U.S. patent application number 16/870984 was filed with the patent office on 2020-08-27 for hydrophobic highly branched carbohydrate polymers.
This patent application is currently assigned to Purdue Research Foundation. The applicant listed for this patent is Purdue Research Foundation. Invention is credited to Yuan Yao, Jingmin Zhang.
Application Number | 20200268894 16/870984 |
Document ID | / |
Family ID | 1000004813127 |
Filed Date | 2020-08-27 |
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United States Patent
Application |
20200268894 |
Kind Code |
A1 |
Yao; Yuan ; et al. |
August 27, 2020 |
HYDROPHOBIC HIGHLY BRANCHED CARBOHYDRATE POLYMERS
Abstract
A material comprising a highly branched carbohydrate polymer, a
polyalkylene glycol (or polyalkylene oxide) linked to the highly
branched carbohydrate polymer, and a hydrophobic or amphiphilic
group linked to the highly branched carbohydrate polymer and/or the
polyalkylene glycol (or polyalkylene oxide), is described. Methods
of making and using the material, as well as a soluble composition
that contains the material and a hydrophobic solute compound, are
also described.
Inventors: |
Yao; Yuan; (West Lafayette,
IN) ; Zhang; Jingmin; (West Lafayette, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Purdue Research Foundation |
West Lafayette |
IN |
US |
|
|
Assignee: |
Purdue Research Foundation
West Lafayette
IN
|
Family ID: |
1000004813127 |
Appl. No.: |
16/870984 |
Filed: |
May 10, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15764624 |
Mar 29, 2018 |
10653784 |
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PCT/US2016/055180 |
Oct 3, 2016 |
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16870984 |
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62236372 |
Oct 2, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 31/496 20130101;
C08J 2305/00 20130101; A61K 31/635 20130101; A61K 31/343 20130101;
A61K 9/1676 20130101; A61K 47/40 20130101; C08J 3/24 20130101; A61K
9/1682 20130101; C08B 37/0009 20130101; A61K 31/12 20130101; A61K
9/10 20130101; A61K 31/167 20130101; A61K 47/38 20130101; A61K
9/5161 20130101; A61K 31/337 20130101; A61K 47/36 20130101 |
International
Class: |
A61K 47/36 20060101
A61K047/36; C08B 37/00 20060101 C08B037/00; A61K 9/10 20060101
A61K009/10; A61K 47/40 20060101 A61K047/40; A61K 9/16 20060101
A61K009/16; A61K 9/51 20060101 A61K009/51; A61K 47/38 20060101
A61K047/38; A61K 31/12 20060101 A61K031/12; A61K 31/167 20060101
A61K031/167; A61K 31/337 20060101 A61K031/337; A61K 31/343 20060101
A61K031/343; A61K 31/496 20060101 A61K031/496; A61K 31/635 20060101
A61K031/635; C08J 3/24 20060101 C08J003/24 |
Goverment Interests
GOVERNMENT FUNDING
[0002] The present invention was made with Government support under
Grant Nos. 1346431 and 1310475 awarded by the National Science
Foundation. The Government has certain rights in the invention.
Claims
1. A material comprising: a highly branched carbohydrate polymer; a
polyalkylene glycol, linked to the highly branched carbohydrate
polymer; and a hydrophobic or amphiphilic group linked to the
highly branched carbohydrate polymer and/or the polyalkylene
glycol.
2. The material of claim 1, wherein the material is a solubilizing
agent.
3. The material of claim 1, wherein the hydrophobic or amphiphilic
group is linked to polyalkylene glycol.
4. The material of claim 1, wherein the highly branched
carbohydrate polymer has a dendritic or dendrimer-like
structure.
5. The material of claim 1, wherein the highly branched
carbohydrate polymer is a highly branched alpha-D-glucan.
6. The material of claim 1, wherein the highly branched
carbohydrate polymer is glycogen, phytoglycogen, or a modified form
thereof.
7. The material of claim 1, wherein the polyalkylene glycol is
polyethylene glycol or polypropylene glycol.
8. The material of claim 1, wherein the hydrophobic or amphiphilic
group is selected from the group consisting of acetate group,
propionate group, butyrate group, octenyl succinate group, and
combinations thereof.
9. The material of claim 1 is octenylsuccinate hydroxypropyl
phytoglycogen (OHPP).
10. A composition comprising: niclosamide; and the material of
claim 1.
11. A pharmaceutical formulation comprising the composition of
claim 10, and with or without other pharmaceutically acceptable
component.
12. The pharmaceutical formulation of claim 11 in which the
formulation is in dosage form.
13. A method of making a composition of claim 10 comprising:
combining niclosamide with the material of claim 1, with or without
other pharmaceutically acceptable material.
14. The method of claim 13 in which the niclosamide is combined
with the material of claim 1, with or without other
pharmaceutically acceptable material, using a method selected from
the group consisting of extrusion, mixing, spray drying, vacuum
drying, kneading, rolling, ultra-sonication, vibration, milling,
and combinations thereof.
15. A composition comprising: niclosamide; and octenylsuccinate
hydroxypropyl phytoglycogen (OHPP).
16. A pharmaceutical formulation comprising the composition of
claim 15, and with or without other a pharmaceutically acceptable
component.
17. The pharmaceutical formulation of claim 16 in which the
formulation is in dosage form.
18. A method of making a composition of claim 15 comprising:
combining niclosamide with OHPP, with or without other
pharmaceutically acceptable material.
19. The method of claim 18 in which the niclosamide is combined
with OHPP, with or without another pharmaceutically acceptable
material, using a method selected from the group consisting of
extrusion, mixing, spray drying, vacuum drying, kneading, rolling,
ultra-sonication, vibration, milling, and combinations thereof.
20. A method for administering niclosamide to a subject comprising:
administering to the subject a pharmaceutical formulation or dosage
form of claim 11 using pharmaceutical acceptable routes.
21. A method for administering niclosamide to a subject comprising:
administering to the subject a pharmaceutical formulation or dosage
form of claim 16 using pharmaceutical acceptable routes.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application Ser. No. 62/236,372, filed on Oct. 2, 2015, the
disclosure of which is hereby incorporated by reference in its
entirety.
TECHNICAL FIELD
[0003] The present disclosure relates generally to compositions for
increasing the solubility and stability of solute compounds
therein, and more particularly to compositions including highly
branched carbohydrate polymers or polysaccharides (hereafter,
highly branched carbohydrate polymers or polysaccharides indicate
their original forms or modified forms), solubilizing agents that
may be used to improve solubility, stability, and/or
bioavailability of solute compounds for the food, nutraceutical,
personal care, skin care, cosmetics, pharmaceuticals, medical,
paint and coating, and agricultural industries.
BACKGROUND
[0004] In industries such as food, feed, agriculture, drug, animal
drug, personal care, skin care, etc., the use of certain
ingredients or extracts is difficult since their constituent
materials have low or poor solubility in water, which leads to low
stability, accessibility, availability, or bioavailability.
Examples of such ingredients, synthetic compounds, or extracts can
include phenolic compounds (e.g., flavonoids, curcuminoids),
carotenoids, and active pharmaceutical ingredients (APIs, e.g.,
drugs), as well as raw or purified extracts from herbs, microbes
and animals.
[0005] For drugs administered via oral route, drugs must be
dissolved for the molecules to permeate through cell membranes to
reach the systemic circulation. The solubility and permeability of
drug are largely affected by their physicochemical properties. In
addition to neutral drugs (e.g. griseofulvin), a large number of
drug compounds are either weak acids (e.g. ibuprofen) or bases
(e.g. itraconazole). For these drugs, their un-ionized and ionized
forms in water affect their solubility and permeability. Along the
GI tract, the small intestine provides the largest surface area for
drug absorption, and its membranes are more permeable than those in
the stomach. In general, the intestinal pH (5-7) affects the
solubility of drugs and their membrane permeability. For weak
acids, their solubility is improved due to ionization; for weak
bases, their solubility is reduced due to un-ionization.
[0006] It is estimated that roughly 40% of new drug molecules
present drug delivery challenges due to their low solubility. The
Biopharmaceutics Classification System (BCS) was developed as a
systematic approach to classify Active Pharmaceutical Ingredients
(APIs) based on their solubility and permeability. Based on the
BCS, drug solubilization is necessary for the delivery of compounds
in Class II (low solubility, high permeability) and Class IV (low
solubility, low permeability). In particular, compounds in Class
II, such as griseofulvin, make the group for which the
solubilization technologies can readily solve the drug delivery
problem.
[0007] Accordingly, there are different approaches for addressing
the solubility issue of active ingredients (AIs), such as
nanoemulsions, dendrimers, block copolymer micelles, cocrystal
formation, and amorphous dispersions. The amorphous dispersion
approach has drawn great interest in drug formulation due to
several reasons. First, it has the potential to eliminate the
solubility limitations imposed by the thermodynamic stability of
crystal lattice. Second, by the action of polymer matrix it is
possible to induce supersaturation over time scales comparable to
those required for systemic absorption.
[0008] One particular example of such ingredients or extracts
includes phenolic compounds, such as quercetin and curcumin.
Quercetin and curcumin are strong antioxidants and have
anti-inflammatory, antiviral, and anti-cancer effects. In
particular, curcumin is a potent anti-cancer drug that can be used
clinically. However, their low solubility prohibits their use in
food, nutraceutical, cosmetic, and medical formulations. To address
this problem, a variety of techniques have been employed to improve
the water-solubility of such low or non-soluble phenolic compounds.
For example, it has been proposed to improve the solubility or
bioavailability of curcumin using specific compounds (e.g.,
piperine), polymeric nanoparticle encapsulation, or surfactant
micelles. However, these methods are expensive and/or have limited
capability to solubilize phenolic compounds. In addition, some of
these strategies are simply ineffective.
[0009] Poor water solubility of some active pharmaceutical
ingredients (APIs), such as a number of drugs is one of the major
problems in drug formulation and drug absorption. Systems to
improve the water solubility of these drugs are essential for their
bioavailability. For example, application of paclitaxel in cancer
therapy has been limited by its low water solubility, and current
practice of dissolving paclitaxel usually leads to short-term
physical stability with quick precipitation of drug molecules. To
enhance paclitaxel solubility and physical stability, solvents have
been used to disperse drug molecules. To be effective, however, the
concentration of solvents needs to be very high, which may lead to
difficulties in formulation and administration.
[0010] Another example is ibuprofen. Ibuprofen is a nonsteroidal
anti-inflammatory drug (NSAID), and a core medicine in the WHO
Model List of Essential Medicines. It is broadly used to relieve
symptoms of arthritis and fever and as an analgesic where there is
an inflammatory component and dysmenorrhea. Ibuprofen belongs to
Biopharmaceutics Classification System (BCS) class II, for which
the rate of drug dissolution or drug solubility is the
rate-limiting step in the absorption.
[0011] Another example is griseofulvin. Griseofulvin is a widely
used antifungal drug in the treatment of mycotic diseases of skin,
hair and nails. Griseofulvin is poorly soluble in water and has
been used as a standard in the research to increase drug
bioavailability.
[0012] Another example is itraconazole. Itraconazole is an orally
active triazole antimycotic agent and has been used to treat
various fungal infections including histoplasmosis, blastomycosis
and oncomycosis. It is a weakly base drug with poor water
solubility.
[0013] Other examples are aripiprazole, celecoxib, imatinib,
ezetimibe, modafinil, dutasteride, ciclosporin, darunavir,
raloxifene, olmesartan, and cinacalcet. Their low solubility
affects their efficacy at various levels.
[0014] Similar issues persist in industries related to the
extraction and formulation of medicinal, nutritional, or functional
materials from plant, microbial, or animal organisms, such as
herbal extracts, Chinese medicine, and colorants. In such
industries, there are a number of extraction processes, including:
(1) aqueous extraction; (2) solvent-based extraction, and (3)
supercritical fluid extraction. In many circumstances, the solute
compound (or materials) has low water solubility, which makes it
difficult to formulate as a product. Additionally, in industries
related to feed, animal drugs, personal care, cosmetics, paints,
pesticides, herbicides, or other food and non-food areas, the low
solubility of certain materials in products is the source of
numerous difficulties in formulation, processing and/or the
function of such products.
SUMMARY
[0015] Compositions for increasing the solubility and stability of
solute compounds are described herein. More particularly, the
inventors have surprisingly discovered that highly branched
carbohydrate polymers, such as alpha-D-glucans, when subjected to
two steps of substitution, for which the first step was reaction
with a polyalkylene glycol or polyalkylene oxide-forming agents
(e.g., alkylene oxides) and the second step was with hydrophobic or
amphiphilic groups, may have high capability to increase the
solubility of poorly water-soluble compounds, including active
pharmaceutical ingredients, hydrophobic nutrients, as well as other
types of compounds with low water solubility. Thus these modified
highly branched carbohydrate polymers can be used as solubilizing
agents. In the present invention, a solubilizing agent is a
compound, molecule, material, substance, mixture, or composition
that is able to improve the solubility, dissolution rate, and/or
stability in solution of a hydrophobic solute compound.
