Patent Description:
Pre-filled syringes that are obtained by filling syringes with injection liquids in advance have been increasingly used in recent years because such pre-filled syringes are extremely convenient to use and can prevent medical accidents such as the mistaken use of an injection liquid.

The injection liquid with which a pre-filled syringe is filled may, for example, be a formulation that contains a protein in an aqueous solution (protein solution formulation). A problem faced by pre-filled syringes that are filled with protein solution formulations such as described above is that protein aggregation may occur during long-term storage.

In response to this problem, Patent Literature (PTL) <NUM>, for example, proposes a technique in which the protein concentration in a protein solution formulation that contains erythropoietin as a protein is set within a specific range, in which a non-ionic surfactant and a tonicity agent are included in the formulation, and in which a vessel having a hydrophobic resin selected from <NUM>) a cycloolefin copolymer that is a copolymer of a cycloolefin and an olefin, <NUM>) a cycloolefin ring-opened polymer, and <NUM>) a product obtained through hydrogenation of a cycloolefin ring-opened polymer as the material of a part that is in direct contact with the formulation is used as a vessel that is filled with the formulation. Polysorbate <NUM> and polysorbate <NUM>, for example, are used as the non-ionic surfactant in PTL <NUM>. The non-ionic surfactant can function as a stabilizer for erythropoietin (i.e., the protein). <CIT>, <CIT> and <CIT> also describe syringes prefilled with a protein formulation.

However, non-ionic surfactants such as polysorbate <NUM> and polysorbate <NUM> may decompose in a protein solution formulation during long-term storage of a pre-filled syringe, leading to production of decomposition products. Such decomposition products have drawbacks in terms that they are carcinogenic and may lead to problems such as hypersensitivity and chromosome abnormalities upon administration to a human body.

In other words, the conventional pre-filled syringe described above leaves room for further improvement in terms of inhibiting protein aggregation in a protein solution formulation while also suppressing production of a decomposition product of a non-ionic surfactant during long-term storage.

Accordingly, one object of the present disclosure is to provide a pre-filled syringe that can inhibit protein aggregation in a protein solution formulation after long-term storage while also reducing the produced amount of a decomposition product of a non-ionic surfactant after long-term storage.

Another object of the present disclosure is to provide a method of producing a pre-filled syringe that can inhibit protein aggregation in a protein solution formulation after long-term storage while also reducing the produced amount of a decomposition product of a non-ionic surfactant after long-term storage.

The inventor conducted diligent studies with the aim of solving the problems set forth above. The inventor discovered that by filling a syringe including a barrel formed using a specific resin with a protein solution formulation having a non-ionic surfactant concentration within a specific range to produce a pre-filled syringe, it is possible to inhibit protein aggregation in the protein solution formulation and to reduce the produced amount of a decomposition product of the non-ionic surfactant even in a situation in which the pre-filled syringe is stored for a long time. In this manner, the inventor completed the present disclosure.

Specifically, the present disclosure aims to advantageously solve the problems set forth above, by providing a prefilled syringe according to claim <NUM> and a method for producing said syringe according to claim <NUM>. Further aspects of the invention are described in the dependent claims. The pre-filled syringe comprises: a barrel including a nozzle at a tip thereof; a sealing member sealing the nozzle; a gasket slidably housed inside the barrel; a plunger linked to the gasket and performing a movement operation of the gasket in a longitudinal direction of the barrel; and a protein solution formulation filled into a space defined by the sealing member, the gasket, and a region that is part of an inner wall surface of the barrel, wherein the barrel is formed of a resin containing either or both of a hydrogenated cycloolefin ring-opened polymer and a copolymer of a cycloolefin and a chain olefin, and the protein solution formulation has a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL. In a pre-filled syringe in which a syringe including a barrel formed from a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin is filled with a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL in this manner, protein aggregation in the protein solution formulation is inhibited and the produced amount of a decomposition product of the non-ionic surfactant is low even in a situation in which the pre-filled syringe is stored for a long time.

In the presently disclosed pre-filled syringe, the region that is part of the inner wall surface has a water contact angle of <NUM>° or more. A pre-filled syringe that includes a barrel in which a region that is part of an inner wall surface that is in contact with a protein solution formulation (hereinafter, also referred to as a "formulation contacting region") has a water contact angle of <NUM>° or more can further inhibit protein aggregation in the protein solution formulation in a situation in which the pre-filled syringe is stored for a long time.

Note that the "water contact angle" of a formulation contacting region referred to in the present disclosure can be measured by a method described in the EXAMPLES section of the present specification.

In the presently disclosed pre-filled syringe, the protein solution formulation can contain either or both of an antibody and an antigen binding fragment of the antibody.

Moreover, in the presently disclosed pre-filled syringe, the antibody can be at least one selected from the group consisting of chimeric antibodies, human antibodies, humanized antibodies, and domain antibodies of any thereof.

Furthermore, in the presently disclosed pre-filled syringe, the protein solution formulation can contain at least one selected from the group consisting of ofatumumab, cetuximab, tocilizumab, bevacizumab, canakinumab, golimumab, ustekinumab, eculizumab, omalizumab, trastuzumab, pertuzumab, adalimumab, denosumab, mogamulizumab, rituximab, ranibizumab, infliximab, aflibercept, abatacept, etanercept, gemtuzumab ozogamicin, panitumumab, basiliximab, certolizumab pegol, and palivizumab.

Moreover, the present disclosure aims to advantageously solve the problems set forth above, and a presently disclosed method of producing a pre-filled syringe is a method of producing a pre-filled syringe having a protein solution formulation filled into an inner part of a syringe that includes: a barrel including a nozzle at a tip thereof; a sealing member sealing the nozzle; a gasket slidably housed inside the barrel; and a plunger linked to the gasket and performing a movement operation of the gasket in a longitudinal direction of the barrel, the method of producing a pre-filled syringe comprising a step of loading a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL into a barrel that is formed of a resin containing either or both of a hydrogenated cycloolefin ring-opened polymer and a copolymer of a cycloolefin and a chain olefin to obtain a pre-filled syringe having the protein solution formulation filled into a space defined by the sealing member, the gasket, and a region that is part of an inner wall surface of the barrel. By filling a syringe that includes a barrel formed from a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin with a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL in this manner, protein aggregation in the protein solution formulation can be inhibited and the produced amount of a decomposition product of the non-ionic surfactant can be reduced in a situation in which the obtained pre-filled syringe is stored for a long time.

In the presently disclosed method of producing a pre-filled syringe, the region that is part of the inner wall surface has a water contact angle of <NUM>° or more. By using a barrel in which the water contact angle of a formulation contacting region is <NUM>° or more, protein aggregation in the protein solution formulation can be further inhibited in a situation in which the obtained pre-filled syringe is stored for a long time.

The presently disclosed method of producing a pre-filled syringe further comprises, in advance of the step of obtaining the pre-filled syringe: a step of pre-drying the resin; and a step of shaping the resin after the pre-drying to obtain the barrel. By using a barrel that is obtained through shaping of a resin that has been pre-dried, protein aggregation in the protein solution formulation can be further inhibited in a situation in which the obtained pre-filled syringe is stored for a long time.

In the presently disclosed method of producing a pre-filled syringe, the resin preferably has an oxygen concentration of <NUM> mass ppm or less after the pre-drying. When the oxygen concentration in the pre-dried resin is <NUM> mass ppm or less, protein aggregation in the protein solution formulation can be even further inhibited in a situation in which the obtained pre-filled syringe is stored for a long time.

Note that the "oxygen concentration" in a resin referred to in the present disclosure can be measured by a method described in the EXAMPLES section of the present specification.

In the presently disclosed method of producing a pre-filled syringe, the pre-drying is preferably performed in an inert gas atmosphere. By performing pre-drying of the resin in an inert gas atmosphere, protein aggregation in the protein solution formulation can be even further inhibited in a situation in which the obtained pre-filled syringe is stored for a long time.

