U.S. patent application number 17/399015 was filed with the patent office on 2022-06-30 for antifungal agents used in combination.
The applicant listed for this patent is Scynexis, Inc.. Invention is credited to David A. Angulo Gonzalez.
Application Number | 20220202833 17/399015 |
Document ID | / |
Family ID | |
Filed Date | 2022-06-30 |
United States Patent
Application |
20220202833 |
Kind Code |
A1 |
Angulo Gonzalez; David A. |
June 30, 2022 |
ANTIFUNGAL AGENTS USED IN COMBINATION
Abstract
The present invention relates to the use of enfumafungin
derivative triterpenoid antifungal compounds in combination with
other antifungal agents such azoles, polyenes, lipopeptides, and
allylamides to treat fungal diseases. More particularly, the
invention relates to antifungal combinations of enfumafungin
derivative triterpenoids which are inhibitors of
(1,3)-.beta.-D-glucan synthesis, in combination with other
antifungal agents such as mold-active agents that have activity
against molds, including but not limited to voriconazole,
isavuconazole, posaconazole, itraconazole and amphotericin B, for
the treatment and/or prevention of infections caused by molds.
Inventors: |
Angulo Gonzalez; David A.;
(Palmetto Bay, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Scynexis, Inc. |
Jersey City |
NJ |
US |
|
|
Appl. No.: |
17/399015 |
Filed: |
August 10, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15945428 |
Apr 4, 2018 |
11110102 |
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17399015 |
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62483647 |
Apr 10, 2017 |
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International
Class: |
A61K 31/58 20060101
A61K031/58; A61K 31/4439 20060101 A61K031/4439; A61P 31/10 20060101
A61P031/10; A61K 31/4196 20060101 A61K031/4196; A61K 45/06 20060101
A61K045/06; A61K 31/496 20060101 A61K031/496; A61K 31/506 20060101
A61K031/506; A61K 31/7048 20060101 A61K031/7048 |
Claims
1. A pharmaceutical combination of: (a) a first therapeutic agent
that is a compound of Formula (I): ##STR00007## or a
pharmaceutically acceptable salt thereof, wherein: X is O or H, H;
R.sup.e is C(O)NR.sup.fR.sup.g or a 6-membered ring heteroaryl
group containing 1 or 2 nitrogen atoms wherein the heteroaryl group
is optionally mono-substituted on a ring carbon with fluoro or
chloro or on a ring nitrogen with oxygen; R.sup.f, R.sup.g, R.sup.6
and R.sup.7 are each independently hydrogen or C.sub.1-C.sub.3
alkyl; R.sup.8 is C.sub.1-C.sub.4 alkyl, C.sub.3-C.sub.4 cycloalkyl
or C.sub.4-C.sub.5 cycloalkyl-alkyl; R.sup.9 is methyl or ethyl;
and R.sup.8 and R.sup.9 are optionally taken together to form a
6-membered saturated ring containing 1 oxygen atom; and (b) a
second therapeutic agent that is an azole, a polyene, a purine or
pyrimidine nucleotide inhibitor, an orotomide, a Gwt1 inhibitor, a
pneumocandin or echinocandin derivative, a protein elongation
factor inhibitor, a chitin inhibitor, a mannan inhibitor, a
bactericidal/permeability-inducing (BPI) protein product, or an
immunomodulating agent.
2. The pharmaceutical combination according to claim 1, wherein the
second therapeutic agent is itraconazole, ketoconazole, miconazole,
fluconazole, voriconazole, posaconazole, amphotericin B,
flucytosine, anidulafungin, micafungin, or caspofungin.
3. The pharmaceutical combination according to claim 1, wherein the
first therapeutic agent is a compound of Formula (II): ##STR00008##
which is
(1S,4aR,6aS,7R,8R,10aR,10bR,12aR,14R,15R)-15-[[2-amino-2,3,3-trimethylbut-
yl]oxy]-8-[(1R)-1,2-dimethylpropyl]-14-[5-(4-pyridinyl)-1H-1,2,4-triazol-1-
-yl]-1,6,6a,7,8,9,10,10a,10b,11,12,12a-dodecahydro-1,6a,8,10a-tetramethyl--
4H-1,4a-propano-2H-phenanthro[1,2-c]pyran-7-carboxylic acid, or a
pharmaceutically acceptable salt thereof; and the second
therapeutic agent is voriconazole, isavuconazole, posaconazole,
itraconazole, or amphotericin B.
4. The pharmaceutical combination according to claim 1, wherein the
first therapeutic agent is a compound of Formula (IIa):
##STR00009## which is
(1S,4aR,6aS,7R,8R,10aR,10bR,12aR,14R,15R)-15-[[(2R)-2-amino-2,3,3-trimeth-
ylbutyl]oxy]-8-[(1R)-1,2-dimethylpropyl]-14-[5-(4-pyridinyl)-1H-1,2,4-tria-
zol-1-yl]-1,6,6a,7,8,9,10,10a,10b,11,12,12a-dodecahydro-1,6a,8,10a-tetrame-
thyl-4H-1,4a-propano-2H-phenanthro[1,2-c]pyran-7-carboxylic acid,
or a pharmaceutically acceptable salt thereof; and the second
therapeutic agent is voriconazole, isavuconazole, posaconazole,
itraconazole, or amphotericin B.
5. The pharmaceutical combination according to claim 3, wherein the
second therapeutic agent is voriconazole.
6. The pharmaceutical combination according to claim 4, wherein the
second therapeutic agent is voriconazole.
7. The pharmaceutical combination according to claim 3, wherein the
second therapeutic agent is isavuconazole.
8. The pharmaceutical combination according to claim 4, wherein the
second therapeutic agent is isavuconazole.
9. The pharmaceutical combination according to claim 3, wherein the
second therapeutic agent is amphotericin B.
10. The pharmaceutical combination according to claim 4, wherein
the second therapeutic agent is amphotericin B.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the use of enfumafungin
derivative triterpenoid antifungal compounds in combination with
other antifungal agents such azoles, polyenes, lipopeptides, and
allylamides to treat fungal diseases. More particularly, the
invention relates to antifungal combinations of enfumafungin
derivative triterpenoids (or pharmaceutically acceptable salts
thereof) which are inhibitors of (1,3)-.beta.-D-glucan synthesis,
in combination with other antifungal agents such as mold-active
agents that have activity against molds, including but not limited
to voriconazole, isavuconazole, posaconazole, itraconazole, and
amphotericin B, for the treatment and/or prevention of infections
caused by molds.
BACKGROUND OF THE INVENTION
[0002] Fungal infections caused by molds are a major healthcare
problem with high associated mortality. Several molds, including
Aspergillus species, Zygomycetes, Fusarium species, and
Scedosporium species, can cause systemic fungal infections. Among
these, Aspergillus spp. is the most common, accounting for
approximately 85% of cases. Invasive pulmonary aspergillosis is a
life-threatening infection for immunocompromised patients, with
high mortality rates (20-40% range) despite the availability of
antifungal agents with activity against the causative pathogen
(Aspergillus spp.). The first recommended treatment option for
invasive aspergillosis is mold-active azole antifungals (e.g.,
voriconazole, isavuconazole, posaconazole, and itraconazole).
Amphotericin B formulations are a secondary option due to
significant renal toxicity. Despite the availability of mold-active
antifungals, treatment outcomes are not optimal, leading to
frequent treatment failures and mortality.
[0003] In addition, there has been an emergence of azole-resistant
Aspergillus species, further limiting therapeutic options for
patients. Different and more effective treatment approaches are
needed, and combination therapy may play an important role.
Combination therapy, to be effective, should include antifungal
agents that when administered together show a synergistic
interaction that can potentially increase antifungal efficacy,
reduce toxicity, cure faster, prevent or avoid the emergence of
resistance, and/or provide broader-spectrum antifungal activity in
comparison with monotherapy regimens. However, combination therapy
may also be deleterious in the case of antagonistic interactions,
decrease in antifungal efficacy, and increase in toxicity.
[0004] Enfumafungin is a hemiacetal triterpene glycoside that is
produced in fermentations of a Hormonema spp. associated with
living leaves of Juniperus communis (U.S. Pat. No. 5,756,472;
Pelaez et al., Systematic and Applied Microbiology, 23:333-343,
2000; Schwartz et al., JACS, 122:4882-4886, 2000; Schwartz, R. E.,
Expert Opinion on Therapeutic Patents, 11(11):1761-1772, 2001).