[0016] The highly branched carbohydrate polymer can be highly
branched alpha-D-glucans such as glycogen, phytoglycogen,
amylopectin, dextran, maltodextrins, dextrins, and other branched
glucans naturally occurring, modified natural glucans, or
artificially synthesized branched materials such as those made from
glucan chains using starch branching enzyme, glucan branching
enzyme, or their functional analogs.
[0017] The highly branched carbohydrate polymer can also be
non-glucan, but highly branched materials, such as gum Arabic and
its derivatives, and arabinoxylan and its derivatives. In other
embodiments, the highly branched carbohydrate polymer is a
synthesized branched material such as polydextrose and its
derivatives.
[0018] The highly branched carbohydrate polymer can also be a
material that is a "hybrid," for example, the material formed
through covalent connections between two types of polysaccharide,
between a polysaccharide and a protein (or a lipid), or between a
polysaccharides and a monosaccharide or a oligosaccharide.
BRIEF DESCRIPTION OF THE FIGURES
[0019] The present invention may be more readily understood by
reference to the following drawings, wherein:
[0020] FIG. 1 provides a hypothesized (non-binding) cut-away
diagram of an octenylsuccinate hydroxypropyl phytoglycogen (OHPP)
nanoparticle that hosts multiple API molecules. The hydroxypropyl
(HP) groups perform as "bridging units" that provide the
flexibility of OS groups to interact with API molecules. The
octenylsuccinate hydroxypropyl (OHP) layer (or layers) may
stabilize dispersed API.
[0021] FIG. 2 provides a graph showing the solubility of
niclosamide when incorporated with OHPP, HPMCAS, and Soluplus
(Soluplus.RTM., BASF), as compared with that of niclosamide alone.
The ratio between niclosamide and excipient was 1/3, with total
dispersed API of 2,500 .mu.g/mL in HBSS buffer (37.degree. C.). The
mixing time was 2 h before subjecting the dispersion to
centrifugation to collect supernatant for API quantification.
[0022] FIG. 3 provides a graph showing the solubility of paclitaxel
when incorporated with OHPP, HPMCAS, and Soluplus, as compared with
that of paclitaxel alone. The ratio between paclitaxel and
excipient was 1/3, with total dispersed paclitaxel of 2,500
.mu.g/mL in HBSS buffer (37.degree. C.). The mixing time was 2 h
before subjecting the dispersion to centrifugation to collect
supernatant for paclitaxel quantification.
[0023] FIG. 4 provides a graph showing the solubility of
griseofulvin when incorporated with OHPP, HPMCAS, and Soluplus, as
compared with that of griseofulvin alone. The ratio between
griseofulvin and excipient was 1/3, with total dispersed
griseofulvin of 2,500 .mu.g/mL in HBSS buffer (37.degree. C.). The
mixing time was 2 h before subjecting the dispersion to
centrifugation to collect supernatant for griscofulvin
quantification.
[0024] FIG. 5 provides a graph showing the solubility of docetaxel
when incorporated with OHPP, HPMCAS, and Soluplus, as compared with
that of docetaxel alone. The ratio between docetaxel and excipient
was 1/3, with total dispersed docetaxel of 2,500 .mu.g/mL in HBSS
buffer (20.degree. C.). The mixing time was 10 min before
subjecting the dispersion to centrifugation to collect supernatant
for docetaxel quantification.
[0025] FIG. 6 provides a graph showing the solubility of
itraconazole when incorporated with OHPP, HPMCAS, and Soluplus, as
compared with that of itraconazole alone. The ratio between
itraconazole and excipient was 1/3, with total dispersed
itraconazole of 2,500 .mu.g/mL in HBSS buffer (20.degree. C.). The
mixing time was 10 min before subjecting the dispersion to
centrifugation to collect supernatant for itraconazole
quantification.
[0026] FIG. 7 provides a graph showing the solubility of curcumin
when incorporated with OHPP, HPMCAS, and Soluplus, as compared with
that of curcumin alone. The ratio between curcumin and excipient
was 1/9, with total dispersed curcumin of 1,000 .mu.g/mL in HBSS
buffer (37.degree. C.). The mixing time was 2 h before subjecting
the dispersion to centrifugation to collect supernatant for
curcumin quantification.
[0027] FIG. 8 provides a graph showing the solubility of celecoxib
when incorporated with OHPP, HPMCAS, and Soluplus, as compared with
that of celecoxib alone. The ratios between celecoxib and each
excipient was 1/5, with total dispersed API of 1,000 .mu.g/mL in
HBSS buffer (37.degree. C.). The mixing time was 2 h before
subjecting the dispersion to centrifugation to collect supernatant
for celecoxib quantification. The weight ratio of celecoxib, OHPP,
and HPMCAS was 1, 3, and 2 respectively for the Cel-OHPP-HPMCAS
preparation.
[0028] FIG. 9 provides an image of the .sup.1H NMR spectra of
hydrolyzed octenylsuccinate hydroxypropyl phytoglycogen (OHPP).
[0029] FIG. 10 provides a graph showing the concentration of APIs
in the basolateral compartment of Caco-2 cell monolayer as affected
by the use of OHPP. Nic-1000 and Nic-100: supernatant from
centrifuged dispersion of pure niclosamide in HBSS at dispersing
dose of 1000 and 100 .mu.g/mL, respectively. Cel-1000 and Cel-100:
supernatant from centrifuged dispersion of pure celecoxib in HBSS
at dispersing dose of 1000 and 100 .mu.g/mL, respectively.
Nic-OHPP-100: supernatant from centrifuged dispersion of Nic-OHPP
in HBSS at dispersing dose of 100 .mu.g/mL (for pure niclosamide).
Cel-OHPP-HPMCAS-100: supernatant of Cel-OHPP-HPMCAS dispersed in
HBSS buffer at 100 .mu.g/mL.
[0030] FIGS. 11A and 11B provide graphs showing the MTT cell
viabilities of (A) HeLa cells after a 48 h-exposure to paclitaxel
and (B) PC-3 cells after a 48 h-exposure to niclosamide, as
affected by the apparent doses of APIs delivered using various
types of excipient (DMSO, OHPP, HPMCAS, and Soluplus). For Pac-DMSO
and Nic-DMSO, the testing preparation was made through dissolving
the API with DMSO and then diluting the solution to 0.003 to 500
g/mL. For API-excipient preparations, each individual API-excipient
complex (in solid form) was first mixed in cell culture medium to
achieve a total API amount of 2.5 mg/mL, and then the mixture was
centrifuged at 16,000 g for 5 min. The supernatant thus collected,
which was deemed as having an apparent API dose of 2.5 mg/mL, was
diluted 5 to 819,200 times to achieve a group of apparent API doses
ranging from 0.003 to 500 .mu.g/mL.
DETAILED DESCRIPTION
[0031] An aqueous solution, as used herein, is any solution in
which water is the main solvent. The aqueous solution can include
other solvents, and one or more additional solutes, while still
remaining an aqueous solution. Examples of aqueous solutions
include buffered solutions, salt water, drinks such as coffee, tea,
beer, wine, and fruit juice, vinegar, etc. An aqueous solution can
also be a phase of an emulsion (e.g. cream, lotion), a colloid, a
suspension, or aerosol.
[0032] Solubility, as used herein, refers to the ability of a
solute compound to dissolve or disperse in a liquid solvent to form
a homogeneous solution or dispersion of the solute in the
solvent.
[0033] Practically, the term "solubility" indicates the amount of
solute in a given solvent that remains stable in a dispersed state
over a defined or desirable period of time, against various forms
of precipitation, sedimentation, aggregation, flocculation,
gelation, coacervation, creaming, agglomeration, coalescence, or
phase separation. Technically, the solubility defined here can be
measured using a centrifugation, a filtration, or an
ultrafiltration approach. For example, for a centrifugation
approach, the mixture of solute and liquid solvent is subjected to
centrifugation and the amount of solute in the supernatant is
determined to calculate the solubility. For an ultrafiltration
approach, the mixture of solute and liquid solvent is subjected to
ultrafiltration and the amount of solute in the permeated fluid is
determined to calculate the solubility.
[0034] The solubility of a solute compound can vary depending on a
number of factors, such as the temperature, pressure, ionic
strength, types of buffer, presence of other solute(s) in the
solvent, and the pH value of the solution. Increased solubility, as
used herein, refers to the ability for an increased amount of a
solute to dissolve or disperse in an aqueous solution of a given
composition at a given set of conditions and remain stable. The
extent of the solubility of a substance in a specific solvent is
measured as the kinetically stable concentration under a defined
set of measuring conditions. Therefore, adding more solute may or
may not increase the concentration of the solute in the solution or
dispersion. Solubility is commonly expressed as a
concentration.
Solubilizing Agent
[0035] A solubilizing agent is a compound, molecule, material,
substance, mixture, or composition that is able to improve the
solubility, dissolution rate, and/or stability in solution of a
hydrophobic solute compound. In particular, the solubility of a
solute compound in presence of a solubilizing agent is higher than
the solubility of the solute compound in absence of a solubilizing
agent.
[0036] As used herein, the terms "alkyl", "alkenyl", and the prefix
"alk-" are inclusive of straight chain groups and branched chain
groups and cyclic groups, e.g., cycloalkyl and cycloalkenyl. Unless
otherwise specified, these groups contain from 1 to 20 carbon
atoms, with alkenyl groups containing from 2 to 20 carbon atoms. In
some embodiments, these groups have a total of at most 10 carbon
atoms, at most 8 carbon atoms, at most 6 carbon atoms, or at most 4
carbon atoms. Lower alkyl groups are those including at most 6
carbon atoms. Examples of alkyl groups include haloalkyl groups and
hydroxyalkyl groups.
[0037] Unless otherwise specified, "alkylene" and "alkenylene" are
the divalent forms of the "alkyl" and "alkenyl" groups defined
above. The terms, "alkylenyl" and "alkenylenyl" are used when
"alkylene" and "alkenylene", respectively, are substituted. For
example, an arylalkylenyl group comprises an alkylene moiety to
which an aryl group is attached.
[0038] "Pharmaceutically acceptable" as used herein means that the
compound or composition is suitable for administration to a subject
to achieve the treatments described herein, without unduly
deleterious side effects in light of the severity of the disease
and necessity of the treatment.
Preparation of Hydrophobically Modified Phytoglycogen or
Glycogen-Type Materials
[0039] The inventors have developed a number of chemically modified
highly branched carbohydrate polymer prototypes. Some examples are:
octenylsuccinate hydroxyethyl phytoglycogen (OHEP),
octenylsuccinate hydroxypropyl phytoglycogen (OHPP),
octenylsuccinate hydroxypropyl phytoglycogen beta-dextrin (OHPPB),
propionate hydroxypropyl phytoglycogen (PHPP), acetate
hydroxypropyl phytoglycogen (AHPP), and propionate octenylsuccinate
hydroxypropyl phytoglycogen (POHPP). These new materials are
defined herein as "hydrophobically modified phytoglycogen or
glycogen-type (HMPGT)" materials. HMPGT materials belong to the
broader class of hydrophobic highly branched carbohydrate
polymers.
[0040] The name of each HMPGT is not binding due to the multiple
approaches with nomenclature. For example, octenylsuccinate
hydroxypropyl phytoglycogen (OHPP) can also be named as
octenylsuccinate polypropylene glycol phytoglycogen (OPPGP) or
octenylsuccinate polypropylene oxide phytoglycogen (OPPOP). The
general chemical nature of each HMPGT material is defined by the
approach in preparing them. Phytoglycogen or glycogen-type (PGT)
materials are used as the starting material for substitutions,
grafting, or conjugating. The PGT materials include: glycogen,
phytoglycogen, glycogen-type materials extracted from
microbiological, plant, or animal resources, and highly branched
biopolymers synthesized through genetic, chemical, physical, and
enzymatic approaches. For example, highly branched glucan molecules
synthesized by using starch branching enzymes belong to PGT
materials defined herein.
[0041] To the molecule of a PGT material, the first-step
substitution (modification) is conducted using a polyalkylene
glycol, alkylene oxide, or their combinations. This first-step
substitution can also be conducted using chains of polyethylene
glycol, polypropylene glycol, their mixtures, or their co-polymers.
In addition, the first-step substitution can be conducted using
other types of polymers. One structural outcome of this first-step
substitution is to form an accumulation of linear or branched
chains at the surface of PGT particulates. The accumulation of
these chains may form a layer at the surface of PGT particulates,
or may form other types of distribution pattern with PGT materials.
For example, the substitution may occur at both the external and
internal regions of PGT particulates, and the distribution can be
even or uneven based on the protocols used for this first-step
substitution reaction.
[0042] After the first-step substitution, the second-step
substitution (modification) is conducted to bring hydrophobic,
lipophilic, or amphiphilic moieties to the PGT-based particulates.
One purpose of this second-step substitution is to promote the
interactions between the PGT-based particulates and the hydrophobic
compounds, such as APIs (active pharmaceutical ingredients).
Accordingly, in this second step, the modified highly branched
carbohydrate formed after the first step (Step-1) is reacted with a
hydrophobic or amphiphilic group to provide a solubilizing agent.
