HK1240152B - Botulinum toxin prefilled container - Google Patents

Description

Botulinum toxin prefilled containers

Technical Field

The present invention relates to a prefilled plastic container, such as a prefilled plastic syringe, containing an aqueous botulinum toxin formulation. The aqueous botulinum toxin formulation in the prefilled plastic container is stable over the long term. Furthermore, the present invention relates to a kit comprising the prefilled plastic container and to the use of the prefilled plastic container for therapeutic and cosmetic purposes.

Background Art

Botulinum toxin (BoNT) is one of the most potent toxins known and acts by blocking the release of acetylcholine from peripheral cholinergic neurons. BoNT is synthesized as a 150 kDa precursor neurotoxic polypeptide and activated by selective proteolytic cleavage to produce the active two-chain BoNT form, which comprises a 100 kDa heavy chain (HC; including the transport and receptor binding domains) and a 50 kDa light chain (LC; including the catalytic domain), linked by disulfide bonds and non-covalent interactions. There are eight homologous serotypes of botulinum toxin (A, B, _C1 , _C2 , D, E, F, and G), which are produced by the bacterium Clostridium botulinum as a complex containing the neurotoxic polypeptide and other (non-toxic) clostridial proteins (i.e., different hemagglutinins and non-toxic, non-hemagglutinin proteins).

Careful administration of very small doses of the toxin can limit its effects somewhat, reducing overactive muscles and exocrine glands. Consequently, botulinum toxin is currently used to treat a variety of debilitating neuromuscular disorders (e.g., cervical dystonia, blepharospasm, and spasticity), overactive exocrine glands (e.g., excessive sweating and salivation), and other conditions, as well as for cosmetic purposes (e.g., treatment of facial wrinkles).

Botulinum toxin is naturally unstable, particularly known to be highly unstable at alkaline pH and thermally unstable. In addition, it is known that there are significant difficulties in diluting isolated toxin complexes from milligram amounts to much lower toxin concentrations (in the range of nanograms per milliliter) for use in injection solutions, as such large dilutions can result in the rapid loss of specific toxicity. This results in the loss of biological activity during production, reconstitution and/or storage of protein-containing pharmaceutical compositions. These problems observed in proteins can be attributed to chemical instability leading to bond formation or cleavage (e.g., hydrolysis, oxidation, racemization, β-elimination, and disulfide exchange), and/or to physical instability of the secondary or higher order structures of proteins that have not been modified by covalent bond cleavage (e.g., denaturation, adsorption to surfaces, and non-covalent spontaneous aggregation).

However, drug product stability is crucial to ensuring safe and effective use over a sufficient period of time. Because aqueous botulinum toxin preparations are particularly susceptible to degradation, commercial botulinum toxin preparations are typically vacuum-dried or freeze-dried. Examples include onabotulinumtoxinA (Allergan, Inc.) and abobotulinumtoxinA (Ipsen, Ltd.), both of which contain the botulinum toxin type A complex. Another example is incobotulinumtoxin (Merz Pharma GmbH & Co. KGaA), which contains the pure neurotoxic component of serotype A (i.e., the 150 kDa neurotoxic polypeptide) and is free of any other proteins of the botulinum toxin complex (i.e., the various hemagglutinins and the nontoxic, non-hemagglutinin proteins).

Although lyophilized materials have increased stability, they must typically be reconstituted with a pharmaceutically acceptable liquid (e.g., normal saline) before use. Therefore, lyophilized drug products are considered less convenient than other dosage forms. Furthermore, the reconstitution process carries the risk of improper handling leading to inaccurate dosages or sterility issues. Furthermore, the lyophilization process is time-consuming and results in additional costs.

Another drawback of reconstituted botulinum toxin solutions is that they are often not fully usable, as not every patient and every indication requires the same dose. Unfortunately, due to the instability of reconstituted toxin solutions, they can only be stored and reused within a relatively short timeframe. For example, prior to use, dilution of ® and ® with normal saline is recommended within 6 and 4 hours, respectively. Similarly, the package insert for ® states that reconstituted solutions should not be used after storage for more than 24 hours.

A dosage form that overcomes most of these drawbacks is the prefilled syringe format, which has become increasingly popular as a drug delivery device in recent years. However, if proteins are used as the active ingredient, their limited stability makes the use of prefilled syringes a particularly challenging task for formulation scientists. In particular, this format is suitable for extremely dilute aqueous botulinum toxin solutions.

To increase the stability of solid or liquid pharmaceutical botulinum toxin compositions, stabilizing proteins, such as human serum albumin (HSA), are often added. Furthermore, it is known to add non-protein stabilizers, such as surfactants, polyvinylpyrrolidone (PVP), disaccharides, polyols, and the like. However, the stability of liquid botulinum toxin formulations remains unsatisfactory, and/or their stability is achieved by injecting substances that are undesirable to humans (see, for example, WO 01/58472, WO 2006/005910, and WO 2007/041664).

Furthermore, WO 00/15245 discloses a highly concentrated liquid formulation of botulinum toxin type B (approximately 2500 U/ml) that is stable for up to 30 months when stored in glass vials at 5° C. However, this stability is only achieved by using vials made of glass and buffering the pH of the solution down to an acidic pH between 5 and 6, which can cause pain during injection.

Despite significant progress in this area, there is currently no injectable botulinum toxin formulation that is not only stable over time to provide a sufficiently long shelf life, but also convenient and easy to use, reduces medication errors, and minimizes the risk of contamination.

Purpose of the Invention

In view of the above circumstances, an object of the present invention is to provide a stable pharmaceutical dosage form for administering botulinum toxin in a convenient, safe, and simple manner.

Summary of the Invention

The above objects are achieved by providing a botulinum toxin pre-filled plastic container (e.g., syringe, vial, carpule, or ampoule) wherein the liquid botulinum toxin formulation in the pre-filled plastic container (e.g., syringe, vial, carpule, or ampoule) is long-term stable at 2-8° C. to provide a sufficiently long shelf life (at least about 12-24 months).

In a first aspect, the present invention provides a pre-filled plastic container (e.g., a syringe, vial, carpule, or ampoule) comprising an aqueous botulinum toxin formulation, wherein the toxin activity does not decrease by more than 25% relative to the initial toxin activity when the pre-filled container is stored under the following conditions: (a) at 5°C for 12 months or (b) at 25°C for 3 months.

The stability of the aqueous botulinum toxin formulation in the prefilled container (e.g., syringe, vial, carpule, or ampoule) is also excellent in terms of microscopic particle counts (numbers) equal to or greater than 10 μm, and is generally less than 1000/ml during storage at 2-25° C. (e.g., 5° C. or 25° C.) for 6 to 24 months (e.g., 6, 9, 12, 15, 18, or 24 months). Furthermore, the aqueous botulinum toxin formulation in the prefilled container exhibits excellent pH stability, specifically, the pH does not increase or decrease by more than 10% relative to the initial pH value during storage of the prefilled container (e.g., syringe, vial, carpule, or ampoule) at 2-25° C. (e.g., 5° C. or 25° C.) for 6 to 24 months (e.g., 6, 9, 12, 15, 18, or 24 months).

In another aspect, the present invention provides a kit comprising a pre-filled plastic container (eg, a syringe, a vial, a carpule, or an ampoule) according to the first aspect of the invention, and optionally instructions for use of the pre-filled plastic container.

In another aspect, the present invention provides a pre-filled plastic container (e.g., a syringe, a vial, a carple bottle, or an ampoule) for use in treatment according to the first aspect of the present invention. For example, the pre-filled plastic container (e.g., a syringe, a vial, a carple bottle, or an ampoule) can be used to treat a disease or condition caused by or associated with overactive cholinergic innervation of a patient's muscles or exocrine glands, including but not limited to dystonia, rigidity, hypertonia, dysfunction, focal spasm, strabismus, tremor, cramps, migraine, drooling, and hyperhidrosis.

In another aspect, the present invention relates to the use of a prefilled plastic container (e.g., a syringe, a vial, a carpule, or an ampoule) according to the first aspect of the invention in cosmetic applications, such as for treating skin wrinkles and facial asymmetries, e.g., glabellar frown lines, crow's feet, upper facial wrinkles, and platysma bands.

