Sustained release injectable formulations using aprotic polar solvents

Abstract

The present invention relates to the use of aprotic polar solvents, water, and ionization stabilizers to prepare stable therapeutic formulations, particularly sustained-release formulations, of various active pharmaceutical ingredients (APIs), such as levothyroxine. In particular, the present invention relates to the use of aprotic polar solvents and at least one ionization stabilizer to prepare stable therapeutic formulations of various APIs by dissolving at least one API in an aprotic polar solvent system to produce stable sustained-release therapeutic formulations useful for the treatment, prevention, and / or diagnosis of diseases or disorders in humans and veterinary animals. The present invention also provides methods for producing such formulations.

Description

[Technical Field]

[0001] CROSS-REFERENCE AND INCORPORATION-BY-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 63 / 380,213, filed October 19, 2022, which is incorporated herein by reference in its entirety.

[0002] A. Field of the Invention The present invention relates to the fields of medicine and pharmacy. Certain aspects generally relate to therapeutic aprotic solvent formulations containing one or more active pharmaceutical ingredients that can be used as therapeutic formulations, particularly sustained-release formulations, in treating, preventing, and / or diagnosing diseases, disorders, and medical conditions in mammals, particularly humans. In particular, the present invention relates to the use of aprotic polar solvents and at least one ionization stabilizer to prepare stable therapeutic formulations of various active pharmaceutical ingredients (APIs) by dissolving at least one API in an aprotic polar solvent system to produce stable sustained-release therapeutic formulations useful for treating, preventing, and / or diagnosing diseases or disorders in humans and veterinary animals. [Background technology]

[0003] B. Description of Related Art Parenteral formulations of therapeutic molecules (e.g., active pharmaceutical ingredients, such as therapeutic peptides, proteins, and small molecules) prepared in aprotic polar solvent systems (e.g., DMSO-based solvent systems) offer the advantage of improved stability of the drug molecules due to the absence of water-mediated degradation pathways. These pathways, including hydrolysis, deamidation, and aspartic acid isomerization, are known to be significant contributors to the instability of peptides and proteins in aqueous-based formulations. Furthermore, hydrolysis is known to promote the chemical instability of small molecule drugs. Previous studies have demonstrated that low-water peptide and small molecule formulations in DMSO have improved stability compared to aqueous solutions (see, e.g., U.S. Patent Nos. 9,339,545, 10,485,850, and 11,020,403; the disclosures of all of which are incorporated herein in their entireties).

[0004] However, one drawback of such formulations is that they do not necessarily promote sustained-release pharmacokinetics in subjects administered such formulations to treat, prevent, or diagnose a disease or physical disorder without the need for the addition of a specific release modifier. Sustained-release formulations in which the drug precipitates at the injection site are known in the art. These formulations typically contain a release modifier that causes drug precipitation or co-precipitation of the drug and the release modifier to form a depot at the injection site. One example is the formulation of a specific polymer (e.g., PLGA) and drug in DMSO (see, e.g., US 2021 / 0401945 A1; the disclosure of which is incorporated herein in its entirety). Upon injection, PLGA, which is insoluble in aqueous / physiological media, encapsulates the soluble drug. Diffusion of the therapeutic compound from the PLGA matrix into the surrounding tissues and the patient's bloodstream results in sustained-release pharmacokinetics of the administered drug. Thus, to date, the development of sustained-release formulations of therapeutic compounds in non-aqueous liquid systems has primarily focused on adding specific such release modifiers to drug formulations to create a sustained-release effect. These release modifiers can be polymer molecules, particles, liposomes, etc. However, the use of release modifiers can be expensive, thereby increasing the cost of therapeutic formulations to manufacturers, distributors, healthcare providers, and patients, and to the healthcare system as a whole. The use of release modifiers can also often lead to the need to administer large injection volumes, which can cause discomfort or pain to patients, introduce stability issues, or cause toxic or allergenic effects to patients receiving formulations containing the release modifiers.

[0005] Thus, there is a need in the art for stable, ready-to-use sustained-release therapeutic formulations that overcome the problems associated with previously available sustained-release formulations of therapeutic agents. Such formulations would not only be shelf-stable but would also allow for weekly (or less frequent) self-administration of therapeutic formulations by patients in outpatient settings for the treatment of a variety of physical disorders and diseases typically treated with daily (or more frequent) administration. Such formulations would offer several advantages over currently available formulations, including avoiding absorption issues present with currently used oral formulations of certain therapeutic agents (including oral sustained-release formulations) by injecting the formulation in a manner that bypasses the gastrointestinal tract (e.g., subcutaneously) and potentially improving patient experience and compliance compared to daily oral dosing regimens or injections of sustained-release formulations containing release modifiers. Furthermore, such formulations could provide improved solubility for therapeutic agents that are typically poorly soluble or insoluble in typical aqueous solvent systems and longer shelf-life stability of the resulting formulations, potentially improving the economics of these therapeutic formulations compared to other commercial products. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 9,339,545 [Patent Document 2] U.S. Patent No. 10,485,850 [Patent Document 3] U.S. Patent No. 11,020,403 [Patent Document 4] US 2021 / 0401945 A1 Summary of the Invention

[0007] Brief Summary of the Invention The embodiments described herein provide formulations containing various pharmaceutical ingredients that meet the above-mentioned needs in the art. In further embodiments, the present invention also provides methods for producing such formulations, particularly sustained-release formulations, and methods for using the formulations in treating, preventing, and / or diagnosing various diseases, disorders, and conditions in humans and veterinary animals. A significant advantage of certain embodiments of the present invention is that release modifiers do not need to be included in the injectable formulation to create a sustained-release formulation of a therapeutic agent. Therefore, such formulations are inherently simple to manufacture, resulting in economic benefits for manufacturers and users of such formulations. Furthermore, such formulations can be administered to patients using relatively small injection volumes, thereby improving patient experience and compliance. Essentially, the present invention relies on the inherent stability of molecules that are highly soluble in DMSO (and other polar aprotic solvent systems) but relatively poorly soluble in aqueous environments, such as the interstitial fluid of the body (e.g., subcutaneous or intramuscular spaces) into which the formulation is injected.

[0008] Embodiments described herein provide storage-stable compositions (formulations) comprising one or more therapeutically active ingredients (e.g., one or more active pharmaceutical ingredients) that are highly soluble (i.e., at least about 50% soluble, preferably at least about 75% soluble, at least about 80% soluble, at least about 85% soluble, at least about 90% soluble, at least about 95% soluble, or at least about 99% soluble) in aprotic polar solvent systems such as those described herein (particularly DMSO-containing solvent systems), but are lowly soluble (i.e., less than about 50% soluble, less than about 40% soluble, less than about 30% soluble, less than about 25% soluble, less than about 20% soluble, less than about 15% soluble, less than about 10% soluble, less than about 5% soluble, or less than about 1% soluble) in aqueous environments such as the interstitial fluid of a patient's body (e.g., the subcutaneous or intramuscular space) to which the formulation is administered by injection. In certain embodiments, the formulation comprises a therapeutic peptide or small molecule, such as levothyroxine or a salt thereof, a benzodiazepine (e.g., diazepam), or tamsulosin. In preferred embodiments, the active pharmaceutical ingredient is present in the formulation at a concentration sufficient to result in sustained release of the active pharmaceutical ingredient into the bloodstream of a patient into whom the formulation is injected. In other embodiments, the present invention provides methods for making such storage-stable sustained-release therapeutic formulations. In a further embodiment, the present invention provides methods for using the storage-stable sustained-release formulations of the present invention in methods for treating, preventing, and / or diagnosing a particular disease, disorder, or condition in animals, including veterinary animals and humans, suffering from or predisposed to suffering from such disease, disorder, or condition.

[0009] In certain exemplary embodiments, the present invention provides storage-stable, sustained-release levothyroxine formulations useful for the treatment and / or prevention of hypothyroidism, particularly severe hypothyroidism such as myxedema or myxedema coma / crisis, and as an adjunct to certain other therapeutic approaches. In other exemplary embodiments, the present invention provides storage-stable, sustained-release benzodiazepine formulations, e.g., diazepam formulations, useful for the treatment and / or prevention of anxiety, muscle spasms, and seizures, among other diseases and disorders, and as an adjunct to certain other therapeutic approaches. In other exemplary embodiments, the present invention provides storage-stable, sustained-release tamsulosin formulations useful for the treatment and / or prevention of benign prostatic hyperplasia and kidney stones, and as an adjunct to certain other therapeutic approaches.

[0010] Such formulations advantageously utilize the same non-aqueous formulation technology (XeriSol™; Xeris Pharmaceuticals, Inc., Chicago, IL) as currently available immediate-release glucagon rescue products (Gvoke®; Xeris Pharmaceuticals) to address stability and solubility issues of aqueous compositions containing certain small molecules or peptides. Such storage-stable extended-release formulations of the present invention are clear, ready-to-use, non-aqueous solutions prior to injection. Upon administration, e.g., subcutaneously, the small molecule or peptide therapeutic forms a depot due to its poor solubility under physiological conditions, facilitating the sustained release of the therapeutic molecule into the bloodstream, resulting in improved bioavailability, pharmacokinetics, and in some circumstances, sustained release of the therapeutic molecule compared to orally administered compositions or immediate-release parenteral compositions.

[0011] Thus, in certain embodiments, the present invention provides therapeutic formulations comprising (a) at least one therapeutic agent, (b) at least one ionization-stabilizing excipient, and (c) an aprotic polar solvent, which are particularly stable for at least two years under refrigerated conditions (e.g., 2°C to 10°C) and, when administered to a patient, result in therapeutic levels of the therapeutic agent in the patient's bloodstream (i.e., provide sustained release of the therapeutic agent) for an extended period of time compared to an immediate-release formulation containing the same therapeutic agent. According to the present invention, any therapeutic agent that is poorly soluble in an aqueous environment (such as the interstitial fluid of a human or veterinary animal) but readily or highly soluble in an aprotic polar solvent system (such as one containing DMSO) can be advantageously used in the formulations of the present invention. In certain such embodiments, the therapeutic agent is a small molecule or its salt, and can be any small molecule therapeutic agent. Examples of such small molecule therapeutic agents include, but are not limited to, levothyroxine, sumatriptan, ketorolac, and ondansetron. In other such embodiments, the therapeutic agent is a peptide, such as a glucagon peptide, a glucagon analog, a glucagon mimetic, or a salt thereof.

[0012] At least one ionization stabilizing excipient is dissolved in the aprotic solvent in an amount that stabilizes the ionization of the therapeutic agent. In certain aspects, the ionization stabilizing excipient is at a concentration of 0.01 mM to less than 200 mM. The ionization stabilizing excipient can be a proton-donating (e.g., acid) component and / or a proton-accepting (e.g., base) component. The ionization stabilizing excipient can be, but is not limited to, an inorganic acid. In certain embodiments, the inorganic acid can be selected from hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid. The ionization stabilizing excipient can also be an organic acid (an acid having a carboxylic acid-COOH functional group). Non-limiting examples of organic acids include acetic acid, citric acid, malic acid, lactic acid, and amino acids. In certain aspects, the aprotic solvent is DMSO. In certain aspects, the ionization stabilizing excipient is an inorganic acid, particularly sulfuric acid or hydrochloric acid, and the aprotic solvent is DMSO.

[0013] In another aspect, the present invention provides a method for treating, ameliorating, or preventing a disease, condition, or disorder in a patient, such as a veterinary animal or a human, suffering from or predisposed to such a disease, condition, or disorder. A preferred such method according to certain aspects of the present invention comprises introducing an effective amount of a storage-stable sustained-release formulation of the present invention to a patient in need thereof in a manner suitable for promoting release of the therapeutic compound from the formulation into the patient's bloodstream. In certain such embodiments, the formulation is introduced into a subject via parenteral administration, for example, via injection (which may be subcutaneous, intradermal, or intramuscular) or infusion (which may be intravenous, or may be achieved by pump infusion, e.g., continuous or bolus pump infusion, or a combination thereof). In certain aspects, the present invention provides a method for treating or preventing hypothyroidism in a human by administering to the human a storage-stable sustained-release levothyroxine formulation of the present invention.

[0014] In a further aspect, the present invention provides a method for making a storage-stable extended-release therapeutic formulation comprising mixing at least one ionization-stabilizing excipient, an aprotic polar solvent, and at least one therapeutic agent (particularly at least one therapeutic agent that is poorly soluble in an aqueous environment and readily or highly soluble in an aprotic polar solvent system), thereby forming a storage-stable extended-release therapeutic formulation that, when administered to a patient, results in therapeutic levels of the therapeutic agent in the patient's blood for an extended period of time compared to an immediate-release formulation containing the same therapeutic agent.

[0015] To produce the storage-stable, sustained-release therapeutic formulations of the present invention, at least one ionization-stabilizing excipient can be dissolved in an aprotic solvent in an amount sufficient to stabilize the ionization of the therapeutic agent. Suitable such ionization-stabilizing excipients (including, but not limited to, inorganic acids) and desired concentrations for inclusion in the formulations of the present invention include those described in more detail elsewhere herein.

[0016] The formulations disclosed herein may further comprise less than 10, 5, or 3% w / v of a preservative. In certain embodiments, the preservative is benzyl alcohol.

[0017] The formulations disclosed herein may further comprise less than 10, 5, or 3% w / v of one or more disaccharides. In certain embodiments, the disaccharide is about 5.5% w / v of trehalose dihydrate.

[0018] The formulation may further comprise one or more sugar alcohols at less than 10, 5, or 3% w / v. In certain embodiments, the sugar alcohol is about 2.9% (w / v) mannitol.

[0019] In certain embodiments, the formulation may have a freezing point of about 10°C or less, e.g., about 10°C, about 5°C, about 0°C, or less than about 0°C, e.g., less than -20°C, or between -50°C and -70°C.