The second-step substitution can be substitutions by
octenylsuccinate, acetate, propionate groups, or their
combinations, as well as the substitutions of other hydrophobic,
lipophilic, or amphiphilic groups. In some embodiments, the
hydrophobic or amphiphilic groups of the second step react with the
polyalkylene glycol attached to the PGT. Alternately, or in
addition, the hydrophobic or amphiphilic groups of the second step
react directly with the PGT itself.
[0043] The first-step (Step-1) substitution (modification) can be
carried out through a polymerization reaction using alkylene oxide
monomers (such as ethylene oxide or propylene oxide) or through a
grafting reaction such as PEGylation (i.e. grafting a chain segment
of polyethylene glycol). The degree of substitution (DS) of the
first-step substitution is defined as the molar ratio between the
monomers attaching to the particulates and the total glucosyl units
of PGT material. For example, if 5 mol of hydroxypropyl groups (one
hydroxypropyl group being generated from one propylene oxide) are
attached to a certain amount of PGT material that contains 10 mol
of glucosidic units, then DS is calculated as: DS=(5 mol)/(10
mol)=0.5. The DS value can be determined by various methods, such
as titration, NMR, HPLC, MS, colorimetric methods, and others.
Preferably, the first-step substitution DS is between 0.01 and
10,000.
[0044] The second-step (Step-2) substitution can be carried out
using various methods, such as reacting the PGT-based materials
with an anhydride (e.g. octenyl succinic anhydride, acetic
anhydride, propionic anhydride). For the second-step substitution,
the degree of substitution (DS) is defined as the molar ratio
between the attached hydrophobic, lipophilic, or amphiphilic groups
and the total glucosyl units of the PGT-based material. The DS
value can be determined by various methods, such as titration, NMR,
HPLC, MS, colorimetric methods, and others. In this invention, the
second-step substitution DS is between 0.01 and 10.
[0045] The reaction scheme of preparing octenylsuccinate
hydroxypropyl phytoglycogen (OHPP) is described in Scheme 1.
##STR00001##
[0046] As shown in Scheme 1, OHPP can be prepared using two steps
of reaction. In Step-1, phytoglycogen is activated using sodium
hydroxide and reacted with propylene oxide to form hydroxypropyl
phytoglycogen. In step-2, hydroxypropyl phytoglycogen is further
reacted with octenylsuccinic anhydride under alkaline conditions to
form octenylsuccinate hydroxypropyl phytoglycogen (OHPP). The OHPP
material is then purified and dried to yield solid. Where Scheme 1
shows that the octenylsuccinate group attaches to the hydroxypropyl
group, this does not exclude the possibility that the
octenylsuccinate group may also attached directly to
phytoglycogen.
Use of HMPGT Materials to Solubilize Hydrophobic Solute
Compounds
[0047] The primary usage of HMPGT materials, as a fundamentally
novel group of biomaterials, is to enhance the water-solubility of
hydrophobic solute compounds, such as poorly water-soluble active
pharmaceutical ingredients (APIs) or drug substances. For example,
HMPGT may significantly enhance the water solubility or dispersity
of BCS Class II and BCS Class IV drug substances. HMPGT materials
are acting as solubilizing agents. As defined earlier, a
solubilizing agent can increase the solubility of a solute
compound.
[0048] BCS means Biopharmaceutics Classification System. According
to BCS, drug substances or APIs can be classified in 4 classes:
[0049] Class I: high permeability, high solubility [0050] Class II:
high permeability, low solubility [0051] Class III: low
permeability, high solubility [0052] Class IV: low permeability,
low solubility.
[0053] As used herein, the term "solubility" indicates the
capability of a solute compound, such as API compounds or drug
substances to form stable, transparent or opaque dispersion in an
aqueous system. "Enhanced stability" can be associated with one or
multiple situations listed below: [0054] 1. Increased concentration
of the solute compound, such as APIs or other substances in aqueous
systems through increased equilibrium solubility. [0055] 2.
Increased dissolution rate. [0056] 3. Formation of more stable
supersaturated solution. [0057] 4. Formation of more stable
colloidal systems, such as micellar dispersions or emulsions
showing reduced phase separation, precipitation, or creaming over a
relevant period of time related to processing, storage, or
consumption. [0058] 5. Enhanced portion of particulates (in aqueous
systems) that are smaller than a defined size, such as 50, 100, or
500 nanometers.
[0059] For a solute compound, such as API or drug substances, as a
result of providing enhanced solubility, one or more of the
beneficial outcomes listed below may be provided:
[0060] 1. Increased bioavailability of API or drug substances
[0061] 2. Increased bioaccessibility of API or drug substances
[0062] 3. Increased permeation of API or drug substances
[0063] 4. More convenient handling of dosage forms
[0064] 5. More convenient formulations
[0065] 6. Increased safety of drugs
[0066] 7. Reduced cost for producing and using formulations
[0067] The HMPGT and hydrophobic solute compound (e.g., API) can be
incorporated using any approach that is feasible, such as
extrusion, solvent (including water)-based spray drying, vacuum
drying, kneading, milling, blending, and/or other types of mixing
or incorporation procedures. The mixture of HMPGT and API can be in
the form of powder, granulated, solid, liquid, semi-liquid, gel,
film, etc. that is desirable for appropriate formulations or dosage
forms.
[0068] As a non-binding hypothesis to describe the effects of HMPGT
materials to interact and solubilize poorly water-soluble
(hydrophobic) or lipophilic APIs, the particulate structure of OHPP
and its interactions with API molecules are shown in FIG. 1. The
phytoglycogen forms a template (or a base) for grafting
hydroxyalkyl (e.g., hydroxypropyl (HP)) chains, on which the
hydrophobic or amphiphilic groups, such as octenyl succinate (OS),
are further attached. In this invention, the hydroxyalkyl chains
can also be polyalkylene glycol or polyalkylene oxide chains, such
as polyethylene glycol (or polyethylene oxide) chains, or
polypropylene glycol (or polypropylene oxide) chains.
[0069] In OHPP, both HP and OS groups are necessary for the
performance of nanoparticles: (1) OS groups enhance the
interactions between nanoparticles and hydrophobic API molecules,
and (2) HP groups may offer OS groups the physical flexibility
needed for effective interactions with API molecules. API molecules
not only interact with OS groups at the surface of nanoparticles,
but may also adsorb with the HP layer and possible PG
(phytoglycogen) core.
Highly Branched Carbohydrate Polymers
[0070] In this invention, highly branched carbohydrate polymers can
include highly branched alpha-D-glucans and other types of highly
branched carbohydrate polymers.
[0071] The term "highly branched alpha-D-glucan" (highly branched
.alpha.-D-glucan), as used herein, refers to a highly branched
polysaccharide formed from alpha-D-glucose molecules, such as
glycogen, phytoglycogen, amylopectin, or modified forms thereof. In
some embodiments, the polysaccharides are linked by alpha-D-1,4 and
alpha-D-1,6 glucosidic linkages. However, in other embodiments,
chemical modification (e.g., pyrodextrinization) can be used to
provide highly branched alpha-D-glucans including other types of
linkages, such as alpha-D-1,2 and alpha-D-1,3 linkages. The highly
branched alpha-D-glucan can be obtained, derived, or extracted from
a plant material, a microbe (e.g., bacterium), or a human or
non-human animal, or synthesized from glucose, glucans, or other
materials. In one example, the highly branched alpha-D-glucan can
be one from the group that comprises glycogen, phytoglycogen,
amylopectin, and/or modified forms thereof, such as with
modifications with octenyl succinate (OS) or polyethylene glycol
(PEG).
[0072] In addition to alpha-D-glucans, other types of highly
branched carbohydrate polymers can also be modified to provide
capability to increase the solubility of poorly water-soluble
compounds. The highly branched carbohydrate polymer can also be a
non-glucan highly branched material, such as gum Arabic or its
derivative, or arabinoxylan or its derivative. The carbohydrate
polymer can also be a synthesized material such as polydextrose or
its derivative. Furthermore, the carbohydrate polymer can be a
material that is a "hybrid," for example, the material formed
through covalent connections between two types of polysaccharide,
between a polysaccharide and a protein (or a lipid), or between a
polysaccharides and a monosaccharide (or a oligosaccharide).
[0073] As used herein, a highly branched carbohydrate polymer is a
carbohydrate polymer having a branch density of at least about 4%.
In some embodiments, the branch density of the highly branched
carbohydrate polymer can range from about 5% to about 30%. In other
embodiments, the branch density is at least 5%, at least 6%, at
least 7%, or at least 8%. In other embodiments, the branch density
can range for example, between about 7% to about 16%. For example,
the branch density of amylopectin can be about 4%-6%, and the
branch density of glycogen and phytoglycogen can be about 8%-11%.
For example, for glucans that contain only alpha-D-1,4 and
alpha-D-1,6 glucosidic linkages, branch density can be determined
by comparing the number of alpha-D-1,4 and alpha-D-1,6 glucosidic
linkages as follows: percentage branch density=the number of
alpha-D-1,6 glucosidic linkages/(the number of alpha-D-1,4
glucosidic linkages+the number of alpha-D-1,6 glucosidic
linkages)*100. In general, branch density is the percentage of the
number of branching points based on all glycosidic linkages in the
macromolecule.
[0074] For carbohydrate polymers or polysaccharides in general,
branch density is the percentage of the number of branching points
based on all glycosidic linkages in the macromolecule.
[0075] In some embodiments, the highly branched carbohydrate
polymer (e.g., highly branched alpha-D-glucan) has a dendritic or
dendrimer-like structure. In a dendritic or dendrimer-like
structure, the polysaccharide chains are organized globularly like
branches of a tree originating from a central location that acts as
a primer at the core of the structure.
[0076] The branch density of a carbohydrate polymer can be
determined by a number of methods, such as reducing end analysis,
NMR, and chromatographic analysis. See Shin et al., Journal of
Agricultural and Food Chemistry, 56: 10879-10886 (2008); Yao et
al., Plant Physiology, 136: 3515-3523 (2004); and Yun and Matheson,
Carbohydrate Research, 243: 307-321 (1993). Enzymatic treatment can
affect the branch density of alpha-D-glucan by creating or cleaving
alpha-D-1,4-glucosidic linkages and/or alpha-D-1,6-glucosidic
linkages. These enzymes can be alpha-amylase, beta-amylase,
debranching enzymes (e.g., pullulanase and isoamylase),
transglucosidase, amyloglucosidase, and the like. Other approaches,
such as acid or alkaline treatment, as well as oxidation can also
affect the branch density of alpha-D-glucans. In one example, the
highly branched alpha-D-glucan can be a single type of highly
branched alpha-D-glucan. Alternately, the highly branched
alpha-D-glucan can be a mixture that includes a plurality of
different highly branched alpha-D-glucans.
[0077] In some embodiments, the highly branched carbohydrate
polymer is a phytoglycogen. Phytoglycogen is a water-soluble,
glycogen-like alpha-D-glucan generated by plants. One of the
largest sources of phytoglycogen is the kernel of the maize mutant
sugary-1 (su1), a major genotype of sweet corn. The su1 mutation
leads to the deficiency of SU1, an isoamylase-type starch
debranching enzyme (DBE) (James et al., Plant Cell, 7: 417-429
(1995)). In the biosynthesis of starch, starch synthase, starch
branching enzyme and DBE work coordinately to produce starch
granules (Yao, "Biosynthesis of starch," Comprehensive
Glycoscience, edited by Hans Kamerling. Elsevier (2007)). It is
considered that a role of DBE is to trim abnormal branches that
inhibit the formation of starch crystals and granules. See Myers et
al. Plant Physiology, 122: 989-997 (2000) and Nakamura, Plant and
Cell Physiology, 43: 718-725 (2002). In the absence of DBE, the
highly branched phytoglycogen is formed to replace starch
granules.
[0078] Each phytoglycogen particle contains hundreds or thousands
of glucan chains forming a highly packed structure. The highly
branched structure of phytoglycogen results in its unusually high
molecular density in dispersion. In rice, the dispersed molecular
density of phytoglycogen is over 10 times that of starch (Wong et
al., Journal of Cereal Science, 37: 139-149 (2003)). The molecular
density of phytoglycogen from maize is around 1198 g/molnm.sup.3
compared with about 62 g/molnm.sup.3 for amylopectin of starch
(Huang & Yao, Carbohydrate Polymers, 83, 1665-1671 (2011)).
High density renders structural integrity of phytoglycogen and
allows for dense grafting of functional groups. While not fully
understood, it is likely that the phytoglycogen nanoparticles grow
from the non-reducing ends of glucan chains at the surface by
periodic branching and elongation of chains.
[0079] In some embodiments, the highly branched carbohydrate
polymer is a modified highly branched alpha-D-glucan that has been
subjected to the treatment of amyloglucosidase to reduce the
particle size. One example is that phytoglycogen is subjected to
amyloglucosidase to reduce its particle size from over 40 nm to
below 30 nm.
Modified Highly Branched Carbohydrate Polymers
[0080] In some embodiments, the highly branched carbohydrate
polymer is a modified highly branched carbohydrate polymer. A
modified highly branched carbohydrate polymer is a highly branched
carbohydrate polymer that has been modified by using chemical
approaches, enzymatic approaches, physical approaches, biological
approaches, or a combination of above. Through these modifications,
the highly branched carbohydrate polymer (e.g., highly branched
alpha-D-glucan) can have a different electrical charge, different
hydrophobicity, an altered molecular weight, increased or decreased
side chain length, a chemical or biochemical functional group, a
reduced or increased branch density, altered particle size, or a
combination thereof.