In the presently disclosed method of producing a pre-filled syringe, the pre-drying preferably has a drying temperature of not lower than <NUM> and not higher than <NUM>. By performing pre-drying of the resin at a temperature within the range set forth above, protein aggregation in the protein solution formulation can be even further inhibited in a situation in which the obtained pre-filled syringe is stored for a long time.

In the presently disclosed method of producing a pre-filled syringe, the protein solution formulation can contain either or both of an antibody and an antigen binding fragment of the antibody.

Moreover, in the presently disclosed method of producing a pre-filled syringe, the antibody can be at least one selected from the group consisting of chimeric antibodies, human antibodies, humanized antibodies, and domain antibodies of any thereof.

Furthermore, in the presently disclosed method of producing a pre-filled syringe, the protein solution formulation can contain at least one selected from the group consisting of ofatumumab, cetuximab, tocilizumab, bevacizumab, canakinumab, golimumab, ustekinumab, eculizumab, omalizumab, trastuzumab, pertuzumab, adalimumab, denosumab, mogamulizumab, rituximab, ranibizumab, infliximab, aflibercept, abatacept, etanercept, gemtuzumab ozogamicin, panitumumab, basiliximab, certolizumab pegol, and palivizumab.

According to the present disclosure, it is possible to provide a pre-filled syringe that can inhibit protein aggregation in a protein solution formulation after long-term storage while also reducing the produced amount of a decomposition product of a non-ionic surfactant after long-term storage.

Moreover, according to the present disclosure, it is possible to provide a method of producing a pre-filled syringe that can inhibit protein aggregation in a protein solution formulation after long-term storage while also reducing the produced amount of a decomposition product of a non-ionic surfactant after long-term storage.

<FIG> illustrates schematic configuration of one example of a pre-filled syringe in accordance with the present disclosure.

The presently disclosed pre-filled syringe has a protein solution formulation filled into an inner part of a syringe. Moreover, the presently disclosed pre-filled syringe can be produced by the presently disclosed method of producing a pre-filled syringe, for example.

The presently disclosed pre-filled syringe includes: a barrel including a nozzle at a tip thereof; a sealing member sealing the nozzle; a gasket slidably housed in the barrel; and a plunger linked to the gasket and performing a movement operation of the gasket in a longitudinal direction of the barrel. A protein solution formulation is filled into a space defined by the sealing member, the gasket, and a formulation contacting region that is part of an inner wall surface of the barrel.

The following describes one example of the structure of the presently disclosed pre-filled syringe set forth above with reference to the drawing. A pre-filled syringe <NUM> illustrated in <FIG> includes a barrel <NUM>, a sealing member (cap in <FIG>) <NUM>, a gasket <NUM>, a plunger <NUM>, and a protein solution formulation <NUM>. The barrel <NUM> includes a nozzle <NUM> at a tip <NUM> thereof. The sealing member <NUM> is fitted to the nozzle <NUM>. The gasket <NUM> can slide inside the barrel <NUM> in a longitudinal direction of the barrel <NUM> and this sliding of the gasket <NUM> can be performed through the plunger <NUM> that is linked to the gasket <NUM>. The protein solution formulation <NUM> is filled into a space defined by the sealing member <NUM>, the gasket <NUM>, and a formulation contacting region <NUM> that is a region that is part of an inner wall surface <NUM> of the barrel <NUM>.

Features of the presently disclosed pre-filled syringe are that the protein solution formulation with which the pre-filled syringe is filled has a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL and that the barrel is obtained through shaping of a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin.

The presently disclosed pre-filled syringe can inhibit protein aggregation in the protein solution formulation even in a situation in which the pre-filled syringe is stored for a long time and can also limit the amount of a decomposition product of the non-ionic surfactant that is produced after long-term storage to a low level. It is presumed that such an effect is obtained for the following reason.

Specifically, the presently disclosed pre-filled syringe is filled with a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL. The non-ionic surfactant that is contained as an essential component of the protein solution formulation functions as a stabilizer for a protein. On the other hand, even in a situation in which decomposition of the non-ionic surfactant occurs, the amount of a decomposition product of the non-ionic surfactant that is produced can be limited to a low level as a result of the protein solution formulation having a low non-ionic surfactant concentration of less than <NUM>/mL.

In addition, in the presently disclosed pre-filled syringe, the protein solution formulation set forth above is filled into a barrel that is obtained through shaping of a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin. It is presumed that a barrel that is a shaped product of the specific resin set forth above has reduced affinity between a formulation contacting region thereof and a protein due to the hydrophobic nature of the resin set forth above, and thus adsorption of the protein to the formulation contacting region can be inhibited, and aggregation of the protein in the formulation contacting region (i.e., on an inner wall surface of the barrel) can be inhibited. The contribution of the resin described above is thought to act in combination with the contribution of the previously mentioned non-ionic surfactant as a stabilizer to thereby enable inhibition of protein aggregation in the protein solution formulation even in a situation in which the pre-filled syringe is stored for a long time.

The following describes the protein solution formulation with which the presently disclosed pre-filled syringe is filled and the syringe (barrel, sealing member, gasket, and plunger) that is a constituent of the presently disclosed pre-filled syringe with reference to <FIG>, as necessary.

The protein solution formulation contains at least a protein, a non-ionic surfactant, and water and has a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL.

The protein contained in the protein solution formulation is not specifically limited and may, for example, be an antibody (chimeric antibody, human antibody, humanized antibody, or domain antibody of any thereof) or an antigen binding fragment of the antibody.

More specific examples of the protein include ofatumumab (product name: Arzerra® (Arzerra is a registered trademark in Japan, other countries, or both)), cetuximab (product name: Erbitux® (Erbitux is a registered trademark in Japan, other countries, or both)), tocilizumab (product name: Actemra® (Actemra is a registered trademark in Japan, other countries, or both)), bevacizumab (product name: Avastin® (Avastin is a registered trademark in Japan, other countries, or both)), canakinumab (product name: Ilaris® (Ilaris is a registered trademark in Japan, other countries, or both)), golimumab (product name: Simponi® (Simponi is a registered trademark in Japan, other countries, or both)), ustekinumab (product name: Stelara® (Stelara is a registered trademark in Japan, other countries, or both)), eculizumab (product name: Soliris® (Soliris is a registered trademark in Japan, other countries, or both)), omalizumab (product name: Xolair® (Xolair is a registered trademark in Japan, other countries, or both)), trastuzumab (product name: Herceptin® (Herceptin is a registered trademark in Japan, other countries, or both)), pertuzumab (product name: Perjeta® (Perjeta is a registered trademark in Japan, other countries, or both)), adalimumab (product name: Humira® (Humira is a registered trademark in Japan, other countries, or both)), denosumab (product name: Prolia® (Prolia is a registered trademark in Japan, other countries, or both); product name: Ranmark® (Ranmark is a registered trademark in Japan, other countries, or both)), mogamulizumab (product name: Poteligeo® (Poteligeo is a registered trademark in Japan, other countries, or both)), rituximab (product name: Rituxan® (Rituxan is a registered trademark in Japan, other countries, or both)), ranibizumab (product name: Lucentis® (Lucentis is a registered trademark in Japan, other countries, or both)), infliximab (product name: Remicade® (Remicade is a registered trademark in Japan, other countries, or both)), aflibercept (product name: Eylea® (Eylea is a registered trademark in Japan, other countries, or both)), abatacept (product name: Orencia® (Orencia is a registered trademark in Japan, other countries, or both)), etanercept (product name: Enbrel® (Enbrel is a registered trademark in Japan, other countries, or both)), gemtuzumab ozogamicin (product name: Mylotarg® (Mylotarg is a registered trademark in Japan, other countries, or both)), panitumumab (product name: Vectibix® (Vectibix is a registered trademark in Japan, other countries, or both)), basiliximab (product name: Simulect® (Simulect is a registered trademark in Japan, other countries, or both)), certolizumab pegol (product name: Cimzia® (Cimzia is a registered trademark in Japan, other countries, or both)), and palivizumab (product name: Synagis® (Synagis is a registered trademark in Japan, other countries, or both)).

Note that the protein solution formulation may contain one type of protein or may contain two or more types of proteins. In other words, the protein solution formulation may contain both an antibody and an antigen binding fragment, may contain two or more types of antibodies, or may contain two or more types of antigen binding fragments, for example.

