC tablets Compressed ORC tablets of the present invention were made from fibril ORC material as follows. Referring to FIG. 2, a schematic diagram of the manufacturing process is shown. In the first step, 10 circular pieces (total weight 0.6 g) were cut from the fibrils using a 6 mm diameter punch (FIG. 2A). The cut fibrils were then transferred to a 6 mm diameter circular die (FIG. 2B). The 10 layers were then compressed to the desired final length (thickness), such as 10 mm, 5 mm, or 3 mm, at the desired pressure using a Texture Analyzer (Model: TA.XTplusC, Serial Number: 2P6Z11030-01-V003BFFC0) (FIG. 2C). The resulting compressed ORC tablets made from 10 individual fibril discs were then extruded from the die. For some modified compositions, various additives or binders can be added directly into the die. Figures 2D, 2E, and 2F show schematic diagrams of compressed tablets of the present invention produced by the above method, all of which have a diameter (D) of 6 mm and lengths (L) (or thickness or height) of 3 mm (Figure 2D), 5 mm (Figure 2E), and 10 mm (Figure 2F).

[0043] A plot of compression force (g) versus time (s) up to 11 seconds for a pure fibril-based compressed tablet without any additives is shown in Figure 3. In Figure 3, regions of different types of deformation are identified, with elastic deformation resulting in a 10-layer tablet thickness of 10 mm and plastic deformation at different force levels resulting in thicknesses of 5 mm and 3 mm.

[0044] Example 3. Fibrillar ORC tablets with added water Figure 4 shows a plot of compression force (g) versus time (s) for ORC tablets compressed without added water up to 120 seconds, where the compression stage takes approximately 11–12 seconds. The longer the time, the more tablet expansion is possible due to the lower stability of the compressed tablets. Tablet morphology obtained after expansion from compressed lengths (thicknesses) of 10, 5, and 3 mm, all containing the same amount of ORC, is shown. As can be seen, ORC tablets lack stability and spontaneously expand after compression, with the 3 mm thick or most compressed tablets showing the least expansion after compression.

[0045] Adding water at different levels to the 10-layer fibril structure before compression somewhat improved the stability of the compressed tablets. Water was added directly into the die already containing 10 layers of fibrils just before compression, and water addition was measured by the weight of the water added.

[0046] Figure 5 shows a plot of compression force (g) versus time (s) for tablets containing 5.95% water up to approximately 120 seconds, showing tablets that spontaneously expanded after two days, demonstrating the poor stability of compressed tablets at lengths or thicknesses of 5 and 10 mm. Tablet morphologies obtained after two days of expansion from compressed lengths (thicknesses) of 10, 5, and 3 mm are shown. As can be seen, tablets containing 5.95 wt% water compressed to a thickness or length of 3 mm at a maximum force of over 21,000 g maintained their shape when measured two days after compression, while tablets compressed at lower forces, such as 7,500 g or less, failed to maintain their shape. Figure 5 also shows a 3 mm tablet containing 5.95% water immersed in blood, which showed no or very limited expansion even after 5 minutes of blood contact.

[0047] Similarly, Figure 6 shows a plot of compression force (g) versus time (s) for tablets containing 8.68% water up to about 120 seconds, with the swollen tablets demonstrating poor stability of compressed tablets at lengths of 5 and 10 mm after two days. Tablet morphologies obtained after swelling from compressed lengths (thickness) of 10, 5, and 3 mm are shown. As can be seen, tablets containing 8.68 wt% water compressed to a thickness or length of 3 mm at a maximum force of over 21,000 g maintained their shape when measured two days after compression, while tablets compressed at lower forces, such as 7,500 g or less, failed to maintain their shape. Also shown in Figure 6 is a 3 mm tablet containing 8.68% water immersed in blood, which showed no or very limited swelling even after 5 minutes of blood contact.

[0048] Similarly, Figure 7 shows a plot of compression force (g) versus time (s) for tablets containing 13.23% water up to approximately 120 seconds, demonstrating the poor stability of tablets compressed to a 10 mm length. Tablet morphologies obtained after expansion from compression lengths (thickness) of 10, 5, and 3 mm are shown. As can be seen, tablets containing 13.23 wt.% water compressed to a 3 mm thickness or length with a maximum force of over 21,000 g and tablets compressed to a 5 mm thickness or length with a force of approximately 7,000 g maintained their shape when measured two days after compression. Tablets compressed at lower forces were unable to maintain their shape. Also shown in Figure 6 are 3 mm tablets containing 13.23% water immersed in blood and 5 mm tablets containing 13.23% water immersed in blood; both tablets showed no or very limited expansion, even after 5 minutes of blood contact.

[0049] The test results are shown in Table 3.

[0050] [Table 3]

[0051] The above data show that the presence of moisture and compression to a thickness of 3 mm results in stability, and that 13% water also results in stability for the 5 mm tablets, while the other samples are not stable. None of the tablets show rapid or significant swelling when exposed to blood.