[0081] In some embodiments, the highly branched carbohydrate
polymer has been modified to include functional groups selected
from acetate, phosphate, octenyl succinate, succinate,
hydroxypropyl, hydroxyethyl, cationic groups such as those
containing quaternary ammonium cations (e.g. formed using
2,3-epoxypropyl trimethylammonium chloride, EPTAC, and
(3-chloro-2-hydroxypropyl) trimethylammonium chloride, CHPTAC),
carboxymethyl, polyethylene glycol (PEG, or polyethylene oxide),
polypropylene glycol (or polypropylene oxide), or a combination of
above.
[0082] In some embodiments, the highly branched carbohydrate
polymer can also be modified using bleaching, acid hydrolysis,
oxidation, pyrodextrinization, or a combination of above.
[0083] In some embodiments, the highly branched carbohydrate
polymer can also be treated using shear force, high pressure
processing, homogenization, hydrothermal processing, microwave,
radiation, dry heating, or a combination of above.
[0084] In some embodiments, the highly branched carbohydrate
polymer can be further treated by conjugating with bioactive or
functional groups or ligands such as antibody, antigen, aptamer,
protein, peptide, amino acid, cyclodextrin, saccharide, lipid,
nucleic acid and nucleotide, folic acid (or folate), dendrimer,
enzyme, fluorescent group or dye, magnetic group, metal ion, metal
nanoparticle, quantum dot, polymer and block co-polymer,
radioactive group, or a combination of above.
[0085] In some embodiments, highly branched carbohydrate polymers
can be modified using enzymes such as alpha-amylase, beta-amylase,
debranching enzymes (e.g., pullulanase and isoamylase),
transglucosidase, amyloglucosidase, protease, and the like, or a
combination of above.
[0086] In some embodiments, modification of highly branched
carbohydrate polymers can be performed using a combination of
enzymatic, physical, chemical, biological, or other methods
mentioned above. Modified highly branched carbohydrate polymers can
have different solubility characteristics, such as increased
solubility in non-aqueous solvents such as ethanol, and can have
solubility, the dissolution rate, and/or other properties
associated with its environment, such as pH, ionic strength,
temperature, biological environment, presence of magnetic field or
various types of radiation, or a combination of above.
[0087] Hydrophobically modified phytoglycogen or glycogen-type
(HMPGT) materials, hydrophobic highly branched alpha-D-glucans
(HHBG), hydrophobic highly branched polysaccharides (HHBP), and
hydrophobic highly branched carbohydrate polymers (HHBCP) are the
solubilizing agents described by the current invention. These
materials have potential to improve the water solubility of poorly
water-soluble compounds. Phytoglycogen or glycogen-type materials
are included within the scope of highly branched alpha-D-glucans.
The treatment of other highly branched polysaccharides and/or
highly branched carbohydrate polymers are largely the same as for
highly branched alpha-D-glucans, except that specific enzymes need
to be selected for achieving desirable enzymatic modifications of
specific carbohydrate polymer or polysaccharide.
Solute Compounds
[0088] In one aspect, the invention described herein provides
compositions for increasing the solubility of a hydrophobic solute
compound (also referred as solute compound). It should be noted
that the term "solute compound" is used herein as a convenient
label, but that the modified highly branched carbohydrate polymers
can be used for purposes other than increasing solubility, such as
the physical, chemical, or physicochemical stability of the solute
compound. Physical stability includes the stability of a solute
compound in terms of its amorphous form, crystal size, crystalline
structure or form (e.g. polymorphs), or a combination thereof.
Chemical stability includes the stability of a solute compound in
terms of its resistance to oxidation, reduction, chemical reaction,
structure change or degradation, or a combination thereof.
Physicochemical stability includes physical stability, chemical
stability, or a combination thereof.
[0089] A wide variety of different hydrophobic solute compounds can
be used. Many bioactive compounds are highly hydrophobic, meaning
that they are likely to be soluble in lipids (oils) and/or some
organic solvents, while being substantially insoluble in aqueous
solution. The lack of solubility of bioactive compounds in aqueous
solution is an important factor limiting their therapeutic
applications. The present invention provides a solubilizing agent
(modified highly branched carbohydrate polymers or polysaccharides)
having sufficient affinity to associate with these hydrophobic
solute compounds, while still remaining water soluble themselves.
In addition, the solubilizing agent in present invention may
increase the stability of the solute compound in the soluble
composition, a composition that includes at least one modified
highly branched carbohydrate polymer and at least one solute
compound.
[0090] In another aspect, some hydrophobic solute compounds, such
as griseofulvin, have strong crystalline structure. The
thermodynamically stable crystalline structure drives quick
transformation of amorphous form of compounds toward
crystallization, leading to a low stability of amorphous form. When
these compounds are associated with highly branched carbohydrate
polymer or it derivatives, the rate of crystallization can be
reduced. This will contribute to the increased stability and
solubility of the solute compounds. In other cases, some solute
compounds are easy to be oxidized or degraded, such as lemon oil
and vitamin E. When these compounds are associated with highly
branched carbohydrate polymer or its modified forms, the rate of
oxidation can be reduced.
[0091] In general, the hydrophobic solute compound can include any
one or combination of materials for which their improved solubility
or the dissolution rate in an aqueous solution (e.g., water) is
desirable. Due to their low solubility or low dissolution rate in
water, these compounds have limited accessibility and
bioavailability when used alone. The compositions of this invention
can therefore include at least one hydrophobic solute compound
having a water solubility and/or dissolution rate that is greater
than the water solubility and/or dissolution rate of the solute
compound in the absence of the highly branched carbohydrate polymer
or the modified form thereof. In some instances, the hydrophobic
solute compound can be a compound or a mixture of compounds
selected from the group consisting of nutrients, vitamins, drugs,
coloring agent, agrochemicals, pesticides, herbicides,
anti-oxidants, coloring agents, hormones, essential oils, extracts
from plants, Chinese medicine, animals or microbial organisms, and
combinations thereof.
[0092] Hydrophobic solute compounds can be categorized in a variety
of different manners. In some instances, the highly branched
carbohydrate polymer or the modified forms thereof can be used
together with relatively large solute compounds having a size from
about 10,000 daltons to about 100,000 daltons. In other
embodiments, the solute compound has a molecular weight or average
molecular weight less than about 10,000 Daltons. In further
embodiments, the solute compound has a molecular weight or average
molecular weight of less than about 1,000 daltons. In other
embodiments, the solute compound is a bioactive hydrophobic
compound. Examples of hydrophobic compounds include phytochemicals,
carotenoids, extracts from plants, animals, or microorganisms, and
drugs.
[0093] Phytochemicals include phenolic compounds such as catechins,
curcumin, quercetin, rutin, resveratrol, genistein, daidzcin, and
kacmpferol; and carotenoids, e.g., lycopene, beta-carotene, and
lutein.
[0094] Extracts from plant, animals, or microbial organisms (e.g.,
dietary supplements or medical extracts), include extracts from
grape seeds, pomegranate, olive leaves, Turmeric, green tea, black
tea, cocoa (cacao), insects, crustaceans, yeast, fungus, mushrooms,
ginseng, cloves, Purslane, Acanthopanax, Rubescens, Pucraria,
Ganoderma lucidum, Alisma, Medlar, Angelica, Gardenia, Honeysuckle,
Sophora japonica, Flavescens, Schisandra, Cassia seed, Salvia,
Radix, Epimedium, Licorice, Bupleurum, Pulsatilla, Houttuynia,
Coptis, Artemisia annua, Scutellaria, Codonopsis, Forsythia,
Camptotheca acuminate, and Andrographis paniculata.
[0095] The hydrophobic solute compounds of the invention can be an
active pharmaceutical ingredient (API, e.g., a drug) such as a
hydrophobic drug that is otherwise difficult to administer. Drugs
include antineoplastic agents, such as paclitaxel, camptothecin,
sagopilone, docetaxel, rapamycin, doxorubicin, daunorubicin,
idarubicin, epirubicin, capecitabine, mitomycin c, amsacrine,
busulfan, tretinoin, etoposide, chlorambucil, chlormethine,
melphalan, and benzylphenylurea compounds; steroidal compounds,
such as natural and synthetic steroids, and steroid derivatives,
such as cyclopamine; antiviral agents, such as aciclovir,
indinavir, lamivudine, stavudine, nevirapine, ritonavir,
ganciclovir, saquinavir, lopinavir, and nelfinavir; antifungal
agents, such as itraconazole, ketoconazole, miconazole,
oxiconazole, sertaconazole, amphotericin b, and griseofulvin;
antibacterial agents, such as quinolones, e.g., ciprofloxacin,
ofloxacin, moxifloxacin, methoxyfloxacin, pefloxacin, norfloxacin,
sparfloxacin, temafloxacin, levofloxacin, lomefloxacin, and
cinoxacin; antibacterial agents, such as penicillins, e.g.,
cloxacillin, benzylpenicillin, and phenylmethoxypenicillin;
antibacterial agents, such as aminoglycosides, e.g., erythromycin
and other macrolides; antitubercular agents, such as rifampicin and
rifapentine; and anti-inflammatory agents such as ibuprofen,
indomethacin, ketoprofen, naproxen, oxaprozin, piroxicam, and
sulindac.
[0096] In some embodiments, the hydrophobic solute compounds are
active pharmaceutical ingredients with low or poor water
solubility, such as acetaminophen, acetazolamide, albendazole,
amiodarone, amphotericin, atorvastatin, azithromycin, azathioprine,
bicalutamide, carbamazepine, carvedilol, cefdinir, cefprozil,
celecoxib, chlorpromazine, chlorothiazide, cisapride,
clarithromycin, clofazamine, clopidogrel, colistin, cyclosporine,
cyproterone, danazol, dapsone, diclofenac, diflunisal, diloxanide,
efavirenz, ezetimibe, fenofibrate, flurbiprofen, furosemide,
glibenclamide, glimepiride, glipizide, glyburide, griseofulvin,
haloperidol, hydrochlorothiazide, hydroxyzine pamoate, ibuprofen,
imatinib mesylate, irbesartan, isotretinoin, indinavir,
indomethacin, itraconazole, ivermectin, ketoconazole, ketoprofen,
lansoprazole, lamotrigine, linezolid, lopinavir, lovastatin,
loratadine, medroxyprogesterone acetate, meloxicam, metaxalone,
methylphenidate hydrochloride, modafinil, moxifloxacin
hydrochloride, mycophenolate mofetil, mebendazole, mefloquin,
nalidixic acid, naproxen, neomycin, nevirapine, nelfinavir,
nifedipine, niclosamide, nystatin, ofloxacin, olanzapine,
oxcarbazepine, oxycodone hydrochloride, oxaprozin, orlistat,
phenazopyridine, phenytoin, piroxicam, praziquantel, pioglitazone
hydrochloride, pyrantel, quetiapine, raloxifene, retinol, rifampin,
risperidone, ritonavir, rofecoxib, saquinavir, simvastatin,
sirolimus, spironolactone, sulfamethoxazole, sulfasalazine,
tacrolimus, tamoxifen, telmisartan, talinolol, terfenadine,
trimethoprim, valdecoxib, valsartan, valproic acid, and
warfarin.
[0097] In some embodiments, the hydrophobic solute compounds are
cell culture components, including but not limited to one or more
of following compounds: 6,7-ADTN HBr, R(-)-N-Allylnorapomorphine
HBr, p-Aminoclonidine HCl, (.+-.)-p-Aminoglutethimide,
R(+)-Atenolol, S(-)Atenolol, Butaclamol, Chloramphenicol,
4'-Chlordiazepam, Chlorthalidone, CNQX, Codeine sulfate, CV-1808,
8-Cylclopentyl-1,3-p-sulfophenylxanthine, Dexamethasone, Diazepam,
Digoxin, 7,9-Dimethyluric acid, 7,9-Dimethylxanthine,
3,5-Dinitrocatechol, 1,3-Dipropyl-8-p-sulfophenylxanthine, DNQX,
(S)-ENBA, Estradiol, FG-7142, Furosemide, L-Glutamic acid HCl,
L-Glutamic acid diethyl ester HCl, Glutethimide, Haloperidol,
Hexahydro-sila-difenidol HCl, Hexahydro-sila-difenidol HCl,
p-fluoro analog, Hydrocortisone, 6-Hydroxydopamine HBr,
3-Hydroxymethyl-.beta.-carboline, Indomethacin, lodotubercidin,
Isobutylmethylxanthine, (-)-MDO-NPA HCl, Methotrexate, 2-Methylthio
ATP, Naltrindole HCl, Quabain, Papaverine HCl,
2-Phenylaminoadenosine, R(-)-PIA, S(+)-PIA, Pirenperone,
Prochlorperazine, Progesterone, DL(.+-.)-Propranolol,
(-)-Quisqualic acid, Ranitidine HCl, Ro 15-4513, Ro 20-1724, PDE
inhibitor, Ro 41-0960, COMT inhibitor, Ryanodine, SKF-83566 HCl,
Spiperone HCl, Sulpride, Testosterone, Tetrahydrocannabinol,
Veratridine, Vitamin A, Vitamin D.
