U.S. patent application number 13/648902 was filed with the patent office on 2013-04-18 for hemostatic compositions.
This patent application is currently assigned to Baxter Healthcare S.A.. The applicant listed for this patent is Baxter Healthcare S.A., Baxter International Inc.. Invention is credited to Katarzyna Gorna, Hans Christian Hedrich, Joris Hoefinghoff.
Application Number | 20130096063 13/648902 |
Document ID | / |
Family ID | 47018202 |
Filed Date | 2013-04-18 |
United States Patent
Application |
20130096063 |
Kind Code |
A1 |
Hedrich; Hans Christian ; et
al. |
April 18, 2013 |
HEMOSTATIC COMPOSITIONS
Abstract
The invention discloses a hemostatic composition comprising: a)
a biocompatible polymer in particulate form suitable for use in
hemostasis, and b) one hydrophilic polymeric component comprising
reactive groups.
Inventors: |
Hedrich; Hans Christian;
(Vienna, AT) ; Hoefinghoff; Joris; (Vienna,
AT) ; Gorna; Katarzyna; (Vienna, AT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Baxter International Inc.;
Baxter Healthcare S.A.; |
Deerfield
Glattpark (Opfikon) |
IL |
US
CH |
|
|
Assignee: |
Baxter Healthcare S.A.
Glattpark (Opfikon)
IL
Baxter International Inc.
Deerfield
|
Family ID: |
47018202 |
Appl. No.: |
13/648902 |
Filed: |
October 10, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61545909 |
Oct 11, 2011 |
|
|
|
Current U.S.
Class: |
514/13.7 |
Current CPC
Class: |
A61L 24/043 20130101;
A61L 26/0052 20130101; A61L 24/0031 20130101; A61K 38/17 20130101;
A61K 38/42 20130101; A61K 38/38 20130101; A61L 2400/04 20130101;
A61P 17/02 20180101; A61L 26/008 20130101; A61K 31/765 20130101;
A61L 26/0052 20130101; C08L 71/02 20130101; A61L 24/043 20130101;
C08L 71/02 20130101; A61L 24/043 20130101; C08L 89/00 20130101;
A61L 26/0052 20130101; C08L 89/00 20130101 |
Class at
Publication: |
514/13.7 |
International
Class: |
A61K 38/17 20060101
A61K038/17; A61K 31/765 20060101 A61K031/765 |
Claims
1. A hemostatic composition comprising: a) a biocompatible polymer
in particulate form suitable for use in hemostasis; and b) one
hydrophilic polymeric component comprising reactive groups.
2. The hemostatic composition according to claim 1, wherein the
biocompatible polymer and the hydrophilic polymeric component are
present in dry form.
3. The hemostatic composition according to claim 1, wherein said
biocompatible polymer suitable for use in hemostasis contains a
member selected from the group consisting of a protein, a
polysaccharide, a biologic polymer, a non-biologic polymer; and
derivatives and combinations thereof.
4. The hemostatic composition according to claim 1, wherein said
biocompatible polymer suitable for use in hemostasis contains a
protein selected from the group consisting of gelatin, collagen,
albumin, hemoglobin, fibrinogen, fibrin, casein, fibronectin,
elastin, keratin, and laminin; and derivatives and combinations
thereof.
5. The hemostatic composition according to claim 1, wherein said
biocompatible polymer suitable for use in hemostasis contains a
crosslinked protein, a crosslinked polysaccharide, a crosslinked
biologic polymer, a crosslinked non-biologic polymer; or mixtures
thereof.
6. The hemostatic composition according to claim 1, wherein the
hydrophilic polymer component is a polyalkylene oxide polymer.
7. The hemostatic composition according to claim 1, wherein said
hydrophilic polymeric component with reactive groups is a
polyethylene glycol (PEG).
8. The hemostatic composition according to claim 1, wherein the
biocompatible polymer is crosslinked gelatin and the hydrophilic
polymeric component is pentaerythritolpoly(ethyleneglycol)ether
tetrasuccinimidyl glutarate.
9. The hemostatic composition according to claim 1, provided in dry
form in an administration container.
10. A method of treating a patient, comprising administering to the
patient a hemostatic composition according to claim 1 for the
treatment of an injury selected from the group consisting of a
wound, a hemorrhage, a damaged tissue, a bleeding tissue, and a
bone defect.
11. A method of treating an injury selected from the group
consisting of a wound, a hemorrhage, a damaged tissue, and a
bleeding tissue comprising administering the hemostatic composition
of claim 1 to the injury.
12. A method for producing a hemostatic composition according to
claim 1 comprising the step of mixing a biocompatible polymer
suitable for use in hemostasis and one hydrophilic polymeric
component comprising reactive groups in dry form.
13. A kit comprising a hemostatic composition in dry form according
to claim 1 and a diluent for reconstitution of the hemostatic
composition.
14. A method for providing a ready to use form of a hemostatic
composition according to claim 1, wherein the hemostatic
composition is provided in a first syringe and a diluent for
reconstitution is provided in a second syringe, the first and the
second syringe are connected to each other, and the diluent is
brought into the first syringe to produce a flowable form of the
hemostatic composition.
15. The hemostatic composition according to claim 2, wherein the
biocompatible polymer and the hydrophilic polymeric component are
present in mixed dry form.
16. The hemostatic composition according to claim 6, wherein the
polyalkylene oxide polymer is a PEG comprising polymer.
17. The hemostatic composition according to claim 6, wherein the
polyalkylene oxide polymer is a multi-electrophilic polyalkylene
oxide polymer.
18. The hemostatic composition according to claim 6, wherein the
polyalkylene oxide polymer is a multi-electrophilic PEG.
19. The hemostatic composition according to claim 6, wherein the
polyalkylene oxide polymer is
pentaerythritolpoly(ethyleneglycol)ether tetrasuccinimidyl
glutarate.