[0020] Therapeutic molecules typically require an optimal or beneficial ionization profile to exhibit prolonged stability when dissolved in an aprotic polar solvent system. Maintaining a beneficial ionization profile of a therapeutic molecule dissolved in an aprotic polar solvent system can be achieved by using at least one ionization-stabilizing excipient. In certain aspects, the therapeutic molecule does not need to be dried from a buffered aqueous solution before reconstitution in an aprotic polar solvent system. The ability to use existing (e.g., commercially available) devices and avoid the need to dry a therapeutic molecule (e.g., a peptide) from a buffered aqueous solution can save significant time and money throughout various product development stages.

[0021] A stable solution of a therapeutic agent solubilized in a non-aqueous aprotic polar solvent (e.g., DMSO) can be prepared by adding a specific amount of a compound or combination of compounds that function as an ionization-stabilizing excipient. Without wishing to be bound by theory, it is believed that the ionization-stabilizing excipient may act as a proton source (e.g., a molecule that can donate a proton to a therapeutic molecule) in the aprotic polar solvent system that can protonate an ionogenic group on the therapeutic molecule, such that the therapeutic molecule has an ionization profile that exhibits improved physical and chemical stability in the aprotic polar solvent system. Alternatively, the ionization-stabilizing excipient may act as a proton sink (e.g., a molecule or moiety that can accept / remove a proton from a therapeutic molecule), such that the therapeutic molecule has an ionization profile that exhibits improved physical and chemical stability in the aprotic polar solvent system.

[0022] Certain embodiments relate to formulations comprising an ionization stabilizing excipient at a concentration of at least 0.01, 0.1, 0.5, 1, 10, or 50 mM to 10, 50, 75, 100, 500, 1000 mM, at most 0.01, 0.1, 0.5, 1, 10, or 50 mM to 10, 50, 75, 100, 500, 1000 mM, or about 0.01, 0.1, 0.5, 1, 10, or 50 mM to 10, 50, 75, 100, 500, 1000 mM, or up to the solubility limit of the ionization stabilizing excipient in the aprotic polar solvent system. In certain aspects, the concentration of the ionization stabilizing excipient is about 0.1 mM to about 100 mM, particularly about 1 mM to about 10 mM, e.g., about 1 mM, about 2 mM, about 3 mM, about 4 mM, about 5 mM, about 6 mM, about 7 mM, about 8 mM, about 9 mM, and about 10 mM (and all ranges and concentrations therebetween). In certain embodiments, the ionization stabilizing excipient can be a suitable inorganic acid, such as hydrochloric acid, sulfuric acid, nitric acid, etc. In certain aspects, the ionization stabilizing excipient can be an organic acid, such as an amino acid, an amino acid derivative, or a salt of an amino acid or amino acid derivative (examples include glycine, trimethylglycine (betaine), glycine hydrochloride, and trimethylglycine (betaine) hydrochloride). In further aspects, the amino acid can be glycine or the amino acid derivative trimethylglycine. In certain aspects, the peptide has fewer than 150, 100, 75, 50, or 25 amino acids. In a further aspect, the aprotic solvent system comprises DMSO. The aprotic solvent can be deoxygenated, for example, deoxygenated DMSO. In certain embodiments, the formulation can be prepared by first adding an ionization-stabilizing excipient to the aprotic polar solvent system, and then adding the therapeutic molecule. Alternatively, the therapeutic molecule can be first solubilized in the aprotic polar solvent system, and then adding the ionization-stabilizing excipient. In a further aspect, the ionization-stabilizing excipient and the therapeutic molecule can be simultaneously solubilized in the aprotic polar solvent system. In certain aspects, the therapeutic agent is glucagon, glucagon analog, or a salt thereof.

[0023] Another aspect of the present invention is directed to a method for stably formulating a therapeutic agent (e.g., a peptide or small molecule), comprising the steps of: (a) calculating or determining appropriate ionization stabilizing excipients (e.g., proton concentrations) necessary to achieve a stabilized ionization profile of the targeted therapeutic agent (e.g., a peptide or small molecule) in an aprotic polar solvent system; (b) mixing at least one ionization stabilizing excipient with the aprotic polar solvent system to achieve a suitable ionization environment that provides the ionization profile determined in step (a); and (c) solubilizing the targeted therapeutic agent in an aprotic solvent having a suitable environment to physically and chemically stabilize the therapeutic agent. In certain non-limiting aspects, the therapeutic agent is chemically or physically stable at room temperature, refrigerated temperatures (e.g., about 2°C to about 10°C, or about 2°C to about 8°C, or about 2°C, about 3°C, about 4°C, about 5°C, about 6°C, about 7°C, about 8°C, about 9°C, or about 10°C), or subzero temperatures (e.g., about −4°C to about −80°C, or about −4°C, about −10°C, about −15°C, about −20°C, about −25°C, about −40°C, about −45°C, about −50°C, about −60°C, about −70°C, or about −80°C) for at least or about 0.25, 0.5, 1, 2, 3, 4, or 5 years, more preferably about 0.25 to about 3 years, and even more preferably at least about 6 months to about 2 years. In certain aspects, dissolving the therapeutic agent and adding the ionization stabilizing excipient to the aprotic polar solvent system can be performed in any order or simultaneously. However, the inventors have found that to maximize the dissolution, stability, and / or bioactivity of some therapeutic agents, such as levothyroxine, it is preferable to first mix the ionization stabilizing excipient with the aprotic polar solvent and then dissolve the therapeutic agent in the mixture. However, other formulations of the present invention can be prepared by first dissolving the therapeutic agent in the aprotic polar solvent and then adding the ionization stabilizing excipient to the solution immediately thereafter (e.g., within about 5 minutes), or the ionization stabilizing excipient and the therapeutic agent can be added or dissolved simultaneously in the aprotic polar solvent system.One or more additional formulation components (e.g., sustained-release modifiers (e.g., polymeric compounds such as poly(lactic-co-glycolic acid) or PLGA; see U.S. Patent Publication No. US 2021 / 0401945 A1; incorporated herein by reference in its entirety), preservatives, surfactants, polysaccharides, sugar alcohols, etc.) can be incorporated into the formulation either before or after the addition of the therapeutic agent. The concentration of the therapeutic agent and / or ionization-stabilizing excipient added to the solution can be between 0.01, 0.1, 1, 10, 100, 1000 mM, or up to its solubility limit (including all values ​​and ranges therebetween), as described in more detail elsewhere herein. In certain aspects, the aprotic polar solvent system is deoxygenated. In further aspects, the aprotic polar solvent in the solvent system comprises, consists essentially of, or consists of DMSO or deoxygenated DMSO.

[0024] In a further aspect of the present invention, methods for treating or preventing conditions, diseases, disorders, etc. are disclosed, comprising administering to a subject in need thereof a formulation of the present invention in an amount effective to treat or prevent the condition, disease, disorder, etc. Any suitable dosage of a therapeutic agent (e.g., a protein, peptide, or small molecule) can be administered in the methods of the present invention. The dosage will, of course, vary depending on known factors, such as the pharmacodynamic properties of the particular compound, salt, or combination; the age, health, or weight of the subject; the nature and extent of the symptoms; the drug and metabolic characteristics of the patient; the type of concomitant treatment; the frequency of treatment; and the desired effect. In certain aspects, hypothyroidism can be treated or prevented by administering a formulation described herein containing an effective amount of levothyroxine. In other aspects, hypoglycemia can be treated by administering a formulation described herein containing an effective amount of glucagon.

[0025] The stable formulations described herein are useful for parenteral injection of any therapeutic agent (protein, peptide, and / or small molecule) that has limited or insufficient stability or solubility in aqueous environment.In certain aspects, the formulations described herein are provided as injection formulations.The injection formulations can be administered to the epidermis layer, dermis layer, subcutaneously or intramuscularly of patients.In certain aspects, the formulations are administered to the skin, particularly intradermally or subcutaneously.

[0026] definition Terms such as "container," "reservoir," "infusion set," "pump," "product flow path," "fluid flow path," and the like should be interpreted as interchangeable and equivalent, referring to components that directly contact the administered or stored product, which may interact with the component and its surface. These terms connote any and all components that the product may come into contact with during storage (e.g., pump reservoir) and delivery (e.g., pump and fluid flow path within an infusion set when connected in series to the pump). The term "infusion set," as used herein, can be interpreted to include both self-contained infusion sets (i.e., those contained within patch pumps) and the complete tubing system, typically external to the pump, that connects the pump to the pump user. In certain configurations, external infusion sets include cannulas (e.g., for subcutaneous administration), adhesive mounts, quick disconnects, and pump cartridge connectors (e.g., Luer connectors).

[0027] The terms "formulation" and "composition" may be used interchangeably herein and, as used herein, refer to a mixture of at least two components to produce a preparation that includes all of those components, some of those components, or a complex or reaction mixture or reactant resulting from the mixing of those components.

[0028] The term "dissolution," as used herein, refers to the process by which a substance in a gaseous, solid, or liquid state becomes a solute, a dissolved component of a solvent, forming a solution of the gas, liquid, or solid in the solvent. In certain aspects, a therapeutic agent or excipient, such as an ionizable stabilizing excipient or sustained-release modifier, or other component, is present in an amount up to its solubility limit or is completely solubilized. The term "dissolution" refers to the incorporation of a gas, liquid, or solid into a solvent to form a solution.

[0029] The term "elastomer," as used herein, refers to a natural or synthetic polymer that has elastic properties. The terms "elastomer" and "rubber" may be used interchangeably herein.

[0030] The term "excipient," as used herein, refers to a natural or synthetic substance (a component other than the active ingredient) formulated with an active or therapeutic ingredient of a pharmaceutical for purposes of stabilization, bulking, or to provide a therapeutic enhancement to the active ingredient in the final dosage form, e.g., to facilitate drug absorption, reduce viscosity, increase or decrease aqueous or non-aqueous solubility, adjust osmolality, reduce injection site discomfort, lower the freezing point, or enhance stability. Excipients can also be useful in aiding in in vitro stability, e.g., preventing denaturation or aggregation during the expected storage period, as well as aiding in handling of the active agent of interest during the manufacturing process, e.g., by promoting powder flow or non-stick properties.

[0031] In the context of the present invention, a "small molecule drug" is a biologically active compound (and its salts) that can produce a desired, beneficial, and / or pharmacological effect in a subject. These "small molecule drugs" are organic or inorganic compounds. Therefore, in the context of the present invention, small molecule drugs are not polymeric compounds. Typically, small molecule drugs have a molecular weight of less than approximately 1000 daltons. Certain small molecule drugs are "moisture sensitive" in that they become increasingly unstable in the presence of water. In addition, salts that can be used with small molecule drugs are known to those skilled in the art and include salts with inorganic acids, organic acids, inorganic bases, or organic bases.

[0032] The term "therapeutic agent" or "therapeutic" encompasses proteins, peptides, small molecule drugs, and pharmaceutically acceptable salts thereof. Useful salts are known to those skilled in the art and include salts with inorganic acids, organic acids, inorganic bases, or organic bases. Therapeutic agents useful in the present invention are proteins, peptides, and small molecule compounds that, alone or in combination with other pharmaceutical excipients or inactive ingredients, provide a desired, beneficial, and often pharmacological effect when administered to humans or animals. Therapeutic agents may also be interchangeably described herein as "active pharmaceutical ingredients" ("APIs").

[0033] The terms "peptide" and "peptide compound" refer to amino acid or amino acid-like (peptidomimetic) multimers of up to about 200 amino acid residues linked together by amide (CONH) or other linkages. In certain aspects, peptides can be up to 150, 100, 80, 60, 40, 20, or 10 amino acids. "Protein" and "proteinaceous compound" refer to multimers of more than 200 amino acid residues linked together by amide bonds. These terms include analogs, derivatives, agonists, antagonists, and pharmaceutically acceptable salts of any of the peptide or proteinaceous compounds disclosed herein. These terms also include peptides, proteins, peptide compounds, and proteinaceous compounds having D-amino acids, modified, derivatized, or naturally occurring amino acids in the D or L configuration, and / or peptidomimetic units as part of their structure.

[0034] "Analog" and "analog," when referring to a peptide or protein, refer to a modified peptide or protein in which one or more amino acid residues of the peptide or protein have been substituted with other amino acid residues, or one or more amino acid residues have been deleted from the peptide or protein, or one or more amino acid residues have been added to the peptide or protein, or any combination of such modifications. Such addition, deletion, or substitution of amino acid residues can occur at any point, or points, along the primary structure that makes up the peptide, including the N-terminus of the peptide or protein and / or the C-terminus of the peptide or protein.

[0035] A "derivative," in reference to a parent peptide or protein, refers to a chemically modified parent peptide or protein or analog thereof, in which at least one substitution is not present in the parent peptide or protein or analog. One such non-limiting example is a covalently modified parent peptide or protein. Typical modifications are amides, carbohydrates, alkyl groups, acyl groups, esters, pegylation, etc.

[0036] A "single-phase solution" refers to a solution prepared from a therapeutic agent dissolved in a solvent or solvent system (e.g., a mixture of two or more solvents (e.g., a solvent and a co-solvent)) in which the therapeutic agent is completely dissolved in the solvent or solvent system and no particulate matter is visible, such that the solution can be described as optically clear. A single-phase solution may also be referred to as a "single-phase system," which is distinguished from a "two-phase system," in that the latter is formed from particulate matter (e.g., a powder) suspended in a fluid.

[0037] "Inhibition," "reduction," or any variation of these terms includes any measurable decrease or complete inhibition that achieves the desired result.

[0038] "Effective" or "therapeutic" or "preventive" or any variation of these terms means sufficient to achieve a desired, expected, or intended result.

