Uridine triacetate amorphous preparation and application thereof

Abstract

Disclosed is a dispersion of amorphous uridine triacetate in hydroxypropyl methylcellulose acetate succinate-MG and, optionally, copovidone. The amorphous dispersion composition allows for high loading of uridine. They also have good stability and oral bioavailability. They may be used to deliver exogenous uridine to a mammalian subject in need thereof, such as a subject having an energy failure disorder or certain other condition.

Description

Background Art

[0001] The pyrimidine nucleoside uridine has several potential clinical applications, including the treatment of fluoropyrimidine toxicity and mitochondrial energy failure disorders. The obstacle faced by uridine itself for treatment is poor oral bioavailability, which is measured in humans and mice at about 7% to 10%. Uridine triacetate, as an ester prodrug of uridine, can increase oral bioavailability to about 50% in its crystalline form. However, since relatively large doses of uridine triacetate are required for the treatment of certain disorders, up to 5 to 10 grams per dose, further improving bioavailability is important for reducing the required amount of drug (and corresponding costs) and especially for therapeutic indications that benefit from high peak concentrations (Cmax) of plasma uridine, such as mitochondrial diseases and other energy failure disorders, including but not limited to Huntington's Disease, Down Syndrome Dementia, age-related dementia and neuromuscular degeneration (sarcopenia) and acute brain injury (such as traumatic brain injury, concussion, ischemic or hemorrhagic stroke and asphyxia) are susceptible to secondary injury.

[0002] An important factor regulating the rate and extent of plasma uridine delivery following oral administration of uridine triacetate is the rate of dissolution of crystals of this compound. Uridine triacetate has a limited solubility in water, approximately 10 mg per ml.

[0003] Since relatively large doses of uridine triacetate are required, a high ratio of uridine triacetate to formulation excipients is important; however, a high ratio of uridine triacetate to excipients may result in poor stability, including crystal formation over time, which may cause functional and regulatory issues. In addition, the amount of excipients must be safe and compatible with the amount of uridine triacetate required. Summary of the invention

[0004] The present invention provides a composition comprising uridine triacetate formulated as an amorphous (non-crystalline) dispersion in one or more excipients, wherein the amount of amorphous uridine triacetate is about fifty weight percent to about sixty weight percent of the composition; one of the one or more excipients is hypromellose acetate succinate-MG; and the amount of hypromellose acetate succinate-MG is about thirty-seven weight percent to about forty weight percent of the composition.

[0005] The present invention provides a method of delivering exogenous uridine to a mammalian subject in need thereof, the method comprising administering to the subject an effective amount of a composition. The method of the present invention can be used to treat a mammalian subject who: suffers from a uridine deficiency or energy failure disorder; or is receiving fluoropyrimidine chemotherapy, and the exogenous uridine modulates the toxicity or efficacy, or both the toxicity and efficacy of the fluoropyrimidine chemotherapy. DETAILED DESCRIPTION

[0006] In an embodiment of the composition according to the present invention, one of the one or more excipients is copovidone. When the composition comprises copovidone, the amount of copovidone is preferably about twelve weight percent of the composition, such as about 12.5 weight percent.

[0007] In a preferred embodiment of the composition according to the present invention, the amount of amorphous uridine triacetate accounts for about sixty weight percent of the composition, and the amount of hypromellose acetate succinate-MG accounts for about forty weight percent of the composition. In another preferred embodiment, the amount of amorphous uridine triacetate accounts for about fifty weight percent of the composition, and the one or more excipients include an amount of hypromellose acetate succinate-MG accounting for about 37.5 weight percent of the composition and an amount of copolyvidone accounting for about 12.5 weight percent of the composition.

[0008] Compared to equimolar doses of crystalline uridine triacetate particles, the amorphous dispersion composition according to the invention allows for high loading of uridine triacetate, has adequate stability during storage, and has higher oral bioavailability. In addition, the taste and texture of the composition according to the invention are improved compared to currently commercialized crystalline uridine triacetate coated particles. The composition according to the invention can be optionally mixed with soft food (such as applesauce, pudding or yogurt) up to about thirty minutes before ingestion.