20. The hemostatic composition according to claim 7, wherein the
hydrophilic polymeric component with reactive groups is a
polyethylene glycol (PEG) comprising two or more reactive groups
selected from succinimidylesters (--CON(COCH.sub.2).sub.2),
aldehydes (--CHO) and isocyanates (--N.dbd.C.dbd.O).
Description
[0001] This application claims the benefit of U.S. Ser. No.
61/545,909 filed Oct. 11, 2011, which is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to hemostatic compositions and
processes for making such compositions.
BACKGROUND OF THE INVENTION
[0003] Hemostatic compositions in dry storage-stable form that
comprise biocompatible, biodegradable, dry stable granular material
are known e.g. from WO98/008550A or WO 2003/007845A. These products
have been successfully applied on the art for hemostasis.
Floseal.RTM. is an example for a powerful and versatile hemostatic
agent consisting of a granular gelatin matrix swollen in a
thrombin-containing solution to form a flowable paste.
[0004] Since such products have to be applied to humans, it is
necessary to provide highest safety standards for quality,
storage-stability and sterility of the final products and the
components thereof. On the other hand, manufacturing and handling
should be made as convenient and efficient as possible.
[0005] On the other hand, it has been found that previous
hemostatic compositions for wound healing failed to induce
hemostasis at conditions with impaired hemostasis (e.g. after
heparinization). It is therefore desired to provide materials and
compositions with improved hemostasis. Moreover, a strong adherence
of the compositions applied to the tissue is needed when the
composition is applied to a wound. It is also desired to provide
material with suitable swelling behavior after application to a
wound.
[0006] It is an object of the present invention to overcome such
problems and provide suitable hemostatic compositions with improved
adhering properties and methods for making such hemostatic
composition. The compositions should also be provided in a
convenient and usable manner. The products should preferably be
provided in product formats enabling a convenient provision of
"ready-to-use" hemostatic compositions, which can be directly
applied to an injury without any time consuming reconstitution
steps.
SUMMARY OF THE INVENTION
[0007] Therefore, the present invention provides a hemostatic
composition comprising: [0008] a) a biocompatible polymer in
particulate form suitable for use in hemostasis, and [0009] b) one
hydrophilic polymeric component comprising reactive groups.
[0010] The combination of a biocompatible polymer in particulate
form with one hydrophilic polymeric component provides a
composition with improved hemostatic properties and with improved
tissue adherence. This is specifically suitable for wound treatment
wherein induction of hemostasis failed, e.g. at conditions with
impaired hemostasis (e.g. after heparinization). The compositions
according to the present invention improve hemostasis. Furthermore,
the compositions according to the present invention show a strong
adherence to the tissue when applied to a wound.
[0011] Upon contact with bleeding tissue, a crosslinking reaction
of the hydrophilic polymeric component with the blood proteins
leads to formation of a gel with sealing and hemostatic properties.
Crosslinking also occurs to the tissue surface proteins and,
depending on the nature of the biocompatible polymer material, may
also occur to the biocompatible polymer material. The latter
reaction contributes to an improved adhesion of the composition
material to the wounded tissue surface.
[0012] A further aspect relates to a method of treating an injury
comprising administering a hemostatic composition to the site of
injury.
[0013] Also provided is a kit for the treatment of an injury,
comprising a hemostatic composition as herein disclosed and
instructions for use.
[0014] The present invention also refers to a method for producing
the hemostatic composition according to the invention in a
convenient manner allowing the composition to be easily at hand for
medical use. The invention further relates to a method for
delivering a hemostatic composition to a target site in a patient's
body, said method comprising delivering a hemostatic composition
produced by the process of the present invention to the target
site. According to another aspect, the present invention relates to
a finished final container obtained by the process according of the
present invention containing the present hemostatic composition.
The invention also relates to a method for providing a ready-to-use
hemostatic composition comprising contacting a hemostatic
composition produced by the process of the present invention with a
pharmaceutically acceptable diluent as well as to a kit comprising
the finished final container and other means for applying the
composition (e.g. a diluent container). The compositions according
to the present invention are particularly useful for providing
hemostasis at bleeding sites, including surgical bleeding sites,
traumatic bleeding sites and the like. An exemplary use of the
compositions may be in sealing the tissue tract above a blood
vessel penetration created for vascular catheterization.
DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION
[0015] The present invention provides an improvement in hemostatic
compositions. The hemostatic compositions according to the
invention contain biocompatible polymers in particulate form, e.g.
granules of a biocompatible polymer (e.g. gelatin, fibrin,
chitosan, fibronectin, collagen, especially gelatin) suitable for
use in hemostasis (the "hemostatic biocompatible polymer component"
or the "hemostatic polymer. Admixed to this biocompatible polymer
for hemostasis is one hydrophilic polymeric component comprising
reactive groups. According to the present invention, the reactive
groups of the polymeric component have retained their reactivity
until the composition is brought to the place of clinical action,
e.g. on to the wound.
[0016] The biocompatible polymers in particulate form suitable for
use in hemostasis may include dimensionally isotropic or
non-isotropic forms. For example, the biocompatible polymers
according to the present invention may be granules or fibers; and
may be present in discontinuous structures, for example in powder
forms.
[0017] According to a preferred embodiment, the biocompatible
polymer is liquid absorbing. For example, upon contact with
liquids, e.g. aqueous solutions or suspensions (especially a buffer
or blood) the polymer takes up the liquid and will display a degree
of swelling, depending on the extent of hydration. The material
preferably absorbs from about 200% to about 2000%, especially from
about 400% to about 1300% wafer or aqueous buffer by weight,
corresponding to a nominal increase in diameter or width of an
individual particle of subunit in the range from e.g. approximately
50% to approximately 500%, usually from approximately 50% to
approximately 250%. For example, if the (dry) granular particles
have a preferred size range of 0.01 mm to 1.5 mm, especially of
0.05 mm to 1 mm, the fully hydrated composition (e.g. after
administration on a wound or after contact with an aqueous buffer
solution) may have a size range of 0.05 mm to 3 mm, especially of
0.25 mm to 1.5 mm.