[0039] "Chemical stability," when referring to a therapeutic agent, refers to the formation of an acceptable proportion of degradation products via chemical pathways, such as oxidation and / or hydrolysis and / or fragmentation and / or other chemical degradation pathways. In particular, formulations of the type described herein can be considered chemically stable if no more than about 20% degradation products are formed after at least one year of storage at the product's intended storage temperature (e.g., refrigerated storage or storage below zero degrees Celsius), or after one, two, or preferably three months of storage under accelerated conditions (25°C / 60% relative humidity). In some embodiments, a chemically stable formulation has less than 30%, 25%, 20%, 15%, 10%, 5%, 4%, 3%, 2%, or 1% degradation products formed after extended storage at the product's intended storage temperature.

[0040] "Physical stability," when referring to a therapeutic agent, refers to the formation of an acceptable proportion of aggregates (e.g., dimers, trimers, and higher forms). In particular, a formulation is considered physically stable if about 15% or less aggregates form after at least one year of storage at the product's intended storage temperature (e.g., refrigerated storage, storage at or below zero degrees), or after one month, two months, and preferably at least three months of storage at 25°C / 60% relative humidity. In some embodiments, a physically stable formulation has less than 15%, less than 10%, less than 5%, less than 4%, less than 3%, less than 2%, or less than 1% aggregates formed after extended storage at the product's intended storage temperature.

[0041] A "stable formulation" refers to a formulation in which at least about 65% of the therapeutic agent (e.g., a small molecule, peptide, or salt thereof) remains chemically and physically stable after storage at room temperature for at least one month or storage at refrigerated or sub-zero temperatures for up to at least one year. Particularly preferred formulations are those in which at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% of the therapeutic agent remains chemically and physically stable under these storage conditions. Particularly preferred stable formulations are those that do not exhibit degradation after sterilizing irradiation (e.g., gamma, beta, or electron beam).

[0042] As used herein, "parenteral injection" refers to the administration of a therapeutic agent (e.g., a peptide or small molecule) through a route other than the alimentary canal—any administration not via the digestive tract—e.g., intravenous infusion, intranasal administration, buccal administration, transdermal administration, or injection under or through one or more layers of the skin or mucosa of an animal, e.g., a human. Standard parenteral injections are performed into subcutaneous, intramuscular, or intradermal tissues of an animal, e.g., a human. These deeper sites are targeted because the tissues expand more readily than shallower skin sites to accommodate the injection volumes required to deliver most therapeutic agents, e.g., 0.1 to 3.0 cc (mL).

[0043] The term "intradermal" includes administration into the epidermal or dermal skin layers.

[0044] As used herein, the term "aprotic polar solvent" refers to a polar solvent that does not contain acidic hydrogen and therefore does not act as a hydrogen bond donor. Aprotic polar solvents include, but are not limited to, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), ethyl acetate, n-methylpyrrolidone (NMP), dimethylacetamide (DMA), and propylene carbonate.

[0045] As used herein, the term "aprotic polar solvent system" refers to a solution in which the solvent is a single aprotic polar solvent (e.g., neat DMSO) or a mixture of two or more aprotic polar solvents (e.g., a mixture of DMSO and NMP), or a mixture of at least one aprotic polar solvent and at least one other pharmaceutically acceptable solvent system, one non-limiting example of which would be a solvent system comprising an aprotic polar solvent (e.g., DMSO) and a protic polar solvent (e.g., propylene glycol). In a further aspect, the term "aprotic polar solvent system" refers to a solution in which the solvent is one or more aprotic polar solvents mixed with an amount of water, for example, water, in a v / v ratio of at least about 99.9% aprotic solvent to about 0.1% water to a maximum of at least about 50% aprotic solvent to water.

[0046] As used herein, "residual moisture" may refer to the moisture (typically, residual water) remaining in a drug powder after preparation by the manufacturer / supplier. Typical powders often have a residual moisture content ranging up to 10% (w / w). When these powders are dissolved in an aprotic polar solvent system, the residual moisture in the powder is incorporated into the formulation. Furthermore, aprotic polar solvents may also contain a certain level of residual moisture. For example, a newly opened bottle of USP-grade DMSO may contain up to 0.1% (w / w) moisture. Residual moisture differs from "added moisture," in which water is intentionally added to a formulation, for example, to act as a cosolvent or to depress the freezing point of an aprotic polar solvent system. Moisture can also be introduced into a formulation upon the addition of ionizable stabilizing excipients (e.g., through the addition of an inorganic acid (e.g., 1N HCl or H2SO4) from an aqueous stock solution) or through the addition of water (e.g., water for injection). The total water content (% w / w unless otherwise stated) in a formulation immediately after preparation is due to contributions from both residual and added water. Such formulations may be further defined as "non-aqueous," which for purposes of this disclosure encompasses formulations containing less than about 50% water.

[0047] As used herein, a "device flow path" refers to a portion of a device that may come into contact with a formulation / solution / solvent during administration of the formulation / solution / solvent to a subject using the device. In some aspects, the device may be an infusion set in series with a pump that can parenterally administer the formulation / solution / solvent to a subject through various needles and / or tubing. In other aspects, the device may be a patch pump that is attached directly to the patient and does not require the use of an external infusion set connected in series with the pump.

[0048] The terms "about" or "approximately" or "substantially unchanged" are defined as closely as understood by one of ordinary skill in the art, and in one non-limiting embodiment, the term is defined as within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%. Additionally, "substantially non-aqueous" refers to less than 5%, 4%, 3%, 2%, 1% or less water by weight or volume.

[0049] A "pharmaceutically acceptable" ingredient, excipient, or component is one that is suitable for use in humans and / or animals without producing excessive adverse side effects (e.g., toxicity, irritation, and allergic response) commensurate with a reasonable benefit / risk ratio.

[0050] "Pharmaceutically acceptable carrier" means a pharmaceutically acceptable solvent, suspending agent, or vehicle for delivering a drug compound of the present invention to a mammal, eg, a human.

[0051] As used herein, an "ionization-stabilizing excipient" is an excipient that establishes and / or maintains a particular ionization state for a therapeutic agent. In certain aspects, an ionization-stabilizing excipient may be or includes a molecule that, under appropriate conditions, donates at least one cation, particularly at least one divalent cation, or is a cation (particularly a divalent cation)-donating compound or source.

[0052] As used herein, a "mineral acid" is an acid derived from one or more inorganic compounds. Thus, an inorganic acid may also be referred to as an "inorganic acid." Inorganic acids can be monoprotic or polyprotic (e.g., diprotic, triprotic, etc.). Non-limiting examples of inorganic acids include hydrochloric acid (HCl), nitric acid (HNO), sulfuric acid (HSO), and phosphoric acid (HPO).

[0053] As used herein, an "inorganic base" (which may equivalently and alternatively be referred to as an "inorganic base") is a base derived from one or more inorganic compounds. Many, but not all, inorganic bases are typically classified as "strong bases," and non-limiting examples of inorganic bases include sodium hydroxide (NaOH), potassium hydroxide (KOH), magnesium hydroxide (Mg(OH)), and calcium hydroxide (Ca(OH)).

[0054] As used herein, an "organic acid" is an organic compound that has acidic properties (i.e., can function as a proton source). A carboxylic acid, such as acetic acid or citric acid, is an example of an organic acid. Other known examples of organic acids include, but are not limited to, alcohols, thiols, enols, phenols, and sulfonic acids. Organic acids can be monoprotic or multiprotic (e.g., diprotic, triprotic, etc.).

[0055] As used herein, an "organic base" is an organic compound that has basic properties (i.e., can function as a proton acceptor / sink). Many, but not all, organic bases contain a nitrogen atom (e.g., amines), and non-limiting examples of organic bases include amino acids (e.g., histidine, arginine, lysine), pyridine, imidazole, and tromethamine. An organic base can accept one or more protons per molecule.

[0056] "Charge profile," "charge state," "ionization," "ionization state," and "ionization profile" may be used interchangeably to refer to the ionization state based on the protonation and / or deprotonation of the ionogenic groups of the peptide.

[0057] As used herein, a "co-formulation" is a formulation containing two or more therapeutic agents dissolved in an aprotic polar solvent system. The therapeutic agents may belong to the same class (e.g., a co-formulation containing two or more therapeutic peptides, such as insulin and pramlintide, or glucagon and GLP-1), or the therapeutic agents may belong to different classes (e.g., a co-formulation containing one or more therapeutic small molecules and one or more therapeutic peptide molecules, such as GLP-1 and lisofylline).

[0058] When used in conjunction with the word "comprising" in the claims and / or specification, the use of the words "a" or "an" can mean "one," but can also mean "one or more," "at least one," and "one or more than one."

[0059] "Comprising" (and any form of comprising, e.g., "comprise" and "comprises"), "having" (and any form of having, e.g., "have" and "has"), "including" (and any form of including, e.g., "includes" and "include") or "containing" (and any form of containing, e.g., "contains" and "contain") is inclusive and open-ended and does not exclude additional, unmentioned elements or method steps.

[0060] Other objects, features, and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and examples, while indicating specific embodiments of the present invention, are given by way of illustration only. In addition, it is contemplated that changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this detailed description. [Brief explanation of the drawings]

[0061] The following drawings form part of the present specification and are included to further demonstrate certain aspects of the present invention. The invention may be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented herein. [Figure 1] 1A-1B are a set of line graphs showing mean plasma levothyroxine concentrations in minipigs administered various formulations of the present invention plotted on a linear scale (FIG. 1A) or a logarithmic scale (FIG. 1B). [Figure 2] 1 is a box plot showing the mean Tmax (hr) of levothyroxine formulations of the present invention administered subcutaneously to minipigs. [Figure 3] 1 is a box plot showing the mean Cmax (ng / mL) of levothyroxine formulations of the present invention administered subcutaneously to minipigs. [Figure 4] 1 is a box plot showing the mean AUClast (hr*ng / ml) of levothyroxine formulations of the present invention administered subcutaneously to minipigs. [Figure 5] 1 is a box plot showing the mean AUC144-336 (hr*ng / ml) of levothyroxine formulations of the present invention administered subcutaneously to minipigs. [Figure 6] 6A-6B are a pair of line graphs showing mean baseline unadjusted plasma levothyroxine concentrations in minipigs administered 5 mg / mL or 10 mg / mL levothyroxine formulations of the present invention (XP-8121-5 and XP-8121-10, respectively), plotted on a linear scale (FIG. 6A) or a logarithmic scale (FIG. 6B). [Figure 7] 7A-7B are a pair of line graphs showing mean baseline-adjusted plasma levothyroxine concentrations in minipigs administered 5 mg / mL or 10 mg / mL levothyroxine formulations of the present invention (XP-8121-5 and XP-8121-10, respectively), plotted on a linear scale (FIG. 7A) or a logarithmic scale (FIG. 7B). [Figure 8] 1 is a line graph plotting mean baseline-adjusted plasma diazepam concentrations (ng / mL) on a linear scale in minipigs administered a 50 mg / mL or 100 mg / mL diazepam formulation of the present invention. [Figure 9] FIG. 1 is a graphical representation of the study design for a human clinical trial designated XP-8121-108 to examine the pharmacokinetics of subcutaneous (SC) administration of certain levothyroxine-containing formulations of the present invention versus oral (PO) administration of a tablet dosage form (Synthroid®). [Figure 10] 10A-10B are a pair of line graphs showing the mean baseline-adjusted plasma levothyroxine concentrations in human subjects receiving a 10 mg / mL levothyroxine formulation of the present invention (XP-8121) subcutaneously (SC) at 600 μg, 1200 μg, or 1500 μg compared to Synthroid® 600 μg administered orally (PO) in the XP-8121-108 study. Results are plotted on a linear scale (FIG. 10A) or a semi-logarithmic scale (FIG. 10B). [Figure 11] FIG. 11A is a box plot showing the mean baseline-adjusted Tmax (hr) and FIG. 11B is a bar graph showing the mean baseline-adjusted half-life (T1 / 2, hr) for levothyroxine formulations of the invention administered subcutaneously to human subjects in the XP-8121-108 clinical trial. [Figure 12]12A-12B are a pair of bar graphs showing the mean baseline-adjusted C (ng / mL) (FIG. 12A) or mean baseline-adjusted AUC (ng*hr / mL) (FIG. 12B) for levothyroxine formulations of the invention administered subcutaneously to human subjects in the XP-8121-108 clinical trial. [Figure 13] 13A-13B are a pair of line graphs showing the mean baseline-adjusted Cmax normalized to levothyroxine dose in human subjects subcutaneously (SC) administered 600 μg, 1200 μg, or 1500 μg of a 10 mg / mL levothyroxine formulation of the present invention (XP-8121) in the XP-8121-108 study. Results are plotted on a linear scale (FIG. 13A) or a logarithmic scale (FIG. 13B). [Figure 14] 14A-14B are a pair of line graphs showing the mean baseline-adjusted AUClast normalized to levothyroxine dose in human subjects subcutaneously (SC) administered 600 μg, 1200 μg, or 1500 μg of a 10 mg / mL levothyroxine formulation of the present invention (XP-8121) in the XP-8121-108 study. Results are plotted on a linear scale (FIG. 14A) or a logarithmic scale (FIG. 14B). DETAILED DESCRIPTION OF THE INVENTION

[0062] Detailed Description of the Invention Standard small molecules, peptides, and protein molecules, when formulated as aqueous solutions, can be susceptible to a variety of physical and chemical degradation pathways. For many of these therapeutic molecules, degradation pathways catalyzed, mediated, and / or accelerated by water (e.g., hydrolysis, racemization, deamidation) are inevitable, and as a result, the molecules cannot be adequately stabilized. For this reason, many therapeutic agents cannot be formulated as stable solutions for parenteral injection, but instead are prepared as powders that are reconstituted immediately before use.

