CN120897736A

CN120897736A - Powder composition comprising a haemostat

Info

Publication number: CN120897736A
Application number: CN202480022895.0A
Authority: CN
Inventors: X·加里克; G·伊瑟曼; E·加托伊拉特; M·费朗
Original assignee: French National Montpellier Institute Of Advanced Chemistry; Womeide Co; Centre National de la Recherche Scientifique CNRS; Universite de Montpellier
Current assignee: French National Montpellier Institute Of Advanced Chemistry; Womeide Co; Centre National de la Recherche Scientifique CNRS; Universite de Montpellier
Priority date: 2023-04-04
Filing date: 2024-04-03
Publication date: 2025-11-04
Also published as: WO2024208882A1

Abstract

The invention relates to a powder composition comprising a specific degradable A and B block copolymer, at least one lubricant and at least one haemostat. The powder composition according to the invention is particularly suitable for use in a method of preventing and/or treating bleeding, preferably uterine bleeding. The invention also relates to a kit comprising (i) the powder composition of the invention, and (ii) a device for inserting the powder composition into a body cavity, preferably the uterine cavity.

Description

Powder composition comprising a haemostat

Technical Field

The present invention relates to a powder composition comprising a haemostat and the use of said powder composition in a method of preventing and/or treating bleeding, preferably uterine bleeding.

Background

Acute severe genital bleeding (or uterine bleeding) refers to excessive or persistent bleeding that is responsible for the uterus and is not associated with pregnancy, requiring urgent intervention. Uterine bleeding is generally classified according to its relationship to menstruation. Menorrhagia is upper genital bleeding that occurs simultaneously with menstruation, but with abnormal bleeding volume or duration. Uterine bleeding refers to bleeding of the upper genitalia that occurs outside of the menstrual period. It may be caused mainly by endometrial or myometrial lesions (hyperplasia, cancer, polyps, myomas of the uterus, adenomyopathies of the uterus). Menorrhagia is an emergency condition and is considered to be accidental uterine bleeding. Menorrhagia (i.e., the combination of menorrhagia and uterine bleeding) refers to uterine bleeding, which is not caused by a tumor, infection, or pregnancy.

Uterine bleeding is a common clinical problem and a source of pain for patients, as it can be life threatening. In fact, uterine bleeding is one of the leading causes of maternal mortality. Therefore, once bleeding occurs, it should be controlled as soon as possible.

A common treatment for uterine bleeding in emergency rooms is first intravenous injection of high doses of conjugated estrogens to regenerate the endometrium, covering the exposed areas of the bleeding source. Intravenous estrogen alone can stop bleeding, but is effective only 5 hours after the first administration. Conjugated estrogens can cause nausea and vomiting. This is the only treatment approved by the FDA specifically for the treatment of acute severe uterine bleeding. Anti-fibrinolytic agents may also be prescribed and used and are effective for timely administration within 3 hours of the onset of bleeding. Hemostatic effects typically appear within 2-3 hours after administration. A rare but serious side effect is the possibility of secondary venous thrombosis. Another approach is to use a device, typically in the form of a balloon, to tamponade the blood. These devices are invasive and can require several hours of placement, thus requiring the patient to lie in bed throughout the treatment in the emergency room. Removal of the balloon requires the patient to receive further medical intervention.

Thus, there is a definite need for an intrauterine system that can be easily introduced into the uterine cavity and that is capable of rapid and uniform release of hemostatic agents.

Disclosure of Invention

Against this background, the inventors have found that by using as a vehicle a copolymer in powder form and based on blocks of a polyester, such as polylactic acid (PLA), and blocks of high molecular weight poly (ethylene oxide) (PEO), a haemostat can be advantageously delivered into a body cavity, in particular the uterine cavity. In particular, such powder copolymers can produce materials that combine dispersive, blood absorbing and resorbing properties, which are particularly useful in uterine cavities to treat uterine bleeding. The inventors have thus developed a powder composition comprising a haemostat which is easy to introduce into a body cavity, such as the uterine cavity, has a good and uniform dispersibility, and advantageously releases the haemostat directly onto the body cavity wall, in particular the uterine wall. The powder composition of the present invention can cover the entire body cavity, particularly the uterine cavity (particularly the body cavity wall), and maintain the hemostatic effect for at least 24 hours. Furthermore, the powder composition of the present invention does not adhere to surrounding tissues and does not stimulate cell proliferation.

The powder composition of the present invention has the advantage of better coverage of the body cavity, particularly the uterine cavity, compared to a similar system in the form of a film, since the particles and haemostat can be dispersed throughout. As shown by the experimental data described in the examples section, the powder set faster than the film. The powder composition is also suitable for use in body cavities of all shapes and sizes and is easy to inject into the body cavity. More particularly, such powder compositions are suitable for use in uteri of all shapes and sizes and are easy to inject into the uterine cavity.

The powder composition according to the invention allows a very rapid release of the hemostatic agent from the moment of application to the body cavity, in particular the uterine cavity. In particular, the release of the hemostatic agent may begin directly after the system is applied to a body cavity, particularly the uterine cavity. Notably, for example, greater than 60% of the hemostatic agent originally present in the material may be released within 5 minutes after its administration. Furthermore, the material of the powder composition preferably has anti-adhesion properties and the uterine wall is kept separate by the intrauterine system, so that post-hemostatic scarring does not create intrauterine adhesions or adhesions. Finally, the disintegration and emptying times of the intrauterine system according to the present invention are typically 1-30 days, which not only allows the intrauterine system to remain in the uterine cavity long enough to treat bleeding, but also ensures its natural discharge, in particular before or during the next menstrual cycle.

Accordingly, one object of the present invention is a powder composition comprising:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The weight average molecular weight of the block B is greater than or equal to 50kDa and

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one lubricant, and

-At least one haemostat.

Another object is a powder composition according to the invention for administration of a hemostatic agent into a body cavity, preferably a uterine cavity.

Another object is a powder composition according to the invention for use in a method of preventing and/or treating bleeding, preferably uterine bleeding.

Another object is a powder composition of the invention for use in a method of preventing and/or treating bleeding, wherein the composition is for administration into a body cavity of a subject.

Another object is a powder composition of the invention for use in a method of preventing and/or treating uterine bleeding, wherein the composition is for administration into the uterine cavity of a subject.

Another object of the invention is a kit comprising:

(i) The powder composition of the invention is preferably present in an amount of 500mg to 1000mg, and

(Ii) Means for inserting said powder into a body cavity, preferably the uterine cavity.

Drawings

Fig. 1 shows microscopic observations of powder triblock ABA, dried (left panel) and 10 minutes after water contact (right panel) to demonstrate its swelling properties. Images were taken with a Leica microscope, objective x 4. Scale bar 1000 μm.

Fig. 2 shows microscopic observations of the powder triblock ABA, dried (left panel) and 30 seconds after water contact (right panel) to demonstrate its swelling properties. Images were taken with a Leica microscope, objective x 10. Scale bar 400 μm.

Figure 3 shows the results of an in vitro release assay in which the percentage of thrombin released over time of a powder composition is measured using an ELISA method.

The clotting times of the different prototypes (prototype) obtained after the in vitro clotting test are shown in fig. 4. Prototypes included similar systems in powder and film form with different amounts of thrombin.

Figures 5 and 6 show the results of an in vitro haemostatic test comparing different powder compositions based on clotting time.

The results of in vivo studies (wounds created on pig livers) are shown in figures 7 and 8, where changes in wound bleeding level over time are observed. The efficacy of the different powder prototypes was evaluated.

The clotting times of the prototypes G0-G6 obtained after the in vitro clotting test are shown in FIG. 9. The prototype included powders of different lubricants mixed with the triblock and calcium alginate.