[0018] The equilibrium swell of preferred biocompatible polymers of
the present invention may generally range e.g. from 400% to 1300%,
preferably being from 500% to 1100%, depending on its intended use.
Such equilibrium swell may be controlled e.g. (for a crosslinked
polymer) by varying the degree of crosslinking, which in turn is
achieved by varying the crosslinking conditions, such as the type
of crosslinking method, duration of exposure of a crosslinking
agent, concentration of a crosslinking agent, crosslinking
temperature, and the like. Materials having differing equilibrium
swell values perform differently in different applications. For
example, the ability to inhibit bleeding in a liver divot model was
most readily achieved with crosslinked gelatin materials having a
swell in the range from 700% to 950%. For a femoral artery plug,
lower equilibrium swell values in the range from 500% to 600% were
more successful. Thus, the ability to control crosslinking and
equilibrium swell allows the compositions of the present invention
to be optimized for a variety of uses. In addition to equilibrium
swell, it is also important to control the hydration of the
material immediately prior to delivery to a target site. Hydration
and equilibrium swell are, of course, intimately connected. A
material with 0% hydration will be non-swollen. A material with
100% hydration will be at its equilibrium water content. Hydrations
between 0% and 100% will correspond to swelling between the minimum
and maximum amounts.
[0019] According to a preferred embodiment of the present
invention, the biocompatible polymer and the hydrophilic polymeric
component are present in dry form, preferably in mixed dry
form.
[0020] The biocompatible polymer in particulate form suitable for
use in hemostasis of the present invention may be formed from
biologic and non-biologic polymers. Suitable biologic polymers may
contain a protein, a polysaccharide, a biologic polymer, a
non-biologic polymer; and derivatives and combinations thereof.
Suitable proteins include gelatin, collagen, albumin, hemoglobin,
fibrinogen, fibrin, casein, fibronectin, elastin, keratin, and
laminin; and derivatives and combinations thereof. Particularly
preferred is the use of gelatin or soluble non-fibrillar collagen,
more preferably gelatin, and exemplary gelatin formulations are set
forth below. Other suitable biologic polymers include
polysaccharides, such as glycosaminoglycans, starch, cellulose,
dextran, hemicellulose, xylan, agarose, alginate and chitosan; and
derivatives and combinations thereof. Suitable non-biologic
polymers will be selected to be degradable by either of two
mechanisms, i.e. (1) break down of the polymeric backbone or (2)
degradation of side chains which result in aqueous solubility.
Exemplary non-biologic biocompatible polymers suitable for use in
hemostasis include synthetics, such as polyacrylates,
polymethacrylates, polyacrylamides, polymethacrylamides,
polyethyleneimines, polyvinyl resins, polylactide-glycolides,
polycaprolactones, and polyoxyethlenes; and derivatives and
combinations thereof. Also combinations of different kinds of
polymers are possible (e.g. proteins with polysaccharides, proteins
with non-biologic hydrogel-forming polymers, etc.). Preferred
hemostatic polymers comprise amino-groups, specifically if the
hydrophilic polymeric component has reactive groups which react
with amino-groups upon administration (e.g. in the wound
environment).
[0021] "A derivative thereof" includes any chemically modified
polymer, such as e.g. a crosslinked polymer.
[0022] Preferred hemostatic polymers comprise nucleophilic groups,
such as e.g. amino-groups, specifically if the hydrophilic
polymeric component has reactive groups which react with
amino-groups upon administration (e.g. in the wound
environment).
[0023] According to a preferred embodiment of the present
invention, the biocompatible polymer is selected from the group
consisting of gelatin, collagen, albumin, fibrinogen, fibrin and
derivatives thereof (as defined above); especially preferred the
polymer is gelatin or collagen; especially preferred is crosslinked
gelatin.
[0024] According to a preferred embodiment of the present
invention, the biocompatible polymer suitable for use in hemostasis
contains a crosslinked protein, a crosslinked polysaccharide, a
crosslinked biologic polymer, a crosslinked non-biologic polymer;
or mixtures thereof.
[0025] A non-crosslinked polymer may be crosslinked in any manner
suitable to reconstitute, e.g. to form a suitable hydrogel base of
the hemostatic polymer. For example, polymeric molecules may be
crosslinked using bi- or poly-functional crosslinking agents which
covalently attach to two or more polymer molecules chains.
Exemplary bifunctional crosslinking agents include aldehydes,
epoxides, succinimides, carbodiimides, maleimides, azides,
carbonates, isocyanates, divinyl sulfone, alcohols, amines,
imidates, anhydrides, halides, silanes, diazoacetate, aziridines,
and the like. Alternatively, crosslinking may be achieved by using
oxidizers and other agents, such as periodates, which activate
side-chains or moieties on the polymer so that they may react with
other side-chains or moieties to form the crosslinking bonds. An
additional method of crosslinking comprises exposing the polymers
to radiation, such as gamma radiation, to activate the polymer
chains to permit crosslinking reactions. Dehydrothermal
crosslinking methods may also be suitable. Preferred methods for
crosslinking gelatin molecules are described below.
[0026] The biocompatible hemostatic polymer--once applied to a
wound--forms an efficient matrix which can form a barrier for blood
flow. Specifically the swelling properties of the hemostatic
polymer can make it an effective mechanical barrier against
bleeding and rebleeding processes.
[0027] In a preferred embodiment, the hemostatic compositions
according to the present invention are provided or used as granular
preparations. According to a preferred embodiment, the
biocompatible polymer granulates suitable for use in hemostasis
contain a crosslinked protein, a crosslinked polysaccharide, or a
crosslinked non-biologic polymer; or mixtures thereof.