[0098] In some embodiments, the hydrophobic solute compound is a
phenolic compound. Phenolic compound are substances that have one
or more aromatic rings and bear one or more hydroxyl substituents
on the ring, including functional derivatives such as esters,
methyl ethers, glycosides and other derivatives that are apparent
to those skilled in the art. Included in the definition of
phenolics are polyphenols having complex substitution patterns,
compounds having condensed rings, and phenolics containing one or
more amine moieties and/or carboxylic acid moieties. Examples of
naturally occurring phenolic compounds include, but are not limited
to: bergaptol, caffeic acid, capsaicin, coumarin, daidzein,
2,5-dihydroxybenzoic acid, ferulic acid, flavonoids, glycitein
(isoflavone), 4-hydroxycinnamic acid, 4-hydroxycoumarin,
isopimpinellin, resveratrol, synapic acid, vanillic acid, and
vanillin.
[0099] Synthetic and naturally-occurring phenolic moieties, some of
which may contain amine groups, carboxylic acid groups, or
aminoacids, are part of many drugs. Examples of these medicinal
phenolic compounds include acenocoumarol, acetarsol, actinoquinol,
adrenalone, alibendol, aminosalicylic acids, amodiaquine, anethole,
balsalazide, bamethan, benserazide, bentiromide, benzarone,
benzquinamide, bevantolol, bifluranol, buclosamide, bupheniode,
chlorobiocin, chlorotrianisene, chloroxylenol, cianidanol,
cinepazide, cinitapride, cinepazide, cinmetacin, clebopride,
clemastine, clioquinol, coumermycin A1, cyclovalone, cynarine,
denopamine, dextroythyroxine, diacerein, dichlorophen, dienestrol,
diethylstilbestrol, diflunisal, diiodohydroxyquinoline, dilazep,
dilevalol, dimestrol, dimoxyline, diosmin, dithranol, dobutamine,
donepezil, dopamine, dopexamine, doxazosin, entacapone, epanolol,
epimestrol, epinephrine, estradiol valerate, estriol, estriol
succinate, estrone, etamivan, etamsylate, ethaverine,
ethoxzolamide, ethyl biscoumacetate, etilefrine, etiroxate,
exalamide, exifone, fendosal, fenoldopam mesilate, fenoterol,
fenoxedil, fenticlor, flopropione, floredil, fluorescein,
folescutol, formoterol, gallopamil, gentistic acid, glaziovine,
glibenclamide, glucametacin, guajacol, halquinol, hexachlorophene,
hexestrol, hexobendine, hexoprenaline, hexylresorcinol,
hydroxyethyl salicylate, hydroxystilbamidine isethionate,
hymecromone, ifenprodil, indometacin, ipriflavone, isoetarine,
isoprenaline, isoxsuprine, itopride hydrochloride, ketobemidone,
khellin, labetalol, lactylphenetidin, levodopa, levomepromazine,
levorphanol, levothyroxine, mebeverine, medrylamine, mefexamide,
mepacrine, mesalazine, mestranol, metaraminol, methocarbamol,
methoxamine, methoxsalen, methyldopa, midodrine, mitoxantrone,
morclofone, nabumetone, naproxen, nitroxoline, norfenefrine,
normolaxol, novobiocin, octopamine, omeprazole, orciprenaline,
oxilofrine, oxitriptan, oxyfedrine, oxypertine, oxyphenbutazone,
oxyphenisatin acetate, oxyquinoline, papaverine, paracetanol,
parethoxycaine, phenacaine, phenacetin, phenazocine,
phenolphthalein, phenprocoumon, phentolamine, phloedrine,
picotamide, pimobendan, prenalterol, primaquine, progabide,
propanidid, protokylol, proxymetacaine, raloxifene hydrochloride,
repaglinide, reproterol, rimiterol, ritodrine, salacetamide,
salazosulfapyridine, salbutamol, salicylamide, salicylic acid,
salmeterol, salsalate, sildenafil, silibinin, sulmetozin,
tamsulosin, terazosin, terbutaline, tetroxoprim, theodrenaline,
tioclomarol, tioxolone, ca-tocopherol (vitamin E), tofisopam,
tolcapone, tolterodine, tranilast, tretoquinol, triclosan,
trimazosin, trimetazidine, trimethobenzamide, trimethoprim,
trimetozine, trimetrexate glucuronate, troxipide, verapamil,
vesnarinone, vetrabutine, viloxazine, warfarin, xamoterol.
[0100] In other embodiments, the hydrophobic solute compounds can
be essential oils as crude or purified extracts of plants,
individual compounds or their mixtures, and/or their corresponding
synthetic substances. For example, thymol is a component of thyme
oil. The essential oils can be agar oil, ajwain oil, angelica root
oil, anise oil, asafoetida, balsam oil, basil oil, bay oil,
bergamot oil, black pepper essential oil, birch, camphor, cannabis
flower essential oil, caraway oil, cardamom seed oil, carrot seed
oil, cedarwood oil, chamomile oil, calamus root oil, cinnamon oil,
cistus species, citronella oil, clary sage, clove leaf oil, coffee,
coriander, costmary oil, costus root, cranberry seed oil, cubeb,
cumin oil/black seed oil, cypress, cypriol, curry leaf, davana oil,
dill oil, elecampane, eucalyptus oil, fennel seed oil, fenugreek
oil, fir, frankincense oil, galangal, galbanum, geranium oil,
ginger oil, goldenrod, grapefruit oil, henna oil, helichrysum,
hickory nut oil, horseradish oil, hyssop, idaho tansy, jasmine oil,
juniper berry oil, Laurus nobilis, lavender oil, ledum, lemon oil,
lemongrass, lime, Litsea cubeba oil, mandarin, marjoram, melaleuca
see tea tree oil, melissa oil (lemon balm), Mentha arvensis
oil/mint oil, mountain savory, mugwort oil, mustard oil, myrrh oil,
myrtle, neem oil, neroli, nutmeg, orange oil, oregano oil, orris
oil, palo santo, parsley oil, patchouli oil, perilla essential oil,
peppermint oil, petitgrain, pine oil, ravensara, red cedar, roman
chamomile, rose oil, rosehip oil, rosemary oil, rosewood oil, sage
oil, sandalwood oil, sassafras oil, savory oil, schisandra oil,
spearmint oil, spikenard, spruce oil, star anise oil, tangerine,
tarragon oil, tea tree oil, thyme oil, tsuga, turmeric, valerian,
vetiver oil, western red cedar, wintergreen, yarrow oil,
ylang-ylang, zedoary.
[0101] In a preferred embodiment, the hydrophobic solute compound
is a bioactive hydrophobic compound selected from one or more of a
carotenoid, a curcuminoid, a flavonoid, a sterol, a phytosterol, a
saponin, an aglycone, or an algycone of a saponin (i.e., a
sapogenin). In a further embodiment, the solute compound can be
selected from the group consisting of curcumin, quercetin,
resveratrol, thymol, paclitaxel, ibuprophen, and griseofulvin.
[0102] In some embodiments, the solute compounds are hydrophobic
vitamins, such as Vitamin A, Vitamin E, Vitamin D, and Vitamin
K.
[0103] In some embodiments, the solute compounds are hydrophobic
colorants, such as carotenoids, lutein, carmine, turmeric, cacao,
annatto (bixin), paprika, hematoxylin, anthocyanins, lac dye,
chlorophyllin, cochineal, lycopene.
Soluble Composition
[0104] In the present invention, a soluble composition is a
combination of at least one solubilizing agent with at least one
solute compound. A soluble composition realizes increased
solubility of the soluble compound(s) in water-containing solvent
and allows the preparation of aqueous solutions of a wide variety
of concentrations. As the concentrated solutions can be diluted
with an aqueous medium in any proportion and over a wide range of
pH conditions without separation or precipitation of the
hydrophobic compound, the solubility of the compound is maintained
under physiological conditions, for example after an oral or
parenteral administration of the composition. This normally results
in an improved bioavailability of the solute compound.
[0105] The soluble compositions of the present invention can be
easily incorporated into pharmaceutical, nutraceutical, medical, or
cosmetic formulations in which the solute compound shows improved
bioavailability. Such formulations may further contain additional
active ingredients and/or a pharmaceutically or cosmetically
acceptable additives or vehicles, including solvents, surfactants,
adjuvants, texture agents, bulking agents, excipients, sweeteners,
fillers, colorants, flavoring agents, lubricants, binders,
moisturizing agents, preservatives and mixtures thereof.
Collectively, these additional formulation materials can be
referred to as the pharmaceutically acceptable carrier.
"Pharmaceutically acceptable" as used herein means that the carrier
is suitable for administration to a subject for the methods
described herein, without unduly deleterious side effects. The
formulations may have a form suitable for a topical (e.g., a cream,
lotion, gel, ointment, dermal adhesive patch), oral (e.g., a
capsule, tablet, caplet, granulate, powder, liquid), or parenteral
(e.g., suppository, sterile solution) administration. Among the
acceptable vehicles and solvents that may be employed for
administration by injection are water, mildly acidified water,
Ringer's solution and isotonic sodium chloride solution.
[0106] In other embodiments, the soluble compositions including a
solute compound and a modified highly branched carbohydrate polymer
can be incorporated into other types of formulations. Examples of
these additional formulations include foods and beverages, food
supplements, cell culture, agrochemicals such as fertilizers and
pesticides, paint and coating, and the like. The formulation of
such nutritional, agricultural, or chemical formulations is known
to those skilled in the art.
[0107] According to the present invention, soluble compositions
that contain bioactive hydrophobic compounds may be administered to
a warm-blooded animal, particularly a human, in need of the
prophylaxis or therapy. The dose of a bioactive hydrophobic
compound and the corresponding dose of its soluble composition
together with modified highly branched carbohydrate polymer for
treating diseases or disorders will vary upon the manner of
administration, the age, sex, the body weight of the subject, and
the condition being treated, and will be ultimately decided by the
attending physician or veterinarian. Such an amount of the
bioactive compound in the form of its water-soluble composition as
determined by the attending physician or veterinarian is referred
to herein as a "therapeutically effective amount".
[0108] The mass ratio of solute compound to modified highly
branched carbohydrate polymer can vary from about 100:1 to about
1:1000. The ratio of solute compound to modified highly branched
carbohydrate polymer can vary depending on the type of composition
being provided. For example, in compositions intended to stabilize
a solute compound in dry form, a mass ratio ranging from about
100:1 to about 1:50 of solute compound to modified highly branched
carbohydrate polymer can be used, with a mass ratio ranging from
about 2:1 to about 1:20 being preferred. Alternately, in
compositions for increasing the solubility of solute compound, a
lower ratio of solute compound to modified highly branched
carbohydrate polymer can be used. For example, for a soluble
composition, a mass ratio ranging from about 10:1 to about 1:1000
of solute compound to carbohydrate polymer can be used, with a mass
ratio ranging from about 1:1 to about 1:50 being preferred. The
lower limit of the mass ratio is not critical, and the modified
highly branched carbohydrate polymer can be used in any excess.
However, this is not desirable in some applications, since
increasing the amount of the modified highly branched carbohydrate
polymer decreases the concentration of the active ingredient in the
composition and in its aqueous solutions.
Use of Modified Highly Branched Carbohydrate Polymers to Increase
Solubility, Dissolution Rate, and/or Stability
[0109] Combination of the solubilizing agent, that is, highly
branched carbohydrate polymers or modified forms thereof with the
solute compound provides a variety of benefits. In some
embodiments, the invention provides a method of increasing the
solubility, the dissolution rate, and/or stability of a solute
compound by combining the solute compound with an effective amount
of the highly branched carbohydrate polymer.
[0110] The present disclosure provides a method of increasing the
solubility and/or the dissolution rate of a solute compound. The
method includes the steps of combining an effective amount of at
least one highly branched carbohydrate polymer, or a modified form
thereof, with a solvent, combining the solute compound with a
second solvent, and adding the two together. In some embodiments,
the solute compound and the highly branched carbohydrate polymer
are first combined, and are then added to the solvent. However, the
method need not follow the order in which these steps are
described. In other words, in some embodiments, it may be
preferable to add the solute compound to a solvent, and then add
the highly branched carbohydrate polymer. The increased solubility
is exhibited once the solute compound has been placed together with
the highly branched carbohydrate polymer, in a process that
involves the use of a solvent or no solvent. The solvent can be a
relatively polar solvent, and in some embodiments is an aqueous
solvent (e.g., water), and in some embodiments is a mixture of
aqueous and non-aqueous solvent. As described herein, addition of
the highly branched carbohydrate polymer to the solute compound
results in the solute compound becoming associated or enmeshed in
the branches of the carbohydrate polymer so that the solute
compound is solubilized along with the highly branched carbohydrate
polymer.