Enfumafungin is one of the several triterpene glycosides that have
in vitro antifungal activities. The mode of the antifungal action
of enfumafungin and other antifungal triterpenoid glycosides was
determined to be the inhibition of fungal cell wall glucan
synthesis by their specific action on (1,3)-.beta.-D-glucan
synthase (Onishi et al., Antimicrobial Agents and Chemotherapy,
44:368-377, 2000; Pelaez et al., Systematic and Applied
Microbiology, 23:333-343, 2000). (1,3)-.beta.-D-glucan synthase
remains an attractive target for antifungal drug action because it
is present in many pathogenic fungi and thereby affords broad
antifungal spectrum; in addition, there is no mammalian
counterpart, and consequently, these compounds have little or no
mechanism-based toxicity. The triterpenoid compound derivatives of
enfumafungin related to this invention have demonstrated activity
against fungal isolates that are resistant to other glucan synthase
inhibitors (e.g., lipopeptide agents such as echinocandins)
indicating that the biological and molecular target of the
enfumafungin derivatives is different from that of other glucan
synthase inhibitors.
[0005] Various enfumafungin derivatives have been disclosed, e.g.,
in International Patent Publication Nos. WO 2007/126900 and WO
2007/127012.
[0006] Previous studies have evaluated the efficacy of other
antifungal agents in combination for the treatment of Aspergillus
spp. infections but have failed to conclusively demonstrate
improved outcomes (Marr K, et al., Ann Intern Med. 2015;
162:81-89). These sub-optimal outcomes with combination therapy of
available antifungals may be related to the lack of availability of
oral formulations (e.g., for echinocandins and amphotericin B)
limiting their long-term use (long-term use often being needed for
the treatment of mold infections), and the emergence of resistance,
particularly to azoles (the only agents available for oral and IV
administration for Aspergillus infections). Other limitations of
currently available antifungals for the treatment of mold
infections include the high risk of drug-to-drug interactions of
the azoles, and the renal toxicity associated with amphotericin B.
There is a need in the art for antifungal combinations that provide
improved cure and survival outcomes for fungal infections and that
are suitable for long-term combination therapy, as needed for the
treatment of mold infections. There is also a need in the art for
safe and effective antifungal agents to be used in combination that
may allow a reduction in the use of amphotericin B and azoles
(e.g., by reduction of daily dosage or reduction of treatment
duration), minimizing the risk of associated toxicities.
SUMMARY OF THE INVENTION
[0007] The present invention relates to enfumafungin derivatives
used in combination with other mold-active antifungal agents for
the treatment and/or prevention of mold infections. Enfumafungin
derivatives, and pharmaceutically acceptable salts thereof, are
useful in the inhibition of (1,3)-.beta.-D-glucan synthase, and are
useful in combination with other mold-active agents in the
prevention or treatment of mycotic infections caused by one or more
of various pathogens including but not limited to Aspergillus,
Mucor, Fusarium, and Scedosporium species. The present invention
addresses needs in the art such as those described above at least
because the enfumafungin derivatives are active against
azole-resistant Aspergillus strains, can be administered both
intravenously and orally, and have very low risk for drug-to-drug
interactions, and their use in the combinations described herein
overcomes the limitations of other antifungal compounds and
combinations.
[0008] The present invention provides combinations of
[0009] (a) a compound of Formula (I), or a pharmaceutically
acceptable salt thereof:
##STR00001## [0010] wherein: [0011] X is O or H, H; [0012] R.sup.e
is C(O)NR.sup.fR.sup.g or a 6-membered ring heteroaryl group
containing 1 or 2 nitrogen atoms wherein the heteroaryl group is
optionally mono-substituted on a ring carbon with fluoro or chloro
or on a ring nitrogen with oxygen; [0013] R.sup.f, R.sup.g, R.sup.6
and R.sup.7 are each independently hydrogen or C.sub.1-C.sub.3
alkyl; [0014] R.sup.8 is C.sub.1-C.sub.4 alkyl, C.sub.3-C.sub.4
cycloalkyl or C.sub.4-C.sub.5 cycloalkyl-alkyl; [0015] R.sup.9 is
methyl or ethyl; and [0016] R.sup.8 and R.sup.9 are optionally
taken together to form a 6-membered saturated ring containing 1
oxygen atom; and
[0017] (b) a second antifungal agent, such as a mold-active agent
having activity against molds, such as an antifungal azole compound
or a polyene such as amphotericin B.
[0018] The invention also provides methods of treating or
preventing fungal infection in patients using the compound of
Formula (I) in combination with the second antifungal agent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a graph showing cumulative survival probability
from a study of New Zealand White rabbits inoculated with
Aspergillus fumigatus isolate that were not treated with an
antifungal agent (control), or were then treated with SCY-078
alone, with isavuconazole alone, or with a combination of SCY-078
and isavuconazole.
[0020] FIG. 2 is a graph showing pulmonary infarct scores from the
study referenced in FIG. 1.
[0021] FIG. 3 is a graph showing galactomannan antigen levels
detected in serum from the rabbits from the study referenced in
FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The present invention provides combinations of
[0023] (a) a compound of Formula (I), or a pharmaceutically
acceptable salt thereof:
##STR00002## [0024] wherein: [0025] X is O or H, H; [0026] R.sup.e
is C(O)NR.sup.fR.sup.g or a 6-membered ring heteroaryl group
containing 1 or 2 nitrogen atoms wherein the heteroaryl group is
optionally mono-substituted on a ring carbon with fluoro or chloro
or on a ring nitrogen with oxygen; [0027] R.sup.f, R.sup.g, R.sup.6
and R.sup.7 are each independently hydrogen or C.sub.1-C.sub.3
alkyl; [0028] R.sup.8 is C.sub.1-C.sub.4 alkyl, C.sub.3-C.sub.4
cycloalkyl or C.sub.4-C.sub.5 cycloalkyl-alkyl; [0029] R.sup.9 is
methyl or ethyl; and [0030] R.sup.8 and R.sup.9 are optionally
taken together to form a 6-membered saturated ring containing 1
oxygen atom; and
[0031] (b) a second antifungal agent, such as a mold-active agent
having activity against molds, such as an antifungal azole compound
or a polyene such as amphotericin B.
[0032] The present invention also provides combinations of
[0033] (a) a compound of Formula (Ia), or a pharmaceutically
acceptable salt thereof:
##STR00003## [0034] wherein the substituents are as provided for in
Formula (I); and
[0035] (b) a second antifungal agent, such as a mold-active agent
having activity against molds, such as an antifungal azole compound
or a polyene such as amphotericin B.
[0036] In embodiment 1: X is H, H, and the other substituents are
as provided for in Formula (I).
[0037] In embodiment 2: R.sup.e is either pyridyl or pyrimidinyl
optionally mono-substituted on a ring carbon with fluoro or chloro
or on a ring nitrogen with oxygen, and the other substituents are
as provided in embodiment 1 or in Formula (I).
[0038] In embodiment 3: R.sup.e is 4-pyridyl and the other
substituents are as provided in embodiment 1 or in Formula (I).
[0039] In embodiment 4: R.sup.e is C(O)NH.sub.2 or
C(O)NH(C.sub.1-C.sub.3 alkyl) and the other substituents are as
provided in embodiment 1 or in Formula (I).
[0040] In embodiment 5: R.sup.8 is C.sub.1-C.sub.4 alkyl and
R.sup.9 is methyl; and the other substituents are as provided in
embodiment 1, 2, 3, or 4, or in Formula (I).
[0041] In embodiment 6: R.sup.8 is t-butyl, R.sup.9 is methyl; and
the other substituents are as provided in embodiment 1, 2, 3, or 4,
or in Formula (I).
[0042] In embodiment 7: R.sup.6 and R.sup.7 are each independently
hydrogen or methyl and the other substituents are as provided in
embodiment 1, 2, 3, 4, 5, or 6, or in Formula (I).
[0043] In embodiment 1': X is H, H, and the other substituents are
as provided for in Formula (Ia).
[0044] In embodiment 2': R.sup.e is either pyridyl or pyrimidinyl
optionally mono-substituted on a ring carbon with fluoro or chloro
or on a ring nitrogen with oxygen, and the other substituents are
as provided in embodiment 1' or in Formula (Ia).
[0045] In embodiment 3': R.sup.e is 4-pyridyl and the other
substituents are as provided in embodiment 1' or in Formula
(Ia).
[0046] In embodiment 4': R.sup.e is C(O)NH.sub.2 or
C(O)NH(C.sub.1-C.sub.3 alkyl) and the other substituents are as
provided in embodiment 1' or in Formula (Ia).
[0047] In embodiment 5': R.sup.8 is C.sub.1-C.sub.4 alkyl and
R.sup.9 is methyl; and the other substituents are as provided in
embodiment 1', 2', 3', or 4', or in Formula (Ia).
[0048] In embodiment 6': R.sup.8 is t-butyl, R.sup.9 is methyl; and
the other substituents are as provided in embodiment 1', 2', 3', or
4', or in Formula (Ia).
[0049] In embodiment 7': R.sup.6 and R.sup.7 are each independently
hydrogen or methyl and the other substituents are as provided in
embodiment 1', 2', 3', 4', 5', or 6', or in Formula (Ia).