In yet another aspect, the present invention provides a method for treating a disease or condition caused by or associated with overactive cholinergic innervation of a patient's muscles or exocrine glands, the method comprising topically administering an effective amount of botulinum toxin to the patient's muscles or exocrine glands by injection using a prefilled plastic container (e.g., a syringe, vial, carpule, or ampoule) according to the first aspect of the invention.

In yet another aspect, the present invention relates to a method for cosmetic treatment of the skin, such as for treating skin wrinkles and facial asymmetry, comprising topically administering to a patient an effective amount of botulinum toxin by intradermal, subdermal or subcutaneous injection using a prefilled plastic container (e.g., a syringe, vial, carpule or ampoule) according to the first aspect of the invention.

Further embodiments of the invention are set forth in the accompanying dependent claims.The invention may be more fully understood with reference to the following detailed description, examples and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the stability of liquid botulinum toxin formulations in pre-filled syringe configurations A (·) and B (o) at 5°C as a function of toxin potency versus time.

DETAILED DESCRIPTION

The present invention is based on the unexpected discovery that liquid botulinum toxin formulations in plastic containers (e.g., in the form of syringes, vials, carpules, or ampoules) exhibit excellent long-term stability at reduced temperatures (e.g., 2-8° C.). Even when stored at ambient temperature (e.g., 25° C.), botulinum toxin prefilled containers exhibit surprisingly high stability.

Therefore, compared with other administration forms, the pre-filled container of the liquid botulinum toxin formulation of the present invention, in particular the pre-filled syringe of the botulinum toxin of the present invention, not only has a sufficiently long shelf life (at least about 12-24 months), but also presents a number of additional advantages, such as ease of use and convenience, reduced risk of medication errors, high dosage accuracy, low risk of contamination, improved sterility assurance, and high safety of administration.

Additionally, the use of plastic materials for containers (e.g., syringes) offers advantages over glass containers (e.g., glass syringes) in terms of resistance to breakage, reduced weight, increased flexibility for novel shapes of the original container, improved dimensional tolerances, and the absence of undesirable substances (e.g., adhesives).

Plastic materials contain various substances and additives (e.g., plasticizers) (commonly referred to as leachables/extractables), which are known to easily destabilize proteins, particularly when the proteins are fragile and/or used as neurotoxins (such as botulinum toxin) at very low concentrations. Consequently, liquid neurotoxin pharmaceutical formulations are typically injected using glass syringes. Surprisingly, however, it was discovered that the prefilled plastic container (e.g., syringe) according to the present invention provides stability for aqueous botulinum toxin formulations stored for extended periods of time (at least about 12-24 months) at 2-8°C, thereby providing a sufficiently long shelf life.

As used herein, a "pre-filled container" refers to any device having a partially or completely enclosed space that can be sealed or is sealed and can be used to contain, store and/or transport a liquid formulation. Within the meaning of the present invention, a "pre-filled container" is preferably a closed (or sealed) container made of plastic, or partially or mainly made of plastic (e.g., an organic polymer), and includes, for example, containers in the form of (i) syringes, (ii) vials, (iii) carpules, or (iv) ampoules.

Pre-filled syringe and carple bottle have two openings, and it is sealed to prevent content (for example, aqueous preparation) from leaking.With regard to pre-filled syringe, proximal end is sealed by plunger stopper, and distal end is sealed by capping device, as described in detail below.With regard to plastic carple bottle, it is generally the plastic column that is aseptically filled with pharmaceutical preparation, and proximal end is sealed by rubber stopper usually.This rubber stopper can be pressed into by the pressure of carple syringe puncture, as the piston in column.The distal end is sealed by puncture membrane usually.Puncture membrane is punctured for injection.

Within the meaning of the present invention, a "vial" is a vessel that is generally tubular or flask-shaped and is suitable for containing, storing and/or transporting a pharmaceutical preparation. The single opening can be sealed by different vial closure systems. For example, vials can be closed with screw caps (screw-top vials), cork stoppers, plastic or rubber (lip-top vials and crimp-top vials), and other closure systems such as flip-top or snap-top caps. In the present invention, a "vial" preferably means a plastic vessel whose opening is sealed by a vial closure system.

The present invention is described in further detail below. It should be noted that although the terms "prefilled syringe", "prefilled plastic syringe", "syringe" or "plastic syringe" are used in specific embodiments of the present invention, this is not intended to limit the specific embodiment of the (plastic) syringe as the (plastic) container. In fact, unless otherwise specified, any reference to "prefilled syringe", "prefilled plastic syringe", "syringe" or "plastic syringe" in this document should be understood as a reference to and disclosure of "container" or "plastic container", and also includes or discloses "vial" or "plastic vial", "carpule" or "plastic carpule", or "ampoule" or "plastic ampoule".

In a first aspect, the present invention relates to a prefilled plastic syringe comprising a botulinum toxin in the form of an aqueous formulation, wherein the toxin activity decreases by no more than 25% relative to the initial toxin activity when the prefilled syringe is stored: (a) at standard refrigerated temperature (i.e., 2-8° C., such as 5° C.) for 12 months, or (b) at 25° C. for 3 months. Preferably, the toxin activity decreases by no more than 20%, 15%, 10%, or 5% relative to the initial toxin activity after 12 months of storage of the prefilled syringe at 2-8° C. (e.g., 5° C.), or by no more than 20% relative to the initial toxin activity after 3 months of storage of the prefilled syringe at 25° C. More preferably, the toxin activity decreases by no more than 15%, 10%, or 5% relative to the initial toxin activity after 6 months of storage of the prefilled syringe at 2-8° C. (e.g., 5° C.).

Surprisingly, the aqueous botulinum toxin formulation in the prefilled syringe is stable even over a storage period of up to 24 months. For example, when stored at 2-8° C. (e.g., 5° C.) for up to 24 months (e.g., 15, 18, or 24 months), the toxin activity preferably decreases by no more than 30% or 25%, more preferably by no more than 20%, in particular by no more than 15%, particularly preferably by no more than 10%, and most preferably by no more than 5% relative to the initial toxin activity.

As used herein, the term "toxin potency" broadly refers to a measure of the activity of a drug (e.g., botulinum toxin) expressed as the amount required to produce an effect of a given intensity. As used herein, the terms "activity" or "toxin activity" refer to the biological activity of a botulinum toxin, where "biological activity" can refer to (a) receptor binding, (b) internalization, (c) transport across the endosomal membrane into the cytoplasmic matrix, and/or (d) endoproteolytic cleavage of proteins involved in synaptic vesicle fusion. For example, within the scope of the present invention, any light chain (LC) domain that exhibits proteolytic activity greater than 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or up to 100% of that of a corresponding wild-type LC domain in a SNAP-25 assay can be considered "biologically active" or "exhibits proteolytic activity." Furthermore, any heavy chain (HC) domain is considered "biologically active" if it is able to bind to a cellular HC domain receptor, particularly its native HC domain receptor, and is able to transport the LC domain to which it is associated.

Biological activity is generally expressed herein in mouse units (MU). As used herein, 1 MU is the amount of a neurotoxic component that kills 50% of a particular mouse population after intraperitoneal injection (i.e., mouse ip _LD50 ), as measured according to the method of Schantz and Kauter (Schantz and Kauter, J. Assoc. Off. Anal. Chem. 1978, 61: 96-99). The terms "MU" and "unit" or "U" are used interchangeably herein.

Suitable assays for determining potency or biological activity include the mouse hemidiaphragm assay (MHA) (described in Pearce et al., Toxicol. Appl. Pharmacol. 128:69-77, 1994 and Pearce et al., Exp. Neurol. 147:96-10, 1997), the mouse diaphragm assay (MDA) (performed according to Dressler et al., Mov. Disord. 20:1617-1619, 2005), the SNAP-25 protease assay (e.g., WO 2005). 2006/020748 or the “Improved SNAP25 endopeptidase immunoassay” described in Jones et al., J. Immunol. Methods 329:92-101, 2008), the electrochemiluminescence (ECL) sandwich ELISA described in WO 2009/114748, and the cell-based assays described in WO 2009/114748, WO 2004/029576, WO 2013/049508, and WO 2014/207109.

As used herein, the term "initial toxin activity" or "initial toxin potency" generally refers to the activity of the botulinum toxin at the beginning of the storage period (i.e., after the production of the final botulinum toxin prefilled syringe, for example, within one week or less after production). Additionally, as used herein, the term "after storage" is intended to mean after or at the end of a given storage period. Furthermore, the term "during storage" generally refers to the entire storage period.