[0063] To address the physical and / or chemical instability that many therapeutic molecules exhibit in water, formulations can be prepared in which the therapeutic agent is dissolved in a biocompatible non-aqueous liquid, such as aprotic polar solvents (e.g., DMSO). Previous non-aqueous formulations have been based, at least in part, on the premise that limiting the water content of the formulation promotes physical and chemical stability by inhibiting water-mediated degradation pathways. Many of these known formulations limit the water content to a maximum of 10% (w / w).

[0064] The use of aprotic polar solvents to prepare non-aqueous therapeutic formulations that inhibit many common degradation pathways, particularly those involving water, can significantly improve the stability of solubilized or dissolved therapeutic molecules. However, problems remain with the compositions and methods disclosed in the art. In particular, directly dissolving therapeutic molecules in aprotic polar solvents is not a suitable approach for preparing stable compositions of most therapeutic molecules. When various therapeutic agents are directly solubilized in DMSO, for example, levothyroxine at a concentration of 5 mg / mL, discoloration and the formation of degradation products occur within one day of refrigerated storage. For a composition containing only levothyroxine and DMSO, 5 mg / mL corresponds to approximately 0.45% (w / w) of levothyroxine, indicating that even at relatively low concentrations, direct dissolution in an aprotic polar solvent system by itself cannot prevent degradation and / or gelation of therapeutic molecules. Furthermore, even therapeutic molecules that are not susceptible to chemical degradation in aprotic polar solvent systems may form insoluble aggregates when directly solubilized in aprotic polar solvent systems.

[0065] Without wishing to be bound by theory, it is believed that therapeutic molecules require a specific ionization profile to exhibit improved or optimal stability and solubility when formulated in aprotic polar solvent systems. An ionization profile refers to the charge state acquired by protonation and / or deprotonation of ionogenic groups of a therapeutic molecule, conferring an overall positive, negative, or neutral charge state to the molecule. For example, protonation of ionogenic amino acid residues (e.g., arginine, lysine, aspartic acid, glutamic acid) constituting a therapeutic peptide can confer an overall positive charge to the molecule in solution. Alternatively, deprotonation of ionogenic amino acid residues can confer an overall negative charge to the molecule in solution. While the non-limiting examples used herein describe protonated (i.e., positively charged) molecules, deprotonation of ionogenic amino acid residues in a therapeutic peptide molecule is also considered within the scope of the present invention. In such embodiments, the relatively long-range electrostatic repulsion between positively charged API molecules can inhibit short-range hydrophobic interactions that can lead to physical instability (e.g., precipitation, aggregation, and / or gelation). Therefore, in the absence of sufficient protonation (i.e., an optimal or beneficial ionization profile), therapeutic molecules dissolved in an aprotic polar solvent system can become physically unstable, leading to the formation of soluble and / or insoluble aggregates and other degradation products. Therefore, it may be necessary to include at least one excipient capable of imparting an ionization profile that enhances physical and / or chemical stability to the active agent in the aprotic polar solvent system, at a concentration sufficient to function as an ionization stabilizer. The appropriate concentration of ionization-stabilizing excipient added to the solution depends on several factors, including, but not limited to, the chemical structure of the ionization-stabilizing excipient, the chemical structure of the active agent, the concentration of the active agent, the solvent system used, the presence of cosolvents, and the presence and respective concentrations of additional excipients or formulation components.

[0066] Certain compositions and methods are designed to establish optimal ionization profiles for therapeutic molecules before they are solubilized in an aprotic polar solvent system. For example, peptide powder from a supplier / manufacturer is first dissolved in a buffered aqueous solution, and the pH of the buffered aqueous peptide solution is set to that for optimal stability and solubility of the individual peptide. The peptide is then dried from the aqueous solution (e.g., via lyophilization or spray drying) to form a powder, so that the ionization profile of the peptide molecules in the powder can be approximately equivalent to the ionization profile of the peptide molecules in the aqueous solution before drying. When the peptide powder is then solubilized in an aprotic polar solvent system, the ionization profile of the peptide molecules can be approximately equivalent to the ionization profile of the peptide molecules in the powder. Thus, the ionization profile of peptide molecules in aprotic polar solvent systems is approximately equivalent to the ionization profile of peptide molecules in buffered aqueous solutions (see, e.g., U.S. Patent Nos. 9,649,364, 10,485,850, and 11,020,403; the disclosures of which are incorporated herein by reference in their entireties).

[0067] The need to dry therapeutic molecules from buffered aqueous solutions to optimize the molecule's ionization profile and provide pH memory before solubilizing them in aprotic polar solvents often imposes significant additional costs, both time and money, on the pharmaceutical manufacturing process. In particular, the drying process is known to impose various burdens on therapeutic molecules, and additional excipients (e.g., cryoprotectants such as trehalose and sucrose, and / or surfactants such as polysorbate 80) must be included in the aqueous solution in amounts sufficient to protect the therapeutic molecule, thereby increasing the cost and complexity of the formulation. Furthermore, drying processes (e.g., spray drying, freeze drying) often must be optimized for a given therapeutic molecule both during initial research and development when the process is first developed, at a research scale, and then during manufacturing when the process is scaled up and transferred to equipment and facilities capable of producing commercial-scale batches. As a result, the combination of initial development and optimization of a drying process for a given therapeutic molecule can be very expensive, combined with the time and costs associated with both transferring the method and incorporating additional steps in the manufacturing process. Without wishing to be bound by theory, it is believed that by providing at least one ionization-stabilizing excipient in a sufficient amount to achieve an appropriate or optimal ionization profile of a therapeutic molecule, electrostatic repulsion between therapeutic molecules of the same charge polarity (i.e., negatively or positively charged) can be sufficient in magnitude to prevent physical degradation (e.g., through short-range hydrophobic interactions between molecules that result in aggregation). This is particularly important for molecules that exhibit a tendency to aggregate in solution, especially when the concentration of the molecule in solution becomes high. Furthermore, by controlling and optimizing the degree of ionization (i.e., protonation or deprotonation) of a therapeutic agent, chemical degradation can be minimized, for example, because excessive protonation can promote chemical destabilization through decomposition reactions, such as oxidation (e.g., oxidation of methionine residues) and fragmentation (e.g., cleavage of the peptide backbone).Thus, for some therapeutic molecules, an optimal or beneficial ionization profile may be achieved through protonation or deprotonation so that physical and / or chemical decomposition reactions are minimized. For therapeutic small molecules or peptides, the degree of ionization (i.e., protonation or deprotonation) required for stabilization, and therefore the amount of ionizable stabilizing excipient required in solution, may depend, among other things, on the structure of the therapeutic molecule and its concentration in solution.

[0068] Each molecule functioning as an ionization-stabilizing excipient may exhibit a certain tendency to donate or accept protons to or from the therapeutic molecule and / or additional drug substance / powdered components (e.g., salts, counterions, buffer molecules, etc.) within a given solvent system; the tendency to donate a proton may be expressed as the molecule's relative acidic strength, and the tendency to accept a proton may be expressed as the molecule's relative basic strength. As a non-limiting example, for a fixed concentration of proton-donating molecules (and, for simplicity, assuming only monoprotic molecules in this example), molecules with higher acidic strength may protonate the therapeutic molecule to a greater extent than weaker acids. Thus, the concentration of a given proton-donating molecule (ionization-stabilizing excipient) required to achieve a suitable or optimal ionization profile for a therapeutic molecule may be inversely proportional to its acidic strength. These and other non-limiting aspects of the present invention are disclosed herein.

[0069] The formulation can include an ionization stabilizing excipient at a concentration of at least about 0.01, 0.1, 0.5, 1, 10, 15, 20, 25, 30, 35, 40, 45, or 50 mM (and all ranges and concentrations therebetween) to at most about 10, 15, 20, 25, 30, 50, 75, 100, 500, or 1000 mM (and all ranges and concentrations therebetween), or up to the solubility limit of the ionization stabilizing excipient in the aprotic polar solvent system. The appropriate amount of ionization stabilizing excipient to include can be readily determined based on the charge profile of the therapeutic agent being solubilized in the aprotic polar solvent system. In particular, the amount of ionization stabilizing excipient optimally added to the aprotic polar solvent is sufficient to provide about 2- to 3-fold moles of acid per mole of therapeutic agent relative to the concentration of API in the final formulation (e.g., about 14 mM acid for a 5 mg / mL (about 6.4 mM) solution of levothyroxine sodium; about 10 mM acid for a 5 mg / mL (about 5 mM) solution of levothyroxine free acid), i.e., a molar concentration ratio of ionization stabilizing excipient to therapeutic agent of about 2:1 to about 3:1, preferably about 2.5:1. In certain aspects, the concentration of the ionizable stabilizing excipient is from about 0.1 mM to about 100 mM, particularly from about 1 mM to about 35 mM, e.g., about 1 mM, about 2 mM, about 5 mM, about 10 mM, about 15 mM, about 20 mM, about 25 mM, about 30 mM, and about 35 mM, and all ranges and concentrations therebetween. Certain such aspects include an ionizable stabilizing excipient at a concentration selected from the range of about 15 mM to about 32 mM, e.g., about 15 mM, about 16 mM, about 17 mM, about 18 mM, about 19 mM, about 20 mM, about 21 mM, about 22 mM, about 23 mM, about 24 mM, about 25 mM, about 26 mM, about 27 mM, about 28 mM, about 29 mM, about 30 mM, about 31 mM, and about 32 mM, and all ranges and concentrations therebetween. In certain such aspects, the formulations of the present invention include an ionizable stabilizing excipient at a concentration selected from the range of about 26 mM to about 32 mM, particularly about 26 mM, about 27 mM, about 28 mM, about 29 mM, about 30 mM, about 31 mM, and about 32 mM, and all ranges and concentrations therebetween. In certain aspects, the ionizable stabilizing excipient may be a suitable inorganic acid, such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and the like.Particularly preferred inorganic acids are hydrochloric acid and sulfuric acid. In certain aspects, the ionizable stabilizing excipient may be an organic acid, such as an amino acid, an amino acid derivative, or a salt of an amino acid or an amino acid derivative (examples include glycine, trimethylglycine (betaine), glycine hydrochloride, and trimethylglycine (betaine) hydrochloride). In a further aspect, the amino acid may be glycine or the amino acid derivative trimethylglycine.

[0070] In certain aspects, the aprotic polar solvent can be deoxygenated before preparation of the formulation. Many different techniques can be used in the context of the present invention to deoxygenate or remove oxygen from the aprotic polar solvent (e.g., degassing or deoxygenation). For example, it is contemplated that deoxygenation can remove oxygen dissolved in the liquid aprotic polar solvent by the liquid alone, by the liquid and other solute molecules (e.g., micelles, cyclodextrins, etc.), or by other solute molecules alone, but is not limited thereto. Non-limiting examples of deoxygenation techniques include placing the aprotic polar solvent under reduced pressure and / or heating the liquid to reduce the solubility of dissolved gases, fractional distillation, membrane degassing, displacement with an inert gas, use of a reducing agent, freeze-degass-thaw cycles, or long-term storage in an airlocked container. In one embodiment, the aprotic polar solvent is deoxygenated by vacuum degassing. In another embodiment, the aprotic polar solvent is deoxygenated using a degassing device. In one example, the degasser is a tray-type or cascade-type degasser. In another example, the degasser is a spray-type degasser. In yet another embodiment, the aprotic polar solvent is deoxygenated using a gas-liquid separation membrane. In one example, the aprotic polar solvent is degassed using a gas-liquid separation membrane and reduced pressure. In one embodiment, a non-oxygen gas (e.g., N2) is bubbled through the liquid to replace or reduce oxygen in the aprotic polar solvent. In one example, the gas bubbled through the aprotic polar solvent is argon, helium, nitrogen, an inert gas, and / or hydrogen gas, preferably nitrogen gas. In another example, the gas is bubbled through the aprotic polar solvent using a gas strip column. In yet another embodiment, the aprotic polar solvent is deoxygenated using one or more reducing agents. Non-limiting examples of reducing agents include ammonium sulfite, hydrogen gas, activated deoxidizing metals, copper, tin, cadmium, Wood's metal alloy (50% bismuth, 25% lead, 12.5% ​​tin, and 12.5% ​​cadmium), etc. In yet another embodiment, the aprotic polar solvent is degassed by freeze-degas-thaw cycles (e.g., at least 1, 2, 3, or more cycles can be used).In one example, the freeze-degass-thaw cycle involves freezing the aprotic polar solvent under liquid nitrogen, applying a vacuum, and then thawing the solvent in warm water. In one embodiment, the aprotic polar solvent is deoxygenated by long-term storage in a steel, glass, or wooden container. In another embodiment, the aprotic polar solvent is sonicated, ultrasonicated, or agitated during deoxygenation.

[0071] Once treated or deoxygenated, the aprotic polar solvent may have less than 0.1 mM dissolved oxygen, preferably less than 0.05 mM dissolved oxygen. Methods known to those skilled in the art may be used to determine the amount of dissolved oxygen in any given aprotic polar solvent (e.g., a dissolved oxygen meter or probe device, such as the dissolved oxygen probe commercially available from Vernier (Beaverton, Oregon, USA) may be used).

[0072] In certain aspects, the formulations disclosed herein can be prepared and / or sealed under an inert gas atmosphere. A common method involves backfilling a primary container sealing system (e.g., a vial) to provide a headspace of inert gas (e.g., nitrogen, argon). A secondary container sealing system (e.g., a sealed foil pouch) can also be sealed under an inert gas environment.

[0073] I. Formulations The formulations of the present invention comprise a therapeutic agent in an aprotic polar solvent system containing at least one ionization-stabilizing excipient and, optionally, one or more additional pharmaceutically acceptable excipients. The therapeutic agent can be dissolved (e.g., completely or partially solubilized) or suspended (completely or partially) in the aprotic polar solvent system.