Detailed Description

The inventors have developed powder compositions comprising hemostatic agents having mechanical and chemical properties particularly suitable for use in the medical field, particularly for the treatment of bleeding, such as uterine bleeding. In particular, the dispersion and coverage properties of the copolymer used to prepare the powder composition, in combination with the haemostatic agent, allow for a reliable and rapid treatment of bleeding, such as uterine bleeding.

Definition of the definition

In the context of the present invention, the expression "x-y" is meant to include the values x and y.

The terms "molecular mass" and "molecular weight" are used interchangeably in the context of the present invention, unless otherwise indicated, to refer to weight average molecular weight (Mw). According to the invention, mw is determined by size exclusion chromatography using a polyethylene glycol calibration range, with dimethylformamide as the analytical solvent.

According to the invention, an "aqueous medium" refers to a medium having an osmotic pressure similar to that of a biological fluid. Phosphate Buffered Saline (PBS) is typically used as the aqueous medium and is considered to be representative of biological fluids.

According to the invention, "wet medium" refers to a medium equivalent to an aqueous medium, i.e. a medium having an osmotic pressure similar to that of a biological fluid, but which is not a liquid. The uterine cavity may be characterized as a non-liquid wet medium.

Powder composition

One subject of the present invention is a powder composition comprising:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one lubricant, and

-At least one haemostat.

According to the present invention, the term "polyester" means any polymer whose backbone repeating units contain ester functional groups and which can be used in the medical field. It is noted that polyester is understood to mean aliphatic polyesters such as poly (lactic acid) (PLA), poly (glycolic acid) (PGA), polycaprolactone (PCL), poly (lactic-co-glycolic acid) (PLGA), poly-butyrolactone (PBL), polyhydroxyalkanoates (PHA) and copolymers thereof.

In a preferred embodiment, the polyester (a block) is selected from the group consisting of poly (lactic acid) (PLA), poly (glycolic acid) (PGA), polycaprolactone (PCL), and copolymers thereof. Preferably, the polyester of the a block is selected from PLA and PCL.

Preferably, the polyester is in a non-crosslinked form.

The poly (lactic acid) (PLA) may be poly (L-lactic acid), poly (D-lactic acid) or poly (D, L-lactic acid). Advantageously, poly (D, L-lactic acid) (PDLLA) is used. In this case, the polymer preferably comprises at least 50mol% of L-lactic acid, and may in particular comprise at least 60%, 70%, 75%, 80%, 85%, 90%, 95% or 99% of L-lactic acid. Specifically, by varying the percentage of L-lactic acid relative to D-lactic acid, the rate of degradation of the A and B block copolymers can be varied. An increase in the content of L-lactic acid can slow down the degradation rate of the copolymer. In certain embodiments of the invention, the composition comprises 100% PLLA as the a block.

In the context of the present invention, poly (ethylene oxide) (PEO) is typically a linear polyether prepared from ethylene oxide or ethylene glycol monomers, preferably ethylene oxide monomers. Thus, according to the invention, the B block may also be a polyethylene glycol (PEG) having a high molecular weight of greater than or equal to 50kDa, in particular having a molecular weight as defined below.

According to the invention, the poly (ethylene oxide) (PEO) used for the B block has a high molecular weight such that the total molecular weight of PEO in the copolymer is greater than or equal to 50kDa.

Advantageously, the total molecular weight of PEO in the A and B block copolymers is from 50kDa to 300kDa. For example, the molecular weight of the PEO block is 50kDa、75kDa、80kDa、85kDa、90kDa、95kDa、100kDa、105kDa、110kDa、115kDa、120kDa、125kDa、150kDa、200kDa、225kDa、250kDa、275kDa or 300kDa. In a particular embodiment, PEO blocks are used having a molecular weight of 75kDa to 150kDa, preferably 80kDa to 125kDa, more preferably 90kDa to 115kDa, more preferably 90kDa to 110kDa. In a particular embodiment, PEO blocks are used having a molecular weight of 95kDa to 105kDa.

According to the invention, the intrinsic viscosity of the PEO blocks used in the A and B block copolymers is advantageously from 0.04mg/ml to 0.6mg/ml, preferably from 0.08mg/ml to 0.5mg/ml, and more preferably from 0.1mg/ml to 0.3mg/ml, when measured with a Ubbelohde capillary viscometer at 25℃at a concentration of 1 g/l.

Advantageously, the a and B block copolymers are selected from AB diblock copolymers, or ABA or BAB triblock copolymers, or mixtures thereof, in particular [ ABA and BAB ], [ AB and ABA ], [ AB and BAB ], [ ABA and BAB and AB ]. In a preferred embodiment, the a and B block copolymers are selected from ABA or BAB triblock copolymers, preferably ABA triblock copolymers.

According to the invention, in the AB and/or ABA copolymer, the molecular weight of each PEO block (B block) is greater than or equal to 50kDa and advantageously comprised between 50kDa and 300kDa, preferably comprised between 75kDa and 150kDa, preferably comprised between 80kDa and 125kDa, more preferably comprised between 90kDa and 115kDa, more preferably comprised between 90kDa and 110kDa, or even comprised between 95kDa and 105kDa, whereas in the BAB copolymer the sum of the molecular weights of the PEO blocks in the copolymer is greater than or equal to 50kDa and advantageously comprised between 50kDa and 300kDa, preferably comprised between 75kDa and 150kDa, preferably comprised between 80kDa and 125kDa, more preferably comprised between 90kDa and 115kDa, more preferably comprised between 90kDa and 110kDa, or even comprised between 95kDa and 105kDa.

In the context of the present invention, the molar ratio means the molar ratio of each repeating unit (or units) of blocks a and B. When block B is PEO, the repeat units are ethylene oxide ("ethylene oxide units" or EO), while the repeat units of block a ("ester units") are carboxylic acid units, such as lactic acid units. According to the invention, the molar ratio of EO/ester units in the degradable A and B block copolymers is from 0.5 to 5, preferably from 1 to 3. The molar ratio is measured by proton NMR (nuclear magnetic resonance) spectroscopy of the copolymer in deuterated chloroform, wherein the chemical shift of the characteristic peak of the PLA-PEO-PLA copolymer can be identified as CH (PLA) 5.1ppm and CH ₂(PEO)：3.5ppm;CH₃ (PLA) 1.5 ppm. According to the present invention, controlling the EO/LA ratio allows controlling the dispersion and blood absorption characteristics and degradation time of the powder composition. In general, the lower the EO/LA ratio, the longer the degradation time.

In a particular embodiment of the invention, the molar ratio of EO/ester units in the degradable A and B block copolymers is from 0.5 to 3, or from 0.5 to 2, or from 0.5 to 1.6, or from 0.8 to 3, or from 0.8 to 2, or from 0.8 to 1.6, or from 1 to 3, or from 1 to 2, or from 1 to 1.6.

In a particular embodiment, the degradable A and B block copolymers consist of ABA triblock copolymers wherein block A is PDLLA and block B is PEO having a molecular weight of 90kDa to 110kDa with an EO/LA molar ratio of 0.8 to 2.

In a particular embodiment, the degradable a and B block copolymers consist of ABA triblock copolymers wherein block a is PDLLA and block B is PEO having a molecular weight of 90kDa to 110kDa, with an EO/LA molar ratio of 1.56.

In a particular embodiment, the degradable a and B block copolymers consist of ABA triblock copolymers wherein block a is PDLLA and block B is PEO having a molecular weight of 90kDa to 110kDa, wherein the EO/LA molar ratio is 1.

In a particular embodiment, the degradable a and B block copolymers consist of ABA triblock copolymers wherein block a is PDLLA and block B is PEO having a molecular weight of 90kDa to 110kDa, wherein the EO/LA molar ratio is 2.

In another particular embodiment, the degradable A and B block copolymers consist of ABA triblock copolymers wherein block A is PDLLA and block B is PEO having a molecular weight of 90kDa to 110kDa, wherein the molar ratio EO/LA is 3.