In addition to having high stability in terms of toxin potency, aqueous botulinum toxin formulations are also highly stable in terms of microscopic particle counts. Within the meaning of the present invention, "microscopic particles" are generally particles with a diameter of less than 100 μm. According to the present invention, the microscopic particle count, more specifically the count (or number) of particles equal to or greater than 10 μm, in aqueous botulinum toxin formulations is generally less than 1000/ml, preferably less than 600/ml, and more preferably less than 200/ml during storage at 2-25°C (e.g., 5°C or 25°C) for 6 to 24 months (e.g., 6, 9, 12, 15, 18, or 24 months).

Particle number measurement can be performed using different methods, such as microfluidic imaging (MFI), resonant mass measurement (RMM) and nanoparticle tracking analysis (NTA). Particle measurement generally follows USP <788>. In the context of the present invention, microfluidic imaging methods are preferably used. This measurement method can be performed, for example, using a DPA-5200 particle analyzer system (ProteinSimple, Santa Clara, CA, USA) equipped with a silane-coated high-resolution 100 μm flow cell. Generally, samples are analyzed without dilution.

Alternatively, the number of particles can be determined by resonant mass measurement (RMM) using, for example, an ARCHIMEDES Particle Metrology System (Affinity Biosensors, Santa Barbara, CA, USA) equipped with a microsensor (size range of 0.3-4 μm) calibrated with a 1 μm polystyrene standard. All samples are typically analyzed without dilution. ParticleLab software (v1.8.570) can be used to analyze the results with a bin step size of 10 nm. As another alternative to determining the number of particles, nanoparticle tracking analysis (NTA) can be performed, for example, using a NanoSight LM20 system (NanoSight, Amesbury, UK). Samples are typically measured without dilution. The movement of particles in the sample can be recorded as a 60-second video at ambient temperature and analyzed with appropriate software (e.g., NTA 2.3 software).

In addition, the aqueous botulinum toxin formulation exhibits high pH stability, i.e., the pH is substantially stable during storage in the pre-filled syringe. Preferably, the pH does not increase or decrease by more than 10%, 8%, or 6% relative to the initial pH value when the pre-filled syringe is stored at 2-25°C (e.g., 5°C or 25°C) for 6 to 24 months (e.g., 6, 9, 12, 15, 18, or 24 months), for example, 18 months at 25°C or 24 months at 25°C. The pH can be measured according to the United States Pharmacopoeia Standard Test Method USP <791>, which outlines pH measurements for many pharmaceutical products. A suitable pH meter, such as the Lab 870 pH meter from Schott Instruments, can be used.

As used herein, the term "prefilled syringe" refers to a syringe that is filled with a pharmaceutical composition (i.e., an aqueous botulinum toxin formulation) before being distributed to an end user who will administer the drug to a patient. As used herein, the term "aqueous formulation" is intended to refer to an aqueous solution, suspension, dispersion, or emulsion, and preferably refers to an aqueous solution. Generally speaking, a prefilled syringe includes: a drug-containing container that forms part of the syringe body (i.e., syringe barrel); a plunger that seals the proximal end opening of the syringe and is used to expel the drug; and a sealing device (e.g., a tip cap or needle cover) on the syringe outlet end (e.g., the open end of the syringe tip or a preloaded needle (cannula)) that seals the distal end outlet opening. Within the meaning of the present invention, the term "prefilled plastic syringe" refers to a prefilled syringe where at least the barrel is made of plastic.

In the present invention, the prefilled syringe is preferably a straight-mouth (Luer slip) or screw-mouth (Luer lock) syringe equipped with a tip cap (if the needle is not pre-installed) or a needle cover (if the needle is pre-installed). Within the meaning of the present invention, a "straight-mouth syringe" is a syringe that allows the needle to be pushed to the end of the tip, while a "screw-mouth syringe" is a syringe that allows the needle to be rotated onto the tip and locked in place. This provides a reliable connection and avoids accidental removal of the needle that is injecting liquid.

The pre-filled plastic syringes according to the present invention are typically sterilized (e.g., by gamma irradiation, ethylene oxide (ETO) treatment, and moist heat (e.g., autoclaving). Sterilization can be performed before aseptic filling with the aqueous botulinum toxin formulation or after filling with the aqueous botulinum toxin formulation. The final pre-filled plastic syringe is ready for use. Furthermore, the pre-filled syringes described herein are typically intended for single use and are intended to be disposable. Prior to sterilization, the inner surface of the plastic syringe barrel is typically coated with a lubricant to facilitate sliding of the plunger stop and extrusion of the syringe contents.

According to the present invention, the aqueous botulinum toxin formulation in the pre-filled plastic syringe contains, for example, a botulinum toxin concentration of 1 U/ml to 3000 U/ml or 10 U/ml to 1000 U/ml. Preferably, the botulinum toxin is present in a concentration of about 10 U/ml to 400 U/ml, more preferably about 25 U/ml to 200 U/ml, and most preferably about 40 U/ml to 150 U/ml (e.g., 50 U/ml, 75 U/ml, or 100 U/ml).

As used herein, the term "botulinum toxin" refers broadly to any form and/or type of botulinum toxin. More specifically, the botulinum toxin can be selected from botulinum toxin types A, B, C1, C2, D, E, F, G, or mixtures thereof. Preferably, the botulinum toxin is serotype A, B, or C1, particularly serotype A.

In addition, the term "botulinum toxin" is intended to include both the botulinum toxin complex ("toxin complex") and the "neurotoxic component" of the botulinum toxin (complex). As used herein, the term "botulinum toxin complex" or "toxin complex" refers to a high molecular weight complex that includes the approximately 150 kDa neurotoxic component and (among other things) non-toxic proteins of Clostridium botulinum (including hemagglutinin and non-hemagglutinin proteins). Botulinum toxin serotype A complex is commercially available, for example, as ABBOX® (Allergan, Inc.) or ABBOX® (Ipsen, Ltd.).

As used herein, the term "neurotoxic component" relates to the neurotoxic polypeptide (the "150 KDa" polypeptide; typically in its two-chain form) of the toxin complex without any associated non-toxic proteins. Pure neurotoxic components are commercially available, for example, under the trade names VIZOL® and VIZOL® (Merz Pharmaceuticals GmbH). Preferably, the term "botulinum toxin" refers to the neurotoxic component of the botulinum toxin complex of a given serotype (e.g., serotype A, B, or C1, in particular serotype A). In other words, the aqueous botulinum toxin formulation contained in the pre-filled plastic syringe preferably contains (only) the neurotoxic component and does not contain any other proteins of the botulinum toxin complex.

It is also contemplated that the present invention encompasses functional (i.e., biologically active) isomers, homologs, orthologs, paralogs, and fragments of botulinum toxin that exhibit at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, and up to 60%, up to 70%, up to 80%, up to 90%, and up to 99% sequence identity to the amino acid sequence of wild-type botulinum toxin (such as wild-type botulinum toxin A or the neurotoxic component of serotype A1 botulinum toxin deposited in the GenBank database under Accession No. AAA23262). Sequence identity can be calculated by any algorithm suitable for producing reliable results, for example, by using the FASTA algorithm (W. R. Pearson & D. J. Lipman, PNAS 85: 2444-2448, 1988). Sequence identity can be calculated by comparing two polypeptides or two domains thereof (such as two LC domains or fragments thereof).

Modified and recombinant botulinum toxins are also within the scope of the present invention. For suitable mutants, reference is made to WO 2006/027207, WO 2009/015840, WO 2006/114308, WO 2007/104567, WO 2010/022979, WO 2011/000929, and WO 2013/068476, which are incorporated herein by reference. Furthermore, the present invention relates to chemically modified botulinum toxins, for example, by pegylation, glycosylation, sulfation, phosphorylation, or any other modification, particularly modification of one or more surface or solvent-exposed amino acids. The modified recombinant isomers, homologs, orthologs, paralogs, fragments and mutants suitable for use in the present invention are biologically active, i.e., they are capable of translocating into the cytoplasmic matrix of presynaptic cholinergic neurons and cleaving proteins of the SNARE complex (e.g., VAMP/syntaxin, synaptobrevin and SNAP-25), exerting their acetylcholine inhibitory effects.