[0074] In some embodiments, the therapeutic agent is present in an aprotic polar solvent further comprising one or more ionization-stabilizing excipients as described hereinabove, at a concentration as described hereinabove. In other embodiments, the therapeutic agent is present in a "neat" aprotic polar solvent, i.e., an aprotic polar solvent that does not contain a cosolvent, or, if a cosolvent is present, does not contain any cosolvent other than water. In other embodiments, the therapeutic agent is present in a solvent system (i.e., an aprotic polar solvent system) that is a mixture of two or more aprotic polar solvents and has a water content greater than 10% (v / v). One example is a solvent system consisting of a 75 / 25 (v / v) mixture of DMSO and NMP, with a total water content greater than 10% (v / v). However, in some embodiments, a cosolvent can be used, in which case one or more aprotic polar solvents are mixed with the cosolvent. Non-limiting examples of cosolvents include (explicitly excluding water) ethanol, propylene glycol (PG), glycerol, and mixtures thereof. The co-solvent may be present in the formulation in an amount ranging from about 0.1% (w / v) to about 50% (w / v), e.g., about 0.1%, about 0.5%, about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, or about 40% (w / v). In some embodiments, the co-solvent is present in the formulation in an amount ranging from about 10% (w / v) to about 50% (w / v), about 10% (w / v) to about 40% (w / v), about 10% (w / v) to about 30% (w / v), about 10% (w / v) to about 25% (w / v), about 15% (w / v) to about 50% (w / v), about 15% (w / v) to about 40% (w / v), about 15% (w / v) to about 30% (w / v), or about 15% (w / v) to about 25% (w / v).

[0075] Certain preferred, but non-limiting, exemplary formulations of the present invention suitable for use in treating or preventing hypothyroidism or diseases or disorders related or caused thereto comprise levothyroxine at a concentration of about 5 mg / mL or 10 mg / mL, wherein the levothyroxine is dissolved in a solution comprising DMSO and an ionization stabilizing component, such as sulfuric acid, at a concentration of about 13 mM to about 35 mM, e.g., about 26 mM to about 32 mM, and all ranges and concentrations therebetween.

[0076] Furthermore, the formulations of the present invention may contain one or more other excipients in addition to at least one ionizable stabilizing excipient. In some embodiments, the other excipients are selected from sugars, salts, starches, sugar alcohols, antioxidants, chelating agents, and preservatives. Examples of suitable sugar excipients include, but are not limited to, trehalose, glucose, sucrose, etc. Examples of starches suitable as stabilizing excipients include, but are not limited to, hydroxyethyl starch (HES). Examples of sugar alcohols (also referred to as polyols) suitable as stabilizing excipients include, but are not limited to, mannitol and sorbitol. Examples of suitable antioxidants include, but are not limited to, ascorbic acid, cysteine, methionine, monothioglycerol, sodium thiosulfate, sulfite, BHT, BHA, ascorbyl palmitate, propyl gallate, N-acetyl-L-cysteine ​​(NAC), and vitamin E. Examples of suitable chelating agents include, but are not limited to, EDTA, EDTA disodium salt (edetate disodium), tartaric acid and its salts, glycerin, and citric acid and its salts. Examples of suitable inorganic salts include, but are not limited to, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, calcium sulfate, magnesium sulfate, zinc sulfate, and zinc acetate. Examples of suitable preservatives include, but are not limited to, benzyl alcohol, methylparaben, metacresol, propylparaben, and mixtures thereof. Additional formulation components include local anesthetics, such as lidocaine or procaine.In some embodiments, the additional stabilizing excipient is present in an amount of from about 0.01% (w / v) to about 60% (w / v), from about 1% (w / v) to about 50% (w / v), from about 1% (w / v) to about 40% (w / v), from about 1% (w / v) to about 30% (w / v), from about 1% (w / v) to about 20% (w / v), from about 5% (w / v) to about 60% (w / v), from about 5% (w / v) to about 50% (w / v), from about 5% (w / v) to about 40% (w / v), from about 5% (w / v) to about 30% (w / v), from about 5% (w / v) to about 20% (w / v), from about 10% (w / v) to about 60% (w / v), from about 10% (w / v) to about 50% (w / v), or about 10% (w / v). (w / v) to about 40% (w / v), about 10% (w / v) to about 30% (w / v), or about 10% (w / v) to about 20% (w / v). In some embodiments, the additional stabilizing excipient is present in the formulation in an amount of about, at most, or at least 0.01, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60% (w / v).

[0077] II. Therapeutic Agents Therapeutic agents in the context of the present invention include peptide or protein compounds, small molecule drugs, and their pharmaceutically acceptable analogs and / or salts. Those skilled in the art will know which therapeutic agents are suitable for treating a particular disease or condition, and will be able to administer an effective amount of the therapeutic agent in the formulations described herein to treat the disease or condition.

[0078] Non-limiting examples of small molecule drugs (and salts thereof) that may be used in the context of the present invention include levothyroxine, epinephrine, benzodiazepines, catecholamines, "triptans," sumatriptan, novantrone, chemotherapeutic small molecules (e.g., mitoxantrone), corticosteroid small molecules (e.g., methylprednisolone, betamethasone dipropionate), immunosuppressive small molecules (e.g., azathioprine, cladribine, cyclophosphamide monohydrate, methotrexate), anti-inflammatory small molecules (e.g., salicylic acid, acetylsalicylic acid, lisofylline, diflunisal, choline magnesium trisalicylate, salicylate, benorylate, flufenamic acid, mefenamic acid, meclofenamic acid, triflumic acid, acid), diclofenac, fenclofenac, alclofenac, fentiazac, ibuprofen, flurbiprofen, ketoprofen, naproxen, fenoprofen, fenbufen, suprofen, indoprofen, tiaprofenic acid, benoxaprofen, pirprofen, tolmetin, zomepirac, clopinac, indomethacin, sulindac, phenylbutazone, oxyphenbutazone, azapropazone, feprazone, piroxicam, isoxicam), small molecules used to treat neurological disorders (e.g., cimetidine, ranitidine, famotidine, nizatidine, tacrine, metrifonate, rivastigmine, selegiline, imipramine, fluoxetine, olanzapine, sertindole, lisopentidine ... periperidone, valproate semisodium, gabapentin, carbamazepine, topiramate, phenytoin), small molecules used to treat cancer (e.g., vincristine, vinblastine, paclitaxel, docetaxel, cisplatin, irinotecan, topotecan, gemcitabine, temozolomide, imatinib, bortezomib), statins (e.g., atorvastatin, amlodipine, rosuvastatin, sitagliptin, simvastatin, fluvastatin, pitavastatin, lovastatin, pravastatin, simvastatin) and other taxane derivatives, small molecules used to treat tuberculosis (e.g., rifampicin), small molecule antifungals (e.g., fluconazole), small molecule anxiolytics and small molecule anticonvulsants (e.g.,Examples of suitable small molecule drugs include, but are not limited to, small molecule anticholinergics (e.g., lorazepam), small molecule anticholinergics (e.g., atropine), small molecule beta-agonists (e.g., albuterol sulfate), small molecule mast cell stabilizers and small molecule drugs used to treat allergies (e.g., cromolyn sodium), small molecule anesthetics and small molecule antiarrhythmics (e.g., lidocaine), small molecule antibiotics (e.g., tobramycin, ciprofloxacin), small molecule antimigraine drugs (e.g., sumatriptan), and small molecule antihistamines (e.g., diphenhydramine). In a preferred embodiment, the small molecule is levothyroxine. Further suitable examples of such small molecule drugs (and salts thereof) that can be advantageously used in the compositions and methods of the present invention will be known to those skilled in the art based on the information provided herein and information readily available in the art.

[0079] Non-limiting examples of peptides and proteins (and salts thereof) that may be used in the context of the present invention include, but are not limited to, glucagon, pramlintide, insulin, leuprolide, luteinizing hormone-releasing hormone (LHRH) agonists, adrenocorticotropic hormone (ACTH), leuprolide, hirudin, parathyroid hormone (PTH), amylin, angiotensin(1-7), botulinum toxin, hematide, amyloid peptides, gastric inhibitory peptides, antibodies (which may be monoclonal or polyclonal) or fragments thereof, immunogenic peptides (e.g., peptides or peptide complexes derived from viruses, bacteria, or prokaryotic or eukaryotic organisms or cells thereof), insulin-like growth factors, growth hormone-releasing factors, antibacterial factors, glatiramer, glucagon-like peptide-1 (GLP-1), GLP-1 agonists, exenatide, analogs thereof, amylin analogs (pramlintide), and mixtures thereof. In some preferred aspects, the therapeutic agent is glucagon, insulin, and / or pramlintide. Further suitable examples of such peptides, proteins, peptide conjugates, and derivatives thereof that can be advantageously used in the compositions and methods of the present invention will be known to those of skill in the art based on the information provided herein and information readily available in the art.

[0080] The aforementioned small molecule drugs, peptides, and proteins are all well known and commercially available from various manufacturers and suppliers. Furthermore, the amount of small molecule drugs, peptides, and proteins in the dosage forms provided by the present invention can vary depending on currently tolerated amounts, the needs of the subject / patient (e.g., age, health status, weight, nature and severity of symptoms), etc.; such amounts can be easily determined by those skilled in the art of pharmacy and pharmacology based on readily available information.

[0081] Therapeutic agents provided by manufacturers or commercial sources are generally provided in powder form for dissolution in the formulations described herein. Many known techniques can be used to form powders for dissolution.

[0082] Small molecule drugs, peptides, and proteins ("active pharmaceutical ingredients" or "APIs," respectively) can be incorporated into the stable formulations of the invention at any suitable dosage. Generally, the API (or, in embodiments including two or more APIs, each API) is present in the formulation in an amount ranging from about 0.1 μg / mL up to the solubility limit of the API. In certain such embodiments, dosages range from about 0.1 μg / mL to about 500 mg / mL, or up to about 1 mg / mL, about 2.5 mg / mL, about 5 mg / mL, about 7.5 mg / mL, about 10 mg / mL, about 15 mg / mL, about 20 mg / mL, about 25 mg / mL, about 50 mg / mL, about 75 mg / mL, about 100 mg / mL, about 150 mg / mL, about 200 mg / mL, about 250 mg / mL, about 300 mg / mL, about 350 mg / mL, about 400 mg / mL, about 450 mg / mL or about 500 mg / mL, and all dosages between the endpoints of each range described herein. In some embodiments, the small molecule API is levothyroxine, which is present in the formulation in an amount ranging from about 2 mg / mL to about 40 mg / mL, advantageously about 5 mg / mL, about 10 mg / mL, about 15 mg / mL, about 20 mg / mL, or about 40 mg / mL. In other embodiments, levothyroxine is present in the formulation in an amount ranging from about 3 mg / mL to about 20 mg / mL, preferably about 5 mg / mL or 10 mg / mL. For subcutaneous or intramuscular injection into humans in some embodiments of the present invention, the formulation is preferably introduced into a subject, e.g., a human or veterinary animal, in a volume sufficient to deliver about 500 μg to about 1500 μg of levothyroxine, and all amounts within that range. In certain such embodiments, levothyroxine is injected into a subject in a volume suitable to deliver about 600 μg, about 1200 μg, or about 1500 μg of levothyroxine per injection. Again, it will be readily apparent to one of ordinary skill in the art that dosages can vary depending on the API used and the disease, disorder, or condition being treated, based on the information provided herein and information readily available in the relevant art.

[0083] In some embodiments, the formulations of the present invention further comprise an antioxidant. In other embodiments, the formulations further comprise a chelating agent. In still other embodiments, the formulations of the present invention further comprise a preservative, a sugar (e.g., a mono-, di-, or polysaccharide, such as trehalose dihydrate), a sugar alcohol (e.g., mannitol, xylitol, or erythritol), a polyol, a surfactant, and / or a salt.

[0084] III. Treatment method In another aspect, the present invention provides a method for treating or preventing a disease, condition, or disorder by administering to a subject a therapeutic agent for treating or preventing the disease, condition, or disorder in a stable formulation described herein in an amount effective to treat, alleviate, ameliorate, or prevent the disease, condition, or disorder. The therapeutic agents of the present invention can be administered intracutaneously, preferably subcutaneously or intradermally, most preferably subcutaneously, in preventing, diagnosing, alleviating, treating, or curing diseases or physical disorders in humans and veterinary animals.

[0085] In some embodiments, the therapeutic method of the present invention comprises administering a hypothyroidism therapeutic agent, preferably levothyroxine, to a subject with hypothyroidism or a disease or disorder associated therewith in an amount effective to treat the hypothyroidism or a disease or disorder associated therewith, thereby treating the hypothyroidism or a disease or disorder associated therewith. The compositions and methods of the present invention are advantageously used to treat hypothyroidism regardless of the etiology of the hypothyroidism, i.e., regardless of whether the hypothyroidism is caused by a primary or secondary cause. Any condition that affects the thyroid gland and results in low levels of thyroid hormones is considered a primary cause of hypothyroidism. Meanwhile, a secondary cause is any condition, disorder, or injury that causes the pituitary gland to malfunction and fail to secrete thyroid-stimulating hormone (TSH), which signals the thyroid gland to secrete more thyroid hormones to overcome the imbalance characteristic of hypothyroidism. Such diseases or disorders accompanied by, associated with, or caused by hypothyroidism include, but are not limited to, thyroiditis, congenital hypothyroidism, autoimmune hypothyroidism (e.g., Hashimoto's thyroiditis), removal of the thyroid gland by surgical, radiological, or chemical means (such as removal in the treatment of hyperthyroidism or its effects Graves' disease and thyroid eye disease), iodine deficiency, myxedema, myxedema coma / crisis, postpartum thyroiditis, and certain viral illnesses. Patients with hypothyroidism may experience many symptoms, not all of which are associated with every case of hypothyroidism. Such symptoms may include, for example, fatigue, peripheral neuropathy (especially experiencing numbness or tingling in the hands and / or fingers), weight gain, development of goiter, fibromyalgia, body pain such as muscle weakness and joint pain, high cholesterol, depression, hypothermia or increased sensitivity to cold temperatures, dry / rough skin and hair, hair loss, physical changes in facial appearance (e.g., drooping eyelids or puffy eyes / face), and cognitive or memory problems (often described as "brain fog").By treating and / or preventing hypothyroidism, the levothyroxine-containing compositions and methods of the present invention result in the improvement or reversal of thyroid hormone imbalance in a subject, which in turn results in the alleviation or reduction of the above-mentioned symptoms. In certain non-limiting exemplary embodiments, as described in the Examples below, the use of the formulations of the present invention administered subcutaneously to a subject can overcome the limitations of traditional daily oral (per oral administration or "PO") administration of solid forms of levothyroxine, such as tablets, by allowing for weekly, bimonthly, or monthly administration of levothyroxine to a subject, thereby improving patient experience and compliance with treatment regimens designed and prescribed by the treating physician or other healthcare provider.

