Patent Application
20140220147
The present invention relates to the field of pharmaceutical compositions comprising factor VII as active ingredient.
Factor VII (FVII) is a vitamin K-dependent glycoprotein which, in its activated form (FVIIa), participates in the coagulation process by activating factor X and factor IX in the presence of calcium and of tissue factor. FVII is secreted in the form of a single peptide chain of 406 amino acid residues, the molecular mass of which is approximately 50 kDa. FVII comprises four distinct structural domains: the N-terminal γ-carboxylic (Gla) domain, two epidermal growth factor-like (EGF-like) domains and one serine protease domain. The activation of FVII to give FVIIa is characterized by cleavage of the Arg152-Ile153 (Arginine 152-Isoleucine 153) bond. FVIIa is therefore composed of a light chain of 152 amino acids, having a molecular mass of approximately 20 kDa, and of a heavy chain of 254 amino acids, having a molecular mass of approximately 30 kDa, linked to one another by a single disulphide bridge (Cysteine 135-Cysteine 262).
FVII/VIIa is used in the treatment of patients suffering from haemophilia, who exhibit a deficiency in factor VIII (haemophilia type A) or in factor IX (haemophilia type B), and also patients who exhibit other coagulation factor deficiencies, for example a hereditary FVII deficiency. FVII/VIIa is also recommended in the treatment of cerebral strokes.
Thus, FVII/FVIIa is used mainly for patient treatments over a very long period of time, which involves giving repeated injections at time intervals which are at most weekly. In practice, a majority of patients treated with factor VII receive two to three weekly injections of FVII/VIIa, which causes considerable inconvenience.
Relatively high doses of FVII/VIIa, and also frequent intravenous administrations, are necessary in order to achieve and preserve the desired therapeutic or prophylactic effect. This treatment therefore remains both restrictive for the patients and very expensive.
FVII/VIIa is also commonly administered to patients who must undergo a surgical procedure. Usually, a first administration of FVII/VIIa, termed “loading dose”, for example from 30 to 40 IU/kg, is carried out approximately one hour before the surgical act, and then one or more subsequent injections may be given during the surgical operation and, where appropriate, in the hours or days which follow the surgical operation, in order to maintain the plasma FVII/VIIa level within the accepted norms.
It has been shown that FVII/VIIa is a protein that is sensitive to proteolytic cleavage leading to the formation of many degradation products devoid of coagulant activity (atypical cleavages). Atypical cleavages can occur at various stages of the production process, but also during storage of FVII/VIIa. The degradation products have been observed both for plasma-derived FVII/VIIa, and also for FVII/VIIa produced by genetic recombination. Atypical cleavages can occur before the activation of FVII to give FVIIa, for example during the production and purification of FVII, during the activation step itself or during the purification and/or storage of the activated product (FVIIa).
In order to improve the quality of prophylactic and therapeutic treatments with FVII/FVIIa, it would be advantageous to be able to have pharmaceutical compositions allowing improved FVII/VIIa bioavailability, compared with the bioavailability of the FVII/VIIa of known pharmaceutical compositions. It would in particular be advantageous to have compositions in which the FVII/VIIa has great stability and is less susceptible to the various degradations than in the known compositions.
In particular, it will be advantageous to have FVII/VIIa formulations which make it possible to increase the stability of FVII/FVIIa over time in the organism, and to allow the controlled release of FVII/FVIIa over time, in such a way as to increase the gap between two injections, and thus (i) to improve the quality of life of the patients receiving a chronic treatment and (ii) to facilitate the work of practitioners at the time of a surgical operation, for example by reducing or avoiding the recourse to several injections of FVII/FVIIa during a surgical procedure.
Solutions have already been envisaged in the prior art for improving the bioavailability of FVII/VIIa, for instance encapsulation thereof in liposomes.
Pharmaceutical compositions have also been described in which the FVII/VIIa is non-covalently bound to colloidal particles comprising approximately 1 to 20% in mole of an amphipathic lipid derivatized with a biocompatible hydrophilic polymer. European patent N° EP 1 633 440 describes this type of pharmaceutical composition which comprises FVII/VIIa encapsulated in colloidal particles formed from “PEGylated” liposomes.
There is a need in the prior art for alternative or improved pharmaceutical compositions comprising FVII/FVIIa, compared with the known pharmaceutical compositions.
The present invention provides a pharmaceutical composition comprising factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of from histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group.
In the said block copolymer molecules, the hydrophilic polymer segment is covalently bound to the hydrophobic polymer segment.
As used herein, polyalkylene glycol is of the following formula (A):
H—[O—R]z-OH (A),
wherein:
In some embodiments, R consists of an ethyl group and z ranges from 200 to 300.
In some embodiments of said pharmaceutical composition, the polyalkylene glycol consists of a polyethylene glycol, preferably a polyethylene glycol having a molecular weight ranging from 10 kDa to 12 kDa.
In some embodiments of said pharmaceutical composition, the mass ratio between the factor VII and the copolymer ranges from 1:100 wt:wt to 50:100 wt:wt, preferably from 5:100 wt:wt to 20:100 wt:wt.
In some embodiments of said pharmaceutical composition, the factor VII is chosen from (i) a non-recombinant factor VII purified from plasma and (ii) a recombinant factor VII, where appropriate a recombinant factor VII modified with one or more substitutions or deletions of an amino acid.
The present invention also relates to a pharmaceutical composition comprising factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment and (ii) a hydrophobic polymer segment consisting of a polyamino acid, which composition, when it is administered parenterally, is suitable for generating a pharmacokinetic profile having one or more of the following characteristics:
The values of the MRT and CL should be obtained from seven-week-old rats of the Wistar strain.
As used herein, an AUC value of 10% or more higher than the AUC value of a comparative composition encompasses an AUC value that is 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, or more than 100% higher than the AUC value of the said comparative composition. It has been found that in some embodiments a pharmaceutical composition according to the invention has, for a given amount of FVII/FVIIa comprised therein, an AUC value of twice (100% higher) the AUC value of a comparative composition comprising the same given amount of FVII/FVIIa but in the absence of micelles.
The invention also relates to a factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group, for use thereof as a medicament.
This invention also relates to a factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group, for the treatment of coagulation disorders.