[0052] Example 4. Solvent-added fibril ORC tablets Similar to the process described above, a schematic of the manufacturing method is shown in Figure 8. In the first step, a 6 mm punch was used to cut 10 circular pieces (total weight 0.6 g) from the fibrils (Figure 8A). The cut fibrils were then transferred to a 6 mm diameter circular die (Figure 8B). 1 mL of pure solvent (ethanol or acetone) was then added to the die and allowed to absorb by the fibril material (Figure 8C). The 10 layers were then compressed to the desired final length (thickness), such as 10 mm, 5 mm, or 3 mm, at the desired pressure as determined by the texture analyzer (Figure 8D), as described above. A bilayer plate was then used to clamp some dies with the compressed tablets inside (Figure 8E), and the tablets were held inside the dies by the compression piston. The entire die was then placed in a vacuum oven (Yamato Scientific Co., Ltd., Model: ADP300C, Serial Number: J3080178) equipped with a cold trap (Yamato Scientific Co., Ltd., Model: CA301, Serial Number: 63700976) at 70 °C and -0.08 MPa to dry for 3 h (Figure 8F) and evaporate the solvent. The resulting compressed ORC tablet, made from 10 individual discs of fibrils, was then extruded from the die.

[0053] Similar to the characterization of ORC tablets with added water described above, tablets made using solvents were also tested as follows. Figure 9A shows a plot of the compression force (g) versus time (s) for fibrillar ORC tablets made using ethanol up to 120 seconds. As shown, tablets made using ethanol at lower compression forces exhibit poor stability for tablets compressed to lengths or thicknesses of 5 and 10 mm. Tablet morphologies obtained after expansion from compressed lengths (thicknesses) of 10, 5, and 3 mm are shown. As can be seen, tablets compressed to a thickness or length of 3 mm at a maximum force of approximately 20,000 g maintained their shape when measured two days after compression, whereas 5 and 10 mm tablets compressed at lower forces, such as 7,500 g or less, failed to maintain their shape and spontaneously expanded.

[0054] Figures 9B and 9C show a 3 mm tablet made with ethanol in blood at the start of immersion and after 30 seconds, with no substantial swelling.

[0055] Figure 10A shows a plot of fibrillar ORC tablets made with acetone, showing compression force (g) versus time (s) up to 120 seconds. As shown, tablets made with acetone at lower compression forces exhibit poor stability for tablets compressed to lengths or thicknesses of 5 and 10 mm. Tablet morphologies obtained after expansion from compression lengths (thicknesses) of 10, 5, and 3 mm are shown. As can be seen, tablets compressed to a thickness or length of 3 mm at a maximum force of approximately 21,500 g maintained their shape when measured two days after compression, whereas tablets compressed at lower forces, such as 7,500 g or less, failed to maintain their shape and spontaneously expanded.

[0056] Figures 10B and 10C show a 3 mm tablet made with acetone in blood at the start of immersion and after 30 seconds, with no substantial swelling.

[0057] Even stable compressed ORC tablet forms made with solvents show virtually no swelling in the blood.

[0058] Example 5. Fibrillar ORC Tablets Made with CaCl and Ethanol Similar to the process described above, compressed ORC tablets of the present invention were made by adding various concentrations of CaCl2 in ethanol to the fibrils before compression. After transferring the fibrils to a 6 mm diameter circular die, 1 mL of ethanol containing varying amounts of CaCl2 was added directly to the die and allowed to absorb into the fibril material. Ten layers were then compressed to the desired final length (thickness), such as 10 mm, 5 mm, or 3 mm, at the desired pressure as determined by the texture analyzer, as described above. A bilayer plate was then used to clamp several dies with the compressed tablets inside, and the tablets were held inside the dies by a compression piston. The entire die was then placed in a vacuum oven at 70°C and -0.08 MPa for 3 hours to dry and evaporate the ethanol. The resulting compressed ORC tablets, made from 10 individual discs of fibrils and containing a fixed amount of added CaCl2, were then extruded from the die and tested.

[0059] 11A shows a plot of ORC tablets made with a 10% CaCl solution in ethanol, showing compression force (g) versus time (s) up to 120 seconds. Tablets made with ethanol and 10% CaCl showed good stability at all compression forces and all lengths or thicknesses after 2 days, as shown, indicating good stability of compressed tablets at lengths or thicknesses of 3, 5, and 10 mm.

[0060] Figures 11B-11D show the initial tablet and the tablets after reacting with blood and swelling in the blood after 5 minutes of contact with the blood: Figure 11B shows a 3 mm tablet, Figure 11C shows a 5 mm tablet, and Figure 11D shows a 10 mm tablet.

[0061] Figures 11E, 11F and 11G show the initial 3mm tablet, the tablet after 5 seconds in blood and the tablet after 20 seconds in blood, respectively.

[0062] Figures 11H, 11I and 11J show the initial 5mm tablet, the tablet after 5 seconds in blood and the tablet after 20 seconds in blood, respectively.

[0063] Figures 11K, 11L and 11M show the initial 10 mm tablet, the tablet after 5 seconds in the blood, and the tablet after 20 seconds in the blood, respectively.

[0064] The data show that the addition of various concentrations of CaCl in ethanol resulted in very rapid expansion of all compressed ORC tablets, with expansion occurring within 5 seconds, 20 seconds, and 5 minutes, as shown in Table 3A.

[0065] [Table 4]

[0066] The results show that all tablets, including those with lengths of 3, 5, and 10 mm, compressed at low, medium, and high compression forces, exhibit very significant and rapid expansion upon contact with blood. All compressed tablets reach an expansion length of at least half the initial length of the ORC stack before compression, for example, 50%, 60%, 75%, and 80% of the initial ORC stack before compression.