[0050] In preferred embodiments, the present invention provides a
combination of
[0051] (a) a compound of Formula (II):
##STR00004##
which is
(1S,4aR,6aS,7R,8R,10aR,10bR,12aR,14R,1SR)-15-[[2-amino-2,3,3-tri-
methylbutyl]oxy]-8-[(1R)-1,2-dimethylpropyl]-14-[5-(4-pyridinyl)-JH-1,2,4--
triazol-1-yl]-1,6,6a,7,8,9,10,10a,10b,11,12,12a-dodecahydro-1,6a,8,10a-tet-
ramethyl-4H-1,4a-propano-2H-phenanthro[1,2-c]pyran-7-carboxylic
acid, [0052] or a pharmaceutically acceptable salt thereof; and
[0053] (b) a second antifungal agent selected from voriconazole,
isavuconazole, posaconazole, itraconazole, and amphotericin B.
[0054] In other preferred embodiments, the present invention
provides a combination of
[0055] (a) a compound of formula (IIa) (herein referred to as
SCY-078):
##STR00005##
which is
(1S,4aR,6aS,7R,8R,10aR,10bR,12aR,14R,15R)-15-[[(2R)-2-amino-2,3,-
3-trimethylbutyl]oxy]-8-[(1R)-1,2-dimethylpropyl]-14-[5-(4-pyridinyl)-1H-1-
,2,4-triazol-1-yl]-1,6,6a,7,8,9,10,10a,10b,11,12,12a-dodecahydro-1,6a,8,10-
a-tetramethyl-4H-1,4a-propano-2H-phenanthro[1,2-c]pyran-7-carboxylic
acid, [0056] or a pharmaceutically acceptable salt thereof; and
[0057] (b) a second antifungal agent selected from voriconazole,
isavuconazole, posaconazole, itraconazole, and amphotericin B.
[0058] In other preferred embodiments, the present invention
provides a combination of: the citrate salt of the compound of
formula (II), and a second antifungal agent selected from
voriconazole, isavuconazole, posaconazole, itraconazole and
amphotericin B.
[0059] In other preferred embodiments, the present invention
provides a combination of: the citrate salt of the compound of
formula (IIa), and a second antifungal agent selected from
voriconazole, isavuconazole, posaconazole, itraconazole, and
amphotericin B.
[0060] Other embodiments of the present invention include the
following:
[0061] (aa) A combination of: a composition comprising a compound
of Formula (I), (Ia), (II), or (IIa), or a pharmaceutically
acceptable salt thereof, and a carrier, adjuvant, or vehicle; and a
second therapeutic agent.
[0062] (bb) A combination of: a pharmaceutical composition
comprising a compound of Formula (I), (Ia), (II), or (IIa), or a
pharmaceutically acceptable salt thereof, and a pharmaceutically
acceptable carrier, adjuvant, or vehicle; and a second therapeutic
agent.
[0063] (cc) The combination of (bb), wherein the second therapeutic
agent is an azole, a polyene, a purine or pyrimidine nucleotide
inhibitor, an orotomide, a Gwt1 inhibitor, a pneumocandin or
echinocandin derivative, a protein elongation factor inhibitor, a
chitin inhibitor, a mannan inhibitor, a
bactericidal/permeability-inducing (BPI) protein product, or an
immunomodulating agent.
[0064] (dd) The combination of (cc), wherein the second therapeutic
agent is itraconazole, ketoconazole, miconazole, fluconazole,
voriconazole, posaconazole, amphotericin B, flucytosine,
anidulafungin, micafungin, or caspofungin.
[0065] (ee) A pharmaceutical combination that is: a compound of
Formula (I), (Ia), (II), or (IIa), or a pharmaceutically acceptable
salt thereof; and a second therapeutic agent; wherein the compound
(or the pharmaceutically acceptable salt thereof) and the second
therapeutic agent are employed in amounts that render the
combination effective for treating or preventing fungal and/or
bacterial infections.
[0066] (ff) The combination of (ee), wherein the second therapeutic
agent is an azole, a polyene, a purine or pyrimidine nucleotide
inhibitor, an orotomide, a Gwt1 inhibitor, a pneumocandin or
echinocandin derivative, a protein elongation factor inhibitor, a
chitin inhibitor, a mannan inhibitor, a
bactericidal/permeability-inducing (BPI) protein product, or an
immunomodulating agent.
[0067] (gg) The combination of (ff), wherein the second therapeutic
agent is itraconazole, ketoconazole, miconazole, fluconazole,
voriconazole, posaconazole, amphotericin B, flucytosine,
anidulafungin, micafungin, or caspofungin.
[0068] (hh) A method of treating or preventing a mycotic infection
in a subject in need thereof comprising administering to the
subject a combination of: a first therapeutic agent that is a
compound of Formula (I), (Ia), (II), or (IIa), or a
pharmaceutically acceptable salt thereof; and a second therapeutic
agent that is effective against a fungal and/or a bacterial
infection.
[0069] (ii) The method of (hh), wherein the second therapeutic
agent is an azole, a polyene, a purine or pyrimidine nucleotide
inhibitor, an orotomide, a Gwt1 inhibitor, a pneumocandin or
echinocandin derivative, a protein elongation factor inhibitor, a
chitin inhibitor, a mannan inhibitor, a
bactericidal/permeability-inducing (BPI) protein product, or an
immunomodulating agent.
[0070] (jj) The method of (hh), wherein the second therapeutic
agent is itraconazole, ketoconazole, miconazole, fluconazole,
voriconazole, posaconazole, amphotericin B, flucytosine,
anidulafungin, micafungin, or caspofungin.
[0071] (kk) The method of (hh), wherein the first therapeutic agent
is administered either sequentially or concurrently with the second
therapeutic agent.
[0072] (ll) The method of (hh), wherein the therapeutic agents are
administered intravenously, orally, and/or topically.
[0073] (mm) The method of (hh), wherein the mycotic infection is
caused by Aspergillosis spp.
[0074] (nn) A method of treating or preventing invasive pulmonary
aspergillosis in a subject in need thereof comprising administering
to the subject a combination of: a first therapeutic agent that is
a compound of Formula (I), (Ia), (II), or (IIa), or a
pharmaceutically acceptable salt thereof; and a second therapeutic
agent that is effective against a fungal and/or a bacterial
infection.
[0075] (oo) The method of (nn), wherein the second therapeutic
agent is an azole, a polyene, a purine or pyrimidine nucleotide
inhibitor, an orotomide, a Gwt1 inhibitor, a pneumocandin or
echinocandin derivative, a protein elongation factor inhibitor, a
chitin inhibitor, a mannan inhibitor, a
bactericidal/permeability-inducing (BPI) protein product, or an
immunomodulating agent.
[0076] (pp) The method of (nn), wherein the second therapeutic
agent is itraconazole, ketoconazole, miconazole, fluconazole,
voriconazole, isavuconazole, posaconazole, amphotericin B,
flucytosine, anidulafungin, micafungin, or caspofungin.
[0077] (qq) The method of (nn), wherein the first therapeutic agent
is administered either sequentially or concurrently with the second
therapeutic agent.
[0078] (rr) The method of (nn), wherein the therapeutic agents are
administered intravenously, orally, and/or topically.
[0079] (ss) A method of treating a fungal and/or mold infection in
a subject in need thereof, the method comprising administering to
the subject a therapeutically effective amount of: a compound of
Formula (I), (Ia), (II), or (IIa), or a pharmaceutically acceptable
salt thereof, and a carrier, adjuvant, or vehicle; and a second
antifungal agent, wherein the combination is synergistic.
[0080] The present invention also relates to methods of reducing
the levels of galactomannan--a component of the cell wall of
Aspergillus species--in a subject in need thereof, comprising
administering to the subject a combination of: a first therapeutic
agent that is a compound of Formula (I), (Ia), (II), or (IIa), or a
pharmaceutically acceptable salt thereof; and a second therapeutic
agent that is effective against a fungal and/or a bacterial
infection. In certain embodiments, the first therapeutic agent is a
compound of Formula (II) or a pharmaceutically acceptable salt
thereof; and the second therapeutic agent is voriconazole,
isavuconazole, posaconazole, itraconazole, or amphotericin B. In
further embodiments, the first therapeutic agent is a compound of
Formula (IIa) or a pharmaceutically acceptable salt thereof; and
the second therapeutic agent is voriconazole, isavuconazole,
posaconazole, itraconazole, or amphotericin B. Galactomannan levels
in a subject can be determined, for example, by measuring
galactomannan in serum or plasma from blood samples collected from
the subject, or by bronchoalveolar lavage.