Surprisingly, it has been shown according to the invention that FVII/FVIIa may be successfully incorporated into micelles of a block copolymer comprising blocks of a specific type containing, in the said block copolymer molecule, a hydrophilic polymer segment and a hydrophobic polymer segment.
It is specified that in the said block copolymer molecule, the hydrophilic polymer segment is covalently bound to the hydrophobic polymer segment.
It has also been shown according to the invention that the incorporation of FVII/FVIIa into micelles of a copolymer comprising blocks of a specific type containing, in the said block copolymer molecule, a hydrophilic polymer segment and a hydrophobic polymer segment makes it possible to significantly increase the bioavailability of the FVII/FVIIa in vivo.
In particular, it has been shown in the examples that micelles of this copolymer comprising blocks of a specific type cause controlled release over time of the FVII/FVIIa initially incorporated, and efficiently protect the FVII/VIIa against degradation in the bloodstream.
The present invention provides a pharmaceutical composition comprising factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group.
As used herein, “a part” of said amino acid residues means that one amino acid residue or more of the said polyamino acid has a side chain which is substituted with a hydrophobic group. Preferably, the “part” of substituted amino acid residues ranges from more than 10% to less than 100% of the amino acid residues comprised in the said polyamino acid. In some embodiments, the “part” of substituted amino acide residues ranges from 40% to less than 100%, which includes from 70% to less than 100% of the amino acid residues comprised in the said polyamino acid.
Specific embodiments (i) of the hydrophilic segment consisting of a polyalkylene glycol and (ii) of the hydrophobic segment consisting of a polyamino acid are detailed below, with the description of the block copolymer of formula (I).
It is specified that, preferably, the hydrophobic polyamino acid segment consists of a poly-homo-amino acid chain consisting, for example, of residues of L-amino acids, of D-amino acids or of racemic mixtures thereof. The hydrophobic segment may consist of a polyamino acid chain chosen from a poly(aspartic acid), a poly(glutamic acid), a poly(histidine), a poly(lysine), a poly(aspartic acid ester), a poly(glutamic acid ester), a poly(histidine ester), a poly(lysine ester), a partial hydrolysate of poly(aspartic acid ester), a partial hydrolysate of poly(glutamic acid ester), a partial hydrolysate of poly(histidine ester), or else a partial hydrolysate of poly(lysine ester). The term “partial hydrolysate” of a poly(amino acid ester) is intended to mean that the poly(amino acid) is only partially esterified, i.e. fewer than all of the amino acid residues are esterified.
The hydrophobic segment of said block copolymer above preferably comprises a number of amino acid residues ranging from 10 to 100 amino acid residues, for example from 20 to 75 amino acid residues, which includes from 30 to 50 amino acid residues.
Preferably, in an amino acid ester residue that may be contained in the hydrophobic segment of a block copolymer as defined above, the amino acid residue is esterified with a hydrophobic group. Said hydrophobic group is preferably selected from the group consisting of an alkyl chain containing from 5 to 12 carbon atoms and a benzyl group. Preferably, said alkyl chain consists of an alkyl chain which is unsubstituted or else substituted with one or more alkyl chains containing from 1 to 3 carbon atoms.
It is specified that the general family of block copolymers which are used for the production of a pharmaceutical composition is known in the art. To the applicant's knowledge, these block copolymers have, however, never been tested for their ability to encapsulate protein molecules, a fortiori blood coagulation proteins.
It has been shown in the examples that the incorporation of FVII/VIIa into micelles of a block copolymer as defined above does not cause any detectable modification of this coagulation factor. It is shown in the examples that the amount of FVII/VIIa that is used as the starting material for incorporation into micelles of the block copolymer described herein is integrally found in the final pharmaceutical composition which is prepared. The inventors have also shown that, starting from a given amount of FVII/VIIa for preparing (i) a pharmaceutical composition wherein FVII/VIIa is incorporated in micelles of the block copolymer described herein and (ii) a comparative composition devoid of micelles of the said block copolymer, the same amount of FVII/VIIa is measured in each of the two compositions.
Furthermore, it has been shown in the examples that, for a given amount of FVII/FVIIa incorporated respectively (i) into a composition in the absence of micelles and (ii) into a composition comprising micelles of the block copolymer defined above, an overall in vivo bioavailability of a significantly greater amount of FVII/FVIIa is observed, as illustrated by the FVII/FVIIa blood concentration profiles with each of these two compositions.
In addition, it is shown in the examples that the amount of FVII/VIIa which is released in vivo by the compositions comprising the micelles of said block copolymer into which FVII/VIIa is incorporated, even 48 hours after the time of injection, is greater than the amount of FVII/VIIa which is released in vivo by the micelle-free compositions 6 hours after the time of injection.
According to yet another aspect, it is shown in the examples that the compositions of FVII/VIIa incorporated into micelles of the block copolymer defined above are characterized in vivo in particular by an area under the curve (AUC) value which is up to two and a half times greater than the AUC value measured for the corresponding micelle-free composition.
It is noted that the AUC values of the compositions of FVII/VIIa incorporated into micelles in accordance with the invention are greater than the AUC values obtained with other known technical solutions for encapsulating FVII/VIIa, for instance that described in European patent N° EP 1 633 440 (see the results of tables 5 and 6 of said document).
According to yet another aspect, a pharmaceutical composition of the invention comprising FVII/VIIa incorporated into micelles of said copolymer allows the FVII/FVIIa to be bioavailable in the bloodstream for an exceptionally long period of time, compared with the bioavailability time of the same composition free of micelles, since mean residence times (MRTs) which are up to ten times longer have been measured with the pharmaceutical compositions of the invention.
In addition, it has been shown in the examples that the FVII/VIIa present in the pharmaceutical compositions of the invention was eliminated from the bloodstream much more slowly than the FVII/VIIa present in the corresponding pharmaceutical compositions free of micelles, since FVII/VIIa clearance (CL) values which are almost one third and lower than with the micelle-free compositions are measured after administration of the pharmaceutical compositions of the invention.
In addition, the terminal half-life values of t1/2(β) for the FVII/VIIa in the bloodstream, obtained with the pharmaceutical compositions of the invention, are much greater than those observed for the corresponding compositions free of micelles.