[0067] FIG. 12 shows the time required for compressed fibrillar ORC tablets made with ethanol containing 10% CaCl (F-10Ca-Et) to expand to a length of 3.5 cm, with the 3 mm tablets taking approximately 42 seconds, the 5 mm tablets taking 32 seconds, and the 10 mm tablets taking 31 seconds.

[0068] FIG. 13 shows the density of the F-10Ca-Et tablets.

[0069] Figure 14 shows the g / cm of F-10Ca-Et tablets. 3 The CaCl2 content in the tablets at 100 mg / kg is shown.

[0070] Table 4 shows comparative data testing compressed ORC tablets made with solvent and with the addition of CaCl. As can be seen in the table, the F-10Ca-Et compressed ORC tablets show superior performance at all compression levels and thicknesses for both stability and swelling in blood.

[0071] [Table 5]

[0072] Further testing was performed on various concentrations of CaCl in 5 mm fibril tablets made with ethanolic CaCl solutions, as follows: Figure 15A shows the results of testing 5 mm long compressed ORC tablets containing various amounts of added CaCl, showing the weight percent CaCl in the final tablet versus the concentration of CaCl in the ethanol. As can be seen, adding 10% and 20% CaCl in ethanol resulted in tablets that maintained their shape after two days, while lower CaCl concentrations failed to maintain their shape and spontaneously swelled within two days.

[0073] Referring to Figures 15B-15D, Figure 15B shows an initial 5 mm fibril tablet made with 10% CaCl2 ethanol solution (F-10Ca-Et), Figure 15C shows this tablet after 5 seconds in blood, and Figure 15D shows this tablet after 20 seconds in blood.

[0074] Referring to Figures 15E-15G, Figure 15E shows an initial 5 mm fibril tablet made with 20% CaCl2 ethanol solution (F-20Ca-Et), Figure 15F shows this tablet after 5 seconds in blood, and Figure 15G shows this tablet after 20 seconds in blood.

[0075] The presented data show that tablets made with a 10% CaCl2 solution composition (F-10Ca-Et) not only maintained their shape but also swelled very rapidly in blood. Tablets made with a 20% CaCl2 solution composition (F-20Ca-Et) maintained their shape but swelled more slowly in blood than F-10Ca-Et. Fibril compositions in 2% and 5% CaCl2-added ethanol solutions, F-2Ca-Et and F-5Ca-Et, were unable to maintain their shape and were not tested in blood.

[0076] Figure 16 shows the wt% concentration of CaCl in the final fibril ORC form for F-10Ca-Et and F-20Ca-Et for 5 mm compressed tablets, estimated to be 15.89% for F-10Ca-Et and 28.29% for F-20Ca-Et. Figure 17 shows the densities of F-10Ca-Et and F-20Ca-Et, estimated to be 0.50 and 0.59, respectively.

[0077] Further studies in animal models were conducted on F-10Ca-Et and F-20Ca-Et fibril ORC tablets.

[0078] The animals used in this study were female juvenile pigs weighing 55–70 kg. The bleeding model was established as a 6 mm biopsy punch (3 mm deep) on the liver or spleen. The female pigs were fasted for 24 h before the surgical procedure. The animals were anesthetized with 1150–1400 mg of ketamine, 115–140 mg of xylazine, and 7.5 mg of midazolam. Anesthesia was maintained with isoflurane, and the abdomen was opened to expose the spleen. Mean arterial blood pressure, body temperature, and heart rate were continuously monitored throughout the surgical procedure. The experiment was terminated when mean arterial blood pressure dropped below 60 mmHg. An 8 mm diameter x 3 mm deep biopsy punch was made on the spleen, and the specimen was excised with surgical scissors. The punch site was allowed to bleed for 30 seconds, and the bleeding intensity was visually assessed on a scale of 0–5 (see Figure 7). "No bleeding" was given a score of 0, and "heavy bleeding" was given a score of 5. The punch site was then wiped with clean gauze to remove excess blood, and a single tablet was inserted into the puncture wound. The bleeding rate was then assessed again. Manual compression was applied for 2 minutes, followed by a 30-second observation period. If hemostasis was not achieved during the 30-second observation period, another 30-second manual compression was applied, followed by another 30-second observation period. The time to hemostasis was determined if hemostasis was successfully achieved within 5 minutes and classified as a success (pass). If bleeding was still persistent at 5 minutes, the test was stopped as a failure and recorded as ">5 minutes" (more than 5 minutes).

[0079] For the heparinization model, adult female pigs weighing approximately 60 kg were treated as described above, laparotomized to expose the liver or spleen, and administered 27,000 IU of heparin prior to biopsy. Activated Clotting Time (ACT) testing was used to monitor heparinization. Therefore, heparin boosts were given to maintain stable ACT levels. Heparin is used as an injectable anticoagulant (through activation of antithrombin III). Therefore, this model represents a challenge bleeding model.

[0080] The liver was subjected to a biopsy punch with a diameter of 8 mm and a depth of 3 mm. The porcine spleen was subjected to a biopsy punch with a diameter of 6 mm and a depth of 3 mm. In both organs, specimens were excised with surgical scissors. The punch site was allowed to bleed for 30 seconds, and the bleeding intensity (level) was visually assessed on a scale of 0 to 5 as described above. The hemostatic effect was evaluated in the porcine liver and spleen. ORC tablets were manually applied to the wound site.

[0081] The test results are shown in Table 5.