[0081] The present invention also includes any of the foregoing
combinations: for use in, for use as a medicament for, or for use
in the preparation of a medicament for treating or preventing a
mycotic infection in a subject in need thereof; or for use in, for
use as a medicament for, or for use in the preparation of a
medicament for treating or preventing invasive pulmonary
aspergillosis in a subject in need thereof.
[0082] In the description of compounds in the embodiments set forth
above, indicated substitutions are included only to the extent that
the substituents provide stable compounds consistent with the
definition.
[0083] The compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof,
have antimicrobial (e.g., antifungal) activities against yeasts and
other fungi, including one or more of Acremonium, Absidia (e.g.,
Absidia corymbifera), Alternaria, Aspergillus (e.g., Aspergillus
clavatus, Aspergillus flavus, Aspergillus fumigatus, Aspergillus
nidulans, Aspergillus niger, Aspergillus terreus, and Aspergillus
versicolor), Bipolaris, Blastomyces (e.g., Blastomyces
dermatitidis), Blastoschizomyces (e.g., Blastoschizomyces
capitatus), Candida (e.g., Candida albicans, Candida glabrata
(Torulopsis glabrata), Candida guilliermondii, Candida kefyr,
Candida krusei, Candida lusitaniae, Candida parapsilosis, Candida
pseudotropicalis, Candida stellatoidea, Candida tropicalis, Candida
utilis, Candida lipolytica, Candida famata and Candida rugosa),
Cladosporium (e.g., Cladosporium carrionii and Cladosporium
trichloides), Coccidioides (e.g., Coccidioides immitis),
Cryptococcus (e.g., Cryptococcus neoformans), Curvularia,
Cunninghamella (e.g., Cunninghamella elegans), Dermatophyte,
Exophiala (e.g., Exophiala dermatitidis and Exophiala spinifera),
Epidermophyton (e.g., Epidermophyton floccosum), Fonsecaea (e.g.,
Fonsecaea pedrosoi), Fusarium (e.g., Fusarium solani), Geotrichum
(e.g., Geotrichum candidum and Geotrichum clavatum), Histoplasma
(e.g., Histoplasma capsulatum var. capsulatum), Malassezia (e.g.,
Malassezia furfur), Microsporum (e.g., Microsporum canis and
Microsporum gypseum), Mucor, Paracoccidioides (e.g.,
Paracoccidioides brasiliensis), Penicillium (e.g., Penicillium
marneffei), Phialophora, Pityrosporum ovale, Pneumocystis (e.g.,
Pneumocystis carinii), Pseudallescheria (e.g., Pseudallescheria
boydii), Rhizopus (e.g., Rhizopus microsporus var. rhizopodiformis
and Rhizopus oryzae), Saccharomyces (e.g., Saccharomyces
cerevisiae), Scedosporium (e.g., Scedosporium apiosperum),
Scopulariopsis, Sporothrix (e.g., Sporothrix schenckii),
Trichoderma, Trichophyton (e.g., Trichophyton mentagrophytes and
Trichophyton rubrum), and Trichosporon (e.g., Trichosporon asahii,
Trichosporon beigelii and Trichosporon cutaneum). The compounds are
not only useful against organisms causing systemic human pathogenic
mycotic infections, but also are useful against organisms causing
superficial fungal infections such as Trichoderma sp. and other
Candida spp. The compounds are particularly effective against
Aspergillus flavus, Aspergillus fumigatus, Candida albicans,
Candida parapsilosis, Cryptococcus neoformans, Saccharomyces
cerevisiae, and Trichophyton mentagrophytes.
[0084] In view of their antifungal activity, compounds of Formula
(I), (Ia), (II), and (IIa), and pharmaceutically acceptable salts
and/or hydrate forms thereof, are useful for the treatment and/or
prevention of one or more of a variety of superficial, cutaneous,
subcutaneous and systemic mycotic infections in skin, eye, hair,
nail, oral mucosa, gastrointestinal tract, bronchus, lung,
endocardium, brain, meninges, urinary organ, vaginal portion, oral
cavity, ophthalmus, systemic, kidney, bronchus, heart, external
auditory canal, bone, nasal cavity, paranasal cavity, spleen,
liver, hypodermal tissue, lymph duct, gastrointestine,
articulation, muscle, tendon, interstitial plasma cell in lung,
blood, and so on.
[0085] Therefore, compounds of Formula (I), (Ia), (II), and (IIa),
and pharmaceutically acceptable salts and/or hydrate forms thereof,
are useful for preventing and treating one or more of various
infectious diseases, such as dermatophytosis (e.g., trichophytosis,
ringworm or tinea infections), athletes foot, paronychia,
pityriasis versicolor, erythrasma, intertrigo, fungal diaper rash,
candida vulvitis, candida balanitis, otitis externa, candidiasis
(cutaneous and mucocutaneous), chronic mucocandidiasis (e.g. thrush
and vaginal candidiasis), cryptococcosis, geotrichosis,
trichosporosis, aspergillosis, penicilliosis, fusariosis,
zygomycosis, sporotrichosis, chromomycosis, coccidioidomycosis,
histoplasmosis, blastomycosis, paracoccidioidomycosis,
pseudallescheriosis, mycetoma, mycotic keratitis, otomycosis,
pneumocystosis, and fungemia. The compounds may also be used as
prophylactic agents to prevent systemic and topical fungal
infections. Use as prophylactic agents may, for example, be
appropriate as part of a selective gut decontamination regimen in
the prevention of infection in immuno-compromised patients (e.g.
AIDS patients, patients receiving cancer therapy or transplant
patients). Prevention of fungal overgrowth during antibiotic
treatment may also be desirable in some disease syndromes or
iatrogenic states.
[0086] The compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof, can
be made according to the synthesis methods disclosed in U.S. Pat.
No. 8,188,085, the contents of which are hereby incorporated by
reference herein in their entirety.
[0087] Examples of azoles that may be used in combination with the
compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof,
include but are not limited to: voriconazole, isavuconazole,
itraconazole, ketoconazole, miconazole, ravuconazole, detoconazole,
clotrimazole, and posaconazole. Examples of polyenes that may be
used in combination with the compounds of Formula (I), (Ia), (II),
and (IIa), and pharmaceutically acceptable salts and/or hydrate
forms thereof, include but are not limited to: amphotericin B,
nystatin, liposomal and lipid forms thereof such as ABELCET.RTM.,
AMBISOME.RTM., and AMPHOCIL.RTM.. Examples of purine or pyrimidine
nucleotide inhibitors that may be used in combination with the
compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof,
include but are not limited to: flucytosine or polyxins such as
nikkomycines, in particular nikkomycine Z or nikkomycine X. Chitin
inhibitors are another class of therapeutic agents that may be used
in combination with the compounds of Formula (I), (Ia), (II), and
(IIa), and pharmaceutically acceptable salts and/or hydrate forms
thereof. Examples of elongation factor inhibitors that may be used
in combination with the compounds of Formula (I), (Ia), (II), and
(IIa), and pharmaceutically acceptable salts and/or hydrate forms
thereof, include but are not limited to: sordarin and analogs
thereof. Examples of orotomides that may be used in combination
with the compounds of Formula (I), (la), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof,
include but are not limited to: F901318. Examples of Gwt1
inhibitors that may be used in combination with the compounds of
Formula (I), (Ia), (II), and (IIa), and pharmaceutically acceptable
salts and/or hydrate forms thereof, include but are not limited to:
APX001. Examples of pneumocandin or echinocandin derivatives that
may be used in combination with the compounds of Formula (I), (la),
(II), and (IIa), and pharmaceutically acceptable salts and/or
hydrate forms thereof, include but are not limited to: cilofungin,
anidulafungin, micafungin, and caspofungin. Examples of mannan
inhibitors that may be used in combination with the compounds of
Formula (I), (la), (II), and (IIa), and pharmaceutically acceptable
salts and/or hydrate forms thereof, include but are not limited to:
predamycin. Examples of bactericidal/permeability-inducing (BPI)
protein products that may be used in combination with the compounds
of Formula (I), (Ia), (II), and (IIa), and pharmaceutically
acceptable salts and/or hydrate forms thereof, include but are not
limited to: XMP.97 and XMP.127. Examples of immunomodulators that
may be used in combination with the compounds of Formula (I), (Ia),
(II), and (IIa), and pharmaceutically acceptable salts and/or
hydrate forms thereof, include but are not limited to: interferons
(e.g., IL-1, IL-2, IL-3 and IL-8), defensines, tacrolimus and G-CSF
(Granulocyte-colony stimulating factor).
[0088] As used herein, the term "alkyl" refers to any linear or
branched chain alkyl group having a number of carbon atoms in the
specified range. Thus, for example, "C.sub.1-6 alkyl" (or
"C.sub.1-C.sub.6 alkyl") refers to all of the hexyl alkyl and
pentyl alkyl isomers as well as n-, iso-, sec- and t-butyl, n- and
isopropyl, ethyl and methyl. As another example, "C.sub.1-4 alkyl"
refers to n-, iso-, sec- and t-butyl, n- and isopropyl, ethyl and
methyl.