[0111] In some embodiments, to achieve enhanced solubility and/or
dissolution rate of solute compounds, a solvent is not necessary
for combining a solute compound with a highly branched carbohydrate
polymer or its modified form, since this highly branched
carbohydrate polymer or its modified form can interact, dissolve,
or adsorb solute compounds without the use of a solvent. The
processing for such a non-solvent combination can be assisted with
extrusion, pressing, homogenization, grinding, rolling, kneading,
ultra-sonication, or a combination of above.
[0112] Use of the highly branched carbohydrate polymer (e.g.,
phytoglycogen) or its modified forms can increase the solubility of
the solute compounds to a varying degree, depending on the
particulars of the solute compound, the highly branched
carbohydrate polymer or its modified forms, and the solution in
which the solute compound is placed. For example, in some
embodiments the method increases the solubility of the solute
compound by at least about a factor of two relative to the
solubility of the solute compound in the absence of the highly
branched carbohydrate polymer. In other words, in some instances,
the solute compound can have a solubility that is at least two
times greater than the solubility of the solute compound in the
absence of a highly branched carbohydrate polymer. In other
instances, the solute compound can have a solubility that is at
least five times greater than the solubility of the solute compound
in the absence of a highly branched carbohydrate polymer. In
further instances, the solute compound can have a water solubility
that is at least ten times greater than the solubility of the
solute compound in the absence of the highly branched carbohydrate
polymer, and in yet further embodiments, the solubility of the
solute compound is at least one hundred times greater when combined
with the highly branched carbohydrate polymer.
[0113] Phenolic compounds are one type of solute compound whose
solubility is significantly enhanced by highly branched
carbohydrate polymers or their modified forms. The present
invention is capable of increasing the solubility of some phenolic
compounds by at least ten times compared with their solubility in
the absence of the highly branched carbohydrate polymers. For
example, use of OHPP can increase the solubility of curcumin in
aqueous solution by at least 100 times, and can increase the
solubility of resveratrol in aqueous solution by at least 10
times.
[0114] In other embodiments, a method of increasing the stability
of a solute compound is provided. The method includes the steps of
adding an effective amount of at least one highly branched
carbohydrate polymer, or a modified form thereof, to the solute
compound and combining the solute compound with a solvent. As with
the methods for increasing solubility, the steps of this method can
be carried out in any order. The solute compound complexed with the
highly branched carbohydrate polymer or its modified forms thereof
is more resistant to crystallization, oxidation, reduction,
structure change, deterioration and degradation, enzyme reaction,
chemical reaction, or a combination thereof, than the solute
compound in the absence of a highly branched carbohydrate polymer.
In addition, because crystallization lowers the solubility and/or
dissolution rate of solute compounds, stabilization of the solute
compounds in a non-crystallized form improves solubility and/or
dissolution rate. Compositions including a solute compound and the
highly branched carbohydrate polymer show an excellent stability
over long periods of time, in one embodiment, for over a month in
room temperature, in another embodiment, for over one year.
[0115] In some embodiments, for enhanced stability of solute
compounds, a solvent may not be necessary for combining a solute
compound with an HMPGT material that can interact, dissolve, or
adsorb solute compounds. The processing for such a non-solvent
combination can be extrusion, pressing, homogenization, grinding,
rolling, kneading, ultra-sonication, or a combination of above.
Preparation of Soluble Compositions that Contain Solute Compounds
and HMPGT Materials
[0116] Another aspect of the invention involves methods for
preparing a soluble composition. In one embodiment, the method
includes dissolving the hydrophobic solute compound in a solvent to
form a solution; mixing the solution with the HMPGT material, or a
modified form thereof; and removing the solvent to obtain the
soluble composition. In some embodiments, the solvent is a mixture
of non-aqueous solvent and aqueous solvent.
[0117] In another embodiment, the method for preparing a soluble
composition includes the steps of dissolving or dispersing at least
one hydrophobic solute compound in a first solvent to form a first
solution or dispersion; dissolving or dispersing at least one HMPGT
material or a modified form thereof in a second solvent to form a
second solution or dispersion; mixing the first and second
solutions or dispersions together to form a mixture; and removing
the solvent from the mixture to obtain a composition; wherein the
water solubility of the solute compound in the composition is
greater than the water solubility of the hydrophobic solute
compound in the absence of the at least one HMPGT material or a
modified form thereof. In some embodiments, the first solvent can
be an aqueous solvent; in some embodiments, the first solvent can
be a non-aqueous solvent; in some embodiments, the first solvent
can include a mixture of non-aqueous solvent and an aqueous
solvent. In further embodiments, the second solvent can be an
aqueous solvent; in some embodiments, the second solvent can be a
non-aqueous solvent; in some embodiments, the second solvent can
include a mixture of a non-aqueous solvent and an aqueous
solvent.
[0118] In other embodiment, the method for preparing a soluble
composition includes the steps of combining at least one
hydrophobic solute compound with at least one HMPGT material or a
modified form thereof. The combination can be in a solvent, or
without any solvent.
[0119] In some embodiments, the solvent is a non-aqueous solvent.
Examples of non-aqueous solvents can be selected from the group
consisting of pentane, cyclopentane, hexane, cyclohexane; benzene;
toluene; 1,4-dioxane, chloroform, diethyl ether, dichloromethane,
tetrahydrofuran, ethyl acetate, acetone, dimethylformamide,
acetonitrile, dimethyl sulfoxide, formic acid, n-butanol,
isopropanol, n-propanol, ethanol, methanol, acetic acid, and
combinations thereof. In some embodiments, the solvent can be a
non-aqueous solvent. In some embodiments, the solvent can include a
mixture of non-aqueous solvent and an aqueous solvent.
[0120] In some embodiments, the soluble composition including the
hydrophobic solute compound and the HMPGT material or a modified
form thereof can be prepared with additional processing steps. For
example, in some embodiments, the HMPGT material is derived or
extracted from a plant source, an animal source, or a microbial
source, or synthesized, or a combination thereof. In additional
embodiments, preparation of the soluble composition further
includes the step of processing the mixture by kneading, extrusion,
homogenization, ultrasonic, high-pressure treatment, high-speed
treatment, microwave treatment, radiation treatment, heat
treatment, or a combination thereof. In yet further embodiments,
the method includes removing the solvent from the mixture by spray
drying, vacuum drying, freeze drying, drum drying, heat drying,
extrusion, supercritical extraction, or a combination thereof.
[0121] When combining hydrophobic solute compounds with HMPGT
materials, it can sometimes be challenging to find a single solvent
in which both carrier and solute compound are soluble. DMSO is a
particularly effective solvent in this regard, but it can be
difficult to remove DMSO after complexation. In these situations,
it may be preferable to prepare a form of HMPGT material that is
soluble in ethanol, acetone, or this type of low polar or non-polar
solvent. For example, phytoglycogen has been modified into
phytoglycogen octenyl succinate (PG-OS), which can be dissolved in
non- or low-polarity solvents. To further improve the solubility of
carbohydrate polymer, polyethylene glycol (PEG) chains can be added
on PG-OS, thus generating PG-OS-PEG. This new material has much
enhanced solubility than PG-OS. In another example, phytoglycogen
can be modified to generate OHPP which is soluble in both water and
ethanol.
[0122] In some embodiments, a solvent is not necessary for
combining a solute compound with a HMPGT material or its modified
form, since this HMPGT material or its modified form can interact,
dissolve, or adsorb solute compounds without the use of a solvent.
The processing for such a non-solvent combination can be assisted
with blending, extrusion, pressing, tableting, homogenization,
grinding, rolling, kneading, ultra-sonication, or a combination of
above.
[0123] The present invention is illustrated by the following
examples. It is to be understood that the particular examples,
materials, amounts, and procedures are to be interpreted broadly in
accordance with the scope and spirit of the invention as set forth
herein.
EXAMPLES
Example 1: Preparation of Octenylsuccinate Hydroxyethyl
Phytoglycogen (OHEP)
[0124] Ten grams of phytoglycogen (PG) was dispersed in 60 g
deionized water. Forty grams sodium hydroxide (NaOH) was dissolved
in 100 g deionized water. The PG dispersion and NaOH solutions were
mixed and added in a 2-liter glass reactor. The temperature was
adjusted to 4.degree. C. and N.sub.2 gas was bubbled into the
solution (till the end of reaction). Cold (ice-water preserved)
ethylene oxide (ETO) 270 ml was added in the dispersion over the 72
h reaction, with 90 mL added within each 24 h. After each addition
of ETO, the system was allowed to stay at 4.degree. C. for 15 min,
10.degree. C. for 20 min, and the temperature was increased to
30.degree. C. before next addition of ETO.
[0125] After 72 h reaction, the reactant was neutralized with
acetic acid (HAc) and then subjected to ultrafiltration (MWCO 300
kD, Centramate, Pall Life Science) to remove small molecules. For
each of 10 cycles of ultrafiltration, the volume of product was
reduced to 1/2 and then added with deionized water to reach its
original volume. The permeated liquid was discarded. The final
product of ultrafiltration (as retentate) was considered as the
dispersion of purified hydroxyethyl phytoglycogen (HEP).
[0126] Half of the purified HEP dispersion was used for the
grafting of octenyl succinate group. To carry out the reaction, the
HEP dispersion was adjusted to pH 8.5-9.0 using NaOH. To the
dispersion, 6 g octenyl succinic anhydride (OSA) was added in 4 h.
After 15 h from the OSA addition, the reaction was terminated
through adjusting to pH6.0. The reactant was purified using
ultrafiltration to collect the dispersion of octenylsuccinate
hydroxyethyl phytoglycogen (OHEP). The OHEP dispersion was
lyophilized (freeze-dried) to collect OHEP solid.
Example 2: Preparation of Octenylsuccinate Hydroxyethyl
Phytolycogen (OHEP)
[0127] Fifty grams of phytoglycogen (PG) was dispersed in 300 g
deionized water. One hundred and fifty grams sodium hydroxide
(NaOH) was dissolved in 300 g deionized water. The PG dispersion
and NaOH solutions were mixed and added in a 2-liter glass reactor.
The temperature was adjusted to 4.degree. C. and N.sub.2 gas was
bubbled into the solution (till the end of reaction). Cold
(ice-water preserved) ethylene oxide (ETO) 1,200 mL was added in
the dispersion over the 72 h reaction, with 400 mL added within
each 24 h. After each addition of ETO, the system was allowed to
stay at 4.degree. C. for 15 min, 10.degree. C. for 20 min, and the
temperature was increased to 30.degree. C. before next addition of
ETO.
[0128] At the point of 72 h, reactant was collected and neutralized
with acetic acid, and then subjected to ultrafiltration (MWCO 300
kD) to obtain the dispersion of purified HEP.
[0129] Four fifth of the purified HEP dispersion was adjusted to pH
8.5-9.0 using NaOH. To the dispersion, 60 g octenyl succinic
anhydride (OSA) was added in 4 h. After 15 h from the last OSA
addition, the reaction was terminated through adjusting to pH 6.0.
The reactant was purified using ultrafiltration to collect the
dispersion of octenylsuccinate hydroxyethyl phytoglycogen (OHEP).
The OHEP dispersion was lyophilized to collect OHEP solid.
Example 3: Preparation of Octenylsuccinate Hydroxypropyl
Phytoglycogen (OHPP)
[0130] Fifty grams of phytoglycogen (PG) was dispersed in 300 g
deionized water. One hundred and fifty grams sodium hydroxide
(NaOH) was dispersed in 300 g deionized water. The PG dispersion
and NaOH solutions were mixed, heated in boiling water bath for 1
h, and then added in a 2-liter glass reactor. The temperature was
adjusted to 10.degree. C. and N.sub.2 gas was bubbled into the
solution for 30 min. To the PG dispersion, propylene oxide 250 mL
was added and the temperature was increased to 20.degree. C. for
the reaction to proceed for 15 h. The reactant was then collected
and neutralized with acetic acid, and then subjected to
ultrafiltration (MWCO 300 kD) to obtain the dispersion of purified
hydroxypropyl phytoglycogen (HPP).
[0131] Half of the purified HPP dispersion was used for grafting
octenyl succinate group. Another half of purified HPP dispersion
was subjected to a second round of reaction with 125 mL propylene
oxide. After reaction, the product was purified using
ultrafiltration.
[0132] Each of the purified HPP dispersions collected from the
first and second batches was adjusted to pH 8.5-9.0. To each
dispersion, 30 g octenyl succinic anhydride (OSA) was added to
prepare octenylsuccinate hydroxypropyl phytoglycogen. The reactants
generated were subjected to ultrafiltration and lyophilization to
collect the solid product of octenylsuccinate hydroxypropyl
phytoglycogen (OHPP).
Example 4: Preparation of Phytolycogen I-Dextrin (PBD) and OHPPBD
(Octenylsuccinate Hydroxypropyl Phytolycogen Beta-Dextrin)
[0133] One hundred grams of PG was dispersed in 500 mL sodium
acetate (NaAc) buffer (pH 6.0, 50 mM). To this dispersion, 1 mL
barley 0-amylase (28,400 U/mL, Megazyme) was added. The reaction
was carried out 50.degree. C. for 24 h in a shaking water bath.