[0028] As mentioned above, the biocompatible polymer suitable for
use in hemostasis is preferably a granular material. This granular
material can rapidly swell when exposed to a fluid (i.e. the
diluent) and in this swollen form is capable of contributing to a
flowable paste that can be applied to a bleeding site. The
biocompatible polymer, e.g. gelatin, may be provided as a film
which can then be milled to form a granular material. Most of the
particles contained in this granular material (e.g. more than 90%
w/w) have preferably particle sizes of 10 to 1,000 .mu.m,
especially 50 to 700 .mu.m.
[0029] According to a preferred embodiment, the biocompatible
polymer in particulate form suitable for use in hemostasis is a
crosslinked gelatin. Dry crosslinked gelatin powder can be prepared
to re-hydrate rapidly if contacted with a pharmaceutically
acceptable diluent. The gelatin granules, especially in the form of
a gelatin powder, preferably comprise relatively large particles,
also referred to as fragments or sub-units, as described in
WO98/08550A and WO2003/007845A. A preferred (median) particle size
will be the range from 10 to 1,000 .mu.m, preferably from 50 to 700
.mu.m, but particle sizes outside of this preferred range may find
use in many circumstances. The dry compositions will also display a
significant "equilibrium swell" when exposed to an aqueous
re-hydrating medium (=diluents, also referred to as reconstitution
medium or re-hydration medium). Preferably, the swell will be in
the range from 400% to 1000%. "Equilibrium swell" may be determined
by subtracting the dry weight of the gelatin hydrogel powder from
its weight when fully hydrated and thus fully swelled. The
difference is then divided by the dry weight and multiplied by 100
to give the measure of swelling. The dry weight should be measured
after exposure of the material to an elevated temperature for a
time sufficient to remove substantially all residual moisture,
e.g., two hours at 120.degree. C. The equilibrium hydration of the
material can be achieved by immersing the dry material in a
pharmaceutically acceptable diluent, such as aqueous saline, for a
time period sufficient for the water content to become constant,
typically for from 18 to 24 hours at room temperature.
[0030] Exemplary methods for producing crosslinked gelatins are as
follows. Gelatin is obtained and suspended in an aqueous solution
to form a non-crosslinked hydrogel, typically having a solids
content from 1% to 70% by weight, usually from 3% to 10% by weight.
The gelatin is crosslinked, typically by exposure to either
glutaraldehyde (e.g., 0.01% to 0.05% w/w, overnight at 0.degree. C.
to 15.degree. C. in aqueous buffer), sodium periodate (e.g., 0.05
M, held at 0.degree. C. to 15.degree. C. for 48 hours) or
1-ethyl-3-(3-dimethylaminopropyl) carbodiimide ("EDC") (e.g., 0.5%
to 1.5% w/w overnight at room temperature), or by exposure to about
0.3 to 3 megarads of gamma or electron beam radiation.
Alternatively, gelatin particles can be suspended in an alcohol,
preferably methyl alcohol or ethyl alcohol, at a solids content of
1% to 70% by weight, usually 3% to 10% by weight, and crosslinked
by exposure to a crosslinking agent, typically glutaraldehyde
(e.g., 0.01% to 0.1% w/w, overnight at room temperature). In the
case of aldehydes, the pH should be held from about 6 to 11,
preferably from 7 to 10. When crosslinking with glutaraldehyde, the
crosslinks are formed via Schiff bases which may be stabilized by
subsequent reduction, e.g., by treatment with sodium borohydride.
After crosslinking, the resulting granules may be washed in water
and optionally rinsed in an alcohol, and dried. The resulting dry
powders may then be provided in the final container as described
herein.
[0031] Preferably, the biocompatible polymer is provided in a dry
granular form for producing the hemostatic compositions according
to the present invention. A "dry granular preparation of a
biocompatible polymer" according to the present invention is known
e.g. from WO 98/08550 A. Preferably, the polymer is a
biocompatible, biodegradable dry stable granular material.
[0032] The dry polymer according to the present invention Is
usually provided with particle sizes of 10 to 1,000 .mu.m. Usually,
the polymer particles have a mean particle diameter ("mean particle
diameter" is the median size as measured by laser diffractometry;
"median size" (or mass median particle diameter) is the particle
diameter that divides the frequency distribution in half; fifty
percent of the particles of a given preparation have a larger
diameter, and fifty percent of the particles have a smaller
diameter) from 10 to 1000 .mu.m, especially 50 to 700 .mu.m (median
size). Applying larger particles is mainly dependent on the medical
necessities; particles with smaller mean particle diameters are
often more difficult to handle in the production process. The dry
polymer is therefore provided in granular form. Although the terms
powder and granular (or granulates) are sometimes used to
distinguish separate classes of material, powders are defined
herein as a special sub-class of granular materials. In particular,
powders refer to those granular materials that have the finer grain
sizes, and that therefore have a greater tendency to form clumps
when flowing. Granules include coarser granular materials that do
not tend to form clumps except when wet. For the present
application the particles used are those which can be coated by
suitable coating techniques Particle size of the polymer granules
according to the present invention can therefore easily be adapted
and optimized to a certain coating technique by the necessities of
this technique.
[0033] The hydrophilic polymeric component (also referred to as
"reactive hydrophilic component" or "hydrophilic (polymeric)
crosslinker") of the hemostatic composition according to the
present invention is a hydrophilic crosslinker which is able to
react with its reactive groups once the hemostatic composition is
applied to a patient (e.g. to a wound of a patient or another place
where the patient is in need of a hemostatic activity). Therefore
it is important for the present invention that the reactive groups
of the polymeric component are reactive when applied to the
patient. It is therefore necessary to manufacture the hemostatic
composition according to the present invention so that the reactive
groups of the polymeric component which should react once they are
applied to a wound are retained during the manufacturing
process.