[0082] [Table 6]

[0083] As shown, F-10Ca-Et tablets worked in all models, including non-heparinized liver punch (pig), heparinized liver punch (pig), and heparinized spleen punch (pig), whereas F-20Ca-Et worked in non-heparinized liver punch (pig), heparinized liver punch (pig), but failed in heparinized spleen punch (pig).

[0084] Example 6. Snow ORC Tablets with CaCl and Ethanol Similar to the process described above, compressed ORC forms were made from snow-ORC material by cutting 18 circular pieces from the snow. The cut snow circular pieces were then transferred to a 6 mm diameter circular die for addition of ethanol and CaCl2 and compression, followed by drying as described above. The 18 layers of ORC were compressed to the desired final length (thickness), such as 10 mm, 5 mm, or 3 mm, at the desired pressure using a texture analyzer. Referring to Figure 18, a comparison is shown in which 18 layers of snow (A) before compression are approximately the same thickness as 10 layers of fibrils (B), corresponding to a pre-compression thickness or length of 4-4.5 cm. After compression, both materials expanded to very similar expanded morphologies, yielding 5 mm long tablets and 3-3.5 cm long, as shown for Snow-C and Fibrils-D, while Snow-E and Fibrils-F exhibited at least a 5-fold expansion, more preferably 6-fold or greater expansion, and most preferably greater than 7-fold expansion.

[0085] As shown in Figure 18, the nonwoven ORC material is compressed from an initial stack of 4-4.5 cm length or height into tablets of 3, 5, and 10 mm length (thickness); i.e., the compression ratio, defined as the original length of the stack (free-standing, unweighted, uncompressed disks obtained from a 6 mm diameter punch) divided by the final tablet length, is approximately 13-15 for the 3 mm tablets, 8-9 for the 5 mm tablets, and 4-4.5 for the 10 mm tablets. Overall, the compression ratio is 4-15 for all tablets, or 8-15 for the 5 and 3 mm tablets. The maximum expansion of the 5 mm tablets is greater than 3-3.5 cm, or 6-7 times greater.

[0086] Figure 19 shows the weight % of CaCl2 in the final snow-compressed ORC tablets made with 10% CaCl2 in ethanol (S-10Ca-Et) at thicknesses of 3, 5, and 10 mm, corresponding to 9.55%, 16.28%, and 28.85%, respectively.

[0087] Figure 20 shows the wt% of CaCl in the final fibril-compressed ORC tablets (F-10Ca-Et) made with 10% CaCl in ethanol at thicknesses of 3, 5, and 10 mm, corresponding to similar concentrations of 10.45%, 15.89%, and 26.83%, respectively.

[0088] Example 7. Compressed fibril ORC tablets containing CaCl and ethanol further containing 4-arm PEG-SG-10K The inventors further discovered that it was advantageous to incorporate PEG-SG, a multi-arm polyethylene glycol functionalized with succinimidyl glutarate (or PEG-NHS). An acetone solution of 10 kDa 4-arm PEG-SG, designated PEG-SG-10K, was prepared at 0.2 g / ml.

[0089] In the first imbibition method for producing compressed tablets, 5 mm long F-10Ca-Et ORC tablets previously prepared as described above were treated by slowly adding 90 microliters of a 0.2 g / ml PEG-SG-10K acetone solution from a micropipette onto the ORC tablets until the solution was completely absorbed into the tablets. The tablets were then placed under a 4 Torr vacuum for 12 hours to allow complete evaporation of the solvent. The resulting F-10Ca-Et-SGa tablets produced by the imbibition method contained 0.018 g of PEG-SG-10K per tablet.

[0090] In the second spray method for making compressed tablets, 5 mm long F-10Ca-Et ORC tablets previously prepared as described above were treated by spraying a 0.2 g / mL PEG-SG-10K solution in acetone onto the ORC tablets from a spray bottle. The tablets were then placed under a 4 Torr vacuum for 12 hours to allow complete evaporation of the solvent. The resulting spray-prepared F-10Ca-Et-SGs tablets contained the same amount of PEG-SG-10K per tablet, 0.018 g.

[0091] Referring now to Figure 21A, testing of the F-10Ca-Et-SGa tablet made by the absorption method shows good swelling when exposed to 1 mL of citrated butanoic acid blood after 2 minutes of contact in a Petri dish. However, while good swelling is observed, after removal of the F-10Ca-Et-SGa tablet, there is some uncoagulated blood around the swollen tablet, as can be seen particularly in Figure 21B.

[0092] 22A, 22B, and 22C, testing of the spray-prepared F-10Ca-Et-SGs tablets shows good swelling after 2 minutes of contact when exposed to 1 mL of citrated butadiene blood. Good swelling is observed, but advantageously, there is little non-coagulated blood surrounding the swollen tablets.

[0093] In vitro and in vivo testing of compressed ORC tablets Further tests were performed in various models to evaluate the performance of embodiments of the present invention. Table 6 shows the various samples tested in the following examples.

[0094] [Table 7]

[0095] Example 8. In Vitro Burst Test: Heparinized Renal Biopsy Punch Model The study was performed in a biopsy punch model using heparinized bovine whole blood. Anticoagulation ratio: 1:99 (1000 IU / ml Na heparin to whole blood). Study organ: porcine kidney, purchased from Farm to Pharm LLC. Biopsy punch (ID): 4 mm. Mean arterial blood pressure at defect creation: 20 mmHg. Tamponade duration: 2 minutes. Observation period: 30 seconds. Definitions of "pass" and "fail": Pass: Hemostasis was maintained during the observation period. Fail: Hemostasis was not achieved during the observation period.