The concentration of the protein in the protein solution formulation is preferably <NUM>/mL or more, more preferably <NUM>/mL or more, and even more preferably <NUM>/mL or more, and is preferably <NUM>/mL or less, more preferably <NUM>/mL or less, and even more preferably <NUM>/mL or less. When the concentration of the protein in the protein solution formulation is <NUM>/mL or more, the expected effect of the protein can be sufficiently obtained when the protein solution formulation is administered to a human body or the like. Moreover, when the concentration of the protein in the protein solution formulation is <NUM>/mL or less, aggregation of the protein in the protein solution formulation can be further inhibited during long-term storage of the pre-filled syringe.

The non-ionic surfactant is a component that can function as a stabilizer for stabilizing the protein described above. Examples of such non-ionic surfactants include, but are not specifically limited to, sorbitan fatty acid esters, glycerin fatty acid esters, polyglycerin fatty acid esters, polyoxyethylene sorbitan fatty acid esters (polyoxyethylene sorbitan oleate (polysorbate <NUM>), polyoxyethylene sorbitan monolaurate (polysorbate <NUM>), etc.), polyoxyethylene sorbitol fatty acid esters, polyoxyethylene glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene hydrogenated castor oil, polyoxyethylene beeswax derivatives, polyoxyethylene lanolin derivatives, and polyoxyethylene fatty acid amides.

Note that one non-ionic surfactant may be used individually, or two or more non-ionic surfactants may be used in combination.

The concentration of the non-ionic surfactant in the protein solution formulation is required to be more than <NUM>/mL and less than <NUM>/mL, is preferably <NUM>/mL or more, and more preferably <NUM>/mL or more, and is preferably <NUM>/mL or less, and more preferably <NUM>/mL or less. When the non-ionic surfactant concentration in a protein solution formulation is <NUM>/mL (i.e., when the protein solution formulation does not contain a non-ionic surfactant), it is not possible to inhibit protein aggregation in the protein solution formulation during long-term storage of a pre-filled syringe. On the other hand, when the non-ionic surfactant concentration in a protein solution formulation is <NUM>/mL or more, the amount of a decomposition product of the non-ionic surfactant that is produced during long-term storage of a pre-filled syringe cannot be limited to a low level.

Note that in a case in which the non-ionic surfactant is a non-ionic surfactant that includes a polyoxyethylene chain (polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene hydrogenated castor oil, polyoxyethylene beeswax derivative, polyoxyethylene lanolin derivative, polyoxyethylene fatty acid amide, etc.), for example, the decomposition product referred to above may be a decomposition product that is produced through severing of the end of the polyoxyethylene chain due to self-oxidation thereof.

The protein solution formulation may contain components other than a protein, water, and a non-ionic surfactant (i.e., other components). Examples of other components that are optionally contained in the protein solution formulation include known components that can be used in production of protein solution formulations. Examples of such known components include stabilizers (excluding the non-ionic surfactants described above), diluents, solubilizers, tonicity agents, excipients, pH modifiers, numbing agents, buffering agents, sulfur-containing reducing agents, and antioxidants. Further examples of other components include inorganic salts such as sodium chloride, potassium chloride, calcium chloride, sodium phosphate, potassium phosphate, and sodium hydrogen carbonate; and organic salts such as sodium citrate, potassium citrate, and sodium acetate. Note that the inorganic salt concentration in the protein solution formulation is preferably <NUM> or less. Moreover, the organic salt concentration in the protein solution formulation is preferably <NUM> or less.

No specific limitations are placed on the method by which the protein solution formulation is produced so long as it is possible to obtain a protein solution formulation in which at least a protein is dissolved and in which the non-ionic surfactant concentration is within a specific range. For example, the protein solution formulation can be obtained by dissolving the protein and a surfactant that is used as necessary in an aqueous buffer solution such as an acetate buffer solution, a phosphate buffer solution, or a citrate buffer solution.

The pH of the obtained protein solution formulation is not specifically limited and can be not lower than <NUM> and not higher than <NUM>.

The barrel included in the presently disclosed pre-filled syringe is a member that includes a nozzle at a tip thereof and that can house the protein solution formulation and the gasket in an inner part thereof. In the pre-filled syringe <NUM> illustrated in <FIG>, for example, the barrel <NUM> includes a barrel main body <NUM>, a nozzle <NUM> disposed at a tip end (tip <NUM>) of the barrel main body <NUM>, and a flange <NUM> disposed at a base end of the barrel main body <NUM>.

The barrel main body <NUM> is a tube-shaped part that houses the gasket <NUM> in a liquid-tight and slidable manner.

The nozzle <NUM> is a tube-shaped part that has a smaller diameter than the barrel main body <NUM>. The nozzle <NUM> includes an opening at the tip thereof for expelling the protein solution formulation <NUM> inside the barrel <NUM>.

The barrel <NUM> is in contact with the protein solution formulation <NUM> in a formulation contacting region <NUM> that is part of an inner wall surface <NUM> in the barrel main body <NUM> and the nozzle <NUM>.

The barrel is a shaped product of a resin that contains either or both of a hydrogenated cycloolefin ring-opened polymer and a copolymer of a cycloolefin and a chain olefin. Note that the resin used to form the barrel may contain components other than the hydrogenated cycloolefin ring-opened polymer and the copolymer of a cycloolefin and a chain olefin mentioned above (i.e., other components).

The hydrogenated cycloolefin ring-opened polymer is a polymer that is obtained by performing ring-opening polymerization of a cycloolefin as a monomer to obtain a cycloolefin ring-opened polymer, and then further subjecting the obtained cycloolefin ring-opened polymer to a hydrogenation reaction.

A compound that has a cyclic structure formed of carbon atoms and includes a polymerizable carbon-carbon double bond in the cyclic structure can be used as a cycloolefin serving as a monomer in production of the cycloolefin ring-opened polymer. Specifically, the cycloolefin serving as a monomer may be a norbornene-based monomer (monomer including a norbornene ring) or a monocyclic cycloolefin monomer. Note that in a "norbornene ring" included in a norbornene-based monomer, one or a plurality of carbon atoms may be interposed between carbon-carbon single bonds that form the ring structure, and these interposed carbon atoms may form single bonds with one another, resulting in the formation of a new ring structure in the norbornene ring.

Examples of norbornene-based monomers include:.

Examples of possible substituents of the aforementioned derivatives include alkyl groups such as a methyl group and an ethyl group; alkenyl groups such as a vinyl group; alkylidene groups such as an ethylidene group and a propan-<NUM>-ylidene group; aryl groups such as a phenyl group; a hydroxy group; an acid anhydride group; a carboxyl group; and alkoxycarbonyl groups such as a methoxycarbonyl group.

Examples of monocyclic cycloolefin monomers include cyclic monoolefins such as cyclobutene, cyclopentene, methylcyclopentene, cyclohexene, methylcyclohexene, cycloheptene, and cyclooctene; and cyclic diolefins such as cyclohexadiene, methylcyclohexadiene, cyclooctadiene, methylcyclooctadiene, and phenylcyclooctadiene.

One of the cycloolefins described above may be used individually, or two or more of the cycloolefins described above may be used in combination. Note that in a case in which two or more cycloolefins are used, the cycloolefin ring-opened polymer may be a block copolymer or may be a random copolymer.

Of these examples, norbornene-based monomers are preferable, tricyclo[<NUM>. <NUM><NUM>,<NUM>]deca-<NUM>,<NUM>-diene and derivatives thereof, tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene and derivatives thereof, and <NUM>,<NUM>-benzotricyclo[<NUM>. <NUM><NUM>,<NUM>]dec-<NUM>-ene and derivatives thereof are more preferable, and tricyclo[<NUM>. <NUM><NUM>,<NUM>]deca-<NUM>,<NUM>-diene, tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene, and <NUM>,<NUM>-benzotricyclo[<NUM>. <NUM><NUM>,<NUM>]dec-<NUM>-ene are even more preferable as the cycloolefin.