In the context of the present invention, aqueous botulinum toxin formulations may include various other pharmaceutically acceptable substances, such as salts (e.g., sodium chloride), stabilizing proteins (e.g., albumin, gelatin), sugars (e.g., glucose, fructose, galactose, trehalose, sucrose, and maltose), carbohydrate polymers (e.g., hyaluronic acid and polyvinylpyrrolidone (PVP)), polyols (e.g., glycerol and sugar alcohols such as mannitol, inositol, lactitol, isomalt, xylitol, erythritol, sorbitol), amino acids, vitamins (e.g., vitamin C), zinc, magnesium, anesthetics (e.g., local anesthetics such as lidocaine), surfactants, tonicity modifiers, etc. As used herein, the term "pharmaceutically acceptable" refers to compounds or substances that are suitable for contact with the tissues of mammals, particularly humans.

Furthermore, as used herein, the term "comprising" is intended to encompass both the open-ended term "including" and the closed-ended term "consisting of." As used herein, the term "made of" is intended to broadly refer to "derived from," particularly "derived primarily from," and generally means "comprising," "including" (indicating that other substances or materials may be included in some amount). It may also mean "consisting of."

According to the present invention, the pH of the aqueous botulinum toxin formulation in the prefilled syringe during storage is preferably in the range of 6.0 to 7.5, 6.5 to 7.5, 6.1 to 7.3, or 6.2 to 7.2, more preferably in the range of 6.3 to 7.1, and most preferably in the range of 6.5 to 7.0. A pH in the indicated range of 6.1 to 7.3 is advantageous because injection of such a substantially neutral or only slightly acidic solution is much less painful than injection of an acidic solution having a pH below 6.

As used herein, the term "aqueous preparation" or "aqueous botulinum toxin preparation" is not particularly limited and may refer to an aqueous suspension, an aqueous dispersion, an aqueous emulsion, and preferably an aqueous solution.

Preferably, the aqueous botulinum toxin formulation does not contain a buffer, such as a phosphate buffer, a phosphate-citrate buffer, a lactate buffer, an acetate buffer, or the like. As used herein, the term "buffer" refers to a pharmaceutically acceptable excipient that stabilizes the pH of the pharmaceutical preparation. In addition, the aqueous botulinum toxin formulation may not contain amino acids (e.g., methionine) and/or surfactants (e.g., polysorbates, such as polysorbate 80) and/or animal-derived proteins (e.g., human serum albumin (HSA) or bovine serum albumin (BSA)).

Preferred aqueous botulinum toxin formulations for use herein comprise water, a concentration (e.g., 10 to 150 U/ml) of botulinum toxin (e.g., the neurotoxic component of botulinum toxin, preferably serotype A), a concentration (e.g., 0.5% to 1.5% w/v) of a salt (e.g., sodium chloride), a concentration (e.g., 0.1% to 2% w/v) of a sugar (e.g., a mono- or disaccharide such as glucose, fructose, galactose, trehalose, sucrose, and maltose), and a concentration (less than 4%, 3%, 2%, or 1% w/v, e.g., 0.01% to 1% w/v) of a stabilizing protein (e.g., albumin).

Particularly preferred aqueous botulinum toxin formulations for use herein consist essentially of water, botulinum toxin (e.g., the neurotoxic component of botulinum toxin type A), sodium fluoride, sucrose, and albumin (e.g., human serum albumin). The concentrations of the aforementioned ingredients may range from 10 to 200 U/ml, preferably 30 to 125 U/ml (botulinum toxin); 0.5% to 1.5% w/v, preferably 0.7% to 1.1% w/v (sodium chloride); 0.1% to 2% w/v, preferably 0.2% to 1% w/v (sucrose); and 0.01% to 1% w/v, preferably 0.05% to 0.5% w/v (HSA). Another particularly preferred botulinum toxin formulation for use herein is a solution, such as a solution reconstituted with normal saline (0.9% sodium chloride), containing 20 to 150 U/ml of the neurotoxic component of botulinum toxin type A.

As used herein, the term "consisting essentially of" is intended to mean that substances other than the specified substances are present only in trace amounts, such as unavoidable impurities contained in components used to formulate aqueous botulinum toxin formulations, and impurities contained in very low amounts in isolated botulinum toxin (e.g., the neurotoxic component of botulinum toxin type A) as a result of a purification process (e.g., very low residual amounts of buffers, chelating agents, etc.).

According to the present invention, the construction of the prefilled plastic syringe is not particularly limited and generally includes a fluid-receiving barrel that is removably capped after filling by a capping device (e.g., by removing or replacing a "tip cap" with a needle before use, or a sealing means such as a needle cover in the case of prefilled syringes with removable or permanent needles) to hermetically close the distal end of the syringe, and the fluid-receiving barrel is sealed at the proximal end by its plunger or any other means that fluid-tightly engages the inner wall of the barrel. To use the prefilled syringe, the tip cap, needle cover, or other type of capping device is removed, a needle is optionally attached (if not already present), and the plunger tip or piston is then advanced into the syringe barrel to inject the contents of the barrel (i.e., the aqueous botulinum toxin formulation) into the patient.

The pre-filled plastic syringe according to the present invention preferably comprises:

(a) a plastic syringe barrel comprising a proximal end and a distal end, and a generally cylindrical wall extending between the proximal and distal ends and defining a barrel lumen, the syringe barrel having a distally projecting tip, wherein a fluid passage extends through the tip and communicates with the barrel lumen, wherein the generally cylindrical wall has an inner surface optionally coated with a barrier layer,

(b) a closure having an outlet engagement portion that sealingly engages and closes the distal open outlet end of the syringe, wherein the outlet engagement portion is made of an elastomeric material optionally having a coating on a surface thereof, and

(c) a plunger rod assembly extending into the proximal end of the syringe barrel and including a plunger stop in sliding, fluid-tight engagement with a cylindrical wall of the syringe barrel lumen, wherein the plunger stop is made of an elastomeric material, the elastomeric material optionally having a coating on at least a portion of the plunger stop, the coating contacting the aqueous botulinum toxin formulation during storage and/or injection.

The material of the pre-filled syringe that could potentially interact with the aqueous botulinum toxin formulation in the pre-filled syringe is typically selected to minimize or limit the amount of extractables and leachables, as extractables/leachables could potentially contaminate the aqueous botulinum toxin formulation and destabilize the botulinum toxin, e.g., with respect to biological activity or potency.

As used herein, the terms "extractables" and "leachables" refer to chemical substances that can be released from the material components of the container or pre-filled plastic syringe and/or chemical substances that migrate from the syringe material into the aqueous botulinum toxin formulation under normal use or storage conditions. Methods for identifying extractables/leachables are known in the art and are based on recommended industry practices and International Conference on Harmonization (ICH) guidelines (see, e.g., FDA Guidance, Container Closure Systems for Packaging Human Drugs and Biologics). Exemplary methods include, e.g., liquid chromatography/mass spectrometry (LC/MS), gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma (ICP), and infrared (IR).

In the context of the present invention, the inner surface of the plastic syringe barrel may or may not be coated. However, it is typically coated with a barrier layer (hereinafter also referred to as a "lubricant layer") for lubrication purposes. The lubricant layer should not only provide a high degree of lubricity, allowing the plunger to slide easily through the barrel, but also be compatible with the aqueous botulinum toxin formulation and protect the shelf life of the aqueous botulinum toxin formulation. In the context of the present invention, the lubricant layer can be a silicone-free lubricant layer or a silicone lubricant layer.

Likewise, the inner surface of the plastic vessel portion of the vial, the inner surface of the plastic column of the carpule bottle, and the inner surface of the plastic ampoule can optionally be coated with a barrier layer, in particular, a silicone-free layer or a silicone layer. Therefore, all descriptions provided below regarding the silicone-free lubricant layer and the silicone lubricant layer of the plastic syringe are also applicable to the silicone layer and silicone-free layer of the plastic vial, plastic carpule bottle, and plastic ampoule, respectively.

Suitable silicone-free fluoropolymer lubricating layers can be made from the materials described below for the optional coatings of the closure (or more specifically the outlet joint) and the plunger stopper. Preferred silicone-free lubricating layers include fluoropolymer (fluorocarbon) layers, particularly ethylene tetrafluoroethylene (ETFE) layers and perfluoropolyether-based (PFPE-based) layers (e.g., )), and silica-based glass PECVD (plasma enhanced chemical vapor deposition) coatings.