It is added that the exceptional pharmacokinetic profiles which are obtained when the FVII/VIIa is incorporated into micelles of said block copolymer defined in the present description could not be foreseen by those skilled in the art, at least owing to the fact that the ability of micelles of this type (i) to incorporate a protein molecule, (ii) to protect it against modifications caused by its transport in the bloodstream and (iii) to release it over time in a nondegraded form and in large amounts, is disclosed for the first time in the present description.
A fortiori, those skilled in the art could not anticipate that a coagulation protein of a specific type, such as factor VII/VIIa, could be successfully incorporated into the types of micelles described herein, and then be released in vivo according to a pharmacokinetic profile compatible with the possibility of developing improved FVII/VIIa prophylactic or therapeutic treatments, in particular FVII/VIIa prophylactic or therapeutic treatments requiring a reduced number of injections for a given period of time.
The surprising and unforeseeable nature of the in vivo results obtained with the pharmaceutical compositions of FVII/FVIIa of the invention is particularly attested to by the fact that the micelles of said block copolymer as defined in the present description have proved to be completely incapable of providing a change in the pharmacokinetic profile of another coagulation factor, which has significant structural and functional similarities with FVII/VIIa, namely factor IX. It is in particular specified that factor FVII/VIIa and factor IX are both GLA-domain proteins.
More precisely, it is shown in the examples that the amounts of factor IX incorporated into the compositions comprising micelles of said block copolymer are, as for FVII/VIIa, comparable with those of factor IX incorporated into the corresponding micelle-free compositions.
However, the results of the examples also show that the profiles of change in respective plasma concentrations of factor IX incorporated into compositions comprising said micelles and into corresponding compositions free of micelles, are identical. These results mean that the micelles of said block copolymer are, with regard to factor IX, (i) either incapable of incorporating factor IX, (ii) or incapable of incorporating factor IX without degrading it, (iii) or incapable of protecting factor IX against the modifications that it may undergo in the bloodstream, (iv) or incapable of releasing the incorporated factor IX into the bloodstream, (v) or else exhibit a combination of at least two of the abovementioned inabilities.
In some embodiments of a pharmaceutical composition of the invention, said pharmaceutical composition comprises factor VII encapsulated in micelles formed from a copolymer of formula (I) below:
in which:
In the block copolymer of formula (I), “Ac” means an acetyl group.
In the block copolymer of formula (I) above, the hydrophilic segment is represented by the R1 group consisting of a polyalkylene glycol.
As used herein, polyalkylene glycol is of the following formula (A):
H—[O—R]z-OH (A),
wherein:
Preferably, R is an unsubstituted linear alkyl group.
In some embodiments, R consists of an ethyl group or a butyl group and z ranges from 200 to 300.
The polyalkylene glycol is advantageously chosen from a polyethylene glycol, i.e. group R of formula (A) means an ethyl group, and a polybutylene glycol, i.e. group R of formula (A) means a butyl group.
Preferably, R1 is a polyethylene glycol.
Advantageously, R1 is a polyalkylene glycol, e.g. a polyethylene glycol or a polybutylene glycol, having a molecular mass ranging from 5 kDa to 50 kDa, which includes a polyalkylene glycol having a molecular mass ranging from 8 kDa to 20 kDa, which also includes a polyalkylene glycol having a molecular mass ranging from 10 kDa to 12 kDa.
Preferably, R1 is a polyethylene glycol having a molecular mass ranging from 5 kDa to 50 kDa, which includes a polyethylene glycol having a molecular mass ranging from 8 kDa to 20 kDa, which also includes a polyethylene glycol having a molecular mass ranging from 10 kDa to 12 kDa.
The molecular mass of a polyethylene glycol is 44 m+62, m being an integer consisting of the number of ethylene glycol units in the polymer. A polyethylene glycol of 5 kDa consequently comprises approximately 113 glycol units (i.e. z=about 113). A polyethylene glycol of 8 kDa consequently comprises approximately 180 glycol units (i.e. z=about 180). A polyethylene glycol of 10 kDa consequently comprises approximately 227 glycol units. A polyethylene glycol of 12 kDa consequently comprises approximately 270 glycol units. A polyethylene glycol of 15 kDa consequently comprises approximately 338 glycol units. A polyethylene glycol of 20 kDa consequently comprises approximately 450 glycol units. A polyethylene glycol of 50 kDa consequently comprises approximately 1126 glycol units. It should be noted that the value of “x” is determined as a standard value with a numerical allowance industrially. Illustratively, for a “x” value of 40, the actual measurement value of “x” may range between 37 and 43.
The molecular masses of a polyalkylene glycol, including of a polyethylene glycol, are average molecular masses. In general, the size of a polyalkylene glycol, including of a polyethylene glycol, is defined in relation to its average molecular mass, owing to the fact that, in practice, the individual size of the polyethylene glycol molecules can vary slightly within the population of molecules of the polymer.
In the block copolymer of formula (I), the hydrophobic segment consists of a poly(glutamic acid), of which at least a part of the glutamine residues are esterified with a hydrophobic R2 group.
In some embodiments, the R2 group consists of an alkyl containing from 5 to 18 carbon atoms, which is unsubstituted or else substituted with one or more alkyls containing from 1 to 3 carbon atoms.
In some preferred embodiments, the R2 group consists of an alkyl chain containing from 8 to 12 carbon atoms.
R2 may consist of an unsubstituted alkyl chain containing 8 carbon atoms (octyl group).
In other embodiments, the R2 group consists of a benzyl group.
The hydrophobic segment of a block copolymer of formula (I) comprises “x” glutamic acid residues. x is an integer ranging from 10 to 100, which includes from 20 to 75, and which also includes from 30 to 60. The examples illustrate the use of a block copolymer of formula (I) for which x is equal to 40.
As already specified previously, a part of the amino acid residues in the hydrophobic segment is substituted with an R2 group. The hydrophobic segment may be characterized in particular by the substitution ratio for substitution with an R2 group. The substitution ratio “SR” for substitution with an R2 group is calculated according to the following formula (A): SR=n/x.
The substitution ratio SR for substitution of the hydrophobic segment with an R2 group is of at least 0.1 and of less than 1.0 generally, for example from 0.4 to less than 1.0, which includes from 0.7 to less than 1.0.
It should be noted that the substitution ratio SR for substitution with an R2 group is determined as an average value measured for a set of molecules of the corresponding block copolymer of formula (I). Thus, when the ratio SR is illustrated as 0.9, the actual measurement ratio may be between 0.79 and 0.98 due to the numerical allowance of the value “x”.