Although no specific limitations are placed on the amount of a norbornene-based monomer that is used in production of the cycloolefin ring-opened polymer, the amount of the norbornene-based monomer per <NUM> mass% of the amount of all cycloolefin used in production of the cycloolefin ring-opened polymer is preferably <NUM> mass% or more, more preferably <NUM> mass% or more, and even more preferably <NUM> mass% (i.e., the cycloolefin ring-opened polymer is even more preferably a polymer obtained using only one or more norbornene-based monomers as monomers).

No specific limitations are placed on the method by which the cycloolefin ring-opened polymer is produced. For example, a known method in which a cycloolefin such as described above that is used as a monomer is ring-opening polymerized using a metathesis polymerization catalyst can be adopted. This method may, for example, be a method described in <CIT>.

The weight-average molecular weight (Mw) of the cycloolefin ring-opened polymer obtained as set forth above is not specifically limited but is preferably <NUM>,<NUM> or more, and more preferably <NUM>,<NUM> or more, and is preferably <NUM>,<NUM> or less, and more preferably <NUM>,<NUM> or less. When the weight-average molecular weight of the cycloolefin ring-opened polymer is <NUM>,<NUM> or more, it is possible to ensure sufficient strength of a barrel obtained through shaping of a resin that contains a hydrogenated product of the cycloolefin ring-opened polymer. On the other hand, when the weight-average molecular weight of the cycloolefin ring-opened polymer is <NUM>,<NUM> or less, it is possible to ensure sufficient formability of a resin that contains a hydrogenated product of the cycloolefin ring-opened polymer.

Moreover, the molecular weight distribution (Mw/Mn) of the cycloolefin ring-opened polymer is not specifically limited but is preferably not less than <NUM> and not more than <NUM>, and more preferably not less than <NUM> and not more than <NUM>. When the molecular weight distribution of the cycloolefin ring-opened polymer is within any of the ranges set forth above, a barrel having sufficient mechanical strength can be obtained.

Note that the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of a polymer such as a cycloolefin ring-opened polymer referred to in the present disclosure are standard polyisoprene-equivalent values according to gel permeation chromatography (GPC) with cyclohexane as an eluent.

The hydrogenated cycloolefin ring-opened polymer can be obtained by subjecting the cycloolefin ring-opened polymer described above to a hydrogenation reaction. No specific limitations are placed on the method by which the cycloolefin ring-opened polymer is hydrogenated. For example, a known method in which hydrogen is supplied into a reaction system in the presence of a hydrogenation catalyst can be adopted. This method may, for example, be a method described in <CIT>.

The percentage hydrogenation in the hydrogenation reaction (proportion of main chain carbon-carbon double bonds that are hydrogenated) is not specifically limited but is preferably <NUM>% or more, more preferably <NUM>% or more, even more preferably <NUM>% or more, and particularly preferably <NUM>% or more from a viewpoint of inhibiting the occurrence of burns and oxidative degradation during production of a barrel through shaping of the hydrogenated cycloolefin ring-opened polymer.

Note that the "percentage hydrogenation" in a hydrogenation reaction referred to in the present disclosure can be measured by nuclear magnetic resonance (NMR).

The weight-average molecular weight (Mw) of the hydrogenated cycloolefin ring-opened polymer obtained after the hydrogenation reaction described above is not specifically limited but is preferably <NUM>,<NUM> or more, and more preferably <NUM>,<NUM> or more, and is preferably <NUM>,<NUM> or less, and more preferably <NUM>,<NUM> or less. When the weight-average molecular weight of the hydrogenated cycloolefin ring-opened polymer is <NUM>,<NUM> or more, it is possible to ensure sufficient strength of a barrel obtained through shaping of a resin that contains the hydrogenated cycloolefin ring-opened polymer. On the other hand, when the weight-average molecular weight of the hydrogenated cycloolefin ring-opened polymer is <NUM>,<NUM> or less, it is possible to ensure sufficient formability of a resin that contains the hydrogenated cycloolefin ring-opened polymer.

Moreover, the molecular weight distribution (Mw/Mn) of the hydrogenated cycloolefin ring-opened polymer is not specifically limited but is preferably not less than <NUM> and not more than <NUM>, and more preferably not less than <NUM> and not more than <NUM>. When the molecular weight distribution of the hydrogenated cycloolefin ring-opened polymer is within any of the ranges set forth above, a barrel having sufficient mechanical strength can be obtained.

The copolymer of a cycloolefin and a chain olefin (hereinafter, also referred to simply as a "copolymer") is a polymer that is obtained through copolymerization of a cycloolefin as a monomer and a chain olefin as a monomer.

Any of the same cycloolefins as previously described in the "Hydrogenated cycloolefin ring-opened polymer" section can be used as the cycloolefin serving as a monomer used in production of the copolymer. One cycloolefin may be used individually, or two or more cycloolefins may be used in combination. Of these cycloolefins, bicyclo[<NUM>. <NUM>]hept-<NUM>-ene (common name: norbornene) and derivatives thereof, and tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene (common name: tetracyclododecene) and derivatives thereof are preferable, and bicyclo[<NUM>. <NUM>]hept-<NUM>-ene is more preferable.

A compound that has a chain structure formed of carbon atoms and includes a polymerizable carbon-carbon double bond in the chain structure can be used as the chain olefin serving as a monomer in production of the copolymer. Note that the term "chain olefin" as used in the present disclosure is not inclusive of compounds that are cycloolefins.

The chain olefin may, for example, be an α-olefin such as ethylene, propylene, <NUM>-butene, <NUM>-pentene, or <NUM>-hexene; an aromatic ring vinyl compound such as styrene or α-methylstyrene; or a non-conjugated diene such as <NUM>,<NUM>-hexadiene, <NUM>-methyl-<NUM>,<NUM>-hexadiene, <NUM>-methyl-<NUM>,<NUM>-hexadiene, or <NUM>,<NUM>-octadiene.

One chain olefin may be used individually, or two or more chain olefins may be used in combination. Of these examples, α-olefins are preferable, α-olefins having a carbon number of not less than <NUM> and not more than <NUM> are more preferable, and ethylene is even more preferable as the chain olefin.

No specific limitations are placed on the method by which the copolymer is produced. For example, a known method in which the cycloolefin and the chain olefin described above are addition polymerized using a polymerization catalyst can be adopted. This method may, for example, be a method described in <CIT>.

Although no specific limitations are placed on the ratio of amounts of the cycloolefin and the chain olefin used in production of the copolymer, the amount of the cycloolefin per <NUM> mass% of the total amount of the cycloolefin and the chain olefin used in production of the copolymer is preferably <NUM> mass% or more, more preferably <NUM> mass% or more, and even more preferably <NUM> mass% or more, and is preferably <NUM> mass% or less, more preferably <NUM> mass% or less, and even more preferably <NUM> mass% or less.

Note that the copolymer of the cycloolefin and the chain olefin may be a block copolymer or may be a random copolymer.

The weight-average molecular weight (Mw) of the copolymer of the cycloolefin and the chain olefin is not specifically limited but is preferably <NUM>,<NUM> or more, and more preferably <NUM>,<NUM> or more, and is preferably <NUM>,<NUM> or less, and more preferably <NUM>,<NUM> or less. When the weight-average molecular weight of the copolymer is <NUM>,<NUM> or more, it is possible to ensure sufficient strength of a barrel obtained through shaping of a resin that contains the copolymer. On the other hand, when the weight-average molecular weight of the copolymer is <NUM>,<NUM> or less, it is possible to ensure sufficient formability of a resin that contains the copolymer.

Moreover, the molecular weight distribution (Mw/Mn) of the copolymer is not specifically limited but is preferably not less than <NUM> and not more than <NUM>, and more preferably not less than <NUM> and not more than <NUM>. When the molecular weight distribution of the copolymer is within any of the ranges set forth above, a barrel having sufficient mechanical strength can be obtained.