[0034] This can be done in various ways. For example, usual
hydrophilic polymeric components have reactive groups which are
susceptible to hydrolysis after contact with water. Accordingly,
premature contact with water or aqueous liquids has to be prevented
before administration of the hemostatic composition to the patient,
especially during manufacture. However, processing of the
hydrophilic polymeric component during manufacturing may be
possible also in an aqueous medium at conditions where the
reactions of the reactive groups are inhibited (e.g. at a low pH).
If the hydrophilic polymeric components can be melted, the melted
hydrophilic polymeric components can be sprayed or printed onto the
matrix of the biopolymer. It is also possible to mix a dry form
(e.g. a powder) of the hydrophilic polymeric component with a dry
form of the biocompatible polymer suitable for use in hemostasis.
If necessary, then an increase of the temperature can be applied to
melt the sprinkled hydrophilic polymeric component to the
biocompatible polymer suitable for use in hemostasis to achieve a
permanent coating of the hemostatic composition. Alternatively,
these hydrophilic polymeric components can be taken up into inert
organic solvents (inert vis-a-vis the reactive groups of the
hydrophilic polymeric components) and brought onto the matrix of
the biomaterial. Examples of such organic solvents are dry ethanol,
dry acetone or dry dichloromethane (which are e.g. inert for
hydrophilic polymeric components, such as NHS-ester substituted
PEGs).
[0035] The term "one hydrophilic polymeric component comprising
reactive groups" means that the presence of a second or further
hydrophilic polymeric component with nucleophilic reactive groups
is excluded in a hemostatic composition according to the present
invention.
[0036] In a preferred embodiment the hydrophilic polymer component
is a single hydrophilic polymer component and is a polyalkylene
oxide polymer, preferably a PEG comprising polymer. The reactive
groups of this reactive polymer are preferably electrophilic
groups.
[0037] The reactive hydrophilic component may be a
multi-electrophilic polyalkylene oxide polymer, e.g, a
multi-electrophilic PEG. The reactive hydrophilic component can
include two or more electrophilic groups, preferably a PEG
comprising two or more reactive groups selected from
succinimidylesters (--CON(COCH.sub.2).sub.2), aldehydes (--CHO) and
isocyanates (--N.dbd.C.dbd.O), e.g, a component as disclosed in the
WO2008/016983 A (incorporated herein by reference in its entirety)
and one of the components of the commercially available ones under
the trademark CoSeal.RTM..
[0038] Preferred electrophilic groups of the hydrophilic polymeric
crosslinker according to the present invention are groups reactive
to the amino-, carboxy-, thiol- and hydroxy-groups of proteins, or
mixtures thereof.
[0039] Preferred amino group-specific reactive groups are NHS-ester
groups, imidoester groups, aldehyde-groups, carboxy-groups in the
presence of carbodiimides, isocyanates, or THPP
(beta-[Tris(hydroxymethyl)phosphino] propionic acid), especially
preferred is Pentaerythritolpoly(ethyleneglycol)ether
tetrasuccinimidyl glutarate (=Pentaerythritol
tetrakis[1-1'-oxo-5'-succinimidylpentanoate-2-poly-oxoethyleneglycole]eth-
er (=an NHS-PEG with MW 10,000).
[0040] Preferred carboxy-group specific reactive groups are
amino-groups in the presence of carbodiimides.
[0041] Preferred thiol group-specific reactive groups are
maleimides or haloacetyls.
[0042] Preferred hydroxy group-specific reactive group is the
isocyanate group. The reactive groups on the hydrophilic
crosslinker may be identical (homofunctional) or different
(heterofunctional). The hydrophilic polymeric component can have
two reactive groups (homobifunctional or heterobifunctional) or
more (homo/hetero-trifunctional or more).
[0043] In special embodiments the material is a synthetic polymer,
preferably comprising PEG. The polymer can be a derivative of PEG
comprising active side groups suitable for crosslinking and
adherence to a tissue.
[0044] By the reactive groups the hydrophilic reactive polymer has
the ability to crosslink blood proteins and also tissue surface
proteins. Crosslinking to the biomaterial is also possible.
[0045] The multi-electrophilic polyalkylene oxide may include two
or more succinimidyl groups. The multi-electrophilic polyalkylene
oxide may include two or more maleimidyl groups.
[0046] Preferably, the multi-electrophilic polyalkylene oxide is a
polyethylene glycol or a derivative thereof.
[0047] In a most preferred embodiment the hydrophilic polymeric
component is pentaerythritolpoly(ethyleneglycol)ether
tetrasuccinimidyl glutarate (.dbd.COH102, also pentaerythritol
tetrakis[1-1'-oxo-5'-succinimidylpentanoate-2-poly-oxoethyleneglycole]eth-
er).
[0048] The hydrophilic polymeric component is a hydrophilic
crosslinker. According to a preferred embodiment, this crosslinker
has more than two reactive groups for crosslinking ("arms"), for
example three, four, five, six, seven, eight, or more arms with
reactive groups for crosslinking. For example, NHS-PEG-NHS is an
effective hydrophilic crosslinker according to the present
invention. However, for some embodiments, a 4-arm polymer (e.g.
4-arms-p-NP-PEG) may be more preferred; based on the same
rationale, an 8-arm polymer (e.g. 8-arms-NHS-PEG) may even be more
preferred for those embodiments where multi-reactive crosslinking
is beneficial. Moreover, the hydrophilic crosslinker according to
the present invention is a polymer, i.e. a large molecule
(macromolecule) composed of repeating structural units which are
typically connected by covalent chemical bonds. The hydrophilic
polymer component according to the present invention should have a
molecular weight of at least 1000 Da (to properly serve as
crosslinker in the hemostatic composition according to the present
invention); preferably the crosslinking polymers according to the
present invention has a molecular weight of at least 5000 Da,
especially of at least 8000 Da.