In general, the block copolymers defined in the present description can be synthesized according to the methods disclosed in European patent application No. EP2042184.
The block copolymers defined in the present description spontaneously form micelles when they are present in an aqueous solution, by self-association. It is specified that the specific structure of said block copolymers confers on them the property of self-association, i.e., in particular, their ability to spontaneously form stable nanoparticles of micelle type, having a hydrophobic core and a hydrophilic crown.
Without wishing to be bound by any particular theory, the applicant believes that the FVII/VIIa which is encapsulated in the micelles of said block copolymer defined above is subsequently released into the bloodstream in two distinct ways, respectively (i) by diffusion of the FVII/VIIa molecules through the micelle and (ii) by release of the FVII/VIIa molecules when the micelles dissociate after a certain residence time in the bloodstream.
The terms “factor VII”, “FVII” and “FVIIa” can be used without distinction to denote blood coagulation factor VII, as appropriate in its activated form (FVIIa), and encompass the mutants and the variants with respect to the FVII/VIIa naturally encoded in the genome of a mammal. As used herein, Factor VII encompasses FVII as well as FVIIa. The FVII/VIIa which is encapsulated in micelles in accordance with the invention is preferentially human FVII/VIIa, or a mutant or a variant of a human FVII/VIIa.
In order to prepare a pharmaceutical composition of the invention, use may be made of an FVII/VIIa purified from blood plasma or else of a recombinant FVII/VIIa, these two forms of FVII/VIIa being well known to those skilled in the art and readily commercially available.
An FVII/VIIa purified from blood plasma may, for example, be the pharmaceutical specialty marketed under the name “factor VII LFB” (French marketing authorization No. 5615752).
A recombinant human FVII/VIIa may, for example, consist of the pharmaceutical specialty marketed under the name NovoSeven® (NovoNordisk®, French marketing authorization No. 5730938 based on the European marketing authorization initially granted on 27 Jan. 2004). In this pharmaceutical specialty, the FVII/VIIa is in a lyophilized form.
A recombinant human FVII/VIIa may also consist of an FVII/VIIa produced in rabbits which are transgenic for the gene encoding human FVII, which can be produced in accordance with the teaching of PCT application No. WO2007/138199.
A recombinant FVII/VIIa may also consist of an FVII/VIIa produced in accordance with the teachings of the PCT application No. WO 2008/015339 or with the teachings of United States patent application No. US 2004185535.
As already previously specified, it also possible to use a factor VII consisting of a variant or a mutant of FVII/VIIa, in particular a variant or a mutant of human FVII/VIIa. As variants or mutants of human FVII/VIIa, use may, for example, be made of those which are described in the following documents: (i) PCT applications WO 2008127702, WO 2008155509, WO 0222776, WO 2009126307, WO 02077218, WO 03093465 and WO 0183725, and (ii) U.S. Pat. No. 7,416,860 and U.S. Pat. No. 7,419,803.
It is known in the prior art that, according to the type of FVII/VIIa under consideration, the activity of the FVII/VIIa can range from 500 to 4000 international units (IU) per milligram of FVII/VIIa protein. Illustratively, the type of FVII/FVIIa used in the examples has an activity of about 20001 U/mg FVII/FVIIa.
The examples illustrate the use of a recombinant human FVII/VIIa which has a specific activity of 2000 international units per milligram.
Advantageously, the micelles of block copolymer in which the FVII/VIIa is incorporated or encapsulated have an FVII/VIIa:copolymer mass ratio ranging from 1:100 wt:wt to 50:100 wt:wt, better still from 5:100 wt:wt to 20:100 wt:wt.
In general, those skilled in the art understand that the FVII/VIIa:copolymer mass ratio should have a value which is sufficiently large to allow the administration to the patient of a pharmaceutical composition comprising an amount of FVII/VIIa active ingredient that is compatible with the prophylactic or therapeutic efficacy that is desired.
Those skilled in the art also understand that the micelles of the block copolymer defined in the present description have the ability to incorporate a given amount of FVII/VIIa, with a maximum value for the FVII/VIIa:copolymer mass ratio above which the excess FVII/VIIa molecules are no longer satisfactorily incorporated into the micelles and would therefore be capable of being in free form in a pharmaceutical composition of the invention. Under conditions of a large excess mass of FVII/VIIa relative to said block copolymer, in which a part of the FVII/VIIa molecules are in free form, a modification of the pharmacokinetic profile of the corresponding FVII composition is induced, which may not comply with the objectives pursued by the present invention.
The examples illustrate pharmaceutical compositions of the invention in which the FVII/VIIa:copolymer mass ratio is 5:100 wt:wt and 10:100 wt:wt.
The pharmaceutical compositions of the invention comprising FVII/VIIa incorporated or encapsulated in micelles can be in liquid form or in lyophilized form.
The pharmaceutical compositions according to the invention may be prepared in lyophilized form. A suitable amount of sterile demineralized water is added to these lyophilized compositions in order to prepare a pharmaceutical composition of the invention in liquid form.
Those skilled in the art understand that, irrespective of the form in which a pharmaceutical composition of the invention is stored before use, mainly in solid form or in liquid form, said pharmaceutical composition is administered to the patient in liquid form.
Preferably, a pharmaceutical composition also comprises a buffer, or a combination of buffers, intended to adjust the pH value so as to stabilize the micelles in which the FVII/VIIa molecules are incorporated or encapsulated, most particularly when the pharmaceutical composition is in a liquid form.
The maintaining of the pH value of the pharmaceutical composition of the invention is in particular intended to promote the association of the FVII/VIIa molecules with the molecules of said block copolymer, within the micelles.
In some embodiments of a pharmaceutical composition of the invention, use is made of a buffer, or a combination of buffers, capable of maintaining the pH of said composition at a given pH value, in a range of pH values of from 4.5 to 6.5.
In some preferred embodiments, a buffer, or a combination of buffers, capable of maintaining the pH of said composition at a given pH value, in a range of pH values of from 5 to 6, is added.