[0086] In some embodiments, the therapeutic method of the present invention comprises treating hypoglycemia by administering to a subject with hypoglycemia a hypoglycemic therapeutic agent in a storage-stable sustained-release formulation described herein in an amount effective to treat hypoglycemia. In some embodiments, the subject is administered a storage-stable sustained-release formulation comprising glucagon in a manner that results in the release of glucagon from the administration site into the animal's bloodstream or tissue for a prolonged period of time compared to an immediate-release formulation comprising glucagon (i.e., "sustained release"). In such aspects, the disease, condition, or disorder treated with the stable formulation of the present invention is a diabetic condition. Examples of diabetic conditions include, but are not limited to, type 1 diabetes, type 2 diabetes, gestational diabetes, prediabetes, hyperglycemia, hypoglycemia, and metabolic syndrome. In some embodiments, the disease, condition, or disorder is hypoglycemia, including but not limited to diabetes-related hypoglycemia, exercise-induced hypoglycemia, and post-bariatric surgery hypoglycemia, or other types of hypoglycemia described herein and known to those of skill in the art (see, e.g., U.S. Patent Nos. 9,649,364, 10,485,850, and 11,020,403; the disclosures of which are incorporated herein by reference in their entireties). In some embodiments, the disease, condition, or disorder is diabetes.

[0087] In some embodiments, the therapeutic methods of the present invention comprise treating diabetes by administering to a subject with diabetes a therapeutic agent in a stable formulation described herein in an amount effective to treat diabetes. In some embodiments, the subject is administered a stable formulation comprising insulin. In some embodiments, the subject is administered a stable formulation comprising pramlintide. In some embodiments, the subject is administered a stable formulation comprising insulin and pramlintide. In some embodiments, the subject is administered a stable formulation comprising exenatide. In some embodiments, the subject is administered a stable formulation comprising glucagon and exenatide.

[0088] In certain aspects, the epinephrine-containing formulations of the present invention can be administered to subjects at risk of or suspected of anaphylaxis. Epinephrine is indicated as an emergency treatment for Type I allergic reactions, which can arise from a variety of sources, including, but not limited to, food, drug and / or other allergens, allergen immunotherapy, diagnostic test substances, insect stings, and idiopathic or exercise-induced anaphylaxis.

[0089] Dosages of the small molecule or peptide drugs described herein for treating a disease, condition, or disorder (e.g., hypothyroidism, diabetic conditions, hypoglycemia, or anaphylaxis) are as described herein, according to dosage and schedule plans implemented by those skilled in the art. General guidance regarding appropriate dosages of all pharmacological agents used in the methods of the present invention is provided in Goodman and Gilman's *The Pharmacological Basis of Therapeutics*, 11th ed., 2006, supra, and the Physicians' Desk Reference (PDR), e.g., 65th ed. (2011) or 66th ed. (2012), PDR Network, LLC, each of which is incorporated herein by reference. Appropriate dosages of small molecule or peptide drugs for treating a disease, condition, or disorder described herein will vary depending on several factors, including the formulation of the composition, patient response, the severity of the condition, the subject's weight, and the judgment of the prescribing physician. Effective dosages of the described formulations deliver a medically effective amount of the small molecule or peptide drug. Dosages can be titrated (i.e., increased or decreased over time) according to the needs of an individual patient or according to the judgment of a medical professional. Thus, determining an effective amount or dose of a small molecule or peptide drug, and thus an appropriate amount or volume of a therapeutic formulation of the invention to be administered to a subject, is within the capabilities of those skilled in the art, especially in light of the detailed disclosure provided herein.

[0090] The formulations of the present invention can be used for parenteral administration, including but not limited to subcutaneous, intradermal, intramuscular, intranasal, oral, transdermal, or intravenous administration (e.g., by injection or infusion).In some embodiments, the formulation is administered subcutaneously.The formulation can also be delivered transdermally, for example, by topically applying the composition to the skin (e.g., by spreading the composition on the skin or by loading the composition into a skin patch and applying the skin patch to the skin).

[0091] The formulations of the present disclosure can be administered by infusion or injection using any suitable device. For example, the formulations of the present disclosure can be contained in a syringe (e.g., a pre-filled syringe), a pen injection device, an automatic injection device, or a pump device. In some embodiments, the injection device is a multi-dose injection pump device or a multi-dose automatic injection device. The formulation is present in the device in such a manner that it can easily flow out of the needle to deliver the peptide drug when the injection device, e.g., an automatic injector, is activated. Suitable pen / automatic injection devices include, but are not limited to, pen / automatic injection devices manufactured by Becton-Dickinson, Swedish Healthcare Limited (SHL Group), YpsoMed Ag, etc. Suitable pump devices include, but are not limited to, pump devices manufactured by Tandem Diabetes Care, Inc., Delsys Pharmaceuticals, etc.

[0092] In some embodiments, the formulations of the invention are provided ready to administer in vials, cartridges, or pre-filled syringes.

[0093] In further embodiments, the formulations provided by the present invention can be used in certain diagnostic procedures. In certain such embodiments, the glucagon-containing formulations of the present invention can be administered to a mammal, such as a human or veterinary animal, prior to, as an adjunct to, as part of, or in combination with one or more diagnostic procedures, thereby providing a method of diagnosing a disease or disorder in a patient suffering from or susceptible to the disease or disorder. Non-limiting examples of such diagnostic procedures in which the glucagon-containing formulations of the present invention may be suitably used include methods of diagnosing Alzheimer's disease (see U.S. Pat. No. 4,727,041, which is incorporated herein by reference in its entirety) and growth hormone deficiency (see U.S. Pat. No. 5,065,747; see also Boguszewski, CL, Endocrine 57: 361-363 (2017), and Yuen, KCJ, ISRN Endocrinology, vol. 211, Article ID 608056, pp. 1-6 (2011), doi:10.5402 / 2011 / 608056; the disclosures of all of which are incorporated herein by reference in their entirety). Further examples of such uses are in certain radiological diagnostic procedures, particularly those used in the diagnosis of gastrointestinal disease conditions (non-limiting examples of which include intestinal obstruction, appendicitis, Barrett's esophagus, celiac disease, cancer, cirrhosis, Crohn's disease, diverticulitis, diverticulosis, ulcers, gallstones, gastric prolapse, gastritis, gastroesophageal reflux disease, hepatitis (A / B / C), hiatal hernia, inflammatory bowel disorder, hernia, irritable bowel syndrome, pancreatitis, perianal cleft, ulcerative colitis, etc.), in adult patients. during radiological examinations of the gastrointestinal system to temporarily inhibit the movement of organs and connective tissues of the gastrointestinal tract (see, e.g., the product label for glucagon lyophilized (NDC code 63323-185-03), available at https: / / dailymed.nlm.nih.gov / dailymed / drugInfo.cfm?setid=8c8acad6-44cc-43aa-966b-027e053be8f5); Glucagon in Gastroenterology(See also J. Picazo, ed., Lancaster, England: MTP Press Ltd. (1979), especially Chapters 3-7, pp. 39-120; the disclosure of which is incorporated herein by reference.) In such diagnostic methods, the glucagon-containing formulations of the present invention are administered to a patient suffering from or susceptible to a disorder by any suitable method for introducing such a formulation into the patient's body, such as those described herein, e.g., intravenously at a dose of about 0.2 mg to about 0.75 mg about 1 to 10 minutes before a diagnostic test (e.g., a radiological procedure), or intramuscularly or transdermally at a dose of about 1 mg to about 2 mg about 5 to 15 minutes before a diagnostic test (e.g., a radiological procedure). Other suitable therapeutic and diagnostic methods of use of the formulations of the present invention will be readily known to a physician or pharmacist of ordinary skill based on the disclosure contained herein in light of information available in the art.

[0094] IV. Kits / Containers Kits are also contemplated as being provided by certain embodiments of the present invention. For example, the formulations of the present invention can be included in a kit, which can include a container. In one aspect, the formulation can be included in a container ready for administration to a subject, or incorporated into a device configured for administration to a subject, for example, without the need to reconstitute or dilute the formulation. That is, the formulation to be administered can be stored in the container and immediately used as needed. In some embodiments, the container can be a device. The device can be a syringe (e.g., a pre-filled syringe), a pen-type syringe, an auto-injector, a device capable of pumping or administering the formulation (e.g., an automatic or non-automatic external pump (e.g., a patch pump or a pump requiring an external infusion set), an implantable pump, etc.), or an infusion bag. Suitable pen-type / auto-injectors include, but are not limited to, pen-type / auto-injectors manufactured by Becton-Dickinson, Swedish Healthcare Limited (SHL Group), YpsoMed Ag, etc. Suitable pump devices include, but are not limited to, pump devices manufactured by Tandem Diabetes Care, Inc., Delsys Pharmaceuticals, etc. Suitable infusion sets include, but are not limited to, those manufactured / distributed / sold by Tandem Diabetes Care, Inc., Medtronic, Disetronic, YpsoMed Ag, Unomedical A / S, etc. Kits of the present invention can also include one or more additional components, including, but not limited to, instructions for use for the kit and / or its components, one or more additional containers or compartments for holding the components of the kit, multiple containers or devices containing the formulations of the present invention, etc. [Example]

[0095] Some aspects of the present disclosure will be described in more detail with reference to specific examples. The following examples are provided for illustrative purposes and are not intended to limit the present invention in any way. For example, those skilled in the art will readily recognize various non-critical parameters that can be changed or modified without undue experimentation to achieve essentially the same results.

[0096] Example 1: Concentration Effect on the Pharmacokinetics of Liquid Levothyroxine-Containing Formulations Formulation development conducted by the present inventors resulted in the production of stable liquid levothyroxine-containing formulations prepared by solubilizing levothyroxine sodium in acidified dimethyl sulfoxide (DMSO). These formulation studies are described in detail in U.S. Application No. 63 / 380,090, entitled "Stable Levothyroxine Formulations in Aprotic Polar Solvents," filed on even date herewith, and incorporated herein by reference in its entirety. Briefly, an exemplary such formulation was prepared having the following composition: 10 mg / mL levothyroxine sodium; 5.53% (w / v) trehalose dihydrate; 2.9% (w / v) mannitol; 26-28 mM sulfuric acid (from a 1.0 N stock solution) and DMSO. Preparation of these solutions demonstrated that the formulation did not freeze when stored under refrigerated conditions, and real-time accelerated stability testing, completed after the filing date of this application, indicates that the formulation is expected to achieve at least two years of refrigerated storage stability (using a stability specification of 95% API content). The total water content of this formulation was approximately 5% when prepared using 1.0 N H2SO4. The water content of this formulation is almost entirely due to added sulfuric acid (with a negligible contribution from trehalose dihydrate), resulting in a water content of approximately 5% (w / w) at 26 mM (from a 1.0 N (0.5 M) stock solution). When prepared using concentrated acid (e.g., 10 N), the total water content of the formulation can be reduced to approximately 1% without significantly affecting storage stability. Another exemplary formulation was prepared at a concentration of 5 mg / mL levothyroxine in DMSO that had first been acidified with approximately 13-15 mM sulfuric acid. These formulations were then used in preclinical studies of levothyroxine pharmacokinetics in laboratory animals.

[0097] These studies were conducted in Goettingen minipigs (4-6 month old males) obtained from Marshall Bioresources (Syracuse, NY). Nine levothyroxine formulations were prepared, all containing 10 mg / mL levothyroxine in acidified DMSO, using the XeriSol™ formulation platform (Xeris Pharmaceuticals, Inc.; Chicago, IL) as previously described for other active pharmaceutical ingredients (see, e.g., U.S. Pat. Nos. 9,649,364, 10,485,850, and 11,020,403; the disclosures of which are incorporated herein by reference in their entireties). Additionally, to examine the impact of including sustained-release excipients in the formulation on pharmacokinetics, some of these formulations were formulated with specific concentrations of poly(lactic-co-glycolic acid) (PLGA) of various molecular weights and concentrations; PLGA is known to be useful in XeriSol formulations for producing sustained-release formulations of various therapeutic compounds (see, e.g., U.S. Patent Publication No. US 2021 / 0401945 A1, which is incorporated herein by reference in its entirety). The formulations prepared are shown in Table 1 below.

[0098] Table 1: Test formulations TIFF2025536328000001.tif94159

[0099] Göttingen minipigs (n=12) were randomly assigned based on body weight to treatment groups 1, 2, and 3 according to Table 2. Three groups of four minipigs each received a single dose of one of the levothyroxine formulations listed in Table 2. There was a minimum washout period of 21 days, after which the animals were re-administered with the next set of formulations. After washout of each dose, animals were transferred to subsequent groups as follows: Group 1 → Group 4 → Group 7; Group 2 → Group 5 → Group 8; Group 3 → Group 6 → Group 9. All formulations were administered subcutaneously at a fixed dose of 10 mg per animal. Blood samples were collected to measure plasma levothyroxine concentrations at the following time points: pre-dose (baseline) and 0.083, 0.25, 0.5, 1, 2, 4, 6, 8, 24, 48, 72, 96, 120, 144, 192, 240, 288, and 366 hours post-dose.