Thereafter, the reactant was added into 2 L ethanol to terminate
the reaction and precipitate hydrolyzed PG (PG beta-dextrin). The
precipitated solid was repetitively washed using 80% ethanol,
dehydrated using pure ethanol, filtered, and hood-dried to collect
solid of PG beta-dextrin (PBD).
[0134] The procedure to prepare OHPPBD using PBD was the same as
that for preparing OHPP using PG. Briefly, PBD dispersed in NaOH
solution was added with propylene oxide, and the reaction was
allowed to proceed for 24 h. Thereafter, the reactant was
neutralized and subjected to ultrafiltration to purify
hydroxypropyl phytoglycogen beta-dextrin (HPPBD). The purified
HPPBD dispersion was added with propylene oxide for additional
substitution for 24 h, which was followed by neutralization and
ultrafiltration to purify HPPBD generated. Thereafter, the purified
HPPBD dispersion was added with octenyl succinic anhydride, and the
product generated was subjected to ultrafiltration and
lyophilization to obtain the solid of octenylsuccinate
hydroxypropyl phytoglycogen beta-dextrin (OHPPBD).
Example 5: Preparation of Propionate Hydroxypropyl Phytoglycogen
(PHPP), Acetate Hydroxypropyl Phytoglycogen (AHPP), and Propionate
Octenylsuccinate Hydroxypropyl Phytoglycogen (POHPP)
[0135] The procedure of preparing hydroxypropyl phytoglycogen (HPP)
was the same as described in earlier examples. Ultrafiltration was
used to obtain purified HPP dispersion.
[0136] To prepare PHPP, propionic anhydride was added to the HPP
dispersion (pH 8.5-9.0, 40.degree. C.), and the substitution
reaction was allowed to proceed for 24 h. The product generated was
subjected to neutralization, ultrafiltration, and lyophilization to
collect the PHPP solid.
[0137] To prepare AHPP, acetic anhydride was added to the HPP
dispersion (pH 8.5-9.0, 40.degree. C.), and the substitution
reaction was allowed to proceed for 24 h. The product generated was
subjected to neutralization, ultrafiltration, and lyophilization to
collect the AHPP solid.
[0138] To prepare POHPP, both propionic anhydride and octenyl
succinic anhydride were added to the HPP dispersion (pH 8.5-9.0,
40.degree. C.), and the substitution reaction was allowed to
proceed for 24 h. The product generated was subjected to
neutralization, ultrafiltration, and lyophilization to collect the
POHPP solid.
Example 6: Increase of API Solubility Through their Complexation
with OHPP
[0139] The performances of HMPGT, such as OHPP to improve the
solubility of a number of APIs were highly effective. Below are
examples with a number of APIs: niclosamide, paclitaxel, docetaxel,
celecoxib, itraconazole, griseofulvin, and curcumin.
Example 6-1: Preparation of OHPP
[0140] Fifty grams of phytoglycogen (PG) was dispersed in 300 g
deionized water. One hundred and fifty grams sodium hydroxide
(NaOH) was dispersed in 300 g deionized water. The PG dispersion
and NaOH solutions were mixed, heated in boiling water bath for 1
h, and then added in a 2-liter glass reactor. The temperature was
adjusted to 10.degree. C. and N.sub.2 gas was bubbled into the
solution for 30 min. To the PG dispersion, propylene oxide 250 mL
was added and the temperature was increased to 20.degree. C. for
the reaction to proceed for 15 h. The reactant was then collected
and neutralized with acetic acid, and then subjected to
ultrafiltration (MWCO 300 kD) to obtain the dispersion of purified
hydroxypropyl phytoglycogen (HPP). The purified HPP dispersion was
then subjected to a second round of reaction with 250 mL propylene
oxide. After reaction, the product was purified using
ultrafiltration.
[0141] The purified HPP dispersion was adjusted to pH 8.5-9.0 using
NaOH, and 65 g octenyl succinic anhydride (OSA) was added to
prepare octenylsuccinate hydroxypropyl phytoglycogen. The reactant
generated was subjected to ultrafiltration and lyophilization to
collect the solid product of octenylsuccinate hydroxypropyl
phytoglycogen (OHPP).
[0142] The OHPP materials generated using this procedure were used
in a number of experiments, including DS determination using NMR,
API incorporations, solubility evaluations, caco-2 monolayer
permeation, and anti-cancer efficacy evaluations.
Example 6-2: Solubility of Niclosamide, with API/Excipient Ratio of
1/3
[0143] One part of niclosamide was physically incorporated with 3
parts of OHPP, and the final product was in solid form. The
combined material between niclosamide and OHPP is termed as
"niclosamide-OHPP complex", "Nic-OHPP complex", or "Nic-OHPP" in
the present invention. Similarly the physically combined material
between niclosamide and HPMCAS is termed as "niclosamide-HPMCAS
complex", "Nic-HPMCAS complex", or "Nic-HPMCAS"; the physically
combined material between niclosamide and Soluplus (BASF) is termed
as "niclosamide-Soluplus complex", "Nic-Soluplus complex", or
"Nic-Soluplus".
[0144] Hydroxypropyl methylcellulose acetate succinate (HPMCAS) was
developed earlier as an enteric film coating because it is
insoluble in acidic gastric fluid, but may swell and dissolve in
the small intestine. Recently, it has been used to improve the
solubility of poorly water-soluble APIs.
[0145] Soluplus (Soluplus.RTM., BASF) was developed to form solid
dispersions with poorly soluble drug substances to improve their
solubility and bioavailability. Soluplus is a synthetic polymer
with an amphiphilic chemical structure, allowing it to act as a
matrix polymer in solid dispersion of drugs and also solubilize
drugs in aqueous media. Soluplus is a polyvinyl
caprolactam-polyvinyl acetate-polyethylene glycol copolymer (MW
around 118,000 g/mol), having a PEG backbone with one or two sides
chains consisting of vinyl acetate copolymerized with vinyl
caprolactam.
[0146] In this document, both HPMCAS and Soluplus were used as
references to evaluate the performance of OHPP in solubilizing
poorly water-soluble APIs in aqueous systems.
[0147] To evaluate the solubility of niclosamide in aqueous system,
10 mg of each complex or 2.5 mg niclosamide alone was mixed with
1.0 mL Hank's Balanced Salt Solution (HBSS) under constant
agitation for 2 h in a shaking water bath (37.degree. C., 100 rpm).
Thereafter, the dispersions were centrifuged at 16,000 g for 10
min, and the supernatants were collected for niclosamide
quantification using HPLC. The concentration of niclosamide in the
supernatant was considered as its water solubility.
[0148] The water solubility of niclosamide for niclosamide alone,
Nic-OHPP, Nic-HPMCAS, and Nic-Soluplus are compared in FIG. 2. The
solubility of niclosamide was around 2,178 .mu.L/mL with Nic-OHPP,
much greater than that of niclosamide alone (around 13.2 .mu.L/mL),
Nic-HPMCAS (around 35.4 .mu.L/mL), and Nic-Soluplus (around 353.8
.mu.L/mL).
Example 6-3: Solubility of Paclitaxel, with API/Excipient Ratio of
1/3
[0149] One part of paclitaxel was physically incorporated with 3
parts of OHPP, and the final product was in solid form. The
combined material between paclitaxel and OHPP is termed as
"paclitaxel-OHPP complex", "Pac-OHPP complex", or "Pac-OHPP" in
this document. Similarly the physically combined material between
paclitaxel and HPMCAS is termed as "paclitaxel-HPMCAS complex",
"Pac-HPMCAS complex", or "Pac-HPMCAS"; the physically combined
material between paclitaxel and Soluplus is termed as
"paclitaxel-Soluplus complex", "Pac-Soluplus complex", or
"Pac-Soluplus".
[0150] To evaluate the solubility of paclitaxel in aqueous system,
10 mg of each complex or 2.5 mg paclitaxel alone was mixed with 1.0
mL Hank's Balanced Salt Solution (HBSS) under constant agitation
for 2 h in a shaking water bath (37.degree. C., 100 rpm).
Thereafter, the dispersions were centrifuged at 16,000 g for 10
min, and the supernatants were collected for paclitaxel
quantification using HPLC. The concentration of paclitaxel in the
supernatant was considered as its water solubility.
[0151] The water solubility of paclitaxel for paclitaxel alone,
Pac-OHPP, Pac-HPMCAS, and Pac-Soluplus are compared in FIG. 3. The
solubility of paclitaxel was around 2,469 .mu.L/mL with Pac-OHPP,
much greater than that of paclitaxel alone (around 6.2 .mu.L/mL),
Pac-HPMCAS (around 135.6 .mu.L/mL), and Pac-Soluplus (around 20.8
.mu.L/mL).
Example 6-4: Solubility of Griseofulvin, with API/Excipient Ratio
of 1/3
[0152] One part of griseofulvin was physically incorporated with 3
parts of OHPP, and the final product was in solid form. The
combined material between griseofulvin and OHPP is termed as
"griseofulvin-OHPP complex", "Gri-OHPP complex", or "Gri-OHPP" in
this document. Similarly the physically combined material between
griseofulvin and HPMCAS is termed as "griseofulvin-HPMCAS complex",
"Gri-HPMCAS complex", or "Gri-HPMCAS"; the physically combined
material between griseofulvin and Soluplus is termed as
"griseofulvin-Soluplus complex", "Gri-Soluplus complex", or
"Gri-Soluplus".
[0153] To evaluate the solubility of griseofulvin in aqueous
system, 10 mg of each complex or 2.5 mg griseofulvin alone was
mixed with 1.0 mL Hank's Balanced Salt Solution (HBSS) under
constant agitation for 2 h in a shaking water bath (37.degree. C.,
100 rpm). Thereafter, the dispersions were centrifuged at 16,000 g
for 10 min, and the supernatants were collected for griseofulvin
quantification using HPLC. The concentration of griseofulvin in the
supernatant was considered as its water solubility.
[0154] The water solubility of griseofulvin for griseofulvin alone,
Gri-OHPP, Gri-HPMCAS, and Gri-Soluplus are compared in FIG. 4. The
solubility of griseofulvin was around 784.7 .mu.L/mL with Gri-OHPP,
much greater than that of griseofulvin alone (around 17.5
.mu.L/mL), Gri-HPMCAS (around 124.4 .mu.L/mL), and Gri-Soluplus
(around 68.2 .mu.L/mL).
Example 6-5: Solubility of Docetaxel, with APT/Excipient Ratio of
1/3
[0155] One part of docetaxel was physically incorporated with 3
parts of OHPP, and the final product was in solid form. The
combined material between docctaxel and OHPP is termed as
"docetaxel-OHPP complex", "Doc-OHPP complex", or "Doc-OHPP" in this
document. Similarly the physically combined material between
docetaxel and HPMCAS is termed as "docetaxel-HPMCAS complex",
"Doc-HPMCAS complex", or "Doc-HPMCAS"; the physically combined
material between docetaxel and Soluplus is termed as
"docetaxel-Soluplus complex", "Doc-Soluplus complex", or
"Doc-Soluplus".
[0156] To evaluate the solubility of docetaxel in aqueous system,
10 mg of each complex or 2.5 mg docetaxel alone was mixed with 1.0
mL Hank's Balanced Salt Solution (HBSS) under constant vortex for
10 min at 20.degree. C. Thereafter, the dispersions were
centrifuged at 16,000 g for 10 min, and the supernatants were
collected for docetaxel quantification using HPLC. The
concentration of docetaxel in the supernatant was considered as its
water solubility.
[0157] The water solubility of docetaxel for docetaxel alone,
Doc-OHPP, Doc-HPMCAS, and Doc-Soluplus are compared in FIG. 5. The
solubility of docetaxel was around 2,347 .mu.L/mL with Doc-OHPP,
much greater than that of docetaxel alone (around 11.1 .mu.L/mL),
Doc-HPMCAS (around 215.9 .mu.L/mL), and Doc-Soluplus (around 55.7
.mu.L/mL).
Example 6-6: Solubility of Itraconazole, with API/Excipient Ratio
of 1/3
[0158] One part of itraconazole was physically incorporated with 3
parts of OHPP, and the final product was in solid form. The
combined material between itraconazole and OHPP is termed as
"itraconazole-OHPP complex", "Itr-OHPP complex", or "Itr-OHPP" in
this document. Similarly the physically combined material between
itraconazole and HPMCAS is termed as "itraconazole-HPMCAS complex",
"Itr-HPMCAS complex", or "Itr-HPMCAS"; the physically combined
material between itraconazole and Soluplus is termed as
"itraconazole-Soluplus complex", "Itr-Soluplus complex", or
"Itr-Soluplus".
[0159] To evaluate the solubility of itraconazole in aqueous
system, 10 mg of each complex or 2.5 mg itraconazole alone was
mixed with 1.0 mL Hank's Balanced Salt Solution (HBSS) under
constant vortex for 10 min at 20.degree. C. Thereafter, the
dispersions were centrifuged at 16,000 g for 10 min, and the
supernatants were collected for itraconazole quantification using
HPLC. The concentration of itraconazole in the supernatant was
considered as its water solubility.