Without wishing to be bound by any particular theory, the applicant believes that, at a given pH in the range of from pH 5 to pH 6, the interactions between the FVII/VIIa molecules and the molecules of block copolymer defined in the present description are promoted. It is specified that FVII/VIIa, and in particular a recombinant human FVII/VIIa, has an isoelectric point of between 6 and 7. In the embodiments of the pharmaceutical composition of the invention, in which the pH is maintained in a range of from pH 5 to pH 6, the molecules are in a charged form, just like the constitutive amino acid residues of the hydrophobic segment of the block copolymer, including the constitutive glutamate residues of the block copolymer of formula (I). The electrostatic interactions between the FVII/VIIa molecules and the molecules of said block copolymer are, in this pH range of from 5 to 6, overall attractive.
The examples illustrate embodiments of a pharmaceutical composition of the invention comprising a buffer capable of maintaining the pH of said composition in liquid form at a pH of 5, or else at a pH of 6.
Any type of physiologically acceptable buffer known to those skilled in the art can be used. A buffer may be present in a pharmaceutical composition of the invention in a final concentration range of from approximately 2 mM to 50 mM.
Use may in particular be made of a buffer, or a combination of buffers, chosen from organic acids or organic acids or salts thereof, such as:
The examples illustrate pharmaceutical compositions of the invention comprising a disambiguation (2-(N-morpholino) ethanesulfonic acid or MES) buffer. The MES buffer can be used at a final concentration of 10 mM.
Furthermore, a pharmaceutical composition of the invention comprising FVII/VIIa encapsulated in micelles formed from the block copolymer defined in the present description may also comprise a cryoprotective agent or a combination of cryoprotective agents.
The cryoprotective agent may be any type of cryoprotective agent well known to those skilled in the art. Use may in particular be made of a cryoprotective agent of the sugar type, for example a monosaccharide, a disaccharide or a polysaccharide. Use may, for example, be made of a cryoprotective agent chosen from DMSO, ethylene glycol, glycerol, sucrose or trehalose.
The examples illustrate pharmaceutical compositions of the invention in which the cryoprotective agent is sucrose.
A pharmaceutical composition according to the invention may comprise one or more physiologically acceptable additional excipients among those which are recommended by the European pharmacopeia or the US pharmacopeia in force. A pharmaceutical composition of the invention may comprise one or more additional excipients recommended in the 6th edition of the European Pharmacopeia of June 2007 or of the US Pharmacopeia of 2010.
When a pharmaceutical composition of the invention is in liquid form, in particular when it is in the form of a ready-to-use liquid, said pharmaceutical composition comprises a final concentration of said block copolymer defined in the present description in the form of micelles ranging from 1 mg/ml to 100 mg/ml.
Without wishing to be bound by any particular theory, the applicant believes that, at a lower final concentration of said block copolymer, the integrity of the micelles may be modified owing to the fact that the critical minimum concentration (CMC) for maintaining the arrangement of the molecules of said block copolymer in the micelle form is not reached.
At a concentration of said block polymer of greater than 100 mg/ml, the applicant believes that the viscosity characteristics of said pharmaceutical composition would lead to a reduced compliance of the said composition with its administration to the patient by injection.
In some preferred embodiments, a pharmaceutical composition in accordance with the invention, when it is in liquid form, in particular when it is in a ready-to-use liquid form, has a final concentration of said block copolymer, for example of the block copolymer of formula (I), ranging from 1 mg/ml to 50 mg/ml, including ranging from 5 mg/ml to 30 mg/ml.
In general, a pharmaceutical composition of the invention comprises an amount of FVII/VIIa suitable for obtaining activity of FVII/VIIa in a range of from 500 IU to 10 000 IU per dosage unit.
By way of illustration, for an FVII/VIIa having a specific activity of 2000 IU/mg, a dosage unit of the pharmaceutical composition of the invention at 5000 IU comprises 2.5 mg of FVII/FVIIa incorporated or encapsulated in micelles. Furthermore, for a pharmaceutical composition of the invention in which the FVII/VIIa:copolymer mass ratio is 10:100, said dosage unit comprises an amount of said copolymer in the form of micelles, for example of the copolymer of formula (I), which is 25 mg of said copolymer. Finally, in one embodiment of the pharmaceutical composition in which the final concentration of said copolymer is 25 mg/ml, said dosage unit, when it is in a ready-to-use liquid form, has a volume of 1 ml.
In some embodiments of a pharmaceutical composition according to the invention wherein the said composition consists of a liquid solution, the said composition comprises from 0.1 mg/ml to 10 mg/ml of FVII/FVIIa. In some of these embodiments, the said composition comprises from 0.5 mg/ml to 5 mg/ml of FVII/FVIIa. These embodiments encompass pharmaceutical compositions comprising about 1 mg/ml FVII/FVIIa.
It is understood that, in some presentation forms of a pharmaceutical composition of the invention, said composition in liquid form can be packaged in a bottle containing a volume sufficient for a plurality of dosage units, which are removed in order to successively fill the reservoir of the syringes which are subsequently used for the administration of said composition, by parenteral injection.
Generally, a pharmaceutical composition of the invention is suitable for parenteral administration thereof, which encompasses subcutaneous, intradermal and intravenous administration. Intravenous administration is preferred.
A pharmaceutical composition of the invention is generally intended for the prevention or treatment of coagulation disorders. A pharmaceutical composition according to the invention is used in any of the known medical indications and in any of the medical indications that will subsequently be identified for FVII/VIIa in general.
A pharmaceutical composition of the invention may, for example, be used for the treatment of haemorrhagic events related to an isolated constitutional deficiency in factor VII.
A pharmaceutical composition of the invention may also be used for the prevention of haemorrhagic events in the case of an isolated constitutional deficiency in factor VII and associated with a history in the patient.
A pharmaceutical composition according to the invention is in particular indicated in the treatment of haemorrhagic episodes and in the prevention of haemorrhage occurring during the surgical procedures or invasive procedures for the following groups of patients:
A pharmaceutical composition according to the invention is in particular indicated in the treatment of haemorrhagic episodes and in the prevention of haemorrhage occurring during surgical procedures or invasive procedures for the following groups of patients:
According to yet another aspect, the present invention relates to a pharmaceutical composition comprising factor VII encapsulated in micelles formed from a block copolymer molecules containing a hydrophilic polymer segment and a hydrophobic polymer segment consisting of a polyamino acid, which composition, when it is administered parenterally, is suitable for generating a pharmacokinetic profile having one or more of the following characteristics:
As mentioned above, the values of the MRT and CL should be obtained from seven-week-old rats of the Wistar strain.