[0009] Typically, an amorphous formulation is used when the active pharmaceutical ingredient (API) is extremely poorly soluble, thereby making small amounts of the API more soluble and more bioavailable. It is not typically used with moderately soluble APIs such as uridine triacetate. Amorphous formulations of uridine triacetate allow for practical oral delivery of large amounts of API. In the expressions "amorphous formulation" and "amorphous dispersion" of uridine triacetate, the term "amorphous" refers to the fact that uridine triacetate is non-crystalline.

[0010] Amorphous dispersions are produced by one of two basic methods: spray drying or hot melt extrusion. In spray drying, the drug and excipients (usually including polymers) are dissolved in a volatile solvent. The solution is sprayed out in the form of a fine mist, and the solvent is evaporated by heating or vacuum, leaving small particles collected. In hot melt extrusion, the drug and excipient are melted, mixed, extruded and cooled together to obtain a solid material that can be ground to form particles of appropriate size. According to the present invention, the particles can be ground into any conventional size. For example, the D50 of the particles is preferably about 200 microns.

[0011] The amorphous dispersion particles are optionally further formulated into aggregates, coated with taste masking agents or modified release excipients. The particles can also be incorporated into suspensions, capsules or tablets, including microtablets small enough to be administered through a gastrostomy tube or nasogastric tube or by an oral administration syringe.

[0012] Uridine triacetate readily crystallizes under aqueous conditions. Therefore, unexpectedly, hot melt extrusion compositions such as Formulation 1 (60% API / 40% HPMCAS-MG) and Formulation 2 (50% API / 37.5% HPMCAS-MG / 12.5% ​​copovidone) were successfully prepared, showing stability and overcoming the challenge of APIs with very high drug loads (≧50% uridine triacetate) easily recovering a crystalline form, especially in the presence of moisture.

[0013] In the field of hot melt extrusion, surfactants or plasticizers are usually added. However, it was found that hot melt extrusion of the formulation according to the present invention does not require the addition of surfactants or plasticizers (Examples 1 and 2). Without wishing to be bound by theory, it seems that uridine triacetate itself can act as a plasticizer.

[0014] The compositions of the present disclosure are beneficial for conditions or diseases that benefit from the delivery of exogenous uridine, which can include uridine deficiency (e.g., hereditary orotic aciduria or biallelic CAD deficiency), toxicity and / or efficacy modulation of fluoropyrimidine chemotherapy, and various energy failure conditions, particularly conditions or diseases involving inherited or acquired mitochondrial dysfunction. The compositions of the present disclosure are specifically intended to optimize the treatment of energy failure conditions, which include:

[0015] 1. Primary mitochondrial diseases (PMDs), in which pathogenic mutations occur in either mitochondrial DNA or nuclear DNA, resulting in impaired mitochondrial energy production.

[0016] 2. Chronic neurodegenerative diseases characterized by pathogenic defects in mitochondrial function, including but not limited to Huntington's disease, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and Down syndrome dementia.

[0017] 3. Neuromuscular dysfunction or wasting characterized by pathogenic mitochondrial dysfunction, including sarcopenia (age-related or premature due to exacerbation of chronic kidney disease, COPD, or heart failure), cachexia, muscle disuse atrophy, and circulatory insufficiency (such as peripheral arterial disease or intermittent claudication).

[0018] 4. Acute brain injury, including but not limited to traumatic brain injury, stroke (ischemic and hemorrhagic), birth asphyxia, cardiac arrest, drowning and carbon monoxide poisoning.

[0019] 5. Acute or chronic myocardial ischemia, left ventricular heart failure, right ventricular heart failure (eg, caused by pulmonary hypertension).

[0020] A common feature of these energy failure disorders, in the context of successful treatment using the compositions of the present disclosure, is the presence of inherited or acquired mitochondrial dysfunction resulting in an impaired ability of the mitochondria to reserve (or spare) energy, i.e., the ability to rapidly increase cellular energy production in response to demand, a critical property since ATP cannot be stored but must be continuously produced by mitochondrial oxidative phosphorylation and glycolysis. The gap between energy production and utilization is a major determinant of cellular dysfunction and death in a variety of diseases and conditions exemplified by those listed above.