The resin used to form the barrel contains either or both of a hydrogenated cycloolefin ring-opened polymer and a copolymer of a cycloolefin and a chain olefin as previously described, but preferably contains at least a hydrogenated cycloolefin ring-opened polymer. By using a barrel that is obtained through shaping of a resin containing at least a hydrogenated cycloolefin ring-opened polymer, it is possible to further inhibit protein aggregation in the protein solution formulation during long-term storage of the pre-filled syringe.

Examples of other components that can be contained in the resin used to form the barrel include polymer components (thermoplastic elastomers, etc.) other than the polymers described above and known additives. Examples of known additives that can be used include antioxidants, ultraviolet absorbers, light stabilizers, near-infrared absorbers, plasticizers, antistatic agents, acid scavengers, and the like described in <CIT>, for example.

The content of these other components in the resin can be set as appropriate depending on the objective of addition of the component. For example, in a case in which a thermoplastic elastomer is used, the used amount of the thermoplastic elastomer is preferably not less than <NUM> parts by mass and not more than <NUM> parts by mass when the total amount of the hydrogenated cycloolefin ring-opened polymer and the copolymer of a cycloolefin and a chain olefin is taken to be <NUM> parts by mass (i.e., when the amount of either of these polymers is taken to be <NUM> parts by mass in a case in which that polymer is used individually).

No specific limitations are placed on the method of mixing when obtaining the resin containing the above-described polymer(s) and other optional components. For example, mixing can be performed using a known melt-kneading machine such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneader, or a Feeder Ruder.

After mixing, the resin can be pelletized in accordance with a standard method by extruding the resin with a rod form and cutting the extruded resin to an appropriate length using a strand cutter.

No specific limitations are placed on the method by which the resin containing the components set forth above is shaped to obtain the barrel. For example, a barrel including a nozzle at a tip thereof can be shaped by a method described in the "Method of producing pre-filled syringe" section further below.

The barrel obtained as set forth above preferably includes a formulation contacting region having a water contact angle of <NUM>° or more at an inner wall surface thereof. When the water contact angle of a formulation contacting region is <NUM>° or more, protein aggregation in the protein solution formulation can be further inhibited during long-term storage of a pre-filled syringe that includes the barrel. From a viewpoint of even further inhibiting protein aggregation in the protein solution formulation, the water contact angle of the formulation contacting region is more preferably <NUM>° or more, even more preferably <NUM>° or more, and particularly preferably <NUM>° or more. The upper limit for the water contact angle of the formulation contacting region is not specifically limited but is normally <NUM>° or less.

Note that the water contact angle of the formulation contacting region can be adjusted by altering the types of polymers and additives contained in the resin used to form the barrel and the method by which the barrel is produced. For example, the value of the water contact angle of the formulation contacting region can be improved by using a hydrophobic polymer or additive (polymer or additive that does not include a hydrophilic group, for example). Moreover, the value of the water contact angle of the formulation contacting region can be improved by performing pre-drying described in the "Method of producing pre-filled syringe" section further below in advance of shaping the resin, for example.

The sealing member included in the presently disclosed pre-filled syringe is not specifically limited so long as it can prevent leakage of the protein solution formulation from the tip of the barrel and can be a known sealing member such as a cap or an injection needle. In the pre-filled syringe <NUM> illustrated in <FIG>, for example, a cap that fits with the nozzle <NUM> of the barrel <NUM> is included as the sealing member <NUM>.

No specific limitations are placed on the material from which the sealing member is formed. In a case in which the sealing member is a cap, for example, the sealing member can be formed using a known resin described in <CIT>.

The gasket included in the presently disclosed pre-filled syringe is not specifically limited so long as it can hermetically seal the protein solution formulation inside the barrel. It is preferable that at least a peripheral part of the gasket is formed of an elastic material. For example, the gasket may have a configuration including a core (not illustrated) that is formed of a rigid material and an elastic material disposed such as to cover the periphery of the core.

No specific limitations are placed on the material from which the gasket is formed. For example, elastic rubbers and synthetic resins described in <CIT> can be used.

The plunger included in the presently disclosed pre-filled syringe is a member that is linked to the gasket described above and that can move the gasket in a longitudinal direction inside the previously described barrel. In the pre-filled syringe <NUM> illustrated in <FIG>, for example, the plunger <NUM> includes a thumb pad <NUM> at the opposite end thereof to the gasket <NUM>, and a movement operation of the plunger <NUM> is performed by pressing the thumb pad <NUM> using a thumb or the like. As a result of the gasket <NUM> moving in accompaniment to a movement operation of the plunger <NUM>, the protein solution formulation <NUM> can be expelled externally from the nozzle <NUM> of the barrel <NUM>.

No specific limitations are placed on the material from which the plunger is formed. For example, a resin described in <CIT> can be used.

The presently disclosed pre-filled syringe set forth above can suitably be produced by the presently disclosed method of producing a pre-filled syringe, for example.

The presently disclosed method of producing a pre-filled syringe is a method of producing a pre-filled syringe having a protein solution formulation filled into an inner part of a syringe that includes: a barrel including a nozzle at a tip thereof; a sealing member sealing the nozzle; a gasket slidably housed inside the barrel; and a plunger linked to the gasket and performing a movement operation of the gasket in a longitudinal direction of the barrel. The presently disclosed method of producing a pre-filled syringe includes at least a step (filling step) of loading the protein solution formulation into the barrel to obtain a pre-filled syringe that is filled with the protein solution formulation. Features of the presently disclosed method of producing a pre-filled syringe are that the barrel is a shaped product of a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin, and that a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL is filled into a space defined by the sealing member, the gasket, and a region (formulation contacting region) that is part of an inner wall surface of the barrel.

A pre-filled syringe that is obtained by filling a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL into a barrel formed of a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin through the filling step set forth above can inhibit protein aggregation in the protein solution formulation and can limit the produced amount of a decomposition product of the non-ionic surfactant to a low level, even in a situation in which the pre-filled syringe is stored for a long time, for the same reason as previously described in the "Pre-filled syringe" section.

Note that the "nozzle", "barrel", "hydrogenated cycloolefin ring-opened polymer", "copolymer of a cycloolefin and a chain olefin", "resin", "sealing member", "gasket", "plunger", "protein solution formulation", and so forth in the following description are the same as previously described in the "Pre-filled syringe" section. In other words, specific examples, preferable examples, and so forth of the "nozzle", "barrel", "hydrogenated cycloolefin ring-opened polymer", "copolymer of a cycloolefin and a chain olefin", "resin", "sealing member", "gasket", "plunger", and "protein solution formulation" in the presently disclosed method of producing a pre-filled syringe are the same as the specific examples, preferable examples, and so forth of the "nozzle", "barrel", "hydrogenated cycloolefin ring-opened polymer", "copolymer of a cycloolefin and a chain olefin", "resin", "sealing member", "gasket", "plunger", and "protein solution formulation" in the presently disclosed pre-filled syringe set forth above, and thus description thereof is omitted in this section.

The method by which a protein solution formulation is loaded into the barrel such that a space defined by the sealing member, the gasket, and the formulation contacting region of the barrel inner wall surface is filled with a protein solution formulation having a non-ionic surfactant concentration within a specific range is not specifically limited and can be a known method such as described in <CIT>, for example. The filling step is preferably performed under sterilization.

The presently disclosed method of producing a pre-filled syringe can optionally include steps other than the filling step set forth above (i.e., other steps).

In the presently disclosed method of producing a pre-filled syringe, it is preferable that a series of operations that enable simple production of a barrel having a preferred inner wall surface property are performed before the filling step set forth above. Specifically, the presently disclosed method of producing a pre-filled syringe preferably includes, in advance of the filling step set forth above, a step (pre-drying step) of pre-drying the resin that serves as a shaping material, and a step (shaping step) of shaping the resin after the pre-drying to form the barrel.

By drying the resin that is used to form the barrel in advance of shaping the resin, the water contact angle of the surface of the barrel (particularly a formulation contacting region of the inner wall surface) can be improved, and protein aggregation in the protein solution formulation can be further inhibited. Note that although it is not clear why the water contact angle of the surface of the barrel that is obtained after shaping can be improved by drying the resin before shaping, it is presumed that the drying can reduce the oxygen concentration in the resin, and can thereby inhibit oxidation and hydrophilizing of the barrel surface due to heat during shaping.