Embodiments of a pharmaceutical composition above are described in detail throughout the whole present description.
The invention also relates to a factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and of (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group, for use thereof as a medicament.
The invention also relates to a factor VII encapsulated in micelles formed from block copolymer molecules containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group, for the treatment of coagulation disorders.
The invention also relates to the use of a factor VII encapsulated in micelles formed from a block copolymer molecule containing (i) a hydrophilic polymer segment consisting of a polyalkylene glycol and (ii) a hydrophobic polymer segment consisting of a polyamino acid, with said polyamino acid comprising exclusively amino acid residues selected from the group consisting of histidine, lysine, aspartic acid and glutamic acid residues, wherein a part of said amino acid residues is substituted with a hydrophobic group, for producing a medicament for the treatment of coagulation disorders.
By way of illustration, a pharmaceutical composition of the invention may be used for the treatment of haemorrhagic events, for example:
By way of illustration, a pharmaceutical composition of the invention may be used for treatment in the context of a surgical procedure: in order to obtain a circulating factor VII level of greater than 50% at the time of the surgical procedure, an amount of pharmaceutical composition according to the invention necessary for a loading dose of from 30 to 40 IU/kg of FVII/VIIa is injected one hour before the surgical act and the factor VII level is tested immediately before the procedure. The subsequent doses of the pharmaceutical composition of the invention will be administered every 6 to 8 hours, so as to maintain over the next few days:
The duration of the factor VII level correction and the biological monitoring are suitable for the clinical situation and the risk of haemorrhage.
By way of illustration, a pharmaceutical composition of the invention may be used for a prophylactic treatment: the pharmaceutical composition according to the invention may be indicated in the prevention of repeated haemorrhagic events, for example haemarthrosis, in individuals with a factor VII deficiency of <5%. The useful dose of the pharmaceutical composition of the invention is that necessary for a dosage of from 20 to 30 IU/kg of FVII/VIIa and should be injected at least two to three times a week for several weeks to several months. It should be modulated according to the results regarding the prevention of bleeding.
The present invention is also illustrated in a nonlimiting manner by the following examples:
Use was made of two types of self-associating copolymers of formula (I) of which the R2 group is (i) either an unsubstituted octyl chain, denoted “PEG-pGlu(OC8)-Ac”, (ii) or a benzyl group, denoted “PEG-pGlu(OBn)-Ac”.
The PEG-pGlu(OC8)-Ac copolymer has the following formula (I-A):
in which: the R1 group is a polyethylene glycol chain having a molecular mass of 10 kDa, and the poly(glutamate) chain of which comprises 40 glutamate units (x=40) wherein the substitution ratio for substitution of the glutamate residues with the octyl group is 0.9 (36 glutamate units are substituted out of the 40 constituent glutamate units of the poly(glutamate) chain).
The PEG-pGlu(OBn)-Ac copolymer has the following formula (I-B):
in which: the R1 group is a polyethylene glycol chain having a molecular mass of 10 kDa, of which the poly(glutamate) chain comprises 40 glutamate units (x=40) wherein the substitution ratio for substitution of the glutamate residues with the benzyl group is 0.9 (36 glutamate units are substituted out of the 40 constituent glutamate units of the poly(glutamate) chain).
Use was made of recombinant human factor VII/VIIa produced in rabbits' milk in accordance with the teaching of PCT application No. WO 2007/138199 in the name of the Laboratoire Francais du Fractionnement et des Biotechnologies.
The purified recombinant human FVII/VIIa has a specific activity of 2000 IU/mg.
The following are added to a final volume of 2.4 ml of an aqueous solution containing a 10 mM MES buffer at pH 5 and 10% sucrose: (i) 0.36 mg of the recombinant human FVII/VIIa and (ii) 3.6 mg of the PEG-pGlu(OC8)-Ac, at 4° C.
In the mixture, the FVII/VIIa and the PEG-pGlu(OC8)-Ac are in a mass ratio of 10:100.
After a period of incubation of the above mixture of 24 hours at 4° C., the PEG-pGlu(OC8)-Ac molecules, which are self-associating, formed micelles encapsulating the recombinant human FVII/VIIa.
The following are added to a final volume of 2.4 ml of an aqueous solution containing a 10 mM MES buffer at pH5: (i) 0.36 mg of the recombinant human FVII/VIIa and (ii) 3.6 mg of the PEG-pGlu(OBn)-Ac, at 4° C.
In the mixture, the FVII/VIIa and the PEG-pGlu(OBn)-Ac are in a mass ratio of 10:100.
After a period of incubation of the above mixture of 24 hours at 4° C., the PEG-pGlu(OBn)-Ac molecules, which are self-associating, formed micelles encapsulating the recombinant human FVII/VIIa.
Seven-week-old rats of the Wistar strain were used.
Groups of three rats were used, the rats of the same group receiving the same treatment.
A micelle-free FVII/VIIa solution was administered i.v. at a dose of 600 IU/kg to a first group of three rats.
A solution of FVII/VIIa encapsulated in micelles of PEG-pGlu(OC8)-Ac was administered i.v. at a dose of 600 IU/kg to a second group of three rats.
A solution of FVII/VIIa encapsulated in the micelles of PEG-pGlu(OBn)-Ac was administered i.v. in the tail, at a dose of 600 IU/kg, to a third group of three rats.
The pharmacokinetic profiles for each of the three formulations were produced with the FVII ELISA detection kit sold by the company Diagnostica Stago under the name “Asserachrom® VII:Ag”, using the following protocol:
The plasma FVII/VIIa concentration was measured for each of the rats at the following times after injection: 5 minutes, 0.5 hour, 1 hour, 2 hours, 8 hours, 24 hours and 48 hours.
The results are illustrated in
The results in
The protocol described in example 1 was used to prepare the following five formulations:
The pharmacokinetic assays were carried out under the same conditions as in example 1.
The results are illustrated in
The results in
The results in
The various characteristic values of the pharmacokinetic profiles of some of the formulations tested are reported in table 1 below:
The results in Table I illustrate the best pharmacokinetic profile parameters obtained with the various embodiments of a pharmaceutical composition comprising recombinant human FVII/VIIa encapsulated in micelles formed from a copolymer of formula (I).