Such fluoropolymer layers can be prepared as known in the art, for example by spraying a plastic syringe barrel with a perfluoropolyether oil so that the lubricant forms a thin layer on the inner surface of the syringe, and then exposing the inner cavity to a downstream inert gas (e.g., argon or helium) plasma. The plasma treatment causes the perfluoropolyether to crosslink, thereby fixing the coating and reducing its tendency to migrate off the target surface, resulting in a reduction in particles that potentially compromise the stability/efficacy of the botulinum toxin drug. An exemplary preparation process is described in WO 2014/014641 A1, the contents of which are incorporated herein by reference. In addition, a particularly suitable silicone-free barrier coating for use herein is known in the art as a coating that is a perfluoropolyether coating crosslinked by a plasma treatment.

Suitable organosilicon lubricant layers useful herein can be prepared by a siliconization method selected from, but not limited to, silicone oil-based methods (e.g., spray siliconization or bake siliconization) and vapor deposition methods (e.g., plasma-enhanced chemical vapor deposition (PECVD)). Preferably, the organosilicon lubricant layer is formed by a spray siliconization method, or more preferably, by a bake siliconization method.

In the spray siliconization method, silicone oil (e.g., DOW360 with a viscosity of 1000 cSt) is sprayed into a syringe (i.e., a barrel) using, for example, a submersible nozzle or a static nozzle to produce a thin layer of silicone oil. Although silicone oil is an excellent lubricant, too much silicone oil can lead to the formation of unwanted visually visible and microscopic silicone oil particles. Especially when using protein-based drugs, these silicone oil particles can cause adverse interactions with protein drugs. For example, silicone oil particles that are only visible under a microscope are believed to promote protein aggregation. Therefore, since the baking siliconization method produces fewer microscopically visible and visually visible silicone oil particles, it is particularly preferred for use herein. This involves applying the silicone oil as an emulsion (e.g., DOW365 siliconizing emulsion) and then baking it on the plastic surface at a specific temperature for a specific time.

The design of the plastic syringe barrel is not particularly limited, and it typically has an internal diameter adjusted to accommodate the desired fill volume (e.g., 0.5 cm ³ , 1.0 cm ³ , 1.5 cm ³ or 2.0 cm ³ ). Typically, the syringe barrel has graduated markings indicating the volume of fluid in the syringe. In addition, the syringe barrel may include a flanged interface. The design of the flange may, for example, comply with ISO 11040. The flanged interface may further be compatible with an optionally present handle.

The syringe tip is typically formed integrally with the syringe plastic barrel (e.g., molded). Preferably, the syringe barrel comprises an integrally formed screw tip or an integrally formed straight tip. The formed tip has an integral passage extending axially through the tip and is communicated with the chamber for distributing the contents of the syringe barrel. The tip may have a substantially truncated cone shape that converges from the distal outlet end of the syringe barrel toward the outlet end of the tip. Alternatively, the features of the tip may diverge (i.e., expand from a smaller diameter to a larger diameter). In addition, the tip is typically located in the center relative to the syringe body (concentric syringe tip), but may also be located in an offset position toward the edge of the body (eccentric syringe tip).

Regarding the material of the syringe plastic barrel, the plastic material is preferably cycloolefin polymer (COP), cycloolefin copolymer (COC) or a mixture thereof. COC is produced by the polymerization of cyclic monomers (such as norbornene) and ethane, while COP is produced by ring-opening metathesis polymerization of cyclic monomers and then hydrogenation. COC, COC and COP/COC materials have many desired properties, including high transparency, low density, excellent moisture resistance and resistance to water and polar organic media. Specific examples include COC and Daikyo Crystal

Plastic vials, carpules and ampoules can be made of the plastic materials mentioned above for plastic syringe barrels, polyethylene (PP, such as HDPE, LDPE), polyester, polyethylene terephthalate (PET), polyamide and mixtures thereof. It is also conceivable that the plastic vials, carpules and ampoules have a multilayer structure, with the upper layer being made of one of the materials mentioned above and the other layers being made of one (or more) other materials.

According to the present invention, a "capping device" broadly refers to any means for closing and sealing the distal open outlet end of a syringe. As used herein, the terms "open outlet end" or "distal open outlet end" refer to any distal open end of a syringe that is in fluid communication with the lumen of the syringe barrel. The capping device typically has a passageway with a closed end and an open end and is sized to receive and effectively seal the open outlet end of a syringe to prevent leakage.

In the case of pre-filled plastic syringes without pre-installed needles, the capping device is a capping tool generally referred to as a "tip cap". The tip cap forms a fluid seal with the tip of the syringe to effectively seal the syringe barrel and prevent the contents of the syringe barrel from leaking. The tip cap is generally removably connected to the syringe tip or Luer collar. The Luer collar surrounds the top of the syringe barrel (e.g., syringe tip). Preferably, the Luer collar has an internal thread, and the tip cap has an external thread complementary to the internal thread of the Luer collar for connecting the tip cap to the syringe barrel. In the case of the pre-filled plastic syringe of the present invention, the Luer collar is generally formed as a whole with the syringe barrel (e.g., integrally molded). Before use, the tip can be removed and the needle cannula (needle assembly) can then be securely connected to the syringe tip.

If a pre-filled plastic syringe includes a removable or non-removable (permanent) cannula or needle cannula (also referred to as a "needle" or "needle assembly") extending from the syringe tip for delivering an aqueous botulinum toxin formulation from the syringe, the capping device may be referred to as a "needle cover." The needle cover typically has a passageway with a closed end and an open end that is sized to receive and couple with a cannula (needle) mounted on the syringe tip. Typically, the (sharp) end of the cannula passes through the closed end of the passageway in the needle cover to seal against the open end of the cannula.

The capping device (e.g., a tip cap or needle cover) can be a unitary component and is typically made of a flexible and resilient polymeric material (e.g., an elastomer), or can have an outer cap made of a rigid plastic material that is coupled to a flexible and resilient inner cap or material comprising or made of, for example, an elastomer, at least a portion of which contacts and seals the distal opening of the syringe. Typically, at least the outlet joint that contacts the distal tip opening to form a fluid-tight seal is made of a flexible and/or resilient material (e.g., an elastomer), and because this joint contacts the aqueous botulinum toxin formulation during storage and/or use, it is preferably made of a material that is least likely to form undesirable extractables/leachables. To further reduce the amount of extractables and/or leachables and increase compatibility with aqueous botulinum toxin formulations, the outlet joint can have a coating thereon.

Suitable flexible and/or resilient materials for the closure device (particularly the outlet joint) include elastomers that do not interfere with the aqueous botulinum toxin formulation and are capable of long-term storage. Specifically, during long-term storage of the aqueous botulinum toxin formulation, the portion of the closure device that contacts or is configured to contact the aqueous botulinum toxin formulation (i.e., the outlet joint) should have low levels of extractables/leachables. As used herein, the terms "elastomer" or "elastomeric material" primarily refer to cross-linked thermosetting rubber polymers that are more easily deformed than plastics but are approved for use with pharmaceutical-grade fluids and are not susceptible to leaching or gas migration.

Preferably, the elastomeric material suitable for use herein is selected from isoprene rubber (IS), butadiene rubber (polybutadiene, BR), butyl rubber (copolymer of isobutylene and isoprene; IIR), halogenated butyl rubber (e.g., chlorobutyl rubber, CIIR; and bromobutyl rubber: BIIR), styrene-butadiene rubber (copolymer of styrene and butadiene, SBR), and mixtures thereof. Preferably, the elastomeric material is butyl rubber or halogenated butyl rubber (particularly bromobutyl rubber or fluorobutyl rubber), or a mixture thereof. Inert minerals may also be used to reinforce the elastomeric material. In addition, the elastomeric material may be cured (e.g., using organic peroxides, phenolic resins, etc.).

Suitable coatings that may optionally be present on the outlet joint made of, for example, the above-mentioned elastomeric materials are generally made of materials that do not undesirably interfere with aqueous botulinum toxin formulations and exhibit low extractable/leachable levels. Coatings useful herein include, but are not limited to, polypropylene, polyethylene, parylene (e.g., N-type parylene, C-type parylene, and HT-type parylene), cross-linked silicones, and preferably fluoropolymer coatings. Examples of suitable cross-linked silicone coatings include B2-coat (Daikyo Seiko) or XSi ^™ (Becton Dickinson).