Note that no specific limitations are placed on the shape of the resin during the pre-drying. The resin can have any shape such as a sheet shape or a pellet shape, but preferably has a pellet shape from a viewpoint of drying efficiency and ease of shaping.

The oxygen concentration in the resin after the pre-drying is preferably <NUM> mass ppm or less, more preferably <NUM> mass ppm or less, and even more preferably <NUM> mass ppm or less. When the oxygen concentration in the resin after the pre-drying is <NUM> mass ppm or less, the value of the water contact angle of the formulation contacting region of the barrel formed from the resin can be improved, and thus protein aggregation in the protein solution formulation can be further inhibited in a pre-filled syringe that includes the barrel.

The pre-drying is preferably performed in an inert gas atmosphere. By performing the pre-drying in an inert gas atmosphere, oxygen can be efficiently removed from the resin and oxidation of the resin due to external oxygen can be prevented. As a result, protein aggregation in the protein solution formulation can be further inhibited in a pre-filled syringe that includes the obtained barrel. Examples of inert gases that can be used include helium, argon, nitrogen, neon, krypton, and mixtures thereof.

The drying temperature (atmosphere temperature) of the pre-drying is preferably <NUM> or higher, more preferably <NUM> or higher, and even more preferably <NUM> or higher, and is preferably <NUM> or lower, and more preferably <NUM> or lower. When the drying temperature of the pre-drying is <NUM> or higher, oxygen can be efficiently removed from the resin, and, as a result, protein aggregation in the protein solution formulation can be further inhibited in a pre-filled syringe that includes the obtained barrel. On the other hand, when the drying temperature of the pre-drying is <NUM> or lower, curing of the resin prior to shaping can be prevented.

The drying time of the pre-drying is preferably <NUM> hour or more, more preferably <NUM> hours or more, and even more preferably <NUM> hours or more, and is preferably <NUM> hours or less, and more preferably <NUM> hours or less. When the drying time of the pre-drying is <NUM> hour or more, oxygen can be efficiently removed from the resin, and, as a result, protein aggregation in the protein solution formulation can be further inhibited in a pre-filled syringe that includes the obtained barrel. On the other hand, when the drying time of the pre-drying is <NUM> hours or less, oxidative degradation of the resin prior to shaping can be prevented.

The method by which the resin after the pre-drying set forth above is shaped to obtain a barrel of a desired shape is not specifically limited and can be a known shaping method such as injection molding, injection blow molding (cold parison method), or thermoforming. Of these methods, injection molding is preferable in terms that a target barrel can be efficiently produced.

In production of a barrel by injection molding, the resin is typically loaded into a hopper of an injection molding machine, is plasticized through heating inside a cylinder, and then molten resin (plasticized resin) is injected into a mold from an injection port. The molten resin cools and hardens inside the mold to thereby form the barrel.

The cylinder temperature during plasticizing of the resin is preferably not lower than <NUM> and not higher than <NUM>, more preferably not lower than <NUM> and not higher than <NUM>, and even more preferably not lower than <NUM> and not higher than <NUM>. When the cylinder temperature is <NUM> or higher, fluidity of molten resin is ensured, and sink marks and distortion do not arise in the barrel. On the other hand, when the cylinder temperature is <NUM> or lower, yellowing of the barrel and the occurrence of silver streaks due to thermal decomposition of the shaping material can be inhibited.

The injection rate during injection of the molten resin into the mold from the cylinder is preferably not less than <NUM><NUM>/s and not more than <NUM>,<NUM><NUM>/s. It is easier to obtain a barrel having excellent external shape when the injection rate is within the range set forth above. The injection pressure when the molten resin is injected into the mold from the cylinder is not specifically limited and can be set as appropriate in consideration of the type of mold, the fluidity of the molten resin, and so forth, but is normally not lower than <NUM> MPa and not higher than <NUM> MPa.

The mold temperature is normally a lower temperature than the glass-transition temperature (Tg) of the polymer (hydrogenated cycloolefin ring-opened polymer and/or copolymer of cycloolefin and chain olefin) in the resin, preferably a temperature that is <NUM> to <NUM> lower than Tg, and more preferably a temperature that is <NUM> to <NUM> lower than Tg. It is easier to obtain a barrel having little distortion when the mold temperature is within the range set forth above.

Note that the presently disclosed method of producing a pre-filled syringe can include a step of sterilizing the barrel, the gasket, and the sealing member before the filling step, for example, as another step besides the pre-drying step and the shaping step set forth above.

The following provides a more specific description of the present disclosure through examples. However, the present disclosure is not limited to these examples.

In the examples and comparative examples, the following methods were used to measure and evaluate the molecular weight, etc. (weight-average molecular weight, number-average molecular weight, and molecular weight distribution) of a polymer, the percentage hydrogenation in hydrogenation of a polymer, the glass-transition temperature of a polymer, the oxygen concentration in a resin, the water contact angle of a formulation contacting region at an inner wall surface of a barrel, the non-ionic surfactant concentration in a protein solution formulation after long-term storage of a pre-filled syringe (post-storage concentration), the occurrence of production of a decomposition product of a non-ionic surfactant in a protein solution formulation after long-term storage of a pre-filled syringe, and the inhibition of protein aggregation in a protein solution formulation after long-term storage of a pre-filled syringe.

The weight-average molecular weight (Mw) and the number-average molecular weight (Mn) of a polymer were measured as standard polyisoprene-equivalent values by gel permeation chromatography (GPC) with cyclohexane as a solvent. The molecular weight distribution (Mw/Mn) was calculated from the obtained values of Mw and Mn. An HLC-8320GPC (produced by Tosoh Corporation) was used as a measurement apparatus. The standard polyisoprene was standard polyisoprene (monodisperse) produced by Tosoh Corporation, and a total of <NUM> points corresponding to weight-average molecular weights (Mw) of <NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, <NUM>,<NUM>, and <NUM>,<NUM> were used. Measurement was performed with a TSKgel G5000HXL, a TSKgel G4000HXL, and a TSKgel G2000HXL (each produced by Tosoh Corporation) connected in series as a column and under conditions of a flow rate of <NUM>/min, a sample injection volume of <NUM>µmL, and a column temperature of <NUM>.

The percentage hydrogenation in a hydrogenation reaction was calculated through <NUM>H-NMR measurement with deuterated chloroform as a solvent.

Glass-transition temperature measurement was performed based on JIS K <NUM> using a differential scanning calorimeter (DSC6220 produced by SII NanoTechnology Inc.

A thermal desorption analyzer (produced by ESCO, Ltd. ; product name: WA1000S/W) was used to heat resin pellets at <NUM> for <NUM> minutes and to measure the amount of desorbed oxygen during this heating in order to calculate the oxygen concentration in the resin.

A barrel was cut by diagonal pliers to cut out a formulation contacting region of the barrel. A goniometer (produced by Kyowa Interface Science Co. ; product name: Drop Master <NUM>) was used to measure the static contact angle by a curve fitting method for <NUM> arbitrarily selected locations in the formulation contacting region, and an average value of the measured values was taken to be the water contact angle of the formulation contacting region.

A pre-filled syringe was left at rest in the dark at <NUM> for <NUM> week. After the pre-filled syringe had been left at rest for <NUM> week, the protein solution formulation inside the pre-filled syringe was pushed out from the nozzle by applying pressure to the plunger linked to the gasket, and the protein solution formulation was collected.

The non-ionic surfactant concentration in the protein solution formulation after long-term storage (post-storage concentration) was calculated by the following formula.

Note that A0 and A1 in the preceding formula are the area intensities of peaks attributed to a non-ionic surfactant that were obtained from data acquired through high-performance liquid chromatography (HPLC) analysis of the protein solution formulation before long-term storage and after long-term storage, respectively. The conditions under which HPLC was performed were as follows.

HPLC analysis of the protein solution formulation after long-term storage was performed under the same conditions as in "Post-storage concentration of non-ionic surfactant", and the presence or absence of a peak attributed to a decomposition product was checked. Note that a judgment of "Yes" for production of a decomposition product after storage was made in a case in which such a peak was observed, whereas a judgment of "No" for production of a decomposition product after storage (i.e., that the produced amount was below the limit of detection) was made in a case in which such a peak was not observed.