[0089] The term "cycloalkyl" refers to any cyclic ring of an alkane
having a number of carbon atoms in the specified range. Thus, for
example, "C.sub.3-4 cycloalkyl" (or "C.sub.3-C.sub.4 cycloalkyl")
refers to cyclopropyl and cyclobutyl.
[0090] The term "cycloalkyl-alkyl" (or equivalently
"alkyl-cycloalkyl") as used herein refers to a system that includes
an alkyl portion as described above and also includes a cycloalkyl
portion as described above. Attachment to a "cycloalkyl-alkyl" (or
"alkyl-cycloalkyl") may be through either the cycloalkyl or the
alkyl portion. The specified number of carbon atoms in
"cycloalkyl-alkyl" systems refers to the total number of carbon
atoms in both the alkyl and the cycloalkyl parts. Examples of
C.sub.4-C.sub.5 cycloalkyl-alkyl include but are not limited to
methylcyclopropyl, dimethylcyclopropyl, methylcyclobutyl,
ethylcyclopropyl, cyclopropylmethyl, cyclopropylethyl and
cyclobutylmethyl.
[0091] The term "halogen" (or "halo") refers to fluorine, chlorine,
bromine and iodine (alternatively referred to as fluoro, chloro,
bromo, and iodo).
[0092] The term "or" as used herein denotes alternatives that may,
where appropriate, be combined.
[0093] Unless expressly stated to the contrary, all ranges cited
herein are inclusive. For example, a heterocyclic ring described as
containing from "1 to 4 heteroatoms" means the ring can contain 1,
2, 3, or 4 heteroatoms. It is also to be understood that any range
cited herein includes within its scope all of the sub-ranges within
that range. Thus, for example, a heterocyclic ring described as
containing from "1 to 4 heteroatoms" is intended to include as
aspects thereof, heterocyclic rings containing 2 to 4 heteroatoms,
3 or 4 heteroatoms, 1 to 3 heteroatoms, 2 or 3 heteroatoms, 1 or 2
heteroatoms, 1 heteroatom, 2 heteroatoms, and so forth.
[0094] Any of the various cycloalkyl and heterocyclic/heteroaryl
rings and ring systems defined herein may be attached to the rest
of the compound at any ring atom (i.e., any carbon atom or any
heteroatom) provided that a stable compound results. Suitable 5- or
6-membered heteroaromatic rings include, but are not limited to,
pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl and triazolyl.
[0095] A "stable" compound is a compound that can be prepared and
isolated and whose structure and properties remain or can be caused
to remain essentially unchanged for a period of time sufficient to
allow use of the compound for the purposes described herein (e.g.,
therapeutic or prophylactic administration to a subject). Reference
to a compound also includes stable complexes of the compound such
as a stable hydrate.
[0096] As a result of the selection of substituents and substituent
patterns, certain of the compounds of Formula (I), (Ia), (II), and
(IIa) can have asymmetric centers and can occur as mixtures of
stereoisomers, or as individual diastereomers, or enantiomers.
Unless otherwise indicated, all isomeric forms of these compounds
(and pharmaceutically acceptable salts and/or hydrate forms
thereof), whether isolated or in mixtures, are within the scope of
the present invention. Also included within the scope of the
present invention are tautomeric forms of the compounds as depicted
(and pharmaceutically acceptable salts and/or hydrate forms
thereof).
[0097] When any variable occurs more than one time in any
constituent or in Formula (I), (Ia), (II), or (IIa), its definition
on each occurrence is independent of its definition at every other
occurrence. Also, combinations of substituents and/or variables are
permissible only if such combinations result in stable
compounds.
[0098] The term "substituted" includes mono- and poly-substitution
by a named substituent to the extent such single and multiple
substitution (including multiple substitution at the same site) is
chemically allowed. Unless expressly stated to the contrary,
substitution by a named substituent is permitted on any atom in a
ring (e.g., an aryl, a cycloalkyl, a heteroaryl, or a heterocyclyl)
provided such ring substitution is chemically allowed and results
in a stable compound.
[0099] A bond terminated by a wavy line is used herein to signify
the point of attachment of a substituent group or partial
structure. This usage is illustrated by the following example:
##STR00006##
[0100] The compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof, are
also useful in the preparation and execution of screening assays
for antifungal compounds. For example, the compounds are useful for
isolating mutants, which are excellent screening tools for
identifying further antifungal compounds.
[0101] The compounds of Formula (I), (Ia), (II), and (IIa) may be
administered in the form of "pharmaceutically acceptable salts" or
hydrates as appropriate. Other salts may, however, be useful in the
preparation of the compounds or of their pharmaceutically
acceptable salts. For example, when the compounds contain a basic
amine group, they may be conveniently isolated as trifluoroacetic
acid salts (e.g., following HPLC purification). Conversion of the
trifluoroacetic acid salts to other salts, including
pharmaceutically acceptable salts, may be accomplished by a number
of standard methods known in the art. For example, an appropriate
ion exchange resin may be employed to generate the desired salt.
Alternatively, conversion of a trifluoroacetic acid salt to the
parent free amine may be accomplished by standard methods known in
the art (e.g., neutralization with an appropriate inorganic base
such as NaHCO.sub.3). Other desired amine salts may then be
prepared in a conventional manner by reacting the free base with a
suitable organic or inorganic acid. Representative pharmaceutically
acceptable quaternary ammonium salts include the following:
hydrochloride, sulfate, phosphate, carbonate, acetate, tartrate,
citrate, malate, succinate, lactate, stearate, fumarate, hippurate,
maleate, gluconate, ascorbate, adipate, gluceptate, glutamate,
glucoronate, propionate, benzoate, mesylate, tosylate, oleate,
lactobionate, laurylsulfate, besylate, caprylate, isetionate,
gentisate, malonate, napsylate, edisylate, pamoate, xinafoate,
napadisylate, hydrobromide, nitrate, oxalate, cinnamate, mandelate,
undecylenate, and camsylate. Many of the compounds of Formula (I),
(Ia), (II), and (IIa) carry an acidic carboxylic acid moiety, in
which case suitable pharmaceutically acceptable salts thereof may
include alkali metal salts, e.g., sodium or potassium salts;
alkaline earth metal salts, e.g., calcium or magnesium salts; and
salts formed with suitable organic ligands, e.g., quaternary
ammonium salts.
[0102] The present invention includes within its scope the use of
prodrugs of Formula (I), (Ia), (II), and (IIa). In general, such
prodrugs will be functional derivatives of the compounds, which are
readily convertible in vivo into the required compound. Thus, in
the methods of treatment of the present invention, the term
"administering" shall encompass the treatment of the various
conditions described with the compound specifically disclosed or
with a compound that converts to the specified compound in vivo
after administration to the patient. Conventional procedures for
the selection and preparation of suitable prodrug derivatives are
described, for example, in "Design of Prodrugs," ed. H. Bundgaard,
Elsevier, 1985, which is incorporated by reference herein in its
entirety. Metabolites of the compounds of Formula (I), (Ia), (II),
and (IIa) include active species produced upon introduction of the
compounds into the biological milieu.
[0103] The term "administration" and variants thereof (e.g.,
"administering" a compound) mean providing a compound or a prodrug
of the compound to the subject in need of treatment. When a
compound of Formula (I), (Ia), (II), and (IIa) or pharmaceutically
acceptable salt thereof or a hydrate or prodrug thereof is provided
in combination with a second active agent (e.g., other antifungal
and/or antibacterial agents useful for treating fungal and/or
bacterial infections), "administration" and its variants are each
understood to include concurrent and sequential provision of the
compound (or the salt, hydrate, or prodrug thereof) and of the
other active agent.
[0104] As used herein, the term "composition" is intended to
encompass a product comprising the specified ingredients, as well
as any product that results, directly or indirectly, from combining
the specified ingredients.
[0105] By "pharmaceutically acceptable" is meant that the
ingredients of the pharmaceutical composition must be compatible
with each other and not deleterious to the recipient thereof.
[0106] The term "subject" (alternatively referred to herein as
"patient") as used herein refers to an animal, preferably a mammal,
most preferably a human, who has been the object of treatment,
observation, or experiment.