In the context of the present invention, the degradable A and B block copolymers are in powder form, preferably having a particle size of 50 μm to 500. Mu.m, more preferably 150 μm to 500. Mu.m, measured by sieving. According to the present invention, controlling the particle size of the degradable A and B block copolymers can control the dispersion and coverage characteristics of the powder composition. In general, the lower the particle size of the A and B block copolymers, the better the dispersion and coverage characteristics. However, if the particle size is too small, for example below 50 μm, the powder may have a greater tendency to compact, making insertion into the cavity difficult. Conversely, if the particle size is too high, for example in excess of 500 μm, the different components of the powder will be more difficult to mix, and furthermore, the surface importance of the coverage decreases for the same amount of powder. Advantageously, the degradable A and B block copolymers are in powder form, the particle size of which is 50μm-500μm、80μm-500μm、100μm-500μm、120μm-500μm、125μm-500μm、150μm-500μm、200μm-500μm、250μm-250μm、125μm-250μm、50μm-450μm、50μm-400μm、50μm-350μm、50μm-300μm、50μm-250μm or 50 μm to 200 μm as measured by sieving. More advantageously, the degradable A and B block copolymers are in the form of powders having a particle size of 120 μm to 500. Mu.m, preferably 125 μm to 500. Mu.m, more preferably 125 μm to 250 μm or 250 μm to 500. Mu.m. Typically, the degradable A and B block copolymers are in powder form with particle sizes of 125 μm to 250 μm or 250 μm to 500 μm. According to the invention, the particle size of the A and B block copolymers can be measured by methods known to the person skilled in the art, for example by sieving, laser diffraction, dynamic light scattering or image analysis methods. Typically, particle size can be measured by sieving.

The a and B block copolymers according to the invention may be obtained by any method known to the person skilled in the art for the synthesis of block copolymers. For example, ABA copolymers can be obtained from the end of block B by chain polymerization. Generally, lactide ring-opening polymerization initiated by the terminal hydroxyl groups of the PEO blocks is carried out in the presence of a catalyst such as tin octoate. The polymerization can be carried out with or without a solvent. For example, BAB-type copolymers can be prepared by coupling methoxy-PEO onto PLA chains, both chain ends of which are carboxylic acid functional groups. Such "difunctional" PLA can be obtained, for example, by treating the PLA chain with succinic anhydride or adipic anhydride.

In the context of the present invention, the powder composition advantageously comprises 59% to 99.94%, preferably 60% to 99.94%, preferably 59% to 99.44%, preferably 60% to 99.44%, preferably 67.5% to 98.99% of the a and B block copolymers, based on the total weight of the powder composition. For example, the powder composition may comprise 59% to 99%, or 59% to 98%, or 59% to 95%, or 59% to 90%, or 59% to 89%, or 59% to 88%, or 59% to 85%, or 59% to 80%, or 59% to 75%, or 59% to 70%, or 99% to 99.94%, or 98% to 99.94%, or 95% to 99.94%, or 90% to 99.94%, or 89% to 99.94%, or 88% to 99.94%, or 85% to 99.94%, or 80% to 99.94%, or 75% to 99.94%, or 70% to 99.94% by mass of the a and B block copolymer relative to the total mass of the powder composition.

In the context of the present invention, the powder composition further comprises a lubricant. Advantageously, the powder composition comprises 0.5% -5% of lubricant by total mass of the powder composition. In particular, the powder composition may comprise 0.5% to 5%, or 0.5% to 4.5%, or 0.5% to 4%, or 0.5% to 3.5%, or 0.5% to 3%, or 1% to 5%, or 1% to 4.5%, or 1% to 4%, or 1% to 3.5%, or 1% to 3% by mass of lubricant based on the total mass of the powder composition. Advantageously, the powder composition comprises 1% -3% by mass of lubricant, based on the total mass of the powder composition. For example, the powder composition may comprise 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5% by mass of lubricant relative to the total mass of the powder composition. Advantageously, the lubricant is selected from the group consisting of magnesium stearate, stearic acid, sodium stearyl fumarate, micronized polyethylene glycol (micronized polyethylene glycol 6000), leucine, talc, sodium benzoate and mixtures thereof. Preferably, the lubricant is magnesium stearate. The lubricant is preferably in powder form and may be mixed with the other components of the powder composition using any method known to those skilled in the art. The addition of a lubricant to the powder composition reduces friction and avoids sticking to the inner surface of the insertion device and ensures regular flow during injection in the uterus.

In another particular aspect of the invention, the powder composition of the invention may be free of lubricants. In this embodiment, for example, injection of the powder composition into the uterine cavity may be facilitated by improved particle size determination of the degradable a and B block copolymers in the powder composition.

For example, another object of the invention may be a powder composition comprising:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one hemostatic agent, and

-Optionally, at least one lubricant.

In particular embodiments, the powder composition may comprise:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one hemostatic agent, and

Optionally, at least one lubricant,

Wherein the degradable A and B block copolymers are in powder form and have a particle size of 120 μm to 500. Mu.m, preferably 125 μm to 500. Mu.m, more preferably 125 μm to 250 μm or 250 μm to 500. Mu.m.

In a particular embodiment, the powder composition is free of lubricant. Thus, the lubricant-free powder composition may comprise 60% to 99.9999% of the a and B block copolymers, and 0.0001% to 40% of the hemostatic agent, relative to the total mass of the powder composition.

In another particular embodiment, the powder composition comprises:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of ethylene oxide units/ester units is from 0.8 to 2, preferably from 0.8 to 1.6, more preferably from greater than 1 to 1.6;

At least one hemostatic agent, and

-Optionally, at least one lubricant.

In this embodiment, the degradable A and B block copolymers are advantageously in powder form with particle sizes of 120 μm to 500. Mu.m, preferably 125 μm to 500. Mu.m, more preferably 125 μm to 250 μm or 250 μm to 500. Mu.m.

In the context of the present invention, the powder composition further comprises a haemostat, preferably in powder form. Hemostatic agents are active ingredients that promote blood clotting and prevent blood flow. The haemostat of the invention is advantageously selected from the group consisting of thrombin, calcium alginate, carboxymethylated starch, calcium salts such as calcium chloride, carboxymethyl cellulose, gelatin, calcium ions, tranexamic acid, collagen, fibrinogen and oxidized cellulose. Advantageously, the haemostat according to the invention is selected from the group consisting of thrombin, calcium alginate, carboxymethylated starch and calcium chloride. In a preferred embodiment, the hemostatic agent is thrombin. In another preferred embodiment, the hemostatic agent is calcium alginate.

The amount of hemostatic agent in the powder composition depends on the hemostatic agent selected. In general, the powder composition according to the invention advantageously comprises 0.0001% to 40% by mass, preferably 0.0001% to 39.5% by mass, preferably 0.0001% to 30% by mass, of haemostatic agent, preferably in powder form, relative to the total mass of the powder composition.

In a particular embodiment, when the haemostatic agent is thrombin, it is advantageously present in the powder composition in an amount of from 0.0001% to 1%, preferably from 0.0001% to 0.1%, preferably from 0.001% to 0.1%, more particularly from 0.005% to 0.05%.

In another particular embodiment, when the haemostatic agent is calcium alginate or carboxymethylated starch, its content in the powder composition is advantageously from 5% to 40%, preferably from 8% to 40%, preferably from 5% to 39.5%, preferably from 8% to 32%, or from 20% to 30%, or from 25% to 30% by mass relative to the total mass of the powder composition.

In another particular embodiment, when the haemostatic agent is calcium chloride, its content in the powder composition is advantageously comprised between 0.01% and 5% by mass, preferably between 0.1% and 5% by mass, preferably between 0.5% and 5% by mass, preferably between 1% and 4% by mass, preferably between 1% and 3% by mass, preferably 2% by mass, relative to the total mass of the powder composition.