A pre-filled syringe was left at rest in the dark at <NUM> for <NUM> week. After the pre-filled syringe had been left at rest for <NUM> week, the protein solution formulation inside the pre-filled syringe was pushed out from the nozzle by applying pressure to the plunger linked to the gasket, and the protein solution formulation was collected. The number of aggregates having a particle diameter of <NUM> or more that were contained in the collected protein solution formulation was visually counted using a FlowCam <NUM> (Fluid Imaging Technologies, Scarborough, ME). Note that the sample volume was <NUM>, and analysis was performed at a flow rate of <NUM>/min. Data analysis was performed using Visual Spreadsheet Software (Fluid Imaging Technologies). The same operations were performed a total of four times. The number of aggregates per unit volume (aggregates/mL) was calculated for each repetition of the operations, and an average value of the calculated values was taken to be the post-storage aggregate concentration (aggregates/mL). A smaller value for the post-storage aggregate concentration can be said to signify that protein aggregation in the protein solution formulation during long-term storage of the pre-filled syringe is inhibited.

Purified Humira (adalimumab) was adjusted to a concentration of <NUM>/mL using phosphate buffered saline (pH: <NUM>; NaCl: <NUM>; phosphoric acid: <NUM>), and polysorbate <NUM> was added as a non-ionic surfactant such as to have a concentration of <NUM>/mL to obtain a protein solution formulation.

In a nitrogen atmosphere, <NUM> parts of <NUM>-hexene, <NUM> parts of dibutyl ether, and <NUM> parts of triisobutylaluminum were added to <NUM> parts of dehydrated cyclohexane in a reactor at room temperature and were mixed therewith. Thereafter, the mixture was held at <NUM> while <NUM> parts of tricyclo[<NUM>. <NUM><NUM>,<NUM>]deca-<NUM>,<NUM>-diene (common name: dicyclopentadiene; hereinafter, abbreviated as "DCP"), <NUM> parts of <NUM>-methyl-tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene, <NUM> parts of tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]trideca-<NUM>,<NUM>,<NUM>,<NUM>-tetraene (hereinafter, abbreviated as "MTF"), and <NUM> parts of tungsten hexachloride (<NUM>% toluene solution) were continuously added over <NUM> hours, concurrently to one another, and polymerization was carried out. Next, <NUM> parts of butyl glycidyl ether and <NUM> parts of isopropyl alcohol were added to the polymerization solution to deactivate the polymerization catalyst and stop the polymerization reaction. When the resultant reaction solution containing a ring-opened polymer was analyzed by gas chromatography, the polymerization conversion rate of monomers was <NUM>%.

Next, <NUM> parts of cyclohexane was added to <NUM> parts of the obtained reaction solution containing the ring-opened polymer, <NUM> parts of diatomite-supported nickel catalyst (nickel support rate: <NUM> weight%; pore volume: <NUM>/g; specific surface area: <NUM><NUM>/g) was further added as a hydrogenation catalyst, the pressure was raised to <NUM> MPa with hydrogen, heating was performed to a temperature of <NUM> under stirring, and then a reaction was carried out for <NUM> hours to obtain a reaction solution containing a hydrogenated DCP/<NUM>-methyl-tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene/MTF ring-opened copolymer. The hydrogenation catalyst was removed by filtration, and then cyclohexane serving as a solvent and other volatile components were removed from the solution at a temperature of <NUM> and a pressure of <NUM> kPa or lower using a cylindrical evaporator (produced by Hitachi, Ltd. Next, the hydrogenated product was extruded in a strand form from an extruder while in a molten state, was cooled, and was subsequently pelletized to obtain pellets. The hydrogenated cycloolefin ring-opened polymer (hydrogenated product A) that had been pelletized had an Mw of <NUM>,<NUM>, a molecular weight distribution (Mw/Mn) of <NUM>, a percentage hydrogenation of <NUM>%, and a Tg of <NUM>.

After mixing <NUM> parts of the hydrogenated product A obtained as described above and <NUM> parts of pentaerythritol tetrakis[<NUM>-(<NUM>,<NUM>-di-t-butyl-<NUM>-hydroxyphenyl)propionate] as an antioxidant using a blender, a twin-screw kneader for which hopper purging with nitrogen had been performed was used to knead and extrude the mixture at a cylinder temperature of <NUM> to obtain resin pellets.

A hot-air dryer was used to dry (pre-dry) the resin pellets obtained as described above in a nitrogen atmosphere under conditions of an atmosphere temperature of <NUM> and a drying time of <NUM> hours. The oxygen concentration of the resin after this pre-drying was measured. The result is shown in Table <NUM>.

The pre-dried resin was injection molded under the following conditions using an injection molding machine (produced by FANUC Corporation; product name: ROBOSHOT aS-50iA) in which a mold for a syringe molded product (syringe size: in accordance with <NUM>-Long size of ISO Standard <NUM>-<NUM>) was installed in order to produce a barrel of a syringe.

The water contact angle of a formulation contacting region of the obtained barrel was measured. The result is shown in Table <NUM>.

The barrel and the protein solution formulation described above were used to produce a pre-filled syringe having the configuration illustrated in <FIG> by the following procedure. Note that production of the pre-filled syringe was performed in a sterilized environment.

A cap made from isoprene rubber was attached to a tip of the obtained barrel, and <NUM> of the protein solution formulation was filled into the barrel. Next, a plunger having a gasket made from butyl rubber attached thereto was inserted from the base end of the barrel to hermetically seal the barrel and obtain a pre-filled syringe that was filled with the protein solution formulation. The obtained pre-filled syringe was used to evaluate the post-storage concentration of the non-ionic surfactant, occurrence of production of a decomposition product of the non-ionic surfactant, and inhibition of protein aggregation. The results are shown in Table <NUM>.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that polysorbate <NUM> was added as a non-ionic surfactant such as to have a concentration of <NUM>/mL in preparation of the protein solution formulation. The results are shown in Table <NUM>.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that a copolymer of a cycloolefin and a chain olefin (copolymer B) that was produced as described below was used instead of the hydrogenated cycloolefin ring-opened polymer (hydrogenated product A) in production of the barrel. The results are shown in Table <NUM>.

In a stream of nitrogen at normal temperature, norbornene (<NUM>) was added into a reactor that had been charged with <NUM> of cyclohexane and was stirred for <NUM> minutes. In addition, triisobutylaluminum was added such that the concentration thereof in the system was <NUM>/L. Next, ethylene was circulated at normal pressure while performing stirring in order to convert the system to an ethylene atmosphere. An autoclave internal temperature of <NUM> was maintained while raising the internal pressure to a gauge pressure of <NUM>/cm<NUM> with ethylene. After <NUM> minutes of stirring, <NUM> of a pre-prepared toluene solution containing isopropylidene(cyclopentadienyl)(indenyl)zirconium dichloride and methylalumoxane was added to initiate a copolymerization reaction of ethylene and norbornene. The catalyst concentration relative to the entire system at this point was <NUM> mmol/L of isopropylidene(cyclopentadienyl)(indenyl)zirconium dichloride and <NUM> mmol/L of methylalumoxane. Ethylene was continuously supplied into the system during the copolymerization reaction in order to maintain the temperature at <NUM> and the internal pressure at a gauge pressure of <NUM>/cm<NUM>. After <NUM> minutes, isopropyl alcohol was added to stop the copolymerization reaction. Depressurization was performed, and then a polymer solution was removed and was brought into contact with an aqueous solution of <NUM> of concentrated hydrochloric acid added to <NUM><NUM> of water under vigorous stirring in a ratio of <NUM>:<NUM> to cause catalyst residue to move into the aqueous phase. This contacted liquid mixture was left to settle, the aqueous phase was separated and removed, and washing with water was performed twice to purify and separate a polymerization liquid phase.