[0100] A bioanalytical method for measuring levothyroxine (L-thyroxine) concentrations in miniature pig plasma was developed by Pyxant Labs Inc. The method was qualified over a range of 2.00–4000 ng / mL. The method utilizes an alternative matrix approach for L-thyroxine quantification; 5% bovine serum albumin (BSA) in water is used because L-thyroxine is endogenous. Samples were prepared by protein precipitation extraction. Extracts were analyzed by liquid chromatography / tandem mass spectrometry (LC-MS / MS) in positive ionization mode to separate levothyroxine and thyroxine-formed ... 13 The analysis was carried out under conditions optimized for the detection of positive ions of C6 (internal standard).

[0101] Noncompartmental pharmacokinetic analyses were performed on each animal's baseline-adjusted levothyroxine levels using Phoenix 64 software version 8.2.0.4383 (Certara, Inc.; Princeton, NJ). Pharmacokinetic parameters obtained included Cmax, Tmax, AUClast, and AUC. Values ​​for λz, t1 / 2, and AUC∞ were not determined due to the high variability of plasma levels during the terminal phase. The results of each of these analyses are shown in Figures 1–7.

[0102] All animals demonstrated quantifiable increases in baseline-adjusted plasma levothyroxine concentrations after SC administration of the test article (Figure 1). The plasma concentration-time curve for XeriSol™ levothyroxine (XS-1) was characterized by gradual absorption, reaching Cmax at a median of 16 hours (range: 8-24 hours) (Figures 1 and 3). Xerisol™ PLGA levothyroxine formulations XS-3, XS-8, and XS-9 reached Cmax more quickly, at a median of 8 hours (range: 8-24 hours) (Figures 1 and 3); whereas, PLGA levothyroxine formulations XS-2, XS-4, XS-5, XS-6, and XS-7 reached Cmax more slowly, at a median of 24 hours (range: 24-24 hours) (Figures 1 and 3). These differences are not considered significant due to the small number of animals in each group (n = 4) and overlapping Tmax ranges (Figure 2) across all groups.

[0103] As shown in Figure 3, mean ± SD baseline-adjusted levothyroxine Cmax was highest for Xerisol™ levothyroxine (XS-1) (1784.2 ± 527.1 ng / mL) and XeriSol™ levothyroxine PLGA formulations XS-2 (1750.1 ± 389.7) and XS-9 (1789.3 ± 386.1 ng / mL). The Cmax of XS-8 was approximately 10% lower than that of XS-1, and the remaining formulations had Cmax 27% to 50% lower than that of XS-1, in the following order: XS-7 (1305.9 ± 305.9 ng / mL) > XS-4 (1156.9 ± 69.8 ng / mL) > XS-3 (1130.3 ± 504.2 ng / mL) > XS-5 (1011.2 ± 227.2 ng / mL) > XS-6 (896.6 ± 166.2 ng / mL).

[0104] From the results shown in Figure 4, AUClast (hr * The mean ± SD baseline-adjusted plasma levothyroxine exposure, as determined by ng / mL, was demonstrated to be highest for Xerisol™ levothyroxine (XS-1) (96,461.3 ± 17,426.8), followed by XS-2 (83,732.2 ± 36,156.9). Five formulations had AUClasts 20% to 32% lower than XS-1, in the following order: XS-7, XS-9, XS-5, XS-4, and XS-8. Formulations XS-6 (56,709.6 ± 3976.1) and XS-3 (52,934.8 ± 6383.5) had the lowest exposure levels, 41% and 45%, respectively, compared to formulation XS-1.

[0105] As shown in Figure 5, mean ± SD baseline-adjusted plasma levothyroxine fractional exposure (AUC144-336) was higher for all PLGA-containing formulations compared to XS-1. Formulations XS-2 (3655.1 ± 1903.9), XS-3 (3075.3 ± 1182.2), and XS-8 (2721.3 ± 3325.6) had AUC144-336 12% to 50% greater than XS-1 (2435.8 ± 2710.5). Formulations XS-4 (4237.9 ± 1266.5), XS-7 (4938.8 ± 2515.6), and XS-9 (4472.6 ± 4503.2) had AUC144-336 74% to 103% greater than XS-1. Formulations XS-5 (8467.0 ± 9782.1) and XS-6 (7161.6 ± 4582.0) had fractional exposures 194% to 248% greater than that of formulation XS-1.

[0106] These results are compared in more detail in Table 2 below, which summarizes all of the measured and calculated pharmacokinetic parameters for each formulation.

[0107] Table 2. Baseline-adjusted plasma levothyroxine pharmacokinetic parameters following subcutaneous administration of XeriSol™ levothyroxine and XeriSol / PLGA levothyroxine formulations in Goettingen minipigs TIFF2025536328000002.tif162166

[0108] The PLGA-containing formulations were expected to have lower maximum concentrations because drug release was expected to slow as the PLGA degraded. A significantly lower Cmax was observed for formulations XS-3 through XS-7. Longer Tmax was also expected, but was not observed to differ substantially between formulations. Exposure was 10% to 45% lower for all PLGA-containing formulations compared to XeriSol™ levothyroxine (XS-1) without PLGA. These results suggest that absorption of the PLGA-containing test articles was incomplete or very slow. The fractional exposure AUC144-336 shown in Table 2 and Figure 5 demonstrates that the PLGA-containing formulations had greater fractional exposure over 144 hours to 336 hours compared to XS-1, suggesting that the PLGA-containing formulations may be absorbed slowly and sustainedly.

[0109] We next wished to examine the pharmacokinetics of two Xerisol™ levothyroxine formulations containing 5 mg / mL ("XP-8121-5") or 10 mg / mL ("XP-8121-10") levothyroxine sodium. These formulations were prepared using the acidified DMSO solution approach described above, except that an ionizable stabilizing excipient (in this example, sulfuric acid) was added to the formulation at a molar ratio of approximately 2.5:1 relative to the API content in the DMSO-based solvent system. Minipigs were administered these formulations as described in the previous section, and pharmacokinetic parameters were measured as described above. The results are shown in Figures 6 and 7. In both baseline-uncorrected (Figure 6) and baseline-corrected (Figure 7) analyses, the 5 mg / mL and 10 mg / mL formulations had similar Tmax (within approximately 2 hours) whether assessed by linear plots (Figures 6A and 7A) or semi-logarithmic plots (Figures 6B and 7B). Interestingly, the Cmax of the 5 mg / mL formulation was observed to be higher than that of the 10 mg / mL formulation in all analyses, but injection of the 10 mg / mL formulation resulted in sustained levothyroxine plasma concentrations for a longer period compared to the 5 mg / mL formulation. These results suggest a concentration effect on the release kinetics of levothyroxine from the injection site into the bloodstream—levothyroxine administered from a 5 mg / mL solution was released into the bloodstream more rapidly and reached its Cmax earlier than levothyroxine administered from a 10 mg / mL solution, but the latter showed elevated blood concentrations of levothyroxine for a longer period after injection than the former.

[0110] Individual and summary values ​​of baseline-unadjusted and baseline-adjusted pharmacokinetic parameters determined as above are shown in Tables 3 and 4, respectively.

[0111] Table 3. Individual and summary values ​​of baseline unadjusted plasma levothyroxine pharmacokinetic parameters by treatment TIFF2025536328000003.tif225141

[0112] Table 4. Individual and summary baseline-adjusted plasma levothyroxine pharmacokinetic parameters by treatment TIFF2025536328000004.tif232139

[0113] Taken together, these results indicate that there is a dose- or concentration-dependent effect on the release of levothyroxine from a subcutaneous injection site into the blood. Specifically, for a given injection volume, a higher concentration of levothyroxine in the formulation used for injection provided a means for longer-lasting concentrations after reaching therapeutic levels of levothyroxine in plasma compared to lower-concentration formulations (e.g., a 10 mg / mL levothyroxine formulation demonstrated longer-lasting elevated plasma levels of levothyroxine compared to those seen with a 5 mg / mL formulation). Based on these results, the use of such formulations that provide more sustained, long-term delivery of levothyroxine should enable subjects being treated for hypothyroidism with this drug to have their levothyroxine administered less frequently than daily dosing (as currently achieved using oral administration of solid dosage forms containing levothyroxine, such as Synthroid®) to less frequent subcutaneous dosing (e.g., weekly, or perhaps once every two weeks or even longer, using higher concentrations of levothyroxine, e.g., 15 mg / mL, 20 mg / mL, 40 mg / mL, etc., up to the solubility limit of the API in aprotic polar solvent systems).

[0114] Example 2: Concentration effect on the pharmacokinetics of liquid diazepam-containing formulations To further explore the concentration effect on pharmacokinetics observed in Example 1, diazepam, another compound with low solubility in aqueous media, was formulated at concentrations of 50 mg / mL and 100 mg / mL in XeriSol™ solution of acidified DMSO, as described in Example 1 for levothyroxine. These formulations were then evaluated for pharmacokinetics in minipigs after SC administration, as described above in Example 1 for levothyroxine (Xeris Pharmaceuticals, Inc. Study 12412). The results of these studies are shown in Figure 8.

[0115] The pharmacokinetics of the higher-concentration (100 mg / mL) diazepam formulation were characterized by a lower mean (SD) Cmax (296 ng / mL (182 ng / mL) vs. 412 ng / mL (454 ng / mL)) and a longer median (range) Tmax (240 minutes (60-240 minutes) vs. 120 minutes (15-120 minutes)) compared with the lower-concentration (50 mg / mL) diazepam formulation. Mean (SD) diazepam exposure (AUClast) was similar between the 100 mg / mL (102,752 ng*min / mL (39,313 ng*min / mL)) and 50 mg / mL (99,775 ng*min / mL (54,804 ng*min / mL)) formulations.

[0116] Thus, as observed for levothyroxine in Example 1, liquid diazepam-containing injectable formulations exhibit dose- or concentration-dependent effects on the release of diazepam from a subcutaneous injection site into the blood. Specifically, for a given injection volume, the higher diazepam concentration in the formulation used for injection provided a means for rapidly reaching therapeutic levels of diazepam in the plasma followed by sustained concentrations and slower clearance kinetics compared to lower-concentration formulations (e.g., a 100 mg / mL diazepam formulation exhibited longer-lasting release kinetics compared to a 50 mg / mL formulation). The use of such formulations, which deliver diazepam more sustained over time, should enable the administration frequency of diazepam to subjects being treated with this drug to treat diseases or physical disorders readily treatable with benzodiazepines (e.g., diazepam), such as anxiety, muscle spasms, and seizures, to be reduced from daily oral administration to less frequent (e.g., weekly) subcutaneous administration.

[0117] Example 3: Concentration effect on the pharmacokinetics of liquid tamsulosin-containing formulations Another active pharmaceutical ingredient with similar solubility characteristics to levothyroxine and diazepam is tamsulosin, a drug currently administered as a once-daily oral tablet for the treatment of certain genitourinary diseases / disorders in men, particularly benign prostatic hyperplasia and kidney stones. Tamsulosin has good solubility in DMSO (100 mM, >40 mg / ml) and relatively low solubility in aqueous / physiological environments (approximately 10 mM, 4 mg / ml). This drug is typically administered to patients at a daily dose of 0.4 mg, which corresponds to a weekly dose of approximately 3 mg. Therefore, tamsulosin is formulated in XeriSol™ acidified DMSO solution, as described above for levothyroxine and diazepam in Examples 1 and 2, respectively. A 0.1 ml volume of a 30 mg / ml XeriSol™ formulation of tamsulosin is then subcutaneously injected into the patient, thereby administering 3 mg per injection. Such an amount would significantly exceed the solubility limit of tamsulosin in the aqueous subcutaneous environment, and the tamsulosin would largely precipitate, forming a depot for sustained delivery of tamsulosin with pharmacokinetics similar to those described above for levothyroxine and diazepam. Thus, the use of such a formulation that provides more sustained, long-term delivery of tamsulosin should enable subjects receiving treatment with this drug to reduce the frequency of tamsulosin administration from daily oral administration to less frequent (e.g., weekly) subcutaneous administration.

[0118] Example 4: Human pharmacokinetic study using a liquid levothyroxine-containing formulation In another series of studies, the inventors wished to determine whether the pharmacokinetics observed in humans using the XP-8121 levothyroxine-containing formulations of the present invention were similar to those observed in preclinical studies using experimental animals, such as those described in Example 1. These studies were designed for several purposes: (a) to characterize the pharmacokinetics of subcutaneous injections of XP-8121 (injections at doses of 600 μg, 1200 μg, and 1500 μg from a 10 mg / mL levothyroxine formulation described in Example 2 for XP-8121); (b) to evaluate the bioavailability (compared to oral levothyroxine formulations such as Synthroid®) and dose proportionality (600 μg, 1200 μg, and 1500 μg) of XP-8121; and (c) to evaluate the safety and tolerability of XP-8121. In addition, a post-study PK analysis (population PK modeling) was performed to compare steady-state exposure (AUC) between weekly subcutaneous (SC) administration of XP-8121 and daily oral (PO) administration of Synthroid®, and to examine dose conversion from Synthroid® PO to XP-8121 SC.