In a particular embodiment, the powder composition according to the invention may also comprise a carrier for the haemostat, also called filler. Advantageously, the powder composition comprises 0% to 40% of carrier by total mass of the powder composition. In particular, the powder composition may comprise 0% to 40%, or 0% to 39.5%, or 1% to 40%, or 5% to 30%, or 5% to 20%, or 7% to 19%, or 8% to 40%,10% to 40%, or 10% to 35% by mass of the carrier, based on the total mass of the powder composition. Advantageously, the powder composition comprises 5% -30% by mass of carrier, based on the total mass of the powder composition. For example, the powder composition may comprise 0%, 5%, 7%, 8%, 10%, 15%, 19%, 20%, 25%, 30%, 35%, 40% by mass of carrier relative to the total mass of the powder composition. Advantageously, the carrier is selected from the group consisting of lactose, carboxymethylated starch, polyethylene glycol (PEG), poly (ethylene oxide) (PEO) and carboxymethyl cellulose. Preferably, the carrier is lactose or carboxymethylated starch. The addition of a carrier for the hemostatic agent to the powder composition may improve the dispersion and uniformity of the powder composition and the dispersibility of the hemostatic agent, thereby accelerating the contact of the powder composition of the present invention with the uterine cavity wall. The mixing of the hemostatic agent with the carrier may be performed by any method known to those skilled in the art, for example by dissolving the hemostatic agent in a carrier solution, followed by drying or lyophilization.

In a particular embodiment, the powder composition according to the invention comprises, by mass, relative to the total mass of the powder composition:

-59% -99.44% of a degradable a and B block copolymer;

0.5% -5% of a lubricant,

From 0.0001% to 1% of thrombin, and

-0% -39.5% Carrier.

-94.9999% -99.44% of a degradable a and B block copolymer;

0.5% -5% of a lubricant,

-0.0001% -1% Thrombin.

-80% -90% of a degradable a and B block copolymer;

-1% -3% of a lubricant,

-From 0.0001% to 0.1% thrombin, and

-7% -19% Carrier.

-80% -90% of a degradable a and B block copolymer;

-1% -3% of a lubricant,

0.5% -3% Of calcium chloride, and

-7% -19% Carrier.

-67% -89% of a degradable a and B block copolymer;

-1% -3% of a lubricant,

8% -32% Of calcium alginate.

-67% -89% of a degradable a and B block copolymer;

-1% -3% of a lubricant,

8% -32% Of carboxymethylated starch.

In another particular aspect, the powder composition according to the invention comprises, by mass, relative to the total mass of the powder composition:

-59% -99.44% of a degradable a and B block copolymer in powder form, having a particle size of 250 μm-500 μm;

-0% -5% of a lubricant,

From 0.0001% to 1% of thrombin, and

-0% -39.5% Carrier.

-94.9999% -99.44% of a degradable a and B block copolymer in powder form, having a particle size of 250 μm-500 μm;

-0% -5% of a lubricant,

-0.0001% -1% Thrombin.

80% -90% of a degradable A and B block copolymer in powder form, having a particle size of 250 μm to 500 μm;

-0% -3% of a lubricant,

-From 0.0001% to 0.1% thrombin, and

-7% -19% Carrier.

-0% -3% of a lubricant,

0.5% -3% Of calcium chloride, and

-7% -19% Carrier.

67% -89% of a degradable a and B block copolymer in powder form, having a particle size of 250 μm to 500 μm;

-0% -3% of a lubricant,

8% -32% Of calcium alginate.

-0% -3% of a lubricant,

8% -32% Of carboxymethylated starch.

Specific examples of the powder composition of the present invention may be:

97.97% ABA triblock copolymer+0.03% thrombin+2% magnesium stearate, or

-68.5% ABA triblock copolymer + 0.03% thrombin + 29.97% carboxymethylated starch + 1.5% magnesium stearate, or

-68% ABA triblock copolymer + 30% carboxymethylated starch + 2% magnesium stearate, or

-68.25% ABA triblock copolymer + 29.25% calcium alginate + 2.5% magnesium stearate, or

95.5% ABA triblock copolymer+2% CaCl ₂ +2.5% magnesium stearate, or

-79% ABA triblock copolymer+18% lactose+2% CaCl ₂ +1% magnesium stearate, or

85% ABA triblock copolymer+15% calcium alginate in powder form with particle size of 250 μm to 500 μm.

In a particular embodiment, the powder composition according to the invention comprises only degradable a and B block copolymers, a lubricant, a haemostat and optionally a carrier for the haemostat. In a particular embodiment, the powder composition according to the invention consists of a degradable A and B block copolymer, a lubricant, a haemostat and optionally a carrier for the haemostat. In another particular embodiment, the powder composition according to the invention consists of a degradable A and B block copolymer in powder form having a particle size of 250 μm to 500 μm, a haemostat and optionally a carrier for the haemostat.

In another particular embodiment, the powder composition according to the invention may also comprise other additives or active ingredients, such as therapeutic molecules such as antibiotics or vasoconstrictors. Such additives or active ingredients may be added to the composition, for example, in powder form, for dispersion in the powder composition. Preferably, the other active ingredient is capable of diffusing out of the material when the material is in an aqueous or wet medium. For example, the other active ingredient may be a vasoconstrictor.

The preparation of the powder composition according to the invention can be carried out by any method known to the person skilled in the art, and in particular by mixing each of the ingredients into powder form. Other methods for preparing the powder composition of the invention may be, for example, spray drying, granulation, preferably wet granulation, physical mixing, or dissolution/precipitation in a non-solvent with stirring.

In the context of the present invention, the powder composition according to the invention advantageously can release at least 30% of the initially present haemostatic agent within 10 minutes or less after introduction of the powder composition according to the invention into a body cavity, preferably the uterine cavity. In particular, the powder composition according to the invention advantageously allows to release at least 30% of the initially present haemostatic agent into a body cavity, in particular a uterine cavity, within less than 8 minutes, 6 minutes, 5 minutes, 4 minutes, 3 minutes, 2 minutes or 1 minute (including the limits) after introduction of the powder composition according to the invention into the body cavity, preferably the uterine cavity.

Advantageously, the powder composition according to the invention may release at least 50%, preferably at least 60% of the initially present haemostatic agent into a body cavity, in particular a uterine cavity, within 10 minutes or less after introduction of the powder composition according to the invention into the body cavity, preferably the uterine cavity. In particular, the powder composition according to the invention advantageously allows to release at least 50%, preferably at least 60% of the initially present haemostatic agent into a body cavity, in particular a uterine cavity, within less than 8 minutes, 6 minutes, 5 minutes, 4 minutes, 3 minutes (including the limits) after introduction of the powder composition according to the invention into the body cavity, preferably the uterine cavity.

Advantageously, the powder composition according to the invention may release at least 80%, preferably at least 90% of the initially present haemostatic agent into a body cavity, in particular a uterine cavity, within 10 minutes or less after introduction of the powder composition according to the invention into the body cavity, preferably the uterine cavity. In particular, the powder composition according to the invention advantageously allows to release at least 80%, preferably at least 90% of the initially present haemostatic agent into a body cavity, in particular a uterine cavity, in less than 10 minutes, 9 minutes or 8 minutes after introduction of the powder composition according to the invention into the body cavity, preferably the uterine cavity.