[0021] For the treatment of energy failure disorders, the main pharmacokinetic and pharmacodynamic goals are to deliver enough uridine into cells to increase the uridine nucleotides in the cell (and specifically in the mitochondria), especially in the mitochondrial intermembrane space (IMS). Without being bound by a specific mechanism of action, one contribution of exogenous uridine to improve mitochondrial bioenergetic capacity is to activate the mitochondrial ATP-sensitive potassium channel in the inner mitochondrial membrane by increasing the concentration of uridine diphosphate (UDP) in the mitochondrial intermembrane space (IMS). UTP (uridine triphosphate) and UDP are balanced by the ratio of ATP and ADP with nucleoside diphosphate kinase, which spans the inner and outer mitochondrial membranes in the IMS. The ATP / ADP ratio and therefore the UTP / UDP ratio can serve as an indicator of the bioenergetic state of the cell, and when mitochondrial ATP synthesis is impaired or cytoplasmic energy utilization is increased to a replenishment rate exceeding oxidative phosphorylation or glycolysis, the ADP and UDP in the IMS will increase. In the compositions of the present disclosure, exogenous uridine delivered by uridine triacetate increases the total amount of IMS uridine nucleotides, enabling a more rapid and extensive increase in UDP in the IMS when the bioenergetic capacity of the cell is reduced. Activation of mitochondrial ATP-sensitive potassium channels by UDP prevents the destruction of optimal mitochondrial structure during impending energy failure, in particular, mitigating the osmotic expansion of the width of the IMS and the concomitant contraction of the mitochondrial matrix (the inner compartment of the mitochondria). The width of the IMS is a determining factor in the efficiency of fuel oxidation rate and the transfer of bioavailable energy from ATP within the mitochondria to phosphocreatine in the cytosol; the latter enables the phosphorylation (energy) potential of the entire cell to reach equilibrium more quickly. The efficient function of mitochondrial creatine kinase (CK) relies on maintaining the width of the IMS at approximately 90 angstroms, allowing the enzyme to physically bridge the inner and outer mitochondrial membranes, which can retain ATP+ADP within the mitochondria while exporting phosphocreatine (CrP) produced by creatine to cytoplasmic sites (where ATP can be locally regenerated from CrP). By promoting the maintenance of IMS width, the compositions of the present disclosure can alleviate the decline in the ability to store energy in energy failure conditions, thereby reducing cellular dysfunction and improving health and survival. The energy state dependence of UDP production in the IMS enables chronic treatment of energy failure conditions without the adverse consequences of other classes of drugs that can open ATP-sensitive channels, but even when cells are full of energy, this can lead to inappropriate swelling of the mitochondrial matrix and a reduction in the width of the IMS to less than the optimal distance, which can impair oxidative phosphorylation. Therefore, compared with other modulators of mitochondrial ATP-sensitive potassium channel activity, the compositions of the present disclosure have unique advantages, especially in the chronic treatment of energy failure conditions.

[0022] The optimal single dose of the composition disclosed herein for treating energy failure disorders in human patients comprises 30 mg / kg to 120 mg / kg of uridine triacetate (plus polymers and other excipients), more specifically 60 mg / kg to 100 mg / kg of uridine triacetate (e.g., as an active agent in a composition of 100 mg / kg to 167 mg / kg with 60% uridine triacetate in Example 1 below, or as an active agent in a composition of 120 mg / kg to 200 mg / kg with 50% uridine triacetate loading in Example 2 below). 1 to 4 doses are administered orally per day, generally twice per day, approximately 8 to 12 hours apart.

[0023] For treatment of disorders involving the central nervous system, the pharmacokinetic goal is to achieve saturation transport of uridine across the blood-brain barrier (primarily via endothelial pyrimidine transporters of the ENT family) to achieve peak plasma uridine concentrations in excess of 100 micromolar. Optimal treatment of peripheral organs can be achieved at lower plasma uridine concentrations than required for treatment of the brain because restrictive epithelial barriers comparable to the blood-brain barrier do not exist in most other tissues.