The polymerization liquid phase that had been purified and separated was then brought into contact with <NUM> equivalents of acetone under vigorous stirring to cause precipitation of a copolymer. Thereafter, solid (copolymer) was collected by filtration and was thoroughly washed with acetone. The solid was added into acetone in a concentration of <NUM>/m<NUM> and an extraction operation was subsequently performed under conditions of <NUM> hours at <NUM> in order to extract unreacted monomer. After this extraction, solid was collected by filtration and was dried under circulation of nitrogen at <NUM> and <NUM> mmHg for <NUM> hours to yield an ethylene-norbornene copolymer (copolymer B).

The ethylene-norbornene copolymer (copolymer B) was pelletized in the same way as the hydrogenated product A of Production Example <NUM>. The pelletized ethylene-norbornene copolymer (copolymer B) had a weight-average molecular weight (Mw) of <NUM>,<NUM>, a molecular weight distribution (Mw/Mn) of <NUM>, and a Tg of <NUM>.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that pre-drying was not performed in production of the barrel. The results are shown in Table <NUM>.

A barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that a protein solution formulation prepared as described below was used. The results are shown in Table <NUM>.

Purified Remicade (infliximab) was adjusted to a concentration of <NUM>/mL using phosphate buffered saline (pH: <NUM>; NaCl: <NUM>; phosphoric acid: <NUM>), and polysorbate <NUM> was added as a non-ionic surfactant such as to have a concentration of <NUM>/mL to obtain a protein solution formulation.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that a copolymer of a cycloolefin and a chain olefin (copolymer B) that was produced in the same way as in Example <NUM> was used instead of the hydrogenated cycloolefin ring-opened polymer (hydrogenated product A) in production of the barrel. The results are shown in Table <NUM>.

Purified Humira (adalimumab) was adjusted to a concentration of <NUM>/mL using phosphate buffer solution (pH: <NUM>; NaCl: <NUM>; phosphoric acid: <NUM>), and polysorbate <NUM> was added as a non-ionic surfactant such as to have a concentration of <NUM>/mL to obtain a protein solution formulation.

Purified Humira (adalimumab) was adjusted to a concentration of <NUM>/mL using a solution produced by adding NaCl to acetate buffer solution (pH: <NUM>; acetic acid: <NUM>) such as to have a concentration of <NUM> (NaCl concentration), and polysorbate <NUM> was added as a non-ionic surfactant such as to have a concentration of <NUM>/mL to obtain a protein solution formulation.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that a hydrogenated cycloolefin ring-opened polymer (hydrogenated product C) that was produced as described below was used instead of the hydrogenated cycloolefin ring-opened polymer (hydrogenated product A) in production of the barrel. The results are shown in Table <NUM>.

In a nitrogen atmosphere, <NUM> parts of <NUM>-hexene, <NUM> parts of dibutyl ether, and <NUM> parts of triisobutylaluminum were added to <NUM> parts of dehydrated cyclohexane in a reactor at room temperature and were mixed therewith. Thereafter, the mixture was held at <NUM> while <NUM> parts of tricyclo[<NUM>. <NUM><NUM>,<NUM>]dec-<NUM>-ene (hereinafter, abbreviated as "DCPD"), <NUM> parts of <NUM>-ethyl-tetracyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM><NUM>,<NUM>]dodec-<NUM>-ene (hereinafter, abbreviated as ETCD), and <NUM> parts of a <NUM>% toluene solution of tungsten hexachloride were continuously added over <NUM> hours and polymerization was carried out. The resultant polymerization reaction liquid was transferred to a pressure-resistant hydrogenation reactor, <NUM> parts of diatomite-supported nickel catalyst (G-96D produced by Nissan Girdler Catalyst Company; nickel support rate: <NUM> weight%) and <NUM> parts of cyclohexane were added, and a reaction was carried out at <NUM> and a hydrogen pressure of <NUM> kgf/cm<NUM> for <NUM> hours. Diatomite as a filter aid was laid on a stainless steel screen of a filtration apparatus, and then the hydrogenation reaction liquid was filtered to remove the catalyst. A hydrogenated product was caused to precipitate by pouring the filtered reaction solution into <NUM>,<NUM> parts of isopropyl alcohol under stirring and was then separated by filtration and collected. The obtained hydrogenated product was washed with <NUM> parts of acetone and was subsequently dried in a vacuum dryer set to <NUM> torr or lower and <NUM> for <NUM> hours to yield <NUM> parts of a hydrogenated cycloolefin ring-opened polymer (hydrogenated product C).

The hydrogenated cycloolefin ring-opened polymer (hydrogenated product C) was pelletized in the same way as the hydrogenated product A of Production Example <NUM>. The hydrogenated cycloolefin ring-opened polymer (hydrogenated product C) that had been pelletized had an Mw of <NUM>,<NUM>, a molecular weight distribution (Mw/Mn) of <NUM>, a percentage hydrogenation of <NUM>%, a Tg of <NUM>, and a copolymerization composition (weight ratio) of DCPD/ETCD = <NUM>/<NUM>.

A protein solution formulation was prepared, a barrel and a pre-filled syringe were produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that <NUM> parts of an aromatic vinyl-conjugated diene block copolymer "Tuftec® H1043" (Tuftec is a registered trademark in Japan, other countries, or both; produced by Asahi Kasei Corporation) and <NUM> parts of an aromatic vinyl-conjugated diene block copolymer "Tuftec® H1051" (produced by Asahi Kasei Corporation) were added as stabilizers (thermoplastic elastomers) when obtaining resin pellets. The results are shown in Table <NUM>.

A protein solution formulation was prepared, a pre-filled syringe was produced, and various evaluations were performed in the same way as in Example <NUM> with the exception that a barrel made from glass was used as the barrel. The results are shown in Table <NUM>.

A protein solution formulation was prepared, a pre-filled syringe was produced, and various evaluations were performed in the same way as in Comparative Example <NUM> with the exception that a barrel made from glass was used as the barrel. The results are shown in Table <NUM>.

It can be seen from Tables <NUM> and <NUM> that the pre-filled syringes of Examples <NUM> to <NUM>, which were each obtained by filling a protein solution formulation having a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL into a barrel formed of a resin containing a hydrogenated cycloolefin ring-opened polymer and/or a copolymer of a cycloolefin and a chain olefin, could inhibit protein aggregation in the protein solution formulation and limit the produced amount of a decomposition product of the non-ionic surfactant to a low level in a situation in which the pre-filled syringe was stored for a long time.

On the other hand, it can be seen from Tables <NUM> and <NUM> that the pre-filled syringes of Comparative Examples <NUM> to <NUM> and <NUM> to <NUM> in which a protein solution formulation having a non-ionic surfactant concentration of <NUM>/mL or more was used could not limit the produced amount of a decomposition product of the non-ionic surfactant to a low level after long-term storage.

It can also be seen from Tables <NUM> and <NUM> that protein aggregation after long-term storage could not be inhibited in the pre-filled syringes of Comparative Examples <NUM> to <NUM> and <NUM> to <NUM> in which a barrel formed of glass was used.

According to the present disclosure, it is possible to provide a pre-filled syringe that can inhibit protein aggregation in a protein solution formulation while also reducing the produced amount of a decomposition product of a non-ionic surfactant after long-term storage.

Claim 1:
A pre-filled syringe (<NUM>) comprising:
a barrel (<NUM>) including a nozzle at a tip thereof;
a sealing member (<NUM>) sealing the nozzle (<NUM>);
a gasket (<NUM>) slidably housed inside the barrel;
a plunger (<NUM>) linked to the gasket and performing a movement operation of the gasket in a longitudinal direction of the barrel; and
a protein solution formulation (<NUM>) filled into a space defined by the sealing member, the gasket, and a region (<NUM>) that is part of an inner wall surface (<NUM>) of the barrel, characterized in that
the barrel is formed of a resin containing either or both of a hydrogenated cycloolefin ring-opened polymer and a copolymer of a cycloolefin and a chain olefin, and the region that is part of the inner wall surface has a water contact angle of <NUM>° or more, and
the protein solution formulation has a non-ionic surfactant concentration of more than <NUM>/mL and less than <NUM>/mL.