[0049] For some hydrophilic crosslinkers, the presence of basic
reaction conditions (e.g. at the administration site) is preferred
or necessary for functional performance (e.g. for a faster
crosslinking reaction at the administration site). For example,
carbonate or bicarbonate ions (e.g. as a buffer with a pH of 7.6 or
above, preferably of 8.0 or above, especially of 8.3 and above) may
be additionally provided at the site of administration (e.g. as a
buffer solution or as a fabric or pad soaked with such a buffer),
so as to allow an improved performance of the hemostatic
composition according to the present invention or to allow
efficient use as a hemostatic and/or wound adherent material.
[0050] The reactivity of the hydrophilic polymeric component
(which, as mentioned, acts as a crosslinker) in the composition
according to the present invention is retained in the composition.
This means that the reactive groups of the crosslinker have not yet
reacted with the hemostatic composition and are not hydrolyzed by
water (or at least not in a significant amount which has negative
consequences on the hemostatic functionality of the present
compositions). This can be achieved by combining the hemostatic
polymer with the hydrophilic crosslinker in a way which does not
lead to reaction of the reactive groups of the crosslinker with the
hemostatic polymer or with water. Usually, this includes the
omitting of aqueous conditions (or wetting), especially wetting
without the presence of acidic conditions (if crosslinkers are not
reactive under acidic conditions). This allows the provision of
reactive hemostatic materials.
[0051] According to a specifically preferred hemostatic composition
of the invention, the biocompatible polymer is crosslinked gelatin
and the hydrophilic polymeric component is
pentaerythritolpoly(ethyleneglycol)ether tetrasuccinimidyl
glutarate.
[0052] Preferred ratios of the biocompatible polymer to hydrophilic
polymeric component in the hemostatic composition according to the
present invention are from 0.1 to 50% w/w, preferably from 5 to 40%
w/w.
[0053] The hemostatic compositions according to the present
invention are preferably provided as dry composition, e.g. as a
physical mixture, of the hemostatic polymer and the hydrophilic
reactive component, wherein the biocompatible polymer and the
hydrophilic polymeric component are present in dry form, preferably
in mixed dry form. "Mixed" according to the present invention
includes powder mixing, coating, impregnating, blending,
agglomerating, co-lyophilizing, drying from suspension, subsequent
or concurrent co-filling, co-extruding, etc.
[0054] A "dry" hemostatic composition according to the present
invention has only a residual content of moisture which may
approximately correspond to the moisture content of comparable
available products, such as Floseal.RTM. (Floseal, for example, has
about 12% moisture as a dry product). Usually, the dry composition
according to the present invention has a residual moisture content
below these products, preferably below 10% moisture, more preferred
below 5% moisture, more preferred below 2.5%, especially below 1%
moisture. The hemostatic composition according to the present
invention can also have lower moisture content, e.g. 0.1% or even
below. Preferred moisture contents of the dry hemostatic
composition according to the present invention are 0.1 to 10%,
especially 0.5 to 5%. It is clear that the dryer the composition
is, the longer their shelf life is and the lower is the risk that
the hemostatic properties of the composition as a whole suffer.
[0055] As already stated, the biocompatible polymer in particulate
form suitable for use in hemostasis is preferably gelatin in powder
form, especially wherein the powder particles have a median
particle size of 10 to 1000 .mu.m, preferably from 50 to 750 .mu.m,
more preferred from 150 to 700 .mu.m, especially from 150 to 500
.mu.m.
[0056] Further components may be present in the hemostatic
composition according to the present invention. According to
preferred embodiments, the hemostatic compositions according to the
present invention may further comprise a substance selected from
the group consisting of antifibrinolytic, procoagulant, platelet
activator, antibiotic, vasoconstrictor, dye, growth factors, bone
morphogenetic proteins and pain killers.
[0057] The hemostatic composition according to the present
invention may comprise a further composition of gelatin and a
polyvalent nucelophilic substance, preferably human serum albumin,
optionally at a basic pH (e.g. pH 8 to 11, preferably 9 to 10,
especially at a pH of 9.5). The 2 components may then be co-applied
to an injury.
[0058] According to another aspect, the present invention relates
to the use of a hemostatic composition according to the present
invention for the treatment of an injury selected from the group
consisting of a wound, a hemorrhage, damaged tissue, bleeding
tissue and/or bone defect.
[0059] The present invention also relates to a method of treating
an injury selected from the group consisting of a wound, a
hemorrhage, damaged tissue and/or bleeding tissue comprising
administering a hemostatic composition according to the present
invention to the site of injury.
[0060] According to another aspect, the present invention provides
a kit for the treatment of an injury selected from the group
consisting of a wound, a hemorrhage, damaged tissue and/or bleeding
tissue comprising [0061] a) a hemostatic composition according to
the present invention; and [0062] b) instructions for use
[0063] The present invention also relates to a method for producing
a hemostatic composition according to the present invention
comprising the step of mixing, a biocompatible polymer suitable for
use in hemostasis and one hydrophilic polymeric component
comprising reactive groups in dry form.
[0064] It is preferred to provide the hemostatic compositions
according to the present invention in dry form in an administration
container, preferably in a syringe, optionally together with a
pharmaceutically acceptable diluent.
[0065] These hemostatic compositions according to the present
invention may be reconstituted to "ready-to-use" hemostatic
preparations using pharmaceutically acceptable diluents (e.g.
aqueous ionic solutions). Preferably, the "ready-to use"
preparations are present or provided as hydrogels. Products of this
kind are known in principle in the art, yet in a different format.
Usually, the components are provided as separate entities in dry
form. Before mixing the components for administration to a patient,
the dry components are usually contacted separately with
pharmaceutically acceptable diluents. Mixing of the components is
then performed by mixing the separately reconstituted
components.