Fluoropolymer coatings include, but are not limited to, fluorinated ethylene-propylene copolymers (e.g., tetrafluoroethylene-hexafluoropropylene copolymers (FEP)), fluorinated ethylene-ethylene copolymers (e.g., ethylene-tetrafluoroethylene copolymers (ETFE), such as), PVA (a copolymer of tetrafluoroethylene (TFE) and perfluoropropyl vinyl ether (PPVE)), tetrafluoroethylene-perfluoroethylene copolymers, polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polytetrafluoroethylene (PTFE), and mixtures thereof. Preferably, the coating is made of ETFE, and in particular is a coating.

In the case of the carpule bottle of the present invention, its distal end is sealed by a piercing membrane. The piercing membrane can be formed from thin rubber or silicone, thin plastic/polymer, film (such as Mylar), polyolefin (such as polyethylene or polypropylene), metal foil (such as aluminum foil), etc. The thickness of the membrane can be between about 0.001 mm and 2.0 mm, typically between 0.002 mm and 0.65 mm. Alternatively, the membrane can be made of an elastomeric material and optionally have a coating as described above in conjunction with the capping device for the prefilled plastic syringe.

With regard to the vials of the present invention, the vial closure system (e.g., the cap), in particular those parts of the vial closure system that come into contact with or may come into contact with the vial and/or seal the vial (e.g., the septum), can be made of an elastomeric material, in particular a thermoplastic elastomeric material, more particularly a styrene block copolymer thermoplastic elastomer, or an elastomeric material as described above in conjunction with the closure device for the prefilled plastic syringe of the present invention. Another suitable material is a silicone material. Furthermore, the material can have an optional coating, in particular a fluoropolymer coating, as defined above with respect to the closure device for the prefilled plastic syringe.

According to the present invention, the prefilled syringe generally includes a plunger rod assembly that extends into the proximal end of the syringe barrel. The plunger rod assembly may include a rod (also referred to as a push rod) having a plunger stop (also referred to as a "plunger") at the tip of the rod that is in sliding, fluid-tight engagement with the cylindrical wall of the syringe barrel lumen. The plunger forms a proximal seal and a dynamic seal that allows extrusion of the liquid botulinum toxin formulation. During storage and/or administration, the plunger stop contacts the aqueous botulinum toxin formulation. Therefore, the plunger stop should be compatible with the aqueous botulinum toxin formulation and not compromise its long-term stability. Specifically, the plunger stop should preferably be designed to minimize the amount of extractables/leachables during prolonged storage.

In the present invention, the plunger stop is preferably made of an elastomeric material, optionally having a coating on at least a portion of the plunger stop that contacts or is capable of contacting the aqueous botulinum toxin formulation during storage and/or use. Suitable plunger stop elastomeric materials that can be used herein include, but are not limited to, isoprene rubber (IS), butadiene rubber (polybutadiene, BR), butyl rubber (copolymer of isobutylene and isoprene, IIR), halogenated butyl rubber (e.g., fluorobutyl rubber, CIIR; and bromobutyl rubber, BIIR), styrene-butadiene rubber (copolymer of styrene and butadiene, SBR), and mixtures thereof. Preferably, the plunger stop material is butyl rubber or halogenated butyl rubber or a mixture thereof, particularly bromobutyl rubber or fluorobutyl rubber. Inert minerals can also be used to reinforce the elastomeric material. In addition, the elastomeric material can be cured (e.g., using organic peroxides, phenolic resins, etc.).

Preferably, the plunger stop includes a coating that acts as a barrier film. The coating is typically applied to at least the sealing surface, including the portion of the plunger stop that faces the barrel lumen and contacts the aqueous botulinum toxin formulation during storage and/or use. The purpose of the coating is to provide good lubricity while minimizing interaction between the plunger stop and the liquid botulinum toxin formulation.

Suitable coatings for the plunger stop are generally made of materials that do not undesirably interfere with aqueous botulinum toxin formulations and have low levels of extractables/leachables. Such coatings include, but are not limited to, polypropylene, polyethylene, parylene (e.g., N-type parylene, C-type parylene, and HT-type parylene), cross-linked silicones, and preferably fluoropolymer coatings. Examples of suitable cross-linked silicone coatings include B2-coat (Daikyo Seiko) or XSi ^™ (Becton Dickinson).

Fluoropolymer coatings include, but are not limited to, fluorinated ethylene-propylene copolymers (e.g., tetrafluoroethylene-hexafluoropropylene copolymers (FEP)), fluorinated ethylene-ethylene copolymers (e.g., ethylene-tetrafluoroethylene copolymers (ETFE), such as), PVA (a copolymer of tetrafluoroethylene (TFE) and perfluoropropyl vinyl ether (PPVE)), tetrafluoroethylene-perfluoroethylene copolymers, polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polytetrafluoroethylene (PTFE), and mixtures thereof. Preferably, the coating is made of ETFE, and is specifically a coating.

The design of the plunger stop is not particularly limited and can be a nested or pocketed stop. In addition, the interface that engages the rod can be threaded to allow the rod to be installed after sterilization. Alternatively, the interface that engages the rod can be designed using a snap-on design. Rods, such as plunger stops, are generally designed to withstand sterilization but are not otherwise limited in any particular way. Typically, the rod is made of a plastic material, such as ethylene vinyl acetate (EVA) copolymer or polypropylene.

The rubber stopper of the carple bottle of the present invention can comprise or be made of the same elastomeric material as described above in conjunction with the plunger stopper of the plastic syringe. Additionally, the rubber stopper of the carple bottle can have the same optional coating as defined above for the coating on the plunger stopper. Furthermore, the coating can be located on at least a portion of the rubber stopper that comes into contact with the aqueous botulinum toxin formulation during storage and/or use.

Within the framework of the present invention, the prefilled plastic syringe comprising the closure device, syringe barrel and plunger assembly meets or exceeds the standards for extractable substances as determined by the Japanese Pharmacopoeia 14th Edition, No. 61, "Test Methods for Plastic Containers (2001)" and the standards of the Japanese Pharmacopoeia 14th Edition, No. 59, "Tests for Rubber Closures for Aqueous Infusions" before and after sterilization (e.g., by gamma irradiation, ethylene oxide, or autoclaving). In addition, after sterilization, the polymer composition of the closure device and plunger stopper meets the Japanese Pharmacopoeia 61, "Test Methods for Plastic Containers (2001)" flame test, as well as the acceptable limits for extractable substances as defined by the Japanese Pharmacopoeia 61, "Test Methods for Plastic Containers (2001)" foaming test, pH test, potassium permanganate reducing substance test, UV spectroscopy test, and evaporation residue test.

In another aspect, the present invention relates to a kit comprising a prefilled plastic container (eg, a syringe, a vial, a carpule, or an ampoule) according to the present invention and optionally instructions for use of the prefilled plastic container.

In another aspect, the present invention relates to a prefilled plastic container (e.g., a syringe, vial, carpule, or ampoule) for use in therapy according to the present invention. In particular, the prefilled plastic container according to the present invention can be used to treat a disease or condition caused by or associated with overactive cholinergic innervation of a patient's muscles or exocrine glands.

In the context of the present invention, if the container is not a syringe (e.g., a vial, carpule, or ampoule), the contents of these "non-syringe type" containers (i.e., aqueous botulinum toxin formulations) are typically injected into the desired target site using a suitable injection device (e.g., a syringe) in the same manner as described herein for pre-filled plastic syringes. As known to those skilled in the art, the carpule is inserted into the carpule injection device. The contents of the vial and ampoule are typically aseptically filled into a syringe and then injected into the target site using a suitable injection device (e.g., a syringe) in the same manner as described herein for pre-filled plastic syringes.

As used herein, the term "cholinergic hyperactivity" refers to a synapse characterized by abnormally high amounts of acetylcholine released into the synaptic cleft. "Abnormally high" refers to an increase, for example, of up to 25%, up to 50%, or more, relative to a reference activity, which can be determined, for example, by comparing the release to that at synapses of the same type that are not in a hyperactive state, where muscle dystonia can indicate a hyperactive state. "Up to 25%" refers, for example, to about 1% to about 25%. Methods for making the desired measurements are known in the art.