[0107] The term "synergistic" refers to the effect of a compound of
Formula (I), (Ia), (II), or (IIa) or a pharmaceutically acceptable
salt thereof or a hydrate or prodrug thereof provided in
combination with a second active antifungal agent to prevent,
manage, or treat a disorder, which effect is better or more
beneficial or more pronounced than the additive effects of the
individual therapies. A synergistic effect of a combination of
therapies may permit the use of lower dosages of one or more of the
individual therapies and/or less frequent administration of the
therapies to a subject with a disorder. The ability to use lower
dosages of a therapy and/or to administer the therapy less
frequently reduces the toxicity associated with the administration
of the therapy to a subject without reducing the efficacy of the
therapy in the prevention or treatment of a disorder. In addition,
a synergistic effect can result in improved efficacy of agents in
the prevention or treatment of a disorder. Finally, a synergistic
effect of a combination of therapies may permit avoidance or
reduction of adverse or unwanted side effects associated with the
use of either therapy alone.
[0108] The term "effective amount" as used herein means an amount
of active ingredient or pharmaceutical agent that elicits the
biological or medicinal response in a tissue, system, animal, or
human that is being sought by a researcher, veterinarian, medical
doctor, or other clinician. In one embodiment, the "effective
amount" can be a therapeutically effective amount that alleviates
the symptoms of the disease or condition being treated. In another
embodiment, the "effective amount" can be a prophylactically
effective amount for prophylaxis of the symptoms of the disease or
condition being prevented or for reducing the likelihood of
occurrence. The term can also refer to an inhibition effect amount
of the enfumafungin derivative sufficient to inhibit
(1,3)-.beta.-D-glucan synthase and thereby elicit the response
being sought. The term can also refer to the amount of the second
antifungal agent, such as a mold-active agent, sufficient to
inhibit the growth of the mold. The term can also refer to the
amount of the enfumafungin derivative and the second agent that
when administered in combination is sufficient to inhibit the
growth of mold, and thereby elicit the response being sought (e.g.,
a therapeutically effective amount, a prophylactically effective
amount, or an inhibition effective amount). When the enfumafungin
derivatives and second antifungal agent are administered in a salt
form, references to the amounts of these compounds are to the free
acid or free base form of the compounds.
[0109] For the purpose of preventing or treating fungal infection,
the combination therapy comprising a first antifungal agent that is
compound of Formula (I), (Ia), (II), or (IIa) (optionally in the
form of a salt or a hydrate) and a second antifungal agent can be
administered in any way that that produces contact of the active
agent with the agent's site of action. The first and second agents
can be administered in conventional ways available for use in
conjunction with pharmaceuticals, either as individual therapeutic
agents or as a combination of therapeutic agents. They can be
administered alone, but in accordance with a typical practice can
be administered with a pharmaceutical carrier selected on the basis
of the chosen route of administration and standard pharmaceutical
practice. They can be administered simultaneously or sequentially
for a portion of or for the entire duration of the antifungal
regimen via any acceptable administration route appropriate for the
intended purpose. For example: the first and second agents can be
given intravenously, orally, or topically; or one intravenously and
other orally; or one orally and other topically; or in any
combination of administration routes as would be appropriate for
the fungal infection being treated or prevented. For instance: in
the case of invasive aspergillosis, the preferred route of
administration will be intravenously and/or orally; for a skin
fungal infection, the antifungal compounds can be administered both
topically or one orally and other topically; for an ocular fungal
infection, the antifungal agents can be administered both topically
or one intravenously or orally and the other topically. For
example, the compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically salts and/or hydrate forms thereof and the second
antifungal agent can be administered by one or more of the
following routes: orally, parenterally (including subcutaneous
injections, intravenous, intramuscular, intrasternal injection or
infusion techniques), by inhalation (e.g., nasal or buccal
inhalation spray, aerosols from metered dose inhalator, and dry
powder inhalator), by nebulizer, ocularly, topically,
transdermally, or rectally, in the form of a unit dosage of a
pharmaceutical composition containing an effective amount of the
compound and conventional non-toxic pharmaceutically-acceptable
carriers, adjuvants and vehicles. Liquid preparations suitable for
oral administration (e.g., suspensions, syrups, elixirs and the
like) can be prepared according to techniques known in the art and
can employ the usual media such as water, glycols, oils, alcohols
and the like. Solid preparations suitable for oral administration
(e.g., powders, pills, capsules and tablets) can be prepared
according to techniques known in the art and can employ such solid
excipients as starches, sugars, kaolin, lubricants, binders,
disintegrating agents and the like. Parenteral compositions can be
prepared according to techniques known in the art and typically
employ sterile water as a carrier and optionally other ingredients,
such as a solubility aid. Injectable solutions can be prepared
according to methods known in the art wherein the carrier comprises
a saline solution, a glucose solution or a solution containing a
mixture of saline and glucose.
[0110] Further description of methods suitable for use in preparing
pharmaceutical compositions and of ingredients suitable for use in
said compositions is provided in Remington's Pharmaceutical
Sciences, 20.sup.th edition, edited by A. R. Gennaro, Mack
Publishing Co., 2000.
[0111] The compounds of Formula (I), (Ia), (II), and (IIa), and
pharmaceutically acceptable salts and/or hydrate forms thereof, can
be administered, e.g., orally or intravenously, in a dosage range
of, for example, 0.001 to 1000 mg/kg of mammal (e.g., human) body
weight per day in a single dose or in divided doses. An example of
a dosage range is 0.01 to 500 mg/kg body weight per day orally or
intravenously in a single dose or in divided doses. Another example
of a dosage range is 0.1 to 100 mg/kg body weight per day orally or
intravenously in single or divided doses. For oral administration,
the compositions can be provided in the form of tablets or capsules
containing, for example, 1.0 to 1000 milligrams of the active
ingredient, particularly 1, 5, 10, 15, 20, 25, 50, 75, 100, 150,
200, 250, 300, 400, 500, 600, 750, and 1000 milligrams of the
active ingredient for the symptomatic adjustment of the dosage to
the patient to be treated. The specific dose level and frequency of
dosage for any particular patient may be varied and will depend
upon a variety of factors including the activity of the specific
compound employed, the metabolic stability and length of action of
that compound, the age, body weight, general health, sex, diet,
mode and time of administration, rate of excretion, drug
combination, the severity of the particular condition, and the host
undergoing therapy.
[0112] The second antifungal agent, including but not limited to
azoles or amphotericin B compounds, and their pharmaceutically
acceptable salts and/or hydrate forms thereof, can be administered
(e.g., orally or intravenously) in a dosage range of, for example,
0.001 to 1000 mg/kg of mammal (e.g., human) body weight per day in
a single dose or in divided doses, more preferably in a dose range
of 0.01 to 100 mg/kg. An example of a dosage range is 1 to 100
mg/kg body weight per day orally or intravenously in a single dose
or in divided doses. Another example of a dosage range includes
voriconazole administered at a range from 2 to 20 mg/kg per day
orally or intravenously in single or divided doses. Another example
of a dosage range includes amphotericin B administered at a range
from 0.2 to 10 mg/kg per day intravenously in single or divided
doses. For oral administration, the compositions can be provided in
the form of (e.g.) tablets, suspensions, solutions or capsules
containing, for example, 1.0 to 500 milligrams of the active
ingredient, particularly 50, 75, 100, 150, 200, 250, 300, 375, 400,
and 500 milligrams of the active ingredient for the symptomatic
adjustment of the dosage to the patient to be treated. The specific
dose level and frequency of dosage for any particular patient may
be varied and will depend upon a variety of factors including the
activity of the specific compound employed, the metabolic stability
and length of action of that compound, the age, body weight,
general health, sex, diet, mode and time of administration, rate of
excretion, drug combination, the severity of the particular
condition, and the host undergoing therapy. For intravenous
administration, the compositions can be provided in the form of
(e.g.) solutions, suspensions or other acceptable pharmaceutical
forms containing, for example, 1.0 to 500 milligrams of the active
ingredient. For topical administration, the second antifungal agent
can be provided as (e.g.) a cream, solution, ointment, foam,
powder, lacquer, emulsion or other pharmaceutically acceptable
forms containing, for example, 0.001 to 900 milligrams of the
active ingredient per gram of product.
[0113] Antifungal activity of compounds can be demonstrated by
various assays known in the art, for example, by their glucan
synthesis inhibitory activity (IC.sub.50), minimum inhibitory
concentration (MIC) and minimum effective concentration (MEC)
against filamentous molds and dermatophytes in a broth
microdilution assay, or in vivo anti-Aspergillus activity in a
mouse or rabbit models. The compounds of Formula (I) provided in
the Examples of U.S. Pat. No. 8,188,085 were generally found to
give an MEC against Aspergillus fumigatus in the range of
<0.03-32 .mu.g/mL.
Examples
[0114] The following examples serve only to illustrate the
invention and its practice. The examples are not to be construed as
limitations on the scope or spirit of the invention.
Combination Testing
[0115] Interactions between different drugs are described variously
as synergistic, indifferent, or antagonistic. Assessments of in
vitro drug interactions are usually based on the "no interaction"
theory, which assumes that drugs in combination do not interact
with each other and are therefore considered indifferent. When the
observed effect of the drug combination is more than that predicted
from the "no interaction" theory, synergy is claimed. On the other
hand, antagonism is claimed when the observed effect is less than
that predicted.