[0096] Experimental Procedure: The test article was applied onto the bleeding defect. Manual compression was applied for 2 minutes, followed by a 30-second observation period. If hemostasis was not achieved during the 30-second observation period, the test was stopped as a "fail." If hemostasis was achieved, it was considered a "pass," and blood pressure was then increased to test maximum burst value.

[0097] The results of the in vitro burst test are shown in Table 7.

[0098] [Table 8]

[0099] Analysis of the test results shows that control sample number 6 failed. Sample number 2 failed one test and passed one test. All other samples passed all tests.

[0100] Example 9. In vivo animal study: Heparinized porcine liver biopsy punch model The test was performed as follows: Animal species: Pig. Sex: Female. Age: Juvenile. Body weight: 55-70 kg. Organ studied: Liver. Biopsy punch (ID x thickness): 6 mm x 3 mm. Initial tamponade period: 2 minutes. Observation period: 30 seconds. Time to hemostasis: The test period from application of the test article to achieving hemostasis. Definitions of "pass" and "fail": Pass: Hemostasis achieved within 5 minutes. Fail: Hemostasis not achieved within 5 minutes.

[0101] Experimental Procedure: The test article was applied onto the bleeding defect. Manual compression was applied for 2 minutes, followed by a 30-second observation period. If hemostasis was not achieved during the 30-second observation period, another 30-second manual compression was applied, followed by another 30-second observation period. Time to hemostasis was determined if hemostasis was successfully achieved within 5 minutes and classified as a success (pass). If bleeding was still ongoing at 5 minutes, the test was stopped as a failure and recorded as ">5 minutes" (greater than 5 minutes).

[0102] Female Yorkshire pigs (animal number 56251, Animal Biotech Industries, Inc.) weighing 68 kg were used for each hemostatic test. The animals were ear-tagged and allowed to acclimate to the testing facility for at least 3 days before any procedures were performed. The animals were individually housed and fed standard pig chow once daily with water available ad libitum. Housing and care followed the standards of the Guide for the Care and Use of Laboratory Animals. The study was conducted by the CRF Skirball Center for Innovation (Orangeburg, NY, USA) in their AAALAC International-accredited facility. The animal protocol was reviewed and approved by the CRF Skirball Center for Innovation's Institutional Animal Care and Use Committee (IACUC). An in vivo porcine liver biopsy punch model was utilized to compare the hemostatic performance of test materials. The animals were anesthetized with an intramuscular injection of a combination of TZed (210 mg / 2.1 mL) and Glyco (0.28 mg / 1.4 mL). Subsequently, the animals were intubated and anesthesia was maintained by inhalation of 2% isoflurane mixed with 100% oxygen (1 L / min). Mechanical ventilation (10–20 mL / kg, 10–15 breaths / min) was used throughout the procedure. A catheter was inserted into the marginal ear vein of each pig for the delivery of fluids and medications as needed. Lactated Ringer's solution or saline was administered intravenously (IV) throughout the surgical procedure. Blood pressure was measured intra-arterially in the carotid artery using a catheter connected to a transducer. Heart and respiratory rate (HR, RR), electrocardiography (ECG), CO2, body temperature, and mean arterial blood pressure (MAP) were continuously monitored. Fluid infusion rates were adjusted as needed to maintain physiological blood pressure levels.

[0103] The exposed liver was kept moist using saline-soaked gauze. The animals were initially heparinized, and the activated clotting time was 344-417 seconds. A bleeding defect was created using a 6 mm biopsy punch 3 mm deep in the liver. The test article was first applied to the bleeding defect. Manual compression was applied for 2 minutes, followed by a 30-second observation period. If hemostasis was not achieved during the 30-second observation period, another 30 seconds of manual compression was applied, followed by another 30-second observation period. The time to hemostasis was determined if hemostasis was successfully achieved within 5 minutes and classified as a success (pass). If bleeding still persisted at 5 minutes, the test was stopped as a failure and recorded as ">5 minutes" (more than 5 minutes).

[0104] The results of the test are shown in Table 8.

[0105] [Table 9]

[0106] Analysis of the test results shows that control sample number 6 failed. Sample number 2 failed. Sample number 1 passed and achieved hemostasis only at the longer time of 4 minutes. Samples 3-5 containing PEG-SG all passed and achieved hemostasis in as short a time as 2 minutes.

[0107] A preferred embodiment is as follows:

[0108] Compacted nonwoven ORC, such as fibrils, treated with 10% CaCl2 in EtOH or F-10Ca-Et.

[0109] The most preferred embodiment is as follows: Compressed nonwoven ORC, such as fibrils, treated with 10% CaCl in EtOH and sprayed with 0.2 g / ml 4-arm-PEGSG10 K or F-10Ca-Et-SGs in acetone; Compressed nonwoven ORC, such as fibrils, treated with 10% CaCl2 in EtOH and reinforced with 0.2 g / ml 4-arm-PEGSG10 K or F-10Ca-Et-SGa in acetone, and Compressed nonwoven ORC such as snow treated with 10% CaCl2 in EtOH and sprayed with 0.2 g / ml 4-arm-PEGSG10 K or S-10Ca-Et-SGs in acetone.