In the present invention, diseases or conditions caused by or associated with overactive cholinergic innervation of muscles include, but are not limited to, dystonia (e.g., blepharospasm, spasmodic torticollis, limb dystonia, and task-specific dystonia (such as writer's cramp)), spasticity (e.g., post-stroke spasticity, spasticity caused by cerebral palsy), hyperextension, movement disorders (e.g., tardive dyskinesia), hemifacial spasm (e.g., hemifacial spasm), (juvenile) cerebral palsy (e.g., spastic cerebral palsy, dyskinetic cerebral palsy, or ataxic cerebral palsy), strabismus, pain (e.g., neuropathic pain), wound healing, tremors, convulsions, and migraines.

The prefilled botulinum toxin containers (e.g., syringes, vials, carpules, or ampoules) of the present invention are particularly useful for treating muscle dystonia. Exemplary dystonias include, but are not limited to, dystonias selected from the following types: (1) craniofacial dystonias, including blepharospasm and oromandibular dystonia of the open or closed mouth type, (2) cervical dystonias, including flexion of the neck, retroversion of the neck, lateral tilt of the neck, and torticollis, (3) pharyngeal dystonias, (4) laryngeal dystonias, including spasmodic dystonias, (5) limb dystonias, including arm dystonias such as task-specific dystonias (e.g., writer's cramp), leg dystonias, axial dystonias, segmental dystonias, and (6) other dystonias.

As used herein, the term "overactive exocrine gland" is not particularly limited and encompasses any overactive exocrine gland. Thus, it is contemplated that the present invention may be applied to treatments involving any of the glands described in Sobotta, Johannes, Atlas der Anatomie des Menschen, 22. Auflage, Bands 1 and 2, Urban & Fischer, 2005 (Sobotta, Johannes, Atlas der Anatomie des Menschen, 22nd ed., Vols. 1 and 2, Urban & Fischer, 2005), which is incorporated herein by reference. Preferably, the overactive gland is an autonomous exocrine gland. Preferably, the botulinum toxin composition is injected into or near the overactive exocrine gland.

In the present invention, overactive exocrine glands include, but are not limited to, sweat glands, tear glands, salivary glands, and mucosal glands. Additionally, overactive glands may be selected from or associated with a disease or condition of the following types: Frey's syndrome, crocodile tears syndrome, axillary hyperhidrosis, palmar hyperhidrosis, plantar hyperhidrosis, head and neck hyperhidrosis, body hyperhidrosis, rhinorrhea, or relative hypersalivation in patients with stroke, Parkinson's disease, or amyotrophic lateral sclerosis. Specifically, diseases or conditions caused by or associated with overactive cholinergic innervation may include drooling (excessive salivation, sialorrhea) and excessive sweating (hyperhidrosis).

Administration is not limited to any particular administration regimen, mode, form, dosage, and interval. As known to those skilled in the art, the amount or dosage of botulinum toxin administered depends on the mode of application, the type of disease, the patient's weight, age, sex, and health status, and the target tissue selected for injection. Botulinum toxin formulations are typically administered topically, for example, by subcutaneous or intramuscular injection into or near the target tissue (e.g., muscle, skin, exocrine glands).

Different muscles (depending on their size) generally require different dosages. A suitable dosage may be in the range of 10U to 2000U, preferably 50U to 500U, more preferably 100U to 350U of botulinum toxin. For the treatment of exocrine glands, the dosage is generally in the range of 10U to 500U, preferably 20U to 200U, and more preferably 30U to 100U. Such a total amount may be administered on the same day of treatment or on a subsequent day. For example, during the first treatment period, the first portion of the dosage may be administered. During one or more treatment periods, the remainder of the total dosage may be administered. In addition, there is no specific limit to the frequency of application, and a suitable administration interval may be 3 months or less (e.g., 4 to 8 weeks) or more than 3 months.

In another aspect, the present invention relates to the use of a prefilled plastic container (e.g., a syringe, vial, carpule, or ampoule) according to the present invention in cosmetic applications, such as for treating facial asymmetry and wrinkles/lines of the skin (e.g., facial lines and facial wrinkles), including upper facial wrinkles, platysma bands, glabellar frown lines, horizontal forehead lines, nasolabial folds, chin folds, double chin, mental cleft, marionette lines, buccal commissures, perioral wrinkles, crow's feet, and jawline. Preferably, the prefilled botulinum toxin container (e.g., a syringe, vial, carpule, or ampoule) of the present invention is for injection into glabellar frown lines, crow's feet, perioral wrinkles, and/or platysma bands.

The amount of botulinum toxin administered for cosmetic applications is typically in the range of 1 U to 5 U, 5 U to 10 U, 10 U to 20 U, or 20 U to 50 U. Such total amount can be administered on the same day of treatment or on a subsequent day. For example, during the first treatment session, a first portion of the dose can be administered. This first portion is preferably a suboptimal portion, i.e., a portion that does not completely remove wrinkles or fine lines. The remainder of the total dose can be administered during one or more treatment sessions. For further details on administration, reference is made to the disclosure regarding therapeutic uses provided above.

In yet another aspect, the present invention is directed to a method of treating a disease or condition caused by or associated with overactive cholinergic innervation of a patient's muscles or exocrine glands, the method comprising topically administering an effective amount of a botulinum toxin to the patient's muscles or exocrine glands using a prefilled plastic container (e.g., a syringe, vial, carpule, or ampoule) according to the present invention.

As used herein, the term "effective amount" refers to an amount of botulinum toxin sufficient to achieve a beneficial or desired therapeutic, cosmetic, or anesthetic result. As used herein, the term "patient" generally refers to a person suffering from a disease or condition caused by or associated with overactive cholinergic innervation of muscles or exocrine glands, or to a person in need of cosmetic or anesthetic treatment. As used herein, "patient" is used interchangeably with "subject" or "individual."

Within the meaning of the present invention, the term "topical administration" preferably refers to subcutaneous injection or intramuscular injection into or near the target tissue (e.g., muscle, skin, exocrine glands). With regard to administration (e.g., regimen, mode, form, dosage, and interval) and the disease or condition to be treated, the same instructions as those described above for glass containers for cosmetic and therapeutic applications (e.g., pre-filled botulinum toxin syringes) apply.

In yet another aspect, the present invention relates to a method for cosmetic treatment of the skin, such as for treating skin wrinkles and facial asymmetry, comprising topically administering to a patient an effective amount of botulinum toxin by intradermal, subdermal, or subcutaneous injection using a prefilled plastic container (e.g., a syringe, vial, carpule, or ampoule) according to the present invention.

Exemplary cosmetic applications include those mentioned above. With respect to the meaning or definitions of the terms "effective amount," "patient," "administration (e.g., regimen, mode, form, dosage, and interval)," and "disease or condition to be treated," the descriptions provided above regarding other aspects of the invention apply equally, unless otherwise indicated.

The invention will now be further illustrated by the following non-limiting examples.

Example

The following examples demonstrate that, contrary to expectations and prevailing belief in the art, aqueous botulinum toxin formulations stored in prefilled syringe systems exhibit excellent stability over long periods (e.g., 9-12 months) at standard refrigerated temperatures (2-8°C). Furthermore, extrapolation of the measured stability data indicates that prefilled botulinum toxin syringes are highly stable for at least 12 to 24 months at 2-8°C.

Therefore, the botulinum toxin can be changed from a lyophilized vial to a pre-filled plastic syringe, which meets the needs of physicians and patients for easier discovery and a safer and more accurate mode of administration.

Materials and methods

An aqueous botulinum toxin formulation was prepared by dissolving 1.0 mg of human serum albumin (HSA), 4.7 mg of sucrose, and incobotulinum toxin A in 0.9% saline to a concentration of 50 U/ml. This formulation was then loaded into a plastic syringe barrel with a screw-type closure comprising a screw thread and a tip cap that, upon assembly, contacts the distal syringe tip opening to seal the syringe barrel. A plunger stopper was then inserted into the proximal end portion of the syringe barrel to close the proximal opening. The resulting prefilled plastic syringes were then stored at either 5°C or 25°C. The stability of the aqueous botulinum toxin formulation was then evaluated at t = 0, 1, 3, 6, 9, and 12 months by measuring residual toxin potency, pH, and microscopic particle counts.