[0066] For stability reasons, such products (as well as the
products according to the present invention) are usually provided
in a dry form and brought into the "ready-to-use" form (which is
usually in the form of a (hydro-)gel, suspension or solution)
immediately before use, necessitating the addition of wetting or
solvation (suspension) agents.
[0067] According to the present invention, the hemostatic
composition is provided in dry form in the final container. In the
dry form, degradation or inactivation processes for the components
are significantly and appropriately reduced to enable storage
stability.
[0068] The dry hemostatic compositions according to the present
invention are usually reconstituted (re-hydrated) before use by
contacting the dry composition with a pharmaceutically acceptable
diluent. Such a pharmaceutically acceptable diluent may be part of
the kit according to the present invention (together with the
hemostatic composition). The diluent according to the present
invention may be any suitable reconstitution medium
("reconstitution solution" or "re-hydration medium") for the dry
hemostatic composition which allows suitable wetting of the dry
composition. Preferably, the dry hemostatic composition is
reconstituted into a hydrogel as a "ready-to-use" format.
[0069] Suitable diluents are pharmaceutically acceptable aqueous
fluids, e.g. pharmaceutical grade de-ionized water (if all ionic or
buffer components are already provided in the dry composition;
"water-for-injection") or pharmaceutical grade aqueous solutions
containing specific ions and/or buffers. Preferably, the diluent
comprises a substance selected from the group consisting of NaCl,
CaCl.sub.2 and sodium acetate (or, of course, mixtures
thereof).
[0070] For example, a suitable diluent comprises water for
injection, and--independently of each other--50 to 200 mM NaCl
(preferably 150 mM), 10 to 80 mM CaCl.sub.2 (preferably 40 mM) and
1 to 50 mM sodium acetate (preferably 20 mM). Preferably, the
diluent can also include a buffer or buffer system so as to buffer
the pH of the reconstituted dry composition, preferably at a pH of
3.0 to 10.0, more preferred of 6.4 to 7.5, especially at a pH of
8.9 to 7.1.
[0071] According to a preferred embodiment, the diluent further
comprises thrombin, preferably 10 to 1000 I.U. thrombin/ml,
especially 250 to 700 I.U. thrombin/ml. Preferably, the hemostatic
composition in this ready to use form contains 10 to 100,000
International Units (I.U.) of thrombin, more preferred 100 to
10,000 I.U., especially 500 to 5,000 I.U. The thrombin
concentration in the ready-to-use composition is preferably in the
range of 10 to 10,000 I.U., more preferred of 50 to 5,000 I.U.,
especially of 100 to 1,000 I.U./ml. The diluent is used in an
amount to achieve the desired end-concentration in the ready-to-use
composition. The thrombin preparation may contain other useful
component, such as ions, buffers, excipients, stabilizers, etc.
[0072] These aqueous diluents may further contain other
ingredients, such as excipients. An "excipient" is an inert
substance which is added to the solution, e.g. to ensure that
thrombin retains its chemical stability and biological activity
upon storage (or sterilization (e.g. by irradiation)), or for
aesthetic reasons e.g. color. Preferred excipients include human
albumin and sodium acetate. Preferred concentrations of human
albumin in the reconstituted product are from 0.1 to 100 mg/ml,
preferably from 1 to 10 mg/m. Preferred sodium acetate
concentrations are in the range of from 1 to 10 mg/ml, especially 2
to 5 mg/ml.
[0073] Preferably, the thrombin preparation contains human albumin.
Preferred salts are NaCl and/or CaCl.sub.2, both used in the usual
amounts and concentrations applied for thrombin (e.g. 0.5 to 1.5%
NaCl (e.g. 0.9%) and/or 20 to 80 mM CaCl.sub.2 (e.g. 40 mM)).
[0074] In a preferred embodiment, the pharmaceutically acceptable
diluent is provided In a separate container. This can preferably be
a syringe. The diluent in the syringe can then easily be applied to
the final container for reconstitution of the dry hemostatic
compositions according to the present invention. If the final
container is also a syringe, both syringes can be finished together
in a pack. It is therefore preferred to provide the dry hemostatic
compositions according to the present invention in a syringe which
is finished with a diluent syringe with a pharmaceutically
acceptable diluent for reconstituting said dry and stable
hemostatic composition.
[0075] According to a preferred embodiment, the final container
further contains an amount of a stabilizer effective to inhibit
modification of the polymer when exposed to the sterilizing
radiation, preferably ascorbic acid, sodium ascorbate, other salts
of ascorbic acid, or an antioxidant.
[0076] According to another aspect, the present invention also
provides a method for delivering a hemostatic composition according
to the invention to a target site in a patient's body, said method
comprising delivering a hemostatic composition produced by the
process according to the present invention to the target site.
Although in certain embodiments, also the dry composition can be
directly applied to the target site (and, optionally be contacted
with the diluent a the target site, if necessary), it is preferred
to contact the dry hemostatic composition with a pharmaceutically
acceptable diluent before administration to the target site, so as
to obtain a hemostatic composition in a wetted form, especially a
hydrogel form.