[0116] To determine the type of interaction between a
representative compound of the enfumafungin derivatives (SCY-078)
with several antifungal agents against Aspergillus fumigatus, the
most frequent mold causing invasive disease in humans, the
checkerboard method was used. The citrate salt of the compound was
used in the studies.
[0117] The checkerboard method involves the determination of
percent growth inhibition of fungal cells in the presence of
different combinations of drugs. Percent growth inhibition is
calculated relative to growth in control wells which contain only
cells and no drug. The assay was performed in 96-well microplates
in which each row and each column contained twofold serial
dilutions of drug A and drug B at concentrations ranging from 0 to
slightly higher than their minimum inhibitory concentration (MIC).
Each wall had a unique combination of the 2 drugs. Then the
inoculum was added to each well and the growth was evaluated after
48 hrs incubation to determine the first well in which growth was
inhibited. The checkerboard-based determination of MICs of
antifungal agents in combination was followed by further analysis
employing the nonparametric fractional inhibitory concentration
index (FICI), which is defined by the following equation:
FICI = ( MIC .times. .times. drug .times. .times. A .times. .times.
in .times. .times. combination MIC .times. .times. drug .times.
.times. A ) + ( MIC .times. .times. drug .times. .times. B .times.
.times. in .times. .times. combination MIC .times. .times. drug
.times. .times. B ) ##EQU00001##
where MIC-A and MIC-B are the MICs of drugs A and B, respectively.
According to the terminology of Odds (Odds, F. C. 2003. Synergy,
antagonism, and what the chequerboard puts between them. J.
Antimicrob. Chemother. 52:1), a FICI value of equal or lower than
0.5 is considered synergy, a FICI value of greater than 4.00 is
considered antagonism, and a FICI value between greater than 0.5 to
4.0 is considered no interaction.
[0118] Each drug was initially diluted in either sterile, distilled
water or in DMSO, depending on whether the drug was water-soluble
or water-insoluble, respectively. Since SCY-078 is not soluble in
water, a water-insoluble preparation was used.
[0119] Stock solution of SCY-078 was prepared in DMSO at 200 times
the concentration desired for use in the drug plates. Serial
dilutions of stock solution were conducted in DMSO to obtain eleven
2-fold dilutions of the drug. The SCY-078 solution was then diluted
to 4 times the desired concentration in RPMI-1640 medium so that
the DMSO would not limit growth of the organism and so that the
quantity of DMSO was the same for every dilution.
[0120] Two 96-well plates are needed to conduct a combination test.
Using a multichannel pipette, 50 .mu.l of the lowest concentration
of the first drug (Drug A) was added to each well of column 1 of
the first plate (plate A) and column 1 of the second plate (plate
B; rows A-D). Then, 50 .mu.l of the next highest working dilution
of Drug A was added to each well in column 2, continuing with
dilutions until all columns 1-11 were filled. Column 12 was left
empty. 50 .mu.l of the lowest concentration of Drug B was added to
each well in Row D of plate B. 50 .mu.l of the next highest working
dilution of Drug B was added to each well in row C of plate B,
continuing with dilutions until all rows through row B of plate A
were filled. Row A of plate A did not have any Drug B. 50 .mu.l
RPMI was added to row A and column 12 (well A-12 had 100 .mu.l of
straight RPMI).
[0121] Following the above, 100 .mu.l of organism inoculum was
added to every well. The plates were then incubated for 48 hours
and visually read after incubation.
[0122] The objective of the study was to determine whether the
combination of SCY-078 with voriconazole, isavuconazole, or
amphotericin B would result in a combined in vitro antifungal
activity exceeding the sum of the activities of each drug alone.
Combination MIC testing was performed using the checkerboard assay
described above.
Materials
[0123] Test Isolates: The following six clinical strains of
Aspergillus (4 wild-type and 2 resistant) were tested:
[0124] Wild-Type Strains
[0125] A. fumigatus MRL #20438
[0126] A. fumigatus MRL #28382
[0127] A. fumigatus MRL #28401
[0128] A. fumigatus MRL #28378
[0129] Resistant Strains
[0130] A. fumigatus MRL #28383
[0131] A. fumigatus MRL #28500
A. fumigatus 28500 has a CYP51 mutation at F46Y.
[0132] Antifungal Agents: The following combinations were
tested:
[0133] SCY-078+Voriconazole
[0134] SCY-078+Isavuconazole
[0135] SCY-078+Amphotericin B
[0136] A. fumigatus strains were obtained from the Mycology
Reference Library (MRL) at Case Western Reserve University School
of Medicine, Ohio, United States. SCY-078 was manufactured by
Avista Laboratories, North Carolina, United States. Voriconazole,
isavuconazole, and amphotericin B were sourced from commercial
distributors.
Methods
[0137] Initial MIC determinations of the individual antifungals
were performed according to the Clinical and Laboratory Standards
Institute (CLSI) M38-A2 standard for the susceptibility testing of
filamentous fungi.
[0138] Combination MIC testing was performed using a checkerboard
test method according to the Center for Medical Mycology SOP A11.3.
The checkerboard combination test method is a modification of the
microdilution antifungal susceptibility test wherein two test
compounds are combined in varying concentrations to determine
whether they have synergistic, antagonistic, or no effect on the
respective MIC values.
[0139] Antifungals were serially diluted two-fold in RPMI medium to
produce eleven concentrations each and were combined in wells of a
microtiter plate. Two rows consisting of serial dilutions of each
individual drug were included. All combination testing was
conducted in duplicate. Comparison of the MICs of the individual
drugs to the MIC of the combined agents is indicative of their
relative efficacy.
[0140] This interpretation followed the Antimicrobial Agents and
Chemotherapy guidelines, which seek to encourage conservative
interpretation of checkerboard combination data.
Results
[0141] Table 1 shows the FICI score and interpretation for SCY-078
in combination with isavuconazole against the azole sensitive and
resistant A. fumigatus isolates tested (tests were run in
duplicate). Against the susceptible isolates tested, the
combination of SCY-078 and isavuconazole demonstrated synergy in in
all four isolates tested. Against the resistant CYP51 mutant A.
fumigatus strain 28500 and the resistant strain 28383, SCY-078 in
combination with isavuconazole demonstrated no interaction.
[0142] Table 2 shows the FICI score and interpretation for SCY-078
in combination with voriconazole against the azole susceptible and
resistant A. fumigatus isolates tested (tests were run in
duplicate). Against the susceptible isolates tested, the
combination of SCY-078 and voriconazole demonstrated synergy
against all four isolates evaluated. The combination of SCY-078 and
voriconazole showed no interaction when tested against the
resistant A. fumigatus isolates.
[0143] Table 3 shows the FICI score and interpretation for SCY-078
in combination with amphotericin B against the azole susceptible
and resistant A. fumigatus isolates tested (tests were run in
duplicate). The combination of SCY-078 and amphotericin B
demonstrated synergy against all the susceptible isolates
evaluated. Against the resistant isolate, A. fumigatus 28383,
SCY-078 in combination with amphotericin B showed no interaction.
However, against the CYP51 mutant strain (A. fumigatus 28500),
SCY-078 in combination with amphotericin B demonstrated synergistic
activity.