[0119] The study was designed according to the schematic diagram shown in Figure 9. The study, designated XP-8121-108, examined the pharmacokinetics of plasma levothyroxine in 30 subjects; subjects were divided equally into two groups of 15 and administered either 600 μg of Synthroid® PO or XP-8121 SC on day 0. After a 42-day washout period, subjects received 600 μg of the other form of levothyroxine. After another 42-day washout period, both groups received a subcutaneous injection of 1200 μg of XP-8121. After a short pause in the study for U.S. FDA review of safety and pharmacokinetic data, the study protocol was amended to evaluate doses of levothyroxine greater than 1200 μg. Therefore, in the final portion of the study, 30 additional subjects received a subcutaneous injection of 1500 μg of levothyroxine in the XP-8121 formulation of the present invention. Pharmacokinetic parameters were measured and determined as described in Figure 1 and calculated as described for the preclinical pharmacokinetic analysis in Example 1. The results of these studies are shown in Figures 10-14.

[0120] Figure 10 shows mean baseline-adjusted plasma levothyroxine concentrations over time plotted as a linear plot (Figure 10A) and a logarithmic plot (Figure 10B) for various doses (600 μg, 1200 μg, 1500 μg) of XP-8121 injected subcutaneously (SC) and 600 μg of Synthroid® administered orally (PO). As can be seen in Figures 10A and 10B, Synthroid® PO 600 μg showed a rapid rise in levothyroxine levels followed by a rapid fall, while XP-8121 SC (all doses) showed a gradual rise in levothyroxine levels followed by sustained exposure; this exposure exceeded the levothyroxine levels obtained from Synthroid® PO. Furthermore, once Cmax was reached, plasma T4 levels remained steadily elevated for 4-5 days with XP-8121, in contrast to Synthroid®, which declined quickly. Finally, the Tmax of XP-8121 was also observed to be longer than that of Synthroid® PO.

[0121] Similar results were observed for other pharmacokinetic parameters. As shown in Figure 11A, the median Tmax of XP-8121 (48, 72, and 96 hours for the 600 μg, 1200 μg, and 1500 μg doses, respectively) was greater than that observed for Synthroid® PO (3 hours). The mean half-life (T 1 / 2 ) (177, 112, and 120 hours for the 600 μg, 1200 μg, and 1500 μg doses, respectively) were similar to that observed with Synthroid® PO (144 hours) (FIG. 11B). FIG. 12 shows the mean baseline levothyroxine exposure in subjects treated with SC XP-8121 and PO Synthroid®. The mean Cmax for XP-8121 600 μg was lower than the mean Cmax for Synthroid® PO 600 μg (FIG. 12A). Furthermore, while mean unadjusted levothyroxine AUC values ​​were similar between XP-8121 SC 600 μg and Synthroid® PO 600 μg (data not shown), the mean baseline-adjusted levothyroxine AUC value for XP-8121 SC 600 μg was 35% greater than that for Synthroid® PO 600 μg (Figure 12B). XP-8121 SC also demonstrated a dose-dependent increase in exposure (C (Figure 12A) and AUC (Figure 12B)). Thus, a single dose of SC XP-8121 had a significantly lower C and equivalent or greater exposure, as measured by AUC, compared with Synthroid® PO.

[0122] To further examine the dose-proportionality of baseline-adjusted XP-8121, mean baseline-adjusted Cmax normalized to levothyroxine dose was plotted on a linear scale (Figure 13A) or a logarithmic scale (Figure 13B). These parameters were calculated using concentrations from matched PK time points in Part 1 and Part 2 of the study (PK population) shown in Figure 9. The results shown in Figure 13 demonstrate that the baseline-adjusted Cmax of XP-8121 was proportional to dose. Similarly, the baseline-adjusted AUClast of XP-8121 was also found to be proportional to dose when plotted on either a linear scale (Figure 14A) or a logarithmic scale (Figure 14B).

[0123] Combined with the results of the previous examples, these results demonstrate that storage-stable, ready-to-use liquid levothyroxine-containing injectable formulations can be produced as described herein, and that these formulations, when subcutaneously introduced into a subject (such as a human, as in this Example 4), can promote an increase in plasma levothyroxine levels in the subject with slower release kinetics (i.e., sustained-release pharmacokinetics) than those observed with oral immediate-release solid formulations of levothyroxine, such as Synthroid®. More specifically, the results of this Example 3 demonstrate that Synthroid® PO 600 μg exhibited a rapid rise in levothyroxine levels followed by a rapid fall, whereas XP-8121 SC (all doses) exhibited a gradual rise in levothyroxine levels followed by sustained exposure. Furthermore, XP-8121 SC (all doses) had a longer Tmax than Synthroid® PO 600 μg. Although plasma levothyroxine half-life was similar across all groups, the mean Cmax of XP-8121 600 μg was less than half (47%) of that of Synthroid® PO 600 μg. Furthermore, the increase in XP-8121 SC levothyroxine exposure (Cmax and AUClast) was confirmed to be dose-proportional. Thus, as seen in the animal studies in Examples 1 and 2 above, there was a dose- or concentration-dependent effect on the release of levothyroxine from the subcutaneous injection site into the blood of human subjects. Specifically, subcutaneous injection of higher doses of levothyroxine into humans provided a means for sustained concentrations and slower clearance kinetics after reaching therapeutic levels of levothyroxine in plasma compared to injection of lower doses of levothyroxine (e.g., injection of 1500 μg of levothyroxine exhibited longer-lasting release kinetics compared to that seen with injection of a 1200 μg dose of levothyroxine, which in turn exhibited longer-lasting release kinetics compared to that seen with injection of a 600 μg dose of levothyroxine formulation, which in turn exhibited longer-lasting release kinetics compared to that seen with oral administration of a 600 μg dose of levothyroxine (Synthroid®)).Based on these results, the use of such formulations that provide more sustained, long-term delivery of levothyroxine should enable subjects being treated for hypothyroidism with this drug to have their levothyroxine administered less frequently (e.g., weekly) subcutaneously from daily administration (currently achieved using oral solid dosage forms containing levothyroxine, e.g., Synthroid®).

[0124] All aspects of the present invention, including the compositions and / or methods disclosed and claimed herein, can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of the present disclosure have been described with reference to certain exemplary embodiments, it will be apparent to those skilled in the art that changes can be made in the compositions and methods described herein, and in the steps or sequence of steps of the methods, without departing from the concept, spirit, and scope of the present disclosure. More specifically, it will be apparent that certain chemically and physiologically related agents may be substituted for the agents described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the invention as defined by the appended claims.

Claims

1. (a) at least one therapeutic agent; (b) at least one ionizable stabilizing excipient; and (c) Aprotic polar solvent system 1. A storage-stable sustained release therapeutic formulation comprising: the at least one therapeutic agent is poorly soluble in an aqueous environment but readily soluble in the aprotic polar solvent system; the formulation is storage stable for at least six months at 2°C to 8°C and, when administered to a patient, results in therapeutic levels of the at least one therapeutic agent in the patient's blood for an extended period of time compared to an immediate release formulation comprising the at least one therapeutic agent; The formulation.

2. 10. The formulation of claim 1, wherein the therapeutic agent is selected from the group consisting of levothyroxine or a salt thereof, a benzodiazepine, and tamsulosin.

3. 3. The formulation of claim 2, wherein the therapeutic agent is levothyroxine free acid or levothyroxine sodium.

4. 3. The formulation of claim 2, wherein the benzodiazepine is diazepam.

5. 2. The formulation of claim 1, wherein the aprotic polar solvent system comprises or is dimethyl sulfoxide (DMSO).

6. 10. The formulation of claim 1, wherein the ionizable stabilizing excipient is an inorganic acid.

7. 7. The formulation of claim 6, wherein the inorganic acid is selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

8. 8. The formulation of claim 7, wherein the inorganic acid is sulfuric acid.

9. 7. The formulation of claim 6, wherein the inorganic acid is present in the formulation at a molar concentration ratio of between 2:1 and 3:1 relative to the concentration of the therapeutic agent in the formulation.

10. 10. The formulation of claim 9, wherein the inorganic acid is present in the formulation at a molar concentration ratio of about 2.5:1 relative to the concentration of the therapeutic agent in the formulation.

11. 4. The formulation of claim 3, comprising levothyroxine sodium in a concentration from about 5 mg / mL and sulfuric acid in a concentration from about 13 mM to about 15 mM.

12. 4. The formulation of claim 3, comprising levothyroxine sodium in a concentration from about 10 mg / mL and sulfuric acid in a concentration from about 26 mM to about 28 mM.

13. 10. The formulation of claim 1, further comprising one or more additional pharmaceutically acceptable excipients.

14. 14. The formulation of claim 13, wherein the one or more additional pharmaceutically acceptable excipients are selected from the group consisting of sugars, sugar alcohols, preservatives, and polymers.

15. 15. The formulation of claim 14, wherein the sugar is trehalose or a salt or hydrate thereof.

16. 16. The formulation of claim 15, wherein the sugar is trehalose dihydrate.

17. 15. The formulation of claim 14, wherein the sugar alcohol is mannitol.

18. 15. The formulation of claim 14, wherein the preservative is benzyl alcohol.

19. 15. The formulation of claim 14, wherein the polymer is poly(lactic-co-glycolic acid) (PLGA).

20. 20. The formulation of claim 19, wherein the PLGA is an ester-terminated PLGA or an acid-terminated PLGA.

21. 10. A method for treating or preventing a disease or disorder in a human or veterinary animal, comprising administering a therapeutically effective amount of the formulation of claim 1 to a human or veterinary animal in need thereof, monitoring the level in the plasma of said human or veterinary animal over time, and repeating the administration of said formulation to said subject as necessary to treat or prevent said disease or disorder in said human or veterinary animal.

22. 22. The method of claim 21, wherein the formulation is introduced into the human or veterinary animal by parenteral administration.

23. 22. The method of claim 21, wherein the parenteral administration is by injection or infusion.

24. 24. The method of claim 23, wherein the injection is subcutaneous, intradermal, or intramuscular.

25. 24. The method of claim 23, wherein the injection is subcutaneous.

26. 24. The method of claim 23, wherein the infusion is accomplished by pump infusion.

27. 27. The method of claim 26, wherein the pump infusion comprises continuous or bolus pump infusion, or a combination thereof.

28. 22. The method of claim 21, wherein the therapeutic agent is selected from the group consisting of levothyroxine or a salt thereof, a benzodiazepine, and tamsulosin.

29. 29. The method of claim 28, wherein the therapeutic agent is levothyroxine free acid or levothyroxine sodium.

30. 30. The method of claim 29, wherein the disease or disorder is hypothyroidism or a disease or disorder associated with or characterized by hypothyroidism.

31. 31. The method of claim 30, wherein the disease or disorder associated with or characterized by hypothyroidism is thyroiditis, Hashimoto's disease, myxedema, or myxedema coma / crisis.

32. 29. The method of claim 28, wherein the therapeutic agent is a benzodiazepine.

33. 33. The method of claim 32, wherein the benzodiazepine is diazepam.

34. 33. The method of claim 32, wherein the disease or disorder is anxiety, muscle spasms, or seizures.

35. 29. The method of claim 28, wherein the therapeutic agent is tamsulosin.

36. 36. The method of claim 35, wherein the disease or disorder is benign prostatic hyperplasia or kidney stones.

37. combining at least one ionization stabilizing excipient, an aprotic polar solvent system, and at least one therapeutic agent that is poorly soluble in an aqueous environment but readily soluble in the aprotic polar solvent system, thereby forming a storage-stable sustained-release therapeutic formulation that, when administered to a human or veterinary animal, results in the presence of therapeutic levels of the at least one therapeutic agent in the blood of the human or veterinary animal for an extended period of time compared to an immediate-release formulation comprising the at least one therapeutic agent.

1. A method for producing a storage-stable sustained-release therapeutic formulation of at least one therapeutic agent, comprising:

38. 38. The method of claim 37, wherein the therapeutic agent is selected from the group consisting of levothyroxine or a salt thereof, a benzodiazepine, and tamsulosin.

39. 39. The method of claim 38, wherein the therapeutic agent is levothyroxine free acid or levothyroxine sodium.

40. 39. The method of claim 38, wherein the benzodiazepine is diazepam.

41. 38. The method of claim 37, wherein the aprotic polar solvent system comprises or is dimethyl sulfoxide (DMSO).

42. 38. The method of claim 37, wherein the ionizable stabilizing excipient is an inorganic acid.

43. 43. The method of claim 42, wherein the inorganic acid is selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid.

44. 44. The method of claim 43, wherein the inorganic acid is sulfuric acid.

45. 43. The method of claim 42, wherein the inorganic acid is present in the formulation at a molar concentration ratio of between 2:1 and 3:1 relative to the concentration of the therapeutic agent in the formulation.

46. 46. ​​The method of claim 45, wherein the inorganic acid is present in the formulation at a molar concentration ratio of about 2.5:1 relative to the concentration of the therapeutic agent in the formulation.

47. 40. The method of claim 39, wherein the formulation comprises levothyroxine sodium in a concentration from about 5 mg / mL and sulfuric acid in a concentration from about 13 mM to about 15 mM.

48. 40. The method of claim 39, wherein the formulation comprises levothyroxine sodium in a concentration from about 10 mg / mL and sulfuric acid in a concentration from about 26 mM to about 28 mM.

49. 38. The method of claim 37, further comprising one or more additional pharmaceutically acceptable excipients.

50. 50. The method of claim 49, wherein the one or more additional pharmaceutically acceptable excipients are selected from the group consisting of sugars, sugar alcohols, preservatives, and polymers.

51. 51. The method of claim 50, wherein the sugar is trehalose or a salt or hydrate thereof.

52. 52. The method of claim 51, wherein the sugar is trehalose dihydrate.

53. 51. The method of claim 50, wherein the sugar alcohol is mannitol.

54. 51. The method of claim 50, wherein the preservative is benzyl alcohol.

55. 51. The method of claim 50, wherein the polymer is poly(lactic-co-glycolic acid) (PLGA).

56. 56. The method of claim 55, wherein the PLGA is an ester-terminated PLGA or an acid-terminated PLGA.

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