Toxin potency was determined using the mouse hemidiaphragm assay (HDA) according to [Et al., Exp. Neurol. 147: 96-102, 1997]. Briefly, the assay was performed by keeping a mouse neuromuscular preparation in an organ bath containing 4 ml of culture medium. The muscle was attached to a force transducer and electrically stimulated via the phrenic nerve, resulting in isometric contraction forces that remained constant for more than 180 minutes without the addition of toxin. After the toxin was introduced into the organ bath, the contraction amplitude of the nerve-stimulated muscle gradually decreased. The contraction amplitude of the diaphragm was monitored over time. As a readout, the time to reach half of the initial contraction force was determined and referred to as the paralysis time. An increase in the time value compared to the initial value reflected a lower amount of active toxin and a loss of toxin potency, respectively.

The pH was measured using a pH meter (Lab 870, Schott Instruments) according to United States Pharmacopeia Standard Test Method USP <791>, which outlines pH measurements for many drug products.

Particles were measured using microfluidics imaging (MFI) using a DPA-5200 particle analyzer system (ProteinSimple, Santa Clara, CA, USA) equipped with a silane-coated high-resolution 100 μm flow cell. Samples were analyzed without dilution. MFI View System Software (MVSS) version 2-R2-6.1.20.1915 was used to perform the measurements, and MFI View Analysis Suite (MVAS) software version 1.3.0.1007 was used to analyze the samples.

Two different pre-filled plastic syringe systems (hereinafter "Configurations A and B") were investigated, which differed from each other in the plunger stop. Details of the syringe configurations tested are summarized in Table 1.

Table 1. Syringe Configurations A and B

1 = Gerresheimer

2 = Siliconized with Dow Medical Fluid 360 (viscosity 12,500 cSt)

3 = Sterilized by gamma irradiation according to ISO 11137

result

The results of stability measurements in terms of residual toxin potency for Constructions A and B are shown in Table 2 below.

Table 2. Stability in terms of potency

*Initial absolute toxin activity units range from 50U to 54U

**n.d.=not determined

As is apparent from Table 2, the toxin substantially maintains its initial potency over time at 2-8°C, i.e., there is substantially no potency loss after storage for no less than 18 months (potency loss after 18 months of storage <10%). Even at room temperature (i.e., 25°C), stability is still acceptable, as indicated by a potency loss of no more than about 20% after 3 months.

The stability data for constructs A and B stored at 2-8°C for up to 24 months were extrapolated and the results are shown graphically in Figure 1. As can be seen from the figure, the estimated maximum loss of bioactivity after 24 months is expected to be approximately 10%, which is essentially the same as the loss of bioactivity measured after 12 months.

Furthermore, pH measurements showed that the pH remained very stable over a period of up to 18 months. No trends towards higher or lower values were observed, and all measured pH values remained within ±0.4 of the initial pH (see Table 3).

Table 3. pH stability

Furthermore, particle size measurements by microfluidic imaging indicated that the overall number of particles was low and that there was no significant increase in the number of particles (see Table 4).

Table 4. Stability of microscopic particle counts

As can be seen from Table 4, the particle counts remained well below 1000/ml and in most cases even below 250/ml. Likewise, particle measurements performed by means of the resonant mass measurement (RMM) method (using an ARCHIMEDES particle method system; Affinity Biosensors, Santa Barbara, CA, USA) and nanoparticle tracking analysis (using a NanoSight LM20 system; NanoSight, Amesbury, UK) yielded similar results and showed no significant particle counts.

In summary, the results presented above demonstrate that liquid botulinum toxin formulations in pre-filled plastic syringes are stable after long-term storage (e.g., 12-24 months) at temperatures between 2 and 8°C. This finding is highly surprising given the labile nature of botulinum toxin, which is known to be highly thermally unstable and unstable at alkaline pH. This is even more surprising because the concentration of botulinum toxin in the pre-filled syringes is very low, so even minimal absolute loss of active toxin can result in a large percentage change.

Thus, the above results indicate that botulinum toxin can be formulated in a prefilled plastic syringe format, which offers advantages over glass syringes in terms of resistance to breakage, reduced weight, increased flexibility for the novel shape of the initial container, improved dimensional tolerances, and the absence of undesirable substances (e.g., adhesives). Furthermore, compared to other botulinum toxin presentation forms, the prefilled syringe format increases convenience and ease of handling, reduces medication errors, improves dosing accuracy, minimizes contamination risk, improves sterility assurance, and increases administration safety.

Claims (12)

1. A pre-filled plastic syringe comprising an aqueous botulinum toxin preparation with a pH in the range of 6.1 to 7.3, said plastic syringe comprising: (a) A plastic syringe barrel including a proximal end and a distal end, and a generally cylindrical wall extending between the proximal end and the distal end and defining a barrel cavity, the syringe barrel having a distally projecting tip, wherein a fluid channel extends through the tip and communicates with the barrel cavity, wherein the generally cylindrical wall has an inner surface coated with a barrier layer. (b) A capping device having an outlet engagement that sealably engages and closes the distal opening outlet end of the syringe, wherein the outlet engagement is made of an elastomeric material having or not having a coating on its surface, and (c) A plunger rod assembly extending into the proximal end of the syringe barrel and including a plunger stop that is in a sliding fluid-sealed engagement with the generally cylindrical wall of the barrel cavity, wherein the plunger stop is made of an elastomeric material having a coating on at least a portion of the plunger stop, the coating of the plunger stop contacting the aqueous botulinum toxin formulation during storage and/or injection. The elastomer material of the outlet joint is selected from isoprene rubber (IS), butadiene rubber (BR), butyl rubber, halogenated butyl rubber, styrene-butadiene rubber, and mixtures thereof. The elastomeric material of the plunger stop is selected from isoprene rubber (IS), butadiene rubber (BR), butyl rubber, halogenated butyl rubber, styrene-butadiene rubber, and mixtures thereof. The barrier layer is a silicone layer, and the coating on the plunger stop is a cross-linked silicone coating or a fluoropolymer coating. When the pre-filled plastic syringe is stored at 5°C for 12 months or at 25°C for 3 months, the toxin activity decreases by no more than 25% relative to the initial toxin activity. 2. The pre-filled plastic syringe according to claim 1, wherein during storage at 2°C to 25°C for 6 to 24 months, the number of microscopically visible particles of 10 μm or larger is less than 1000/ml. 3. The prefilled plastic syringe according to claim 1, wherein during storage of the prefilled plastic syringe at 2°C to 25°C for 6 to 24 months, the pH value increases or decreases by no more than 10% relative to the initial pH value, or wherein during storage, the pH of the aqueous botulinum toxin preparation is maintained in the range of 6.1 to 7.3, or both of the above. 4. The prefilled plastic syringe of claim 2, wherein during storage of the prefilled plastic syringe at 2°C to 25°C for 6 to 24 months, the pH value increases or decreases by no more than 10% relative to the initial pH value, or wherein during storage, the pH of the aqueous botulinum toxin preparation is maintained in the range of 6.1 to 7.3, or both of the above. 5. The pre-filled plastic syringe according to any one of claims 1 to 4, wherein botulinum toxin is present in the aqueous botulinum toxin preparation at a concentration of 10 U/mL to 1000 U/mL. 6. The prefilled plastic syringe according to any one of claims 1 to 4, wherein the aqueous botulinum toxin preparation in the prefilled plastic syringe does not contain a buffer. 7. The pre-filled plastic syringe according to claim 5, wherein the aqueous botulinum toxin preparation in the pre-filled plastic syringe does not contain a buffer. 8. The prefilled plastic syringe according to any one of claims 1 to 4, wherein the coating of the outlet junction is a cross-linked silicone coating or a fluoropolymer coating. 9. The pre-filled plastic syringe according to claim 5, wherein the coating of the outlet junction is a cross-linked silicone coating or a fluoropolymer coating. 10. The pre-filled plastic syringe according to claim 6, wherein the coating of the outlet junction is a cross-linked silicone coating or a fluoropolymer coating. 11. The pre-filled plastic syringe according to claim 7, wherein the coating of the outlet junction is a cross-linked silicone coating or a fluoropolymer coating. 12. A kit comprising a pre-filled plastic syringe according to any one of claims 1 to 11, the kit including or excluding instructions for use of the pre-filled plastic syringe.