U.S. patent application number 10/652962 was filed with the patent office on 2004-03-04 for crystal forms of azithromycin.
This patent application is currently assigned to Pfizer Inc. Invention is credited to Li, Zheng J., Trask, Andrew V..
Application Number | 20040043945 10/652962 |
Document ID | / |
Family ID | 27404135 |
Filed Date | 2004-03-04 |
United States Patent
Application |
20040043945 |
Kind Code |
A1 |
Li, Zheng J. ; et
al. |
March 4, 2004 |
Crystal forms of azithromycin
Abstract
The invention relates to novel crystal forms of azithromycin, an
antibiotic useful in the treatment of infections.
Inventors: |
Li, Zheng J.; (Quaker Hill,
CT) ; Trask, Andrew V.; (Stonington, CT) |
Correspondence
Address: |
PFIZER INC.
PATENT DEPARTMENT, MS8260-1611
EASTERN POINT ROAD
GROTON
CT
06340
US
|
Assignee: |
Pfizer Inc
|
Family ID: |
27404135 |
Appl. No.: |
10/652962 |
Filed: |
August 28, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10652962 |
Aug 28, 2003 |
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10152106 |
May 21, 2002 |
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60292565 |
May 22, 2001 |
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60297741 |
Jun 12, 2001 |
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60343041 |
Dec 21, 2001 |
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Current U.S.
Class: |
514/29 ;
536/7.4 |
Current CPC
Class: |
A61P 33/02 20180101;
C07H 17/00 20130101; A61P 33/00 20180101; A61K 9/2813 20130101;
A61P 31/04 20180101; A61K 9/1688 20130101; A61K 31/7052 20130101;
A61K 9/2866 20130101; C07H 17/08 20130101; A61K 9/2826
20130101 |
Class at
Publication: |
514/029 ;
536/007.4 |
International
Class: |
A61K 031/7052; C07H
017/08 |
Claims
What is claimed is:
1. A crystalline form of azithromycin selected from the group
consisting of forms D, E, substantially pure F, G, J, M
substantially in the absence of azithromycin dihydrate, N, O, P, Q,
and R.
2. A crystalline form of azithromycin according to claim 1 wherein
said form is form D.
3. A crystalline form according to claim 2 wherein said form is
characterized as containing 2-6% water and 3-12% cyclohexane by
weight in a powder sample.
4. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 2 and a pharmaceutically acceptable
excipient.
5. A crystalline form of azithromycin according to claim 2 wherein
said form is further characterized as having a .sup.13C solid state
NMR spectrum comprising a plurality of peaks with chemical shifts
of about 178.1 ppm, 103.9 ppm, 95.1 ppm, 84.2 ppm, 10.6 ppm, 9.0
ppm and 8.6 ppm.
6. A crystalline form of azithromycin according to claim 1 wherein
said form is form E.
7. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 6 and a pharmaceutically acceptable
excipient.
8. A crystalline form of azithromycin according to claim 1 wherein
said form is substantially pure form F.
9. A crystalline form according to claim 8 wherein said form is
characterized as containing 2-5% water and 1-5% ethanol by weight
in a powder sample.
10. A crystalline form of azithromycin according to claim 8 wherein
said form is further characterized as having a 13C solid state NMR
spectrum comprising a plurality of peaks with chemical shifts of
about 179.5 ppm, 178.6 ppm, 58.0 ppm, 17.2 ppm, 10.1 ppm 9.8 ppm,
9.3 ppm, 7.9 ppm and 6.6 ppm.
11. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises more than 80% by weight of form F
azithromycin.
12. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 81% or more by weight of form F
azithromycin.
13. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 82% or more by weight of form F
azithromycin.
14. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 83% or more by weight of form F
azithromycin.
15. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 84% or more by weight of form F
azithromycin.
16. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 85% or more by weight of form F
azithromycin.
17. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 86% or more by weight of form F
azithromycin.
18. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 87% or more by weight of form F
azithromycin.
19. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 88% or more by weight of form F
azithromycin.
20. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 89% or more by weight of form F
azithromycin.
21. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 90% or more by weight of form F
azithromycin.
22. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 91% or more by weight of form F
azithromycin.
23. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 92% or more by weight of form F
azithromycin.
24. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 93% or more by weight of form F
azithromycin.
25. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 94% or more by weight of form F
azithromycin.
26. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 95% or more by weight of form F
azithromycin.
27. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 96% or more by weight of form F
azithromycin.
28. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 97% or more by weight of form F
azithromycin.
29. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 98% or more by weight of form F
azithromycin.
30. A crystalline form of azithromycin according to claim 8 wherein
said azithromycin comprises 99% or more by weight of form F
azithromycin.
31. A pharmaceutical composition comprising a crystalline form of
azithromycin as in claim 8 or in one of claims 11-30 and a
pharmaceutically acceptable excipient
32. A crystalline form of azithromycin according to claim 1 wherein
said form is form G.
33. A crystalline form of azithromycin according to claim 1 wherein
said form is substantially pure form G.