[0024] Abbreviations and definitions:

[0025] HPMCAS means hydroxypropyl methylcellulose acetate succinate (also known as hydroxypropyl methylcellulose succinate).

[0026] KF means Karl Fischer method for determining water content.

[0027] RH means relative humidity.

[0028] CAD is an enzyme complex that catalyzes the critical first step in pyrimidine nucleotide biosynthesis; carbamoyl phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase.

[0029] Uridine triacetate is also known as 2',3',5'-tri-O-acetyluridine or triacetyluridine.

[0030] The present invention will be better understood by reference to the following examples, which illustrate but do not limit the invention described herein.

[0031] Examples

[0032] Example 1: Amorphous solid dispersion composed of 60% uridine triacetate and 40% hypromellose acetate succinate-MG

[0033] An amorphous solid dispersion (ASD) consisting of 60% uridine triacetate (w / w) active pharmaceutical ingredient (API) and 40% hydroxypropyl methylcellulose acetate succinate-MG (HPMCAS-MG) polymer was prepared by mixing uridine triacetate with hydroxypropyl methylcellulose acetate succinate-MG in the ratios described in Table 1 and then hot melt extruding using a twin screw extruder. The cooled extrudate was ground to a D50 of approximately 200 microns.

[0034] Table 1: Materials used for 40% uridine triacetate and 60% polymer amorphous solid dispersions

[0035]

[0036] Example 2: Amorphous solid dispersion composed of 50% uridine triacetate, 37.5% hypromellose acetate succinate-MG, and 12.5% ​​copovidone

[0037] An amorphous solid dispersion (ASD) consisting of 50% uridine triacetate (w / w) active pharmaceutical ingredient (API), 37.5% hypromellose acetate succinate-MG (HPMCAS-MG) and 12.5% ​​copovidone was prepared by mixing uridine triacetate with HPMCA succinate-MG and copovidone polymer in the ratios described in Table 2 and then hot melt extruded using a twin screw extruder. The cooled extrudate was ground to a D50 of approximately 200 microns.

[0038] Table 2: Materials used for 60% uridine triacetate and 40% polymer amorphous solid dispersion

[0039]

[0040] Example 3: Stability of ASD Formulations 1 and 2 under long-term (25°C / 60% RH) and accelerated (40°C / 75% RH) conditions

[0041] Formulation 1 (60% API) was stable for 12 weeks under long-term (Table 3: 25°C / 60% RH) and accelerated conditions (Table 4: 40°C / 75% RH) with no increase in impurities or crystallinity as detected by HPLC and light microscopy.

[0042] Formulation 2 (50% API) was stable for 12 weeks under long-term (Table 5: 25°C / 60%RH) and accelerated conditions (Table 6: 40°C / 75%RH) with no increase in impurities or crystallinity as detected by HPLC and light microscopy.

[0043] Table 3: Formulation 1 (60% API): 25°C / 60%RH Stability

[0044]

[0045]

[0046] Table 4: Formulation 1 (60% API): 40°C / 75%RH Stability

[0047]

[0048] Table 5: Formulation 2 (50% API): 25°C / 60%RH Stability

[0049]

[0050]

[0051] Table 6: Formulation 2 (50% API): 40°C / 75%RH Stability

[0052]

[0053] Example 4. Treatment of primary mitochondrial diseases

[0054] A 10-year-old male patient was diagnosed with primary mitochondrial disease by identification of a pathogenic mutation known to impair mitochondrial oxidative phosphorylation (by whole-exome sequencing and comparison to a database of known pathogenic genetic variants) combined with symptoms consistent with PMD, which in this case included recurrent seizures, developmental delay, proximal renal tubular acidosis requiring bicarbonate supplementation, and exercise intolerance (premature fatigue during exercise).

[0055] In treatment with the disclosed compositions, the initial dose is 60 mg / kg body weight of uridine triacetate twice daily, administered before meals in the morning and evening. Within about a week, seizure frequency decreases by more than 50%, and the daily bicarbonate requirement required to compensate for excess urine excretion due to proximal renal tubular acidosis decreases from 200 milliequivalents per day to less than 25 milliequivalents. The therapeutic goal is to maintain plasma bicarbonate above 20 milliequivalents per liter. After a few more weeks, endurance during exercise improves, as measured by standard clinical measures of timed walking distance and subjective fatigue.