In a preferred embodiment, after introduction of the powder composition according to the invention into a body cavity, preferably a uterine cavity, the powder composition according to the invention advantageously can release the following into the body cavity, in particular the uterine cavity:

-releasing at least 30% of the initially present haemostat in 8 minutes or less;

releasing at least 50% of the initially present haemostatic agent in 10 minutes or less, and/or

-Releasing at least 80% of the initially present haemostat in 30 minutes or less;

-releasing at least 50% of the initially present haemostat in 6 minutes or less;

releasing at least 60% of the initially present haemostatic agent in 10 minutes or less, and/or

-releasing at least 30% of the initially present haemostat in 1 minute or less;

-releasing at least 60% of the initially present haemostatic agent in 5 minutes or less, and/or

-Releasing at least 80% of the initially present haemostat in 10 minutes or less;

in the context of the present invention, the release profile of a hemostatic agent into a body cavity, in particular into the uterine cavity, is measured according to an ELISA (enzyme-linked immunosorbent assay) method.

In the context of the present invention, a rapid release of the hemostatic agent onto the wall of a body cavity, in particular onto the wall of a uterus, enables a rapid and effective treatment of bleeding, in particular uterine bleeding.

Another particularly advantageous feature of the powder composition according to the invention, which is applied in the uterine cavity, is that it has anti-adhesive properties. After hemostasis is achieved, a scarring process follows and may cause the two walls of the uterus to join together in the form of an adhesive or cohesive fibrous bridge. The powder composition with anti-blocking properties allows for the formation of a physical and mechanical barrier between the walls and thus allows scarring without blocking.

Another particularly advantageous feature of the powder composition according to the invention is that it is degradable in an aqueous or wet medium. In particular, the powder composition according to the invention is degraded after a residence time in the body cavity, in particular in the uterine cavity, of from 2 hours to 30 days, preferably from 12 hours to 20 days, more preferably from 1 to 15 days. The degradation of the powder composition is due to progressive hydrolysis of the ester bonds of the polyester blocks, followed by dissolution of the PEO-containing blocks. The loss of mechanical properties of the material is directly related to its degradation. Degradation can be assessed by measuring the decrease in molecular weight over time of a strip of material immersed in saline medium (PBS 1X) at 37 ℃ and stirred, for example by size exclusion chromatography. The reduction in dynamic viscosity of the material can also be assessed. Thus, the degradation properties of the powder composition according to the invention may be such that the powder composition remains intact in a body cavity, in particular the uterine cavity, for a time sufficient to treat bleeding, in particular uterine bleeding, and then degrade sufficiently to enable its natural discharge.

In the context of the present invention, the powder composition may be regarded as a degradable system for releasing hemostatic agents into a body cavity. In particular, the powder composition may be regarded as a degradable intrauterine system for releasing hemostatic agents into the uterine cavity.

Use of the powder composition of the invention

Another object of the present invention is a powder composition as defined above for administration of a hemostatic agent into a body cavity, preferably the uterine cavity.

Another object of the present invention is a powder composition as defined above for use in a method of preventing and/or treating bleeding, preferably uterine bleeding.

Another object of the present invention is a powder composition as defined above for use in a method of preventing and/or treating bleeding, wherein the composition is for administration in a body cavity of a subject.

Another object of the present invention is a powder composition as defined above for use in a method of preventing and/or treating uterine bleeding, wherein the composition is for administration in the uterine cavity of a subject.

Another object of the present invention is a method for preventing and/or treating bleeding in a subject, comprising the step of administering a powder composition as defined above into a body cavity to be treated of a subject in need thereof.

Another object of the present invention is a method for preventing and/or treating uterine bleeding in a subject, comprising the step of administering a powder composition as defined above into the uterine cavity of a subject in need thereof.

A further object of the present invention is the use of a powder composition as defined above for the preparation of a medicament for use in a method of preventing and/or treating bleeding, preferably uterine bleeding. In particular, the composition is for administration into a body cavity of a subject, in particular a uterine cavity.

In the context of the present invention, bleeding refers to an acute blood loss from a damaged vessel. Bleeding can occur in any part of the body, particularly in mammalian, preferably human, bodies. Common sources of bleeding include organ damage (liver, spleen, kidney, adrenal gland), vascular damage, complications of gynecological/obstetric surgery or coagulopathy. For example, the bleeding may be selected from the group consisting of uterine bleeding, hemothorax, abdominal bleeding, cerebral bleeding, organ bleeding (e.g., liver, spleen, kidney, adrenal gland), oral bleeding, nasal bleeding, rectal bleeding, vaginal bleeding, preferably uterine bleeding.

Kit for detecting a substance in a sample

Another object of the invention is a kit comprising (i) a powder composition of the invention as defined above, preferably in an amount of 500mg to 2000mg, and (ii) a device for inserting said powder composition into a body cavity. The kit according to the invention advantageously comprises means for inserting and placing materials into a body cavity.

Another object of the invention is a kit comprising (i) a powder composition of the invention as defined above, preferably in an amount of 500mg to 1000mg, and (ii) a device for inserting said powder composition into a body cavity, preferably the uterine cavity. The kit according to the invention advantageously comprises means for inserting and placing materials into a body cavity, in particular a uterine cavity.

The kit according to the invention advantageously comprises a pharmaceutically effective dose of the powder according to the invention. In a specific embodiment, the kit comprises a single dose of the powder of the invention. In another embodiment, the kit may comprise at least two doses of the powder of the invention.

For example, a kit according to the invention may comprise a hollow cylindrical inserter, the powder composition being contained in a tube thereof. Advantageously, in order to minimize the size of the inserter, the powder composition is contained in a compacted form in a tube. By "compacted form" is meant that the powder remains in a defined volume.

The kit advantageously comprises a plunger mounted on the distal end of the inserter in a translatable sliding manner, the opposite proximal end being the end through which the inserter is intended to be introduced into a body cavity, in particular the uterine cavity. The plunger comprises or consists of a rod that, when pushed into the bore of the inserter and proximally, drives the powder composition to translate towards the outside of the inserter.

Advantageously, the plunger is provided with stop means at the squeeze proximal end for abutting against the wall of the bore against the proximal end of the inserter to inform the kit operator that the powder composition has been completely expelled from the inserter and has entered the body cavity, in particular the uterine cavity. The insertion device/inserter assembly can then be removed by simply pulling outwardly.

Such a kit allows a powder composition according to the invention to be reliably introduced and uniformly dispersed in a body cavity, in particular a uterine cavity.

The kit according to the invention may be particularly suitable for patients suffering from uterine bleeding. The compacted form of the material and the use of small applicators make it easy to insert into the uterine cavity where these patients are often sensitive. Furthermore, the device is naturally expelled during the menstrual cycle without requiring additional intervention by medical personnel on the patient to remove the device.

The invention will be illustrated by the following examples. These embodiments are merely non-limiting examples of the present invention.

Examples

EXAMPLE 1 preparation of powder compositions according to the invention

1. Synthesis of ABA triblock copolymers

A. Material

Commercially available polyethylene oxide (PEO) Sigma-Aldrich, CAS No. 25322-68-3. Commercial PEO was analyzed by Size Exclusion Chromatography (SEC) in the laboratory to determine its weight average molar mass (Mw). The analysis was performed in an analysis solvent (dimethylformamide) and the Mw was determined using a poly (ethylene glycol) calibration range. The weight average molar mass Mw was 95000Da and the intrinsic viscosity thereof was 0.16ml/mg.

Commercial D, L-lactide, supplier Corbion Purac, CAS No. 95-96-5.

B. Method of

ABA triblock is synthesized by:

PEO (Mw 95000) (200 g) and D, L-lactide (458 g) were dried under vacuum at room temperature for 24 hours. PEO and D, L-lactide were introduced into a polymerization flask in the presence of tin octoate (85 mg). 10 successive cycles of vacuum (10 ^-3 bar) and argon inertization were then carried out. The mixture was then heated to 140 ℃ and 10 more successive cycles of vacuum and argon inertization were performed. The mixture was returned to room temperature and then placed in an ice bath. After crystallization, the reaction mixture was placed under dynamic vacuum for 30 minutes and then sealed under dynamic vacuum. The mixture was then placed in a mechanically rotating oven at 140 ℃ for 3 days. The mixture was dissolved in dichloromethane and precipitated from the ether/ethanol mixture. The precipitate was recovered and then dried in vacuo for 24 hours.