[0160] The water solubility of itraconazole for itraconazole alone,
Itr-OHPP, Itr-HPMCAS, and Itr-Soluplus are compared in FIG. 6. The
solubility of itraconazole was around 1,439.9 .mu.L/mL with
Itr-OHPP, much greater than that of itraconazole alone (around 0.96
.mu.L/mL), Itr-HPMCAS (around 4.6 .mu.L/mL), and Itr-Soluplus
(around 35.7 .mu.L/mL).
Example 6-7: Solubility of Curcumin, with API/Excipient Ratio of
1/9
[0161] One part of curcumin was physically incorporated with 9
parts of OHPP, and the final product was in solid form. The
combined material between curcumin and OHPP is termed as
"curcumin-OHPP complex", "Cur-OHPP complex", or "Cur-OHPP" in this
document. Similarly the physically combined material between
curcumin and HPMCAS is termed as "curcumin-HPMCAS complex",
"Cur-HPMCAS complex", or "Cur-HPMCAS"; the physically combined
material between curcumin and Soluplus is termed as
"curcumin-Soluplus complex", "Cur-Soluplus complex", or
"Cur-Soluplus".
[0162] To evaluate the solubility of curcumin in aqueous system, 10
mg of each complex or 1.0 mg curcumin alone was mixed with 1.0 mL
Hank's Balanced Salt Solution (HBSS) under constant agitation for 2
h in a shaking water bath (37.degree. C., 100 rpm). Thereafter, the
dispersions were centrifuged at 16,000 g for 10 min, and the
supernatants were collected for curcumin quantification using HPLC.
The concentration of curcumin in the supernatant was considered as
its water solubility.
[0163] The water solubility of curcumin for curcumin alone,
Cur-OHPP, Cur-HPMCAS, and Cur-Soluplus are compared in FIG. 7. The
solubility of curcumin was around 862.5 .mu.L/mL with Cur-OHPP,
much greater than that of curcumin alone (around 7.2 .mu.L/mL),
Cur-HPMCAS (around 5.0 .mu.L/mL), and Cur-Soluplus (around 85.4
.mu.L/mL).
Example 6-8: Solubility of Celecoxib, with API/Excipient Ratio of
1/5
[0164] One part of celecoxib was physically incorporated with 3
parts of OHPP and 2 parts of HPMCAS, and the final product was in
solid form. The combined material among celecoxib and OHPP and
HPMCAS is termed as "celecoxib-OHPP-HPMCAS complex",
"Cel-OHPP-HPMCAS complex", or "Cel-OHPP-HPMCAS" in this document.
Similarly the physically combined material between celecoxib and
HPMCAS is termed as "celecoxib-HPMCAS complex", "Cel-HPMCAS
complex", or "Cel-HPMCAS"; the physically combined material between
celecoxib and Soluplus is termed as "celecoxib-Soluplus complex",
"Cel-Soluplus complex", or "Cel-Soluplus".
[0165] To evaluate the solubility of celecoxib in aqueous system, 6
mg of each complex or 1.0 mg celecoxib alone was mixed with 1.0 mL
Hank's Balanced Salt Solution (HBSS) under constant agitation for 2
h in a shaking water bath (37.degree. C., 100 rpm). Thereafter, the
dispersions were centrifuged at 16,000 g for 10 min, and the
supernatants were collected for celecoxib quantification using
HPLC. The concentration of celecoxib in the supernatant was
considered as its water solubility.
[0166] The water solubility of celecoxib for celecoxib alone,
Cel-OHPP-HPMCAS, Cel-HPMCAS, and Cel-Soluplus are compared in FIG.
8. The solubility of celecoxib was around 772.3 .mu.L/mL with
Cel-OHPP-HPMCAS, much greater than that of celecoxib alone (around
12.8 .mu.L/mL), Cel-HPMCAS (around 62.9 .mu.L/mL), and Cel-Soluplus
(around 40.3 .mu.L/mL).
Example 7: Degree of Substitution (DS) of OHPP
[0167] DS of OHHP Determined Using .sup.1H NMR
[0168] OHPP was hydrolyzed sequentially in alkaline and acidic
conditions. First, 0.5 g OHPP and 0.1 g NaOH were dissolved in 5 mL
deionized H.sub.2O and heated in a boiling-water bath for 1 h.
Thereafter, 0.25 mL 5M H.sub.2SO.sub.4 were added to the OHPP
dispersion to neutralize the fluid. For acidic hydrolyzation, 5M
H.sub.2SO.sub.4 was added to the neutralized system to bring the
concentration of H.sup.+ to 1N, and the reactant was heated in a
boiling-water bath for 1 h. Thereafter, the system was neutralized
using 5M NaOH. The product solution was lyophilized to collect
hydrolyzed OHPP.
[0169] Twenty milligrams of hydrolyzed OHHP solid was dissolved in
1 mL deuterium oxide (D.sub.2O) and lyophilized again. The
D.sub.2O-exchanged OHHP was dissolved in 1 mL D.sub.2O for NMR
determination of DS for both hydroxypropyl group and
octenylsuccinate group with OHHP.
[0170] The .sup.1H NMR measurements were performed at 50.degree. C.
with a Bruker Avance DRX-500 NMR spectrometer operating at 499.89
MHz and equipped with a 5 mm inverse-detection triple-resonance
Z-gradient probe.
[0171] According to the .sup.1H NMR spectra (FIG. 9), the relative
molar amount of octenyl succinate calculated from the signal peak
area (around 1.1 ppm) of its methyl group (--CH.sub.3) was
0.33.
[0172] The relative molar amount of hydroxypropyl group was
obtained from the signal peak area of its methyl group. This was
calculated by subtracting the signal peak area related to some
methylene (--CH.sub.2--) units in the octenyl succinate group from
the signal peak area ranging 1.34-1.64 ppm. The relative molar
amount of hydroxypropyl group thus calculated was 1.8.
[0173] The relative molar amount of glucosyl unit of phytoglycogen
was obtained from the signal peak area associated with C2, C3, C4,
C5, and C6 of glucosyl units. This was calculated by subtracting
the signal peak area of --O--CH.sub.2-- and --CH(CH.sub.3)--O-- of
the hydroxypropyl group from the signal peak area ranging 3.57-4.35
ppm. The relative molar amount of glucosyl unit thus calculated was
0.83.
[0174] Therefore, the DS of octenyl succinate group was
0.33/0.83=0.40, and the DS of hydroxypropyl group was
1.8/0.83=2.17.
Example 8: Caco-2 Monolayer Permeation of Niclosamide and
Celecoxib
[0175] Caco-2 cells were seeded in the inserts with
tissue-culture-treated polyester membranes (Transwells, 0.4 .mu.m
pore size, Corning) at a density of 1.times.10.sup.4 cells/well.
After seeding, the medium was changed every other day until the day
of the permeation test. All tests were performed on day 21 after
seeding. For the test, the culture medium was removed and the cells
were washed twice with PBS buffer. The cells were then equilibrated
in HBSS for 15 min prior to each study, and then apical and
basolateral solution were aspirated.
[0176] To measure the apical-to-basolateral permeation of API, 0.5
mL of each test solution was added to the apical compartment, and
the basolateral compartment received 1.5 mL HBSS. As a control,
reference cells were incubated with 0.5 mL blank HBSS on the apical
side, while the basolateral side received 1.5 mL of HBSS. All
cultures were incubated in an incubator (5% CO.sub.2, 37.degree.
C.) for 2 h. After the incubation, the apical and the basolateral
solutions were collected respectively and their amounts of API were
determined using HPLC.
[0177] The loaded dispersions were prepared in two steps: (1)
dispersing API-excipient complex solid and API alone in HBSS at the
doses of 1000 .mu.g/mL or 100 .mu.g/mL, and (2) subjecting each
dispersion to centrifugation (16,000 g, 5 min) to collect
supernatant. The supernatants were loaded in the apical
compartments of inserts.
[0178] FIG. 10 shows the impact of improved API solubility on its
permeation through epithelial membranes, using Caco-2 monolayer as
the model. For niclosamide alone and celecoxib alone, the soluble
portion of API in the simulated intestinal buffer (HBSS) was not
sufficient to provide an appreciable permeation, even at a very
high initial dose (1,000 .mu.g/mL). When OHPP was used, the
permeation was substantially increased even at a low initial
concentration (100 .mu.g/mL). Evidently, OHPP greatly enhanced the
permeation of API molecules.
Example 9: In Vitro Anticancer Efficacies of Niclosamide and
Paclitaxel Enhanced by OHPP
[0179] Paclitaxel is an anticancer drug with activity against a
wide variety of human malignancies, such as ovarian, breast and
lung, bladder, prostate, melanoma and esophageal cancer. However,
its poor water-solubility limits its effective application.
Commercially, paclitaxel is solubilized in cremophor EL and ethanol
for intravenous administration, which may cause allergic reactions
and precipitation on aqueous dilution. Recently, paclitaxel has
been used in the clinical trials for gastric cancers and other
advanced solid cancer via oral administration.
[0180] Niclosamide is an anthelmintic drug used for the treatment
of worm infestations in humans and animals. Importantly, recent
studies have shown that niclosamide is a promising anticancer agent
against various human cancers, such as leukemia, ovarian and breast
carcinoma, which results from its ability in interfering with
multiple cell signaling/regulatory pathways, such as NF-.kappa.B,
ROS, Notch, Wnt/b-catenin and mTORc1. These properties assure
niclosamide less tendency to cause resistance from cancer cells. As
a highly permeable drug, however, niclosamide's low water
solubility greatly reduces its efficacy.
[0181] For the oral administration of poorly water-soluble
anticancer APIs such as paclitaxel, niclosamide, and docetaxel,
sufficient water solubility is essential to their high local
bioaccessibility to cancer cells in the gastrointestinal tract and
to their bioavailability for reaching cancer cells at locations
other than the GI tract. While OHPP is able to dissolve paclitaxel
and niclosamide, we wanted to confirm that the dissolved APIs were
accessible to cancer cells and show cytotoxicity. To evaluate the
performance of OHPP to solubilize and release APIs, we tested the
cytotoxicity of paclitaxel and niclosamide complexed with OHPP.
[0182] In drug screening and in vitro efficacy studies, dimethyl
sulfoxide (DMSO) has been used to dissolve poorly water-soluble
APIs. While DMSO cannot be used in actual drug formulations, the
DMSO-dissolved API can be used as a benchmark to evaluate the
efficacies of APIs dissolved by OHPP and other commercial
solubilizers, such as HPMCAS and Soluplus. As shown in FIG. 11, the
efficacies of excipient-dispersed paclitaxel and niclosamide were
tested against HeLa (a cervical cancer cell line,
ATCC.RTM.CCL-2.TM.) and PC-3 (a prostate cancer cell,
ATCC.RTM.CRL-1435.TM.) respectively.
[0183] The in vitro anticancer testing results were highly
encouraging. As shown in FIG. 11A, OHPP-dispersed paclitaxel
(Pac-OHPP) demonstrated at least an equivalent, if not higher
anti-HeLa efficacy as compared with DMOS-dissolved preparation
(Pac-DMSO). In particular, the cytotoxicity of Pac-OHPP was
significantly higher than that of Pac-DMSO at concentrations below
1.0 .mu.g/mL. Based on the plot of cell viability vs. dose,
IC.sub.50 was approximately 0.095 .mu.g/mL for Pac-OHPP, and 0.19
.mu.g/mL for Pac-DMSO. In comparison, IC.sub.50 for Pac-HPMCAS and
Pac-Soluplus were 1.74 and 9.8 .mu.g/mL, respectively.
[0184] For niclosamide against PC-3 cell, as shown in FIG. 11B,
OHPP-dispersed niclosamide (Nic-OHPP) demonstrated a similar
anti-tumoral efficacy as compared with DMSO-dissolved preparation
(Nic-DMSO). Based on the plot of cell viability vs. dose, IC.sub.50
was approximately 0.18 .mu.g/mL for Nic-OHPP, and 0.15 .mu.g/mL for
Nic-DMSO. In comparison, the IC.sub.50 for Pac-HPMCAS and
Pac-Soluplus were 2.1 and 2.3 .mu.g/mL, respectively.
[0185] It should be noted that, the X-axis and the IC.sub.50
results for Pac (Nic)-DMSO, Pac (Nic)-OHPP, Pac (Nic)-HPMCAS, and
Pac (Nic)-Soluplus were all "apparent dose", i.e. those calculated
based on the total API amount in the initial stock dispersion and
dilution factors. For Pac (Nic)-HPMCAS and Pac (Nic)-Soluplus, the
majority of API added in buffer was not soluble in the initial
preparations. Therefore, the actual amount of paclitaxel
(niclosamide) in the soluble portion (that was sequentially diluted
for cytotoxicity testing) was much lower than that for Pac
(Nic)-DMSO and Pac (Nic)-OHPP. This procedure of diluting the
dissolved portion of API stock simulates the scenario in which the
therapeutic outcome of a dosage form is governed by the dissolved
API portion that may reach the target sites.
[0186] The complete disclosure of all patents, patent applications,
and publications, and electronically available materials cited
herein are incorporated by reference. The foregoing detailed
description and examples have been given for clarity of
understanding only. No unnecessary limitations are to be understood
therefrom. The invention is not limited to the exact details shown
and described, for variations obvious to one skilled in the art
will be included within the invention defined by the claims.
* * * * *