[0110] Preferred embodiments are those made of multi-layer compressed OC form, more preferably ORC form, more preferably non-woven ORC material.

[0111] Preferred embodiments of compressed ORC tablets are stable after compression and do not expand spontaneously when not exposed to body fluids, blood, but expand and swell rapidly upon contact with blood and / or body fluids.

[0112] A preferred embodiment is made by combining a multi-layer ORC structure with CaCl2 in ethanol before compression.

[0113] A preferred embodiment is made by combining a multi-layer ORC structure with CaCl2 in ethanol before compression.

[0114] A preferred embodiment is made by combining a multilayer ORC structure with CaCl2 in ethanol before compression and further comprises PEG-SG.

[0115] A preferred embodiment comprises a compressed multi-layer ORC tablet containing CaCl2 and multi-arm PEG-SG.

[0116] In some embodiments, tablets may be applied manually or, in some embodiments, using a device such as a medical device (e.g., trocars of various sizes (e.g., 5, 10, 12, 15 mm, etc., in diameter) or other known applicators. Depending on the desired shape, form, and size for the intended use, different molds or other compression techniques can be used to achieve the desired body of the tablet or composition of the present disclosure.

[0117] The compressed ORC tablet may be of any shape or form, for example, having a substantially polygonal or rectangular (including substantially square) cross-section, a substantially circular cross-section, and / or a substantially oval cross-section along at least one axis. For example, the tablet may have a substantially box-like shape (having a substantially rectangular (optionally rounded) cross-section along three axes), a substantially cylindrical shape (having a substantially circular and / or substantially oval cross-section along one axis and a substantially rectangular (optionally rounded) cross-section along two axes), or a substantially spherical or oval shape (having a substantially circular and / or substantially oval cross-section along three axes). Other shapes, forms, and sizes of the compositions of the present disclosure may be selected from, but are not limited to, plugs, disks, rods, tubes, conical cylinders, spheres, hemispheres, cubes, rectangles, triangles, or disks.

[0118] In some embodiments, the volume of the tablet is less than 1 mm 3 In some embodiments, the tablet volume is at least 5 mm 3 In some embodiments, the volume of the matrix may be 10 mm 3 In some embodiments, the volume of the tablet can be greater than about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 mm 3 (including any value and range therebetween). In some embodiments, the volume of the tablet is 100 mm 3 In some embodiments, the volume of the tablet may be about 1 to 100 mm 3, 1 to 10 mm 3 (For example, about 5 mm 3 ) As used herein, by "tablet volume" is meant to refer to the unswollen state (i.e., before exposure to body fluids).

[0119] The term "oxidized cellulose" (or "OC") refers to a cellulose derivative in which at least a portion of the primary alcohol groups, e.g., the 6-carbon of the anhydroglucose unit, have been oxidized to a carboxylic acid, and optionally functionalized. OC can include materials, products, articles, or compositions (e.g., bandages, fibrin glues, synthetic adhesives, pads, matrices, powders, tabs, pills, sutures, fibers, stents, implants, scaffolds, solutions, gels, waxes, gelatins, etc.) that comprise or consist essentially of OC.

[0120] OC can be produced by applying an oxidizing agent to cellulose. The oxidizing agent can be selected from, but is not limited to, chlorine, hydrogen peroxide, peracetic acid, chlorine dioxide, nitrogen dioxide, persulfates, permanganates, dichromate-sulfuric acid, hypochlorous acid, hypohalites, periodates, or any combination thereof, and / or various metal catalysts. Depending on the nature of the oxidizing agent and reaction conditions, the oxidized cellulose may contain carboxylic acid, aldehyde, and / or ketone groups in place of, or in addition to, the original hydroxyl groups of the starting cellulose.

[0121] In exemplary embodiments, the OC is oxidized to contain carboxyl moieties in an amount effective to provide biodegradability. For example, U.S. Patent No. 3,364,200 discloses the preparation of carboxylic acid-oxidized cellulose using an oxidizing agent such as dinitrogen tetroxide in a Freon medium. U.S. Patent No. 5,180,398 discloses the preparation of carboxylic acid-oxidized cellulose using an oxidizing agent such as nitrogen dioxide in a perfluorocarbon solvent. After oxidation by either method, the fabric may be thoroughly washed with a solvent such as carbon tetrachloride, followed by a 50 percent aqueous solution of isopropyl alcohol (IPA), and finally 99% IPA. Prior to oxidation, the fabric may be constructed in any desired woven or nonwoven structure.

[0122] As used herein with reference to OC, the terms "oxidation level," "degree of oxidation," "carboxyl content," and "carboxylation level" are interchangeable and may be determined in accordance with United States Pharmacopeia (USP) 23-NF18.

[0123] Thus, in some embodiments, the carboxyl content of the OC is 12-24% by weight. In some embodiments, the carboxyl content of the OC is 12-23% by weight. In some embodiments, the carboxyl content of the OC is 12-22% by weight. In some embodiments, the carboxyl content of the OC is 12-21% by weight.

[0124] In some embodiments, the OC has a carboxyl content of 16-24% by weight, and the composition may function as a hemostat. In some embodiments, the OC has a carboxyl content of 17-23% by weight. In some embodiments, the OC has a carboxyl content of 18-22% by weight. In some embodiments, the OC has a carboxyl content of 18-21% by weight.