C. Characterization of

The final composition of the copolymer was determined by ¹ H NMR proton NMR and the EO/LA molar ratio was deduced to be 1. The molar ratio of ethylene oxide units (EO) to lactic acid units (La) was determined as EO/LA= [ peak area of EO unit methylene (3.5 ppm) per EO unit proton number ]/[ peak area of LA unit methine (5.1 ppm) per LA unit proton number ].

Two-dimensional NMR analysis (DOSY) showed that synthesis did produce ABA triblock (PLA 50-PEO-PLA 50).

The copolymers were also analyzed by Size Exclusion Chromatography (SEC) to determine their average molar mass Mw and their dispersity Ip.

Using an analytical solvent such as dimethylformamide and calibrating the range using poly (ethylene glycol), a Mw of 123000Da and a dispersity in the range of 5 are obtained.

Furthermore, thermogravimetric analysis (TGA) allows to determine the degradation temperature of the copolymer, which is 256 ℃.

2. Preparation of the powder composition according to the invention

A. Material

Human thrombin, lyophilized form, supplier SIGMA ALDRICH (CAS# 9002-04-4). The protein activity contained in the product analysis certificate is >400 NIH units/mg protein.

Triblock ABA powder prepared as described above (part 1) for use in compositions of powders A1-A4, B1-B5, C1-C5, D1-D3 and E1-E2.

Triblock ABA powder prepared as above (part 1), but with EO/LA molar ratio of 1.56, was used in the composition of powders G0-G6.

PEO, having an average molecular weight Mw of 100kDA, measured by SIGMA ALDRICH (CAS # 25322-68-3) -average particle size of about 150 μm.

Calcium alginate, sodium alginate salts of brown algae, alginate, sodium alginate, supplied by SIGMA ALDRICH (CAS # 9005-38-3) -particle size D _98% <160 μm.

CaCl ₂, anhydrous, granular, 7.0mm or less, 93.0% or more, supplied by SIGMA ALDRICH (CAS# 10043-52-4).

Lactose, white crystalline powder, provided by ArmorPharma (ref EXCIPRESS SD L).

Carboxymethylated starch, sodium starch glycolate, supplied by Roquette (ref GLYCOLYS) -particle size D _98% <105 μm.

Magnesium stearate, magnesium stearate salt, provided by SIGMA ALDRICH (CAS # 557-04-0).

Sodium stearyl fumarate, (E) -2-butene diacid mono-octadecyl ester sodium salt supplied from SIGMA ALDRICH (CAS# 4070-80-8).

Talc, a hydrated magnesium silicate powder, supplied by Cooper.

B. powder preparation

Powder comprising carrier and thrombin

The carrier was dissolved in a salt solution (pH 6.5-7.5) at room temperature with stirring. The lyophilized thrombin is then dissolved in the solution. The resulting carrier-thrombin solution was placed in a freeze-dryer at-52 ℃ and dried at 0.06 mbar for 16 hours.

The lyophilized carrier/thrombin mixture was then mixed with the triblock ABA powder (particle size of 125 μm-500 μm) and lubricant using a three-dimensional mixer. The ingredients and amounts are disclosed in table 1 below.

Powder containing hemostatic agent without carrier

Three-dimensional mixers were used to mix triblock ABA powder (particle size 125 μm-500 μm), hemostatic agent and lubricant. The ingredients and amounts are disclosed in table 1 below.

TABLE 1

Example 2 evaluation of swelling Properties of powder triblock ABA

At t=0, 500mg of triblock ABA prepared in example 1 was placed in a crystallizer, followed by addition of 30mL of water. The powder was placed in water for 10 minutes. Water is absorbed using a water absorbing paper and then the powder is recovered. The powder was weighed 1.49g at 10 minutes. The powder mass was almost three times the initial (200% mass increase).

Fig. 1 shows that at t=10 min the powder has swollen and the particles have agglomerated, compared to the powder at t=0 min.

One particle of triblock ABA was placed under a microscope, a photograph was taken at t=0, and then 10 μl of water was dropped onto the particle. After 30s a photograph was taken and the particles were observed for water absorption (fig. 2).

Powder surface was measured using software JmageJ (image-based scale) to evaluate surface increments of t=0 to t=30 seconds. The results were as follows:

Surface at t=0 71963 μm ²(0.072 mm²)

Surface at t=30s 91965 μm ²(0.092 mm²)

We increased 20 mm ² in 30 seconds, which means that the powder absorbed water.

EXAMPLE 3 evaluation of thrombin release kinetics

In vitro release method

The powder was placed in a 50ml vial containing 10ml phosphate buffer (pH 7.4). The vial was placed under mechanical stirring (87 rpm) at 37 ℃. 31 μl samples were collected at 30 seconds, 3 minutes, 5 minutes, and 10 minutes release after introduction. Each sample was analyzed using an enzyme-linked immunosorbent assay (ELISA). The amount of thrombin released per sampling time was calculated according to the calibration curve equation obtained for the standard range.

Method for measuring thrombin

The ELISA (Abcam supply; reference ab 270210) used was designed for quantitative measurement of thrombin. During the release assay, thrombin (analyte) present in the collected solution is captured by the capture antibody and by the detection antibody coupled to the reporter molecule, revealing the thrombin content present in the assay sample. The whole complex is then immobilized by the immunoaffinity of the anti-labeled antibody covering the well (capture antibody/analyte/detection antibody). The signal thus generated is proportional to the amount of analyte (thrombin) bound to the antibody complex. Signal intensity was measured at 450nm using an enzyme-labeled instrument.

Calculation method

A series of dilutions were made from thrombin stock (1689600 pg/mL) to obtain a concentration range of 0-8500 pg/mL. The Optical Density (OD) at 450nm was measured for each concentration, and a standard curve was drawn for the optical density as a function of thrombin concentration. The equation for this curve will determine the thrombin concentration of the unknown sample. Then, based on the amount of thrombin contained in the powder, we can evaluate the change in the percentage of thrombin released over time.

Powder composition

The powder used was the powder prototype A1 described in example 1.

Results

The calibration curve is linear (r2=0.98) over a concentration range of 0-8500 pg/mL. The concentration of thrombin in the solution released by powder A1 was determined using the same calibration curve. The percentage of thrombin released over time for A1 is shown in fig. 3 and table 2. Under in vitro release conditions, thrombin is released from the powder over time. The release of thrombin starts at about 30 seconds and at least 95% of the thrombin in the powder is released after 10 minutes.

TABLE 2

EXAMPLE 4 evaluation of hemostatic Properties (in vitro)

A. Materials and methods

Hemostatic support

Whole blood containing CPD (glucose phosphate citrate) is provided by Etablissement Fran ç sais du Sang. The blood must be recalcified before use in a clotting assay, for which calcium chloride (CaCl ₂ -CAS 10043-52-4-vendor Sigma-Aldrich) is added to the blood. For subsequent testing, 3mL CaCl ₂ (concentration 0.122: 0.122 mol/L) was added to 30mL whole blood.

In vitro model

30ML of CPD-containing whole blood (no recalcification) contained in 50mL of falcon was heated in a 37℃water bath for 30 minutes, and then the assay was started. After adding CaCl ₂, 10mL of recalcified blood was introduced into a plastic uterine cavity model (size: height 75mm; large base 45mm; small base 12 mm). The model was inverted (small base/opening portion up) to avoid blood loss during the test. The prototype powder to be tested is then inserted into the model using an inserter. The entire assembly was placed in an oven at 37 ℃.