The value of the AUC of the compositions of FVII/VIIa encapsulated in micelles of a copolymer of formula (I) may in particular be noted, said value being, respectively, 2.3 times greater (PEG-pGlu(OBn)-Ac) and 2.9 times greater (PEG-pGlu(OC8)-Ac) than the AUC measured for the corresponding formulation of FVII/VIIa which is free of micelles.
In addition, the results in table I show that the MRT residence time value for the FVII/VIIa in the bloodstream is, respectively, 3.7 times greater (PEG-pGlu(OBn)-Ac) and 11.9 times greater (PEG-pGlu(OC8)-Ac) than the MRT value measured for the corresponding formulation of FVII/VIIa which is free of micelles.
Finally, the results in table 1 show that the pharmacokinetic profile obtained with the PEG-pGlu(OC8)-Ac-based formulation is more advantageous than the pharmacokinetic profile obtained with the PEG-pGlu(OBn)-Ac-based formulation.
The protocol described in example 1 was used to prepare the following three formulations:
The pharmacokinetic assays were carried out under the same conditions as in example 1.
The results are illustrated in
The results in
The characteristic values of the pharmacokinetic profiles of the three formulations tested are reported in table II below:
The results in table II illustrate the better pharmacokinetic profile parameters obtained with the various embodiments of a pharmaceutical composition comprising recombinant human FVII/VIIa encapsulated in micelles formed from a copolymer of formula (I).
The value of the AUC of the compositions of FVII/VIIa encapsulated in micelles of a copolymer of formula (I) may in particular be noted, said value being, respectively, 3.2 times greater (PEG-pGlu(OBn)-Ac) and 4.0 times greater (PEG-pGlu(OC8)-Ac) than the AUC measured for the corresponding formulation of FVII/VIIa which is free of micelles.
In addition, the results in table II show that the MRT residence time value for the FVII/VIIa in the bloodstream is, respectively, 3.0 times greater (PEG-pGlu(OBn)-Ac) and 8 times greater (PEG-pGlu(OC8)-Ac) than the MRT value measured for the corresponding formulation of FVII/VIIa which is free of micelles.
Finally, the results in table II show that the pharmacokinetic profile obtained with the PEG-pGlu(OC8)-Ac-based formulation is more advantageous than the pharmacokinetic profile obtained with the PEG-pGlu(OBn)-Ac-based formulation.
Furthermore,
The results in
The results in
For all the formulations comprising micelles that were tested, a considerable increase in the mean residence time (MRT) of the FVII/VIIa in the bloodstream was measured.
The results in
A. Method for Preparing the Comparative Formulations
The protocol described in example 1 was used to prepare the following four formulations:
Purified human FIX sold by LFB under the name Betafact was used for producing the formulations.
The pharmacokinetic assays were carried out under the same conditions as in example 1, using FIX at a dose of 200 IU/kg, using the FIX ELISA detection kit sold by the company Diagnostica Stago under the name “Asserachrom® IX:Ag”
The results are illustrated in
The results in
Thus, the results in
These results show that the technical solution which was developed according to the invention for preparing improved pharmaceutical compositions of FVII/VIIa is not at all transposable to the preparation of improved compositions of another coagulation factor, which nevertheless has many structural and functional characteristics in common with FVII/VIIa.
The objectives of Example 5 was to test the preservation of factor VII activity in a pharmaceutical composition comprising factor VII encapsulated in micelles of a block-copolymer of formula (I) described in the present specification.
In this example, the said pharmaceutical composition is also termed FVIIa-SR (for FVIIa sustained release).
The test was performed by including a comparative pharmaceutical composition comprising a non-encapsulated FVII factor. In this example, the said comparative pharmaceutical composition is also termed FVIIa-IR (for FVIIa Immediate Release).
The source of FVIIa was a recombinant human FVIIa purified from the milk of rabbits transgenic for human FVII in accordance with the teaching of PCT application No. WO 2007/138199 in the name of Laboratoire Francais du Fractionnement et des Biotechnologies.
In the FVIIa-SR pharmaceutical composition, FVIIa was encapsulated in micelles of pGlu(OC8)-Ac with a protein/polymer mass ratio of 10:100 in an aqueous solution containing sodium at citrate 1.5 g/L and 10% sucrose. The pH was adjusted to 5.2. The FVIIa concentration was 0.4 g/L to 1.1 g/L.
FVIIa titration is performed with the FVII ELISA kit Asserachrom® VII: Ag from Diagnostica Stago, according to the instructions of use of the manufacturer.
FVIIa titration by the chronometric method performed on the BCS XP machine (Siemens) consists in a measurement of the clotting time in presence of recombinant soluble tissue factor, phospholipids and calcium, in a solution where all the factors are in excess except for FVIIa, FVIIa being brought by the dilution of the sample. The FVIIa titration was performed according to the instruction of use of the manufacturer.
Both for the ELISA and for the FVII clotting time test, samples are pre-treated for 1 hour at 4° C. with a surfactant solution (NP-40 at a final concentration of 0.1%) to dissolve the micelles and release all the FVIIa previously entrapped into the micelles.
The results are presented in the Table III below.
The results presented in Table III above show that the FVIIa activity is not altered when FVIIa is encapsulated in the micelles of block copolymer described in this patent application.
The objectives of Example 6 was to test the in vivo efficacy of a pharmaceutical composition comprising factor VII encapsulated in micelles of a block-copolymer of formula (I) described in the present specification.
In this example, the said pharmaceutical composition is also termed FVIIa-SR (for FVIIa sustained release).
The test was performed by including a comparative pharmaceutical composition comprising a non-encapsulated FVII factor. In this example, the said comparative pharmaceutical composition is also termed FVIIa-IR (for FVIIa Immediate Release).
A tail-clip model was used as efficacy test. In this model, the tail extremity of factor VIII deficient mice or Hemophilia A mice is amputated. These mice have less than 1% of normal factor VIII activity and have increased blood loss in the tail-clip model compared to wild-type mice of the same strain.
The amount of blood loss was measured to compare the homeostatic effect of FVIIa-SR and FVIIa-IR. Two doses of FVIIa-SR and FVIIa-IR (4 mg/kg and 8 mg/kg) were administered and two time points after injection (5 minutes and 120 minutes) were selected to measure blood loss. FVIIa-SR and FVIIa-IR efficacies were evaluated using negative and positive controls, i.e. saline (NaCl 0.9%) and factor VIII-injected hemophilia A mice, respectively.