[0077] The present invention also refers to a finished final
container obtained by the process according to the present
invention. This finished container contains the combined components
in a sterile, storage-stable and marketable form. The final
container can be any container suitable for housing (and storing)
pharmaceutically administrable compounds. Syringes, vials, tubes,
etc. can be used; however, providing the hemostatic compositions
according to the present invention in a syringe is specifically
preferred. Syringes have been a preferred administration means for
hemostatic compositions as disclosed in the prior art also because
of the handling advantages of syringes in medical practice. The
compositions may then preferably be applied (after reconstitution)
via specific needles of the syringe or via suitable catheters. The
reconstituted hemostatic compositions (which are preferably
reconstituted to form a hydrogel) may also be applied by various
other means e.g. by a spatula, a brush, a spray, manually by
pressure, or by any other conventional technique. Administration of
the reconstituted hemostatic composition to a patient by spraying
is specifically preferred. Usually, the reconstituted hemostatic
compositions according to the present invention will be applied
using a syringe or similar applicator capable of extruding the
reconstituted composition through an orifice, aperture, needle,
tube, or other passage to form a bead, layer, or similar portion of
material. Mechanical disruption of the compositions can be
performed by extrusion through an orifice in the syringe or other
applicator, typically having a size in the range from 0.01 mm to
5.0 mm, preferably 0.5 mm to 2.5 mm. Preferably, however, the
hemostatic composition will be initially prepared from a dry form
having a desired particle size (which upon reconstitution,
especially by hydration, yields subunits of the requisite size
(e.g. hydrogel subunits)) or will be partially or entirely
mechanically disrupted to the requisite size prior to a final
extrusion or other application step. It is, of course evident, that
these mechanical components have to be provided in sterile form
(inside and outside) in order to fulfill safety requirements for
human use.
[0078] Another aspect of the invention concerns a method for
providing a ready-to-use hemostatic composition comprising
contacting a hemostatic composition produced by the process
according to the present invention with a pharmaceutically
acceptable diluent.
[0079] The present invention also concerns a kit comprising the dry
and stable hemostatic composition according to the present
invention in finished form and a container with a suitable diluent.
Further components of the kit may be instructions for use,
administration means, such as syringes, catheters, brushes, etc.
(if the compositions are not already provided in the administration
means) or other components necessary for use in medical (surgical)
practice, such as substitute needles or catheters, extra vials or
further wound cover means. Preferably, the kit according to the
present invention comprises a syringe housing the dry and stable
hemostatic composition and a syringe containing the diluent (or
provided to take up the diluent from another diluent container).
Preferably, these two syringes are provided in a form adapted to
each other so that the diluent can be delivered to the dry
hemostatic composition by another entry than the outlet for
administering the reconstituted composition.
[0080] Therefore, a method for providing a ready to use form of a
hemostatic composition according to the present invention, wherein
the hemostatic composition is provided in a first syringe and a
diluent for reconstitution is provided in a second syringe, the
first and the second syringe are connected to each other, and the
diluent is brought into the first syringe to produce a flowable
form of the hemostatic composition; and optionally returning the
flowable form of the hemostatic composition to the second syringe
at least once, is a preferred embodiment of the present invention.
This process (also referred to as "swooshing") provides a suitable
"ready-to-use" form of the compositions according to the present
invention which can easily and efficiently be made also within
short times, eg. in emergency situations during surgery. This
flowable form of the hemostatic composition provided by such a
method is specifically suitable for use in the treatment of an
injury selected from the group consisting of a wound, a hemorrhage,
damaged tissue, bleeding tissue and/or bone defects.
[0081] The invention is further described in the examples below and
the drawing figures, yet without being restricted thereto.
[0082] FIG. 1 shows crosslinked gelatin mixed with 20 wt % of
NHS-PEG hydrated with saline solution at neutral pH (Example 1) in
a liver punch lesion model 5 min post application.
EXAMPLES
Example 1
Mixture Neutral
[0083] A mixture was prepared by mixing a specific amount of
crosslinked gelatin particles with 20 wt % of NHS-PEG. Typically,
6g of gelatin particles in a 50 ml test tube were mixed with 1.2 g
of NHS-PEG using end-over-end-mixer for at least 30 minutes in
order to obtain a homogenous mixture of both components. From the
mixture obtained, 0.96 g were weighted in a 5 ml syringe. As a
diluent 3.5 ml of saline solution in a 5 ml syringe with female
luer connector were used to hydrate the powder component before
application to a bleeding site.
[0084] Hydration of the particulate component with the diluent was
achieved by connection of both syringes and transforming the
diluent to the syringe filled with the gelatin. In order to obtain
a homogenous product, the content of the syringes was pushed back
and forth at least 21 times. After hydration, a product obtained
was allowed to hydrate for 2 minutes. A product obtained was
applied to a bleeding wound using appropriate applicator tip
attached to the syringe with a male luer.
Example 2
Mixture Basic
[0085] In order to obtain a faster reactive flowable hemostat the
mixture as described in Example 1 was hydrated by using 3.5 ml of a
basic buffer having pH of 9.5 as a diluent.
[0086] A product obtained was allowed to hydrate for 2 minutes and
was applied to a blending wound.
Example 3
Mixture Acidic
[0087] In order to obtain a reactive flowable hemostat with
prolonged stability the mixture as described in Example 1 was
hydrated with 3.5 ml of saline solution having pH adjusted to 1.5
with 1 M of HCl as a diluent.
[0088] A product obtained was allowed to hydrate for 2 minutes and
was applied to a bleeding wound.
Example 4
In Vivo Study
[0089] A preparation of Example 1 was tested for hemostatic
efficacy on heparinized animal (pig) in a punch or biopsy liver
lesion. Each lesion in the series was topically treated with the
product applied from the syringe through applicator tip. Moistened
gauze was used to help approximate the test product to the lesion
and the timer was started. A saline moistened approximation gauze
was removed after 30 seconds and the degree of bleeding was
assessed at 30 seconds, 1, 2, 5 and 10 minutes after the test
articles were applied. Product saturated with blood but without
active bleeding was scored as 0. Saline solution was used to
irrigate the excess test articles away from the lesions after the 5
minutes assessment. Performance of selected formulations at 5
minutes assessment is shown in FIG. 1.
[0090] All patent filings, scientific journals, books, treatises,
and other publications and materials discussed in this application
are hereby incorporated by reference for all purposes. While
exemplary embodiments have been described in some detail, by way of
example and for clarity of understanding, those of skill in the art
will recognize that a variety of modification, adaptations, and
changes may be employed. Hence, the scope of the present invention
should be limited solely by the claims.
* * * * *