Coagulation time measurement

The coagulation process was visually observed. Clotting time is the time for all blood in the uterine cavity model to coagulate. To determine this time, the model (containing blood and prototype) was rotated 180 ° per minute for the first 10 minutes, then once every 2 minutes until clotting was observed. The test was repeated three times and then the average clotting time was calculated.

Testing prototypes

Powder prototypes A1-A4, B1-B5 and C1-C5 for in vitro testing have been prepared using the methods described in example 1. The powder compositions are detailed in table 1 in example 1.

Comparative film prototypes F1 and F2 described below were obtained by preparing triblock ABA powder as described in example 1, followed by hot pressing to form a film by placing 2.5mg of the powder between two plates heated to 85 ℃ and pressing for 9 minutes at a pressure of 20 MPa. The obtained 500 μm thick film was then cut with a sample punch to obtain a film having a height of 25mm, a large substrate of 20mm, and a small substrate of 10mm.

● F1 the endometrium is impregnated with THR 100 NIH units. The composition is 99.984% triblock ABA and 0.016% pure thrombin.

● F2 THR coating of endometrial 100 NIH units. Composition 80% triblock ABA, 19.987% PEO and 0.013% pure thrombin.

B. Results

Comparison of b 1-powder prototypes A1-A4 with the endometrium F1 and F2

Fig. 4 shows clotting time (min) as a function of the test prototype.

The following observations can be made:

● The clotting time was shorter when blood was in contact with the test prototype than whole blood alone.

● The more thrombin units, the faster the clotting time (A1-100 units vs A2-200 units vs A3-400 units).

● The thrombin-containing powder mixture (A1, A2 and A3) had better clotting times than the thrombin-free powder mixture (A4).

● The clotting time of the powder mixture (A1) is better than that of the membranes (F1 and F2) for the same number of thrombin NIH units. We can assume that blood is partially absorbed by the powder and thrombin is released immediately from the powder, unlike film formation, where blood absorption is slower and thrombin release time is longer.

Comparison of B2-prototype B1-B5

Fig. 5 shows clotting time (min) as a function of the test prototype. The test prototypes included lactose or carboxymethylated starch as carriers.

The following observations can be made:

● It can be observed that the clotting time is shorter when blood is in contact with the test prototype than whole blood alone.

● The clotting times of the thrombin-containing powder mixtures (B1, B2, B4) are better than those of the thrombin-free powder mixtures (B3, B5).

● The more thrombin units, the faster the clotting time (B1-100 units vs B2-50 units).

● The clotting time of carboxymethylated starch with the triblock mixture (B5, thrombin-free) is better than that of lactose with the triblock mixture (B3, thrombin-free). When lactose and carboxymethylated starch were used as hemostatic carriers, no differences were observed between these identical prototypes containing thrombin (B1, B4).

Comparison of B3-prototype C1-C5

Fig. 6 shows clotting time (min) as a function of the test prototype. The test prototypes included different hemostatic agents mixed with triblock and magnesium stearate.

The following observations can be made:

● The powder mixture containing 100 NIH units of thrombin (C5) is superior to other powder mixtures.

● The clotting time of the triblock mixed with any hemostatic agent is superior to the clotting time of the triblock alone.

● Calcium-containing prototypes (C1, C2) have better clotting times than prototypes containing carboxymethylated starch (C3).

● The clotting time of the prototype containing calcium alginate (C1) was comparable to that of the prototype containing 50 NIH units of thrombin (C4).

EXAMPLE 5 hemostatic Performance assessment (in vivo)

I. Hemorrhage scale

The bleeding status prior to assessment was evaluated using a standardized semi-quantitative bleeding scale to determine an initial bleeding severity that could reflect clinical use. The bleeding scale will also be used throughout the trial to observe the progress of bleeding. The following scale:

0 = no bleeding

0.5 =Bleed (blood was observed at the edge, but not flowing)

1 = Very slight bleeding (very slow blood flow from the site)

2 = Slight (slow blood flow)

3 = Moderate (rapid blood flow, no pulsatile action)

4 = Severe (rapid blood flow, pulsation and ejection of wound)

The test is preferably grade 1-2 bleeding.

In vivo model

Pigs were selected for their anatomical dimensions and organ structure, which are similar to humans and also similar to humans in the coagulation system.

Cut on the pig liver so that the prototype can be inserted into the parenchyma. The hemostatic prototype will be in direct contact with the bleeding wound.

To obtain grade 1-2 bleeding, incision sizes of 1cm long and 0.5cm deep were used.

Hemostatic property determination

The bleeding level changes were observed to evaluate the hemostatic performance of the prototype (i.e., the ability to reduce the bleeding level).

When bleeding severity stabilized, the initial bleeding was scored about 1 minute after incision creation. The prototype was then inserted into the wound using a syringe. Once the prototype is in place, a timer is triggered. Hemostatic performance (bleeding level) was scored at 3 minimum time points (e.g., 1, 3, and 6 minutes) using the bleeding scale defined above. The test was stopped at 6 minutes.

Prototype preparation

Powder prototypes D1-D3 and E1-E2 have been prepared using the methods described in example 1 and are used in the amounts detailed in Table 1. The control experiment corresponds to the insertion of no prototype into the wound.

V. results

A. comparison of prototypes D1, D2 and D3

The results are summarized in fig. 7. A comparison of the initial bleeding level and the bleeding level at 6 minutes was performed to evaluate the hemostatic performance of the test prototype.

The following observations can be made:

● At 6 minutes, blood flow remained the same in the absence of thrombin (control test, D3).

● When the thrombin powder mixture is introduced into the wound, blood flow is reduced by half (D1), or bleeding is completely stopped (D2).

● For the same number of thrombin units (400 NIH units), higher doses of triblock ABA help reduce blood flow (D1 vs D2) by absorbing blood, by filling the entire wound, thereby promoting thrombin diffusion within the wound.

B. Comparison of prototypes E1 and E2

The results are summarized in fig. 8. The hemostatic performance of the test prototype was evaluated by comparing the initial bleeding level with the bleeding levels at 3 minutes and 6 minutes.

The following observations can be made:

● At 6 minutes, blood flow remained the same in the absence of hemostatic agent (control test).

● At 6 minutes, bleeding stopped when prototype E1 or E2 was introduced.

● Prototypes containing calcium alginate (E2) appeared to have better performance than prototypes containing CaCl ₂ (E1) with a faster cessation of blood flow (E2 had no bleeding at 3 minutes, while E1 had very slight bleeding at 3 minutes).

● Particle size measurement of powder E1 (250 μm-500 μm) differs from powder E2 (125 μm-250 μm) in that particle size may have an effect on bleeding reduction, and we can assume that the smaller the particle size, the larger the contact surface.

Example 6 evaluation of the Effect of granulometry of powders according to the invention

A. Materials and methods

Particle size measurement

Determination of the particle size of the triblock with a sieve the triblock powder was classified by particle size category using a vibrating column sieve. Fractions corresponding to different particle sizes were separated and used to prepare prototype powders.

Evaluation of ejection difficulty

500Mg of the powder prototype sample was introduced into a 4.5mm inner diameter tube and the operator performing the test would evaluate the difficulty of expelling the powder from the tube using a pusher (tube) with an outer diameter of 4.2.

The difficulty level is as follows:

● The powder is easily discharged from the tube without using force.

● The powder can be expelled from the tube with a slight effort.

● It is difficult to expel the powder from the tube with great effort.

● It is impossible that the powder cannot be discharged from the tube.

The duration of the insertion procedure was also measured.

Testing prototypes

Powder prototypes C1-C2 and E1-E2 for in vitro testing have been prepared using the methods described in example 1. The powder compositions are detailed in table 1 in example 1.

Powder prototypes E1 and C2 were prepared using triblock with particle sizes of 250 μm to 500 μm, while powder prototypes E2 and C1 were prepared using triblock with particle sizes of 125 μm to 250 μm.