The source of FVIIa was a recombinant human FVIIa purified from the milk of rabbits transgenic for human FVII in accordance with the teaching of PCT application N° WO 2007/138199 in the name of Laboratoire Francais du Fractionnement et des Biotechnologies.
In the FVIIa-SR pharmaceutical composition, FVIIa was encapsulated in micelles of pGlu(OC8)-Ac with a protein/polymer mass ratio of 10:100 in an aqueous solution containing sodium at citrate 1.5 g/L and 10% sucrose. The pH was adjusted to 5.2. The FVIIa concentration was 0.4 g/L to 1.1 g/L
Batch samples of FVIIa-SR were prepared at a final protein concentration of 0.4 g/L.
Batch samples of FVIIa-IR were prepared at a final protein concentration of 0.4 g/L.
All batch samples were stored at −70° C. until use. For the test, samples were thawed at room temperature and injected to animals within three hours.
Commercial human plasma-derived factor VIII Factane® (FAC, LFB, Les Ulis, France) at 1000 IU/mL was used as factor VIII. Each vial was kept at 4° C. until use. FVIII was resuspended to 50 IU/mL with 20 mL distilled water, then diluted to 10 IU/mL in PBS (PAA laboratories, Les Mureaux, France) and injected to animals within three hours.
Sodium chloride solution at 0.9% was used as negative control product in hemophilia A. This product was stored at room temperature.
A factor VIII deficient mice colony was used. 85 mice of 8 to 12 weeks old were used. Breeding pairs of exon 16 factor VIII-deficient mice or hemophilia A mice were purchased from The Jackson laboratory (Bar Harbor, Me., USA). These animals were backcrossed to C57BL/6 WT mice (Janvier, Le Genest-St-Isle, France) for 8 generations. Control C57BL/6 WT mice have been derived from the last backcrosses of hemophilia A mice to ensure similar genetic background. Mice were housed as recommended by French regulations and the experimental guidelines of the European Union. Temperature, hygrometry, ventilation were controlled and recorded. A dried standard rodent diet as well as a fresh water were offered ad libitum.
A total of 85 hemophilia A mice were used in this study. At the time of the experiment, mice were weighed for anaesthetics and products dosage. Tails were immersed in a water-bath at 37° C. 3 minutes before product administration. Then, mice were placed in a mouse restrainer to adequately restrain the animal while having access to its tail vein for products administration. Immediately after product administration, mice were anesthetized by intraperitoneal injection of tribromoethanol at a dosage of 0.02 mL/g body weight of a 1.25% solution. During the experiment the temperature of the animal was kept constant to 37° C.
The tested products were injected as disclosed in Table IV hereunder. Briefly, two doses of FVIIa-IR or FVIIa-SR were administered to hemophilia A mice. The first dose was of 4 mg/kg for each product injected to 10 mice. As control, FVIII at a dose of FVIII:C of 100 IU/kg was injected to 11 hemophilia A mice. Furthermore, 19 hemophilia A mice were injected with NaCl 0.9%. For all products, the volume injected was of 200 to 250 μl depending of the dose and the concentration of the product injected. Based on the results obtained for this dose of FVIIa(SR (4 mg/kg), another dose of 8 mg/kg was tested. The same number of animals (10) was included for this new dose. The effect of these doses was evaluated in the tail-clip model 5 minutes after product administration (See details in Table IV below). Then, 15 and 18 hemophilia A mice were injected with 8 mg/kg of FVIIa-IR and FVIIa-SR, respectively. The effect of these doses was evaluated in the tail-clip model 120 minutes after product administration.
Mouse tail-bleeding time was performed using the tail-clip assay under tribromoethanol anesthesia. A scalpel was used to cut 3 mm of the tail-tip of anesthesized mice. In a first group of animals, to determine the optimal dose of FVIIa-SR efficiency, the transection of the tail was 5 minutes after the product administration. Then, in a second group of animals, the transaction was made at a time point when FVIIa-IR efficiency cannot be detected (2 hours) while hopefully FVIIa-SR still could be efficient to correct bleeding loss of hemophilia A mice.
The amputated tail was immersed immediately after transaction in a 50 ml tube full of warm physiological saline. Blood was collected for 30 min at 37° C. After 30 min, the mixture of blood and physiological saline was centrifuged at 1500 g. The red blood cells pellet was then be lysed in H2O and the amount of haemoglobin was obtained by reading the absorbance at 416 nm. The volume of blood lost in each sample was calculated from a standard curve, which was obtained by lysing defined volume (20 μl, 40 μl, 60 μL, 80 μl and 100 μl) of mouse blood in H2O to extract haemoglobin as described above. At the end of the experiment all animals were anesthetized and euthanized by cervical dislocation.
The Mann-Whitney U-test determined statistical differences in blood loss between two groups using the KaleidaGraph® software (version 1.0, Synergy Software, Reading, Pa., USA). Stastistical significance was accepted when P<=0.05.
To validate the tail-clip model in hemophilia A mice, FVIII was tested at 100 IU/kg. Blood loss was measured 5 min after FVIII or NaCl 0.9% administration. Results are presented in Table V and
Administration of FVIII at 100 IU/kg induced a significant decrease in blood loss (P=0.0001, Mann-Whitney U-test) compared with the negative control group (NaCl 0.9%).
Two doses of FVIIa-SR (4 and 8 mg/kg) were administered to hemophilia A mice. Results are presented in Table VI and
To evaluate and compare the ability of both FVIIa-SR and FVIIa-IR to induce a significant decrease in blood loss 120 min after administration, both molecules were administered at 8 mg/kg to hemophilia A mice. Results are presented in Table VII and
FVIIa-SR showed a significant ability to correct blood loss in an in vivo tail-clip model in hemophilia A mice. 120 minutes, as well as 5 minutes, after its administration at 8 mg/kg, this product can significantly reduce blood loss whereas in the same conditions FVIIa-IR cannot.
| Number | Date | Country | Kind |
|---|---|---|---|
| 11176276.1 | Aug 2011 | EP | regional |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IB2012/053914 | 7/31/2012 | WO | 00 | 4/17/2014 |