[0125] In some embodiments, the carboxyl content of the OC is 12-18% by weight, 12-17% by weight, 12-16% by weight.

[0126] In some embodiments, the carboxyl content of the OC is 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, or 24% (by weight), including any value and range therebetween.

[0127] In certain embodiments of the present invention, the OC (e.g., ORC) can be further combined with hemostatic agents, including drugs and pharmaceuticals, or other biological or therapeutic compounds, moieties, or species. In some embodiments, to improve hemostatic performance, scaffolds based on the above materials can be combined with biologically derived clotting factors, such as thrombin and fibrinogen. In yet other embodiments, the ORC-based composition can be combined with additives such as carboxymethyl cellulose (CMC), calcium salts, anti-infective agents, hemostatic promoters, gelatin, collagen, saline, or any combination thereof.

[0128] In further embodiments of the present invention, the ORC-based compositions of the present disclosure can be combined with various additives to further improve hemostatic, wound healing, and handling properties. Use of additives known to those skilled in the art includes, for example, hemostatic additives (such as gelatin, collagen, cellulose, chitosan, polysaccharides, starch, etc.) and biologic hemostatic agents (exemplified by thrombin, fibrinogen, and fibrin). Additional biologic hemostatic agents include, but are not limited to, procoagulant enzymes, proteins, and peptides. Such agents may each be natural, recombinant, or synthetic, and may further be selected from fibronectin, heparinase, Factor X / Xa, Factor VII / VIIa, Factor IX / IXa, Factor XI / XIa, Factor XII / XIIa, tissue factor, batroxobin, ancrod, ecarin, von Willebrand factor, albumin, platelet surface glycoproteins, vasopressin and vasopressin analogs, epinephrine, selectins, protocoagulant toxins, plasminogen activator inhibitors, platelet activators, synthetic peptides with hemostatic activity, derivatives of the above, and any combination thereof, anti-infective agents (e.g., chlorhexidine gluconate (CHG), triclosan, silver, and similar antibacterial / antimicrobial agents known in the art), additives that increase the adhesiveness of the hemostat, and other additives known in the art.

[0129] "Nonwoven" refers to a fabric-like material made from long fibers bonded together by chemical, mechanical, thermal, or solvent treatment. The term is used in the textile manufacturing industry to describe fabrics, such as felt, that are not woven or knitted. Thus, the phrase "nonwoven" refers to a sheet, web, or mat of directionally or randomly oriented fibers in which the fibers are not intermeshed but are bonded through various means, including, for example, friction, cohesion, and / or adhesion. The term "nonwoven" also includes, but is not limited to, bonded, formed, or modified fabrics made by processes other than spinning, weaving, or knitting.

[0130] In some embodiments, the tablet further comprises a pharmaceutically acceptable excipient or additive, which may include any pharmaceutically suitable excipient, such as, but not limited to, calcium salts, human albumin, mannitol, sodium acetate, sodium chloride, sodium citrate dihydrate, gluconate buffer, sucrose, glycine, sodium acetate, histidine, and polyethylene glycol.

[0131] In one aspect of the present invention, a method of treating a wound is provided, comprising applying (e.g., contacting) a biodegradable hemostatic tablet disclosed in any embodiment thereof onto and / or within a wound of a subject in need of such treatment.

[0132] "Treating a wound" is further meant to encompass reducing blood loss at a bleeding site in tissue, for example, in a patient undergoing surgery. Thus, in some embodiments, the method is for reducing blood loss at a bleeding site in tissue, for example, in a patient undergoing surgery, and comprises contacting the bleeding site with a composition of the present disclosure in that embodiment.

[0133] In another aspect of the present disclosure, tablets are provided, produced by a method of compressing an OC-based material by applying pressure to its surface as described herein. In some embodiments, compression is applied by applying pressure, for example, using a hydraulic press. In some embodiments, the applied pressure is about 0.2 to about 7 ton / cm. 2 and includes any value and range therebetween.

[0134] In some embodiments of the method, the OC material comprises ORC. In some embodiments of the method, the ORC is in a nonwoven form. In some embodiments, the method further comprises mixing the OC material with one or more additives selected from, but not limited to, calcium salts, anti-infective agents, and hemostasis-promoting agents.

[0135] These results indicate that compressed tablets made from nonwoven ORC materials exhibit greater efficacy than prior art compressed forms.

[0136] While the present invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.

[0137] [Embodiment] (1) A compression hemostatic configuration having a longitudinal axis and a length measured along said axis, a) a fibrous nonwoven oxidized cellulose (OC) multilayer material compressed into a form-stable tablet; b) a calcium salt, A compressed hemostatic form in which the tablet rapidly expands along at least the longitudinal axis upon contact with liquid plasma. (2) The compressed form of embodiment 1, further comprising multi-arm polyethylene succinimidyl glutarate (PEG-SG). (3) The compressed form of embodiment 1, wherein the tablet has a dimensionally stable length measured along its longitudinal axis for at least 48 hours after compression. (4) The compressed form of embodiment 1, wherein the tablet has a compression ratio of at least 4 times. (5) The compressed form of embodiment 1, wherein the tablet has a compression ratio of at least 8 times.