[0056] The dose of uridine triacetate was increased to 100 mg / kg / dose of uridine triacetate twice daily, and the seizure frequency was further reduced.

Claims

1. A composition comprising amorphous uridine triacetate dispersed in one or more excipients, wherein The amount of amorphous uridine triacetate is about fifty weight percent to about sixty weight percent of the composition; One of the one or more excipients is hypromellose acetate succinate-MG; and The amount of the hypromellose acetate succinate-MG is about thirty-seven weight percent to about forty weight percent of the composition.

2. The composition of claim 1, wherein one of the one or more excipients is copovidone.

3. The composition of claim 2, wherein the amount of copovidone accounts for about twelve weight percent of the composition.

4. The composition of claim 1, wherein the amount of amorphous uridine triacetate is about sixty weight percent of the composition, and the amount of hypromellose acetate succinate-MG is about forty weight percent of the composition.

5. The composition of claim 1, wherein the amount of amorphous uridine triacetate is about fifty weight percent of the composition, and the one or more excipients comprise hypromellose acetate succinate-MG in an amount of about 37.5 weight percent of the composition and copovidone in an amount of about 12.5 weight percent of the composition.

6. The composition according to any one of claims 1 to 5, produced by hot melt extrusion.

7. The composition of claim 6, wherein the composition comprises particles having a D50 of about 200 microns.

8. The composition according to any one of claims 1 to 5, wherein the composition does not contain a plasticizer other than the amorphous uridine triacetate.

9. A method of delivering exogenous uridine to a mammalian subject in need thereof, the method comprising administering to the mammalian subject an effective amount of the composition of any one of claims 1 to 5.

10. The method of claim 9, wherein the mammalian subject suffers from a uridine deficiency or an energy failure disorder; or is receiving fluoropyrimidine chemotherapy, and the exogenous uridine modulates the toxicity or efficacy, or both, of the fluoropyrimidine chemotherapy.

11. A method for treating a mammalian subject suffering from an energy failure disorder, the method comprising administering to the mammalian subject an amount of the composition of any one of claims 1 to 5 effective to treat the mammalian subject.

12. The method of claim 11, wherein the energy failure disorder is selected from the group consisting of: primary mitochondrial disease; chronic neurodegenerative disease characterized by pathogenic defects in mitochondrial function; neuromuscular dysfunction or wasting characterized by pathogenic mitochondrial dysfunction; acute brain injury; a cardiac condition selected from the group consisting of myocardial ischemia and ventricular heart failure.

13. The method of claim 12, wherein the chronic neurodegenerative disease characterized by pathogenic defects in mitochondrial function is selected from the group consisting of Huntington's Disease, Alzheimer's Dementia, Parkinson's Disease, Amyotrophic Lateral Sclerosis, and Down Syndrome Dementia.

14. The method of claim 12, wherein the neuromuscular dysfunction or wasting characterized by pathogenic mitochondrial dysfunction is selected from the group consisting of sarcopenia, cachexia, muscle disuse atrophy, and circulatory insufficiency.

15. The method of claim 12, wherein the acute brain injury is selected from the group consisting of traumatic brain injury, stroke, acute brain injury caused by birth asphyxia, acute brain injury caused by cardiac arrest, acute brain injury caused by drowning, and acute brain injury caused by carbon monoxide poisoning.

16. The method of claim 11, wherein the mammalian subject is a human subject and the composition is administered in one or more doses, each dose comprising 30 mg to 120 mg of uridine triacetate per kg body weight of the human subject.

17. The method of claim 16, wherein the dose comprises 60 mg to 100 mg of uridine triacetate per kg of body weight of the human subject.

18. The method of claim 16 or 17, wherein the composition is administered orally.

19. The method of any one of claims 16 to 18, wherein one to four doses of the composition are administered to the subject per day.

20. The method of claim 19, wherein two doses of the composition are administered to the subject daily, wherein the second dose and each subsequent dose during the course of treatment is administered 8 to 12 hours after the previous administration.

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