B. Results

The results of the discharge test are detailed in table 3 below:

TABLE 3 Table 3

The following observations can be made:

● Without magnesium stearate (E1 and E2), the powder was more difficult to discharge from a 4.5mm inside diameter tube than with magnesium stearate (see C2 and C1), the lubricant made the powder easier to discharge.

● The higher the particle size (E1, C2), the easier the powder is to be discharged from the tube. We can assume that small particle powder compacts much more than large particle powder.

EXAMPLE 7 evaluation of the Effect of lubricants on hemostatic Properties (in vitro)

A materials and methods

Hemostatic support (see example 4)

In vitro model (see example 4)

Determination of clotting time (see example 4)

Testing prototypes

Powder prototypes G0-G6 for in vitro testing have been prepared using the method described in example 1. The powder compositions are detailed in table 1 in example 1. The particle size of the triblock (included in the powder prototype) was measured between 250 μm and 500 μm.

B. Results

Fig. 9 shows clotting time (min) as a function of the test prototype. The prototype included different lubricants mixed with the triblock and calcium alginate.

The following observations can be made:

● Whether or not the lubricant was added, the clotting time was the same for each test prototype, and we can conclude that the type and amount of lubricant added had no effect on clotting time.

Example 8 evaluation of powder particle size determination and Effect of Lubricant type

A. materials and methods

Particle size determination, see example 6

Discharge difficulty evaluation:

500mg of the powder prototype sample was introduced into a tube having an inner diameter of 4.6mm, and the operator performing the test would evaluate the difficulty of expelling the powder from the tube using a pusher (solid tube) having an outer diameter of 4.5 mm.

The difficulty level is as follows:

● The powder is easily discharged from the tube without using force.

● The powder can be expelled from the tube with a slight effort.

● It is difficult to expel the powder from the tube with great effort.

● It is impossible that the powder cannot be discharged from the tube.

The duration of the insertion procedure was also measured.

Testing prototypes

Powder prototypes G0-G6 have been prepared using the method described in example 1. The powder compositions are detailed in table 1 in example 1.

We will use particle-a particle sizes from 125 μm to less than 250 μm and particle-b particle sizes from 250 μm to 500 μm (inclusive) to distinguish the particle sizes of the powder formulations.

G0-a to G6-a were prepared using triblock with particle sizes of 125 μm to less than 250 μm, while powder prototypes G0-b to G6-b were prepared using triblock with particle sizes of 250 μm to 500 μm (inclusive).

Note that only the triblock granulometry distinguishes between prototypes G0-a and G0-b (and other samples G1-G6), which are identical in composition.

B. Results

The results of the discharge test are detailed in table 4 below:

table 4:

The following observations can be made:

● Without the lubricants (G0-a and G0-b), the powder was more difficult to discharge from the 4.5mm inner diameter tube than with the lubricants (G1-a to G6-a and G1-b to G6-b) which made the powder easier to discharge.

● The higher the particle size (G0-b to G6-b), the faster the powder is discharged from the tube.

● With the same lubricant content, no difference was observed between different types of lubricants, which were identical in character and which allowed easy expulsion of the powder from the tube (see G1-G3 and G4-G6).

● The more lubricant, the faster the powder is expelled from the tube (see G4-G6 and G1-G3).

● The particle size of the triblock and the percentage of lubricant are two factors that affect the ease and speed of powder discharge.

Claims

1. A powder composition comprising:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one lubricant, and

-At least one haemostat.

2. The powder composition according to claim 1, wherein the particle size of the degradable a and B block copolymers is 50-500 μm as measured by sieving.

3. The powder composition according to claim 1, wherein the particle size of the degradable a and B block copolymer is 120 μm to 500 μm, in particular 125 μm to 500 μm, preferably 250 μm to 500 μm, as measured by sieving.

4. A powder composition comprising:

-a degradable a and B block copolymer, wherein:

the A block is a polyester;

The B block is polyethylene oxide (PEO);

The molar ratio of the ethylene oxide units/ester units is 0.5-5;

At least one hemostatic agent, and

Optionally, at least one lubricant,

Wherein the degradable A and B block copolymers are in powder form with particle sizes of 120 μm to 500. Mu.m, in particular 125 μm to 500. Mu.m, preferably 250 μm to 500. Mu.m.

5. The powder composition of claim 4, wherein the powder composition is free of lubricant.

6. The powder composition according to any one of claims 1-5, wherein the haemostatic agent is selected from the group consisting of thrombin, calcium alginate, carboxymethylated starch, calcium salts such as calcium chloride, carboxymethyl cellulose, gelatin, calcium ions, tranexamic acid, collagen, fibrinogen and oxidized cellulose.

7. The powder composition according to any one of claims 1-4 and 6, wherein the lubricant is selected from the group consisting of magnesium stearate, stearic acid, sodium stearyl fumarate, micronized polyethylene glycol, leucine, talc, sodium benzoate, and mixtures thereof.

8. The powder composition according to any one of claims 1-4 and 6-7, comprising 0.5-5%, preferably 1-3% by weight of the lubricant, based on the total weight of the powder composition.

9. The powder composition according to any of claims 1-8, wherein the degradable a and B block copolymers are selected from AB diblock copolymers and ABA and BAB triblock copolymers and mixtures thereof, preferably the degradable a and B block copolymers are ABA and/or BAB triblock copolymers, more preferably ABA triblock copolymers.

10. The powder composition according to any one of claims 1-9, wherein the weight average molecular weight of block B of the a and B block copolymers is from 75kDa to 150kDa, preferably from 80 kDa to 125kDa, more preferably from 90kDa to 115kDa, more preferably from 90kDa to 110kDa.

11. The powder composition according to any one of claims 1-10, wherein the ratio of ethylene oxide units/ester units of the a and B block copolymers is 1-3.

12. The powder composition according to any one of claims 1-11, wherein block a of the a and B block copolymer is poly (lactic acid), in particular selected from poly (L-lactic acid), poly (D-lactic acid) and poly (D, L-lactic acid).

13. The powder composition according to any one of claims 1-12, comprising 59-99.94%, preferably 67.5-98.99% by weight of the degradable a and B block copolymers, based on the total weight of the powder composition.

14. The powder composition according to any one of claims 1-13, further comprising a carrier for the haemostat, preferably selected from the group consisting of lactose, carboxymethylated starch, polyethylene glycol (PEG), poly (ethylene oxide) (PEO) and carboxymethyl cellulose, preferably in an amount of 0-40% by weight, preferably 8-30% by weight, based on the total weight of the powder composition.

15. The powder composition according to any one of claims 1-14 for use in the administration of the haemostat into a body cavity, preferably the uterine cavity.

16. The powder composition according to any one of claims 1-14 for use in a method of preventing and/or treating bleeding, preferably uterine bleeding.

17. The powder composition according to any one of claims 1-14 for use in a method of preventing and/or treating uterine bleeding, wherein the composition is for administration into the uterine cavity of a subject.

18. A method of preventing and/or treating bleeding from a body cavity in a subject, comprising the step of administering a powder composition as defined in any one of claims 1-14 into the body cavity to be treated in a subject in need thereof.

19. A method of preventing and/or treating uterine bleeding in a subject in need thereof, comprising the step of administering a powder composition as defined in any of claims 1-14 into the uterine cavity to be treated of a subject in need thereof.

20. Use of a powder composition according to any one of claims 1-14 for the manufacture of a medicament for use in a method of preventing and/or treating bleeding, preferably uterine bleeding.

21. A kit comprising

(I) A powder composition as defined in any one of claims 1 to 14, preferably in an amount of 500mg to 1000mg, and

(Ii) Means for inserting said powder composition into a body cavity, preferably the uterine cavity.