[0138] (6) The compressed form of embodiment 1, wherein the tablet has a compression ratio of at least 13 times. (7) The compressed form of embodiment 1, wherein the tablet has a tablet length of 3 to 10 mm. (8) The compressed form of embodiment 7, wherein the tablet, upon contact with blood or plasma, expands to 1.5 to 5 times its length in 5 seconds, to 2 to 6 times its length in 20 seconds, and to 3 to 6 times its length in 5 minutes. (9) The compressed form of embodiment 2, wherein the tablet is effective in achieving hemostasis as shown in a punch liver or spleen porcine model using heparinized blood. (10) The compressed form of embodiment 1, wherein the OC material comprises oxidized regenerated cellulose (ORC).

[0139] 11. The compressed form of claim 10, wherein the ORC material comprises a compressed form of at least 10 layers of nonwoven fibrous ORC material. (12) The compressed form of embodiment 1, further comprising a coagulant, a clotting factor, an anti-infective agent, or a combination thereof. (13) The compressed form of embodiment 1, wherein the form is made by compressing a stack of nonwoven OC material in the presence of a calcium salt solution in ethanol, followed by drying under vacuum to evaporate the ethanol. (14) The compressed form of embodiment 2, wherein the form is made by compressing a stack of nonwoven OC material in the presence of a calcium salt solution in ethanol, followed by drying under vacuum, evaporating the ethanol, and then contacting with a solution of the multi-arm PEG-SG in a volatile solvent and vacuum drying. (15) a) cutting a plurality of pieces of nonwoven OC material; b) placing the plurality of pieces of nonwoven OC material into a stack within a compression die; c) adding a solution of calcium salt in ethanol to the compression die; d) compressing the stack to a compression ratio of at least 4 to form a compressed stack; e) drying the compressed stack to evaporate substantially all of the ethanol and form the stable compressed tablet form.

[0140] (16) (i) step (e) is performed with the stack inside the compression die; (ii) after step (e), a further step (f) is carried out, which step (f) comprises: f) removing the stable tablet from the compression die. (17) Step (g) or (h), i.e. g) absorbing a solution of multi-arm PEG-SG in a volatile solvent onto the tablet and drying the tablet under vacuum; or h) spraying said tablet with said solution of said multi-arm PEG-SG in said volatile solvent and vacuum drying said tablet. (18) A method of treating a wound, comprising applying the compressed form of embodiment 1 onto and / or into a wound of a subject in need of achieving hemostasis.

Claims

1. A compression hemostatic configuration having a longitudinal axis and a length measured along said axis, a) a fibrous nonwoven oxidized cellulose (OC) multilayer material compressed into a form-stable tablet; b) a calcium salt, A compressed hemostatic form in which the tablet rapidly expands along at least the longitudinal axis upon contact with liquid plasma.

2. 10. The compressed form of claim 1, further comprising multi-arm polyethylene succinimidyl glutarate (PEG-SG).

3. 10. The compressed form of claim 1, wherein the tablet has a dimensionally stable length measured along its longitudinal axis for at least 48 hours after compression.

4. 10. The compressed form of claim 1, wherein the tablet has a compression ratio of at least 4 times.

5. 10. The compressed form of claim 1, wherein the tablet has a compression ratio of at least 8 times.

6. 10. The compressed form of claim 1, wherein the tablet has a compression ratio of at least 13 times.

7. 2. The compressed form of claim 1, wherein the tablet has a tablet length of 3 to 10 mm.

8. 8. The compressed form of claim 7, wherein the tablet, upon contact with blood or plasma, expands to 1.5 to 5 times its length in 5 seconds, to 2 to 6 times its length in 20 seconds, and to 3 to 6 times its length in 5 minutes.

9. 3. The compressed form of claim 2, wherein the tablet is effective in achieving hemostasis as shown in a punch liver or spleen porcine model using heparinized blood.

10. The compressed form of claim 1 , wherein the OC material comprises oxidized regenerated cellulose (ORC).

11. The compressed form of claim 10 , wherein the ORC material comprises a compressed form of at least 10 layers of non-woven fibrous ORC material.

12. 10. The compressed form of claim 1, further comprising a clotting agent, a clotting factor, an anti-infective agent, or a combination thereof.

13. 10. The compressed form of claim 1, wherein the form is made by compressing a stack of nonwoven OC material in the presence of a calcium salt solution in ethanol, followed by drying under vacuum to evaporate the ethanol.

14. 3. The compressed form of claim 2, wherein the form is made by compressing a stack of nonwoven OC material in the presence of a calcium salt solution in ethanol, followed by drying under vacuum to evaporate the ethanol, followed by contact with a solution of the multi-arm PEG-SG in a volatile solvent and vacuum drying.

15. a) cutting a plurality of pieces of nonwoven OC material; b) placing the plurality of pieces of nonwoven OC material as a stack in a compression die; c) adding a solution of calcium salt in ethanol to the compression die; d) compressing the stack to a compression ratio of at least 4 to form a compressed stack; e) drying the compressed stack to evaporate substantially all of the ethanol and form the stable compressed tablet form.

16. (i) step (e) is performed with the stack inside the compression die; (ii) after step (e), a further step (f) is carried out, which step (f) comprises:

16. A method of making the compressed form of claim 15, comprising: f) removing the stable tablet from the compression die.

17. Step (g) or (h), i.e. g) absorbing a solution of multi-arm PEG-SG in a volatile solvent into the tablet and drying the tablet under vacuum; or 17. The method of making the compressed form of claim 16, further comprising the steps of: h) spraying the tablet with the solution of the multi-arm PEG-SG in the volatile solvent and vacuum drying the tablet.

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