TABLE-US-00001 TABLE 1 MIC values alone and in combination for
SCY-078 and isavuconazole against A. fumigatus (.mu.g/mL). MICs
were read at 48 hours and each test performed in duplicate. MIC per
drug in FICI Score MIC per drug Alone Combination SCY-078/ MRL
Organism SCY-078 Isavuconazole SCY-078 Isavuconazole Isavuconazole
Interpretation 20438 A. fumigatus 4 1 0.016 0.5 0.50 Synergistic 4
1 0.016 0.5 0.50 Synergistic 28378 A. fumigatus 4 1 0.125 0.125
0.16 Synergistic 4 1 0.125 0.25 0.28 Synergistic 28382 A. fumigatus
8 >8 0.016 0.25 0.03 Synergistic 4 1 0.063 0.25 0.27 Synergistic
28401 A. fumigatus 4 1 0.25 0.25 0.31 Synergistic 8 1 0.5 0.25 0.31
Synergistic *28383 A. fumigatus 4 >8 0.063 >8 1.02 No
interaction 4 >8 0.031 4 0.51 No interaction *28500 A. fumigatus
4 >8 1 >8 1.25 No interaction 4 >8 0.125 >8 1.03 No
interaction *Azole-resistant strains
TABLE-US-00002 TABLE 2 MIC values alone and in combination for
SCY-078 and voriconazole against A. fumigatus (.mu.g/mL). MICs were
read at 48 hours and each test performed in duplicate. MIC per drug
in FICI Score MIC per drug Alone Combination SCY-078/ MRL Organism
SCY-078 Voriconazole SCY-078 Voriconazole Voriconazole
Interpretation 20438 A. fumigatus 8 1 0.125 0.25 0.27 Synergistic 4
1 0.25 0.25 0.31 Synergistic 28378 A. fumigatus 8 0.5 0.5 0.125
0.31 Synergistic 4 0.25 0.5 0.016 0.19 Synergistic 28382 A.
fumigatus 8 0.5 0.5 0.125 0.31 Synergistic 8 0.5 0.016 0.25 0.50
Synergistic 28401 A. fumigatus 8 2 0.25 0.5 0.28 Synergistic 8 2
0.125 0.5 0.27 Synergistic *28383 A. fumigatus 8 >16 0.031
>16 1.00 No interaction 8 >16 0.031 >16 1.00 No
interaction *28500 A. fumigatus 4 >16 1 >16 1.25 No
interaction 8 >16 1 >16 1.13 No interaction *Azole-resistant
strains
TABLE-US-00003 TABLE 3 MIC values alone and in combination for
SCY-078 and amphotericin B against A. fumigatus (.mu.g/mL). MICs
were read at 48 hours and each test performed in duplicate. MIC per
drug in FICI Score MIC per drug Alone Combination SCY-078/ MRL
Organism SCY-078 Amphotericin B SCY-078 Amphotericin B Amphotericin
B Interpretation 20438 A. fumigatus 4 4 0.016 0.5 0.13 Synergistic
4 4 0.016 0.5 0.13 Synergistic 28378 A. fumigatus 4 2 0.016 0.5
0.25 Synergistic 4 2 0.016 0.5 0.25 Synergistic 28382 A. fumigatus
4 4 0.016 1 0.25 Synergistic 8 4 0.063 0.5 0.13 Synergistic 28401
A. fumigatus 4 4 0.016 1 0.25 Synergistic 8 4 0.031 0.5 0.13
Synergistic *28383 A. fumigatus 4 4 0.016 4 1.00 No interaction 4 2
0.125 2 1.03 No interaction *28500 A. fumigatus 4 4 0.016 1 0.25
Synergistic 4 4 0.125 1 0.28 Synergistic *Azole-resistant
strains
[0144] These data show that combinations of SCY-078 and
voriconazole, isavuconazole, and amphotericin B demonstrated
synergistic activity against all of the wild-type Aspergillus
fumigatus isolates tested. Combinations of SCY-078 and each of
voriconazole, isavuconazole, and amphotericin B demonstrated either
synergistic activity or no interaction against azole-resistant
Aspergillus fumigatus isolates tested.
[0145] Importantly, there was no antagonism demonstrated with these
combinations.
In Vivo Study
[0146] A study was conducted to evaluate the efficacy of the
combination of SCY-078 with isavuconazole. Isavuconazole is a
second generation antifungal triazole with activity against
Aspergillus spp. As described above, invasive pulmonary
aspergillosis is a life-threatening infection in immunosuppressed
patients-particularly those with severe and prolonged neutropenia
as a consequence of myelotoxic chemotherapy for the treatment of
cancer, and those receiving immunosuppressive medication for
rejection prophylaxis after organ transplantation or treatment of
graft-versus-host disease (GVHD) after allogeneic bone marrow
transplantation. A neutropenic rabbit model was selected for this
in vivo evaluation to further illustrate the effect of the
combination therapy of SCY-078 and an azole, in a relevant
immunosuppressed population.
Methods
[0147] New Zealand White rabbits weighing 2.5 to 3.5 kg (Covance
Research Products, Inc., Denver, Pa.) were used in this study.
Vascular access was established by the surgical placement of a
silastic tunneled central venous catheter. Cytosine arabinoside
(Cytosar-U) 525 mg/m.sup.2 was administered intravenously on days 1
through 5, and on days 8, 9, 13 and 14 to produce profound and
persistent neutropenia (a neutrophil concentration of <100
neutrophils/.mu.L). Methylprednisolone (Solu-Medrol.RTM., Pfizer,
NY) 5 mg/kg was administered on days 1 through 3 to inhibit
macrophage activity. Antibiotics (ceftazidime 75 mg/kg given
intravenously twice daily; gentamicin 5 mg/kg given intravenously
every other day; vancomycin 15 mg/kg given intravenously daily)
were used for prevention of opportunistic bacterial infections
during neutropenia.
[0148] Inoculum: NIH Aspergillus fumigatus isolate 4215 (ATCC No.
MY A-1163) obtained from a patient with a fatal case of pulmonary
aspergillosis was used in this study. The A. fumigatus isolate was
subcultured on potato dextrose agar slants (Remel Inc., Baltimore,
Md.), incubated for 24 h at 37.degree. C. and then kept at room
temperature for 5 days prior to use. On day 2 (i.e., 1 day after
the first dose of cytosine arabinoside), under direct
visualization, the inoculum (2.5.times.10.sup.8 A. fumigatus
conidia) was administered beyond the vocal cords into the
trachea.
[0149] Antifungal therapy: As outlined in Table 4, the following
six treatment groups were studied: a group receiving SCY-078 at 2.5
mg/kg/day (SCY2.5): a group receiving SCY-078 at 7.5 mg/kg/day
(SCY7.5); a group receiving isavuconazole at 40 mg/kg/day (ISA40);
a group receiving SCY-078 at 2.5 mg/kg/day and isavuconazole at 40
mg/kg/day (SCY2.5+ISA40); a group receiving SCY-078 at 7.5
mg/kg/day and isavuconazole at 40 mg/kg/day (SCY7.5+ISA40); and an
untreated control group (UC). Each group included six rabbits. The
antifungal agents, where administered, were administered
intravenously once a day. The citrate salt of SCY-078 was used. In
the groups receiving antifungal therapy, such administration
started 24 h after the endotracheal inoculation and was continued
once daily for 12 days. Surviving rabbits in the treated groups
were sacrificed 24 h after the last administration of antifungal
agent(s). No animals in the untreated group survived past day
8.
[0150] Evaluations: Survival, pulmonary infarct, and galactomannan
antigenemia (a serological marker of Aspergillus infection) were
evaluated as indicators of treatment response. After death or
sacrifice, the lungs were weighed and inspected by two blinded
observers for the presence of lesions of hemorrhagic infarction
typical of pulmonary aspergillosis. Blood from each rabbit was
collected every other day for determination of serum galactomannan
concentrations. Serum galactomannan concentrations were determined
by the Platelia.RTM. Aspergillus enzyme immunoassay (EIA) (Bio-Rad,
Marnes-la-Coquette, France) one-stage immunoenzymatic sandwich
microplate assay method. Enzyme immunoassay data were expressed as
a serum GMI (galactomannan index) plotted over time.
TABLE-US-00004 TABLE 4 Treatment Groups Group Treatment Dosage
Number No. Group (mg/kg/day) of animals 1 Untreated Control (UC) 0
6 2 SCY2.5 2.5 6 3 SCY7.5 7.5 6 4 ISA40 40 6 5 SCY2.5 + ISA40 2.5
and 40 6 6 SCY7.5 + ISA40 7.5 and 40 6 Total 36
Results
[0151] Survival was significantly increased in animals treated with
SCY7.5+ISA40 or SCY2.5+ISA40 in comparison to those receiving only
SCY-078 (SCY7.5 or SCY2.5) or only isavuconazole (ISA40) (FIG. 1).
Specifically, the rabbits receiving SCY7.5+ISA40 or SCY2.5+ISA40
had a survival rate, up to the day of scheduled sacrifice (day 13),
of 83% (5 out of 6 in each group), whereas the animals receiving
only ISA40 had a survival rate of 32% (2 out of 6); the animals
receiving only SCY2.5 had a survival rate of 16% (1 out of 6); and
the animals receiving only SCY7.5 and untreated controls had no
animals surviving until day 13. The markers of pulmonary injury
(pulmonary infarct score) demonstrated a similar pattern of
response (FIG. 2). Serum galactomannan antigenemia was noticeably
reduced in animals treated with SCY7.5+ISA40 or SCY2.5+ISA40 in
comparison to those treated with single agents (FIG. 3). The
combination of SCY-078 and isavuconazole was more effective in
reducing galactomannan levels than either agent by itself.
Moreover, the combination of SCY-078 and isavuconazole provided a
faster decline in galactomannan antigenemia than either agent by
itself.
[0152] This study further showed that the combination of SCY-078
with an azole was more efficacious and exhibited synergistic effect
in treating invasive pulmonary aspergillosis as compared with
either SCY-078 or the azole alone, in this model.
[0153] While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood in light of the present disclosure by those skilled
in the art that various changes in form and details may be made
therein without departing from the scope of the invention
encompassed by the appended claims.
* * * * *