34. A crystalline form according to claim 32 or claim 33 wherein
said form is characterized as containing 2-6% water and less than
1% organic solvent by weight in a powder sample.
35. A crystalline form of azithromycin according to claim 32 or
claim 33 wherein said form is further characterized as having a 13C
solid state NMR spectrum comprising a plurality of peaks with
chemical shifts of about 179.5 ppm, 10.4 ppm, 9.9 ppm, 9.3 ppm, 7.6
ppm and 6.5 ppm.
36. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises more than 50% by weight of form
G azithromycin.
37. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 55% or more by weight of form G
azithromycin.
38. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 60% or more by weight of form G
azithromycin.
39. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 65% or more by weight of form G
azithromycin.
40. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 70% or more by weight of form G
azithromycin.
41. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 75% or more by weight of form G
azithromycin.
42. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 80% or more by weight of form G
azithromycin.
43. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 85% or more by weight of form G
azithromycin.
44. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 90% or more by weight of form G
azithromycin.
45. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 91% or more by weight of form G
azithromycin.
46. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 92% or more by weight of form G
azithromycin.
47. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 93% or more by weight of form G
azithromycin.
48. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 94% or more by weight of form G
azithromycin.
49. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 95% or more by weight of form G
azithr6mycin.
50. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 96% or more by weight of form G
azithromycin.
51. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 97% or more by weight of form G
azithromycin.
52. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 98% or more by weight of form G
azithromycin.
53. A crystalline form of azithromycin according to claim 32
wherein said azithromycin comprises 99% or more by weight of form G
azithromycin.
54. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 32 or claim 33 or one of claims
36-53 and a pharmaceutically acceptable excipient
55. A crystalline form according to claim 1 wherein said form is
form H.
56. A crystalline form of azithromycin according to claim 55
wherein said form is further characterized as having a 13C solid
state NMR spectrum comprising a plurality of peaks with chemical
shifts of about 179.5 ppm, 178.7 ppm, 9.9 ppm, 9.1 ppm, 7.9 ppm and
7.0 ppm.
57. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 55 and a pharmaceutically
acceptable excipient
58. A crystalline form according to claim 1 wherein said form is
form J.
59. A crystalline form according to claim 58 wherein said form is
characterized as containing 2-5% water and 1-5% n-propanol by
weight in a powder sample.
60. A crystalline form according to claim 58 wherein said form is
further characterized as having a 13C solid state NMR spectrum
comprising a plurality of peaks with chemical shifts of about 179.6
ppm, 178.4 ppm, 25.2 ppm, 11.5 ppm, 10.0 ppm, 9.3 ppm, 8.1 ppm and
6.8 ppm.
61. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 58 and a pharmaceutically
acceptable excipient.
62. A crystalline form according to claim 1 wherein said form is
form M substantially in the absence of azithromycin dihydrate.
63. A crystalline form according to claim 62 wherein said form is
characterized as containing 2-5% water and 1-7% 2-propanol by
weight in a powder sample.
64. A crystalline form according to claim 62 wherein said form is
further characterized as having a 13C solid state NMR spectrum
comprising a plurality of peaks with chemical shifts of about 179.6
ppm, 41.9, 26.0 ppm, 16.3 ppm, 10.3 ppm, 9.6 ppm, 9.3 ppm, 7.7 ppm
and 7.1 ppm.
65. A crystalline form of azithromycin according to claim 62
wherein said azithromycin comprises less than 5% by weight of
azithromycin dihydrate.
66. A crystalline form of azithromycin according to claim 62
wherein said azithromycin comprises less than 4% by weight of
azithromycin dihydrate.
67. A crystalline form of azithromycin according to claim 62
wherein said azithromycin comprises less than 3% by weight of
azithromycin dihydrate.
68. A crystalline form of azithromycin according to claim 62
wherein said azithromycin comprises less than 2% by weight of
azithromycin dihydrate.
69. A crystalline form of azithromycin according to claim 62
wherein said azithromycin comprises less than 1% by weight of
azithromycin dihydrate.
70. A pharmaceutical composition comprising a crystalline form of
azithromycin according to one of claims 62-69 and a
pharmaceutically acceptable excipient.
71. A crystalline form according to claim 1 wherein said form is
form N.
72. A crystalline form according to claim 71 wherein said form is
characterized as containing 1-5% water and 2-5% organic solvent by
weight in a powder sample.
73. A crystalline form according to claim 71 wherein said form is
further characterized as having a 13C solid state NMR spectrum
comprising a plurality of peaks with chemical shifts of about 179.6
ppm, 178.7 ppm, 58.1 ppm, 26.0 ppm, 9.9 ppm, 9.4 ppm, 7.9 ppm, and
6.6 ppm.
74. A pharmaceutical composition comprising a crystalline form of
azithromycin according to one of claims 71-73 and a
pharmaceutically acceptable excipient.
75. A crystalline form according to claim 1 wherein said form is
form 0.
76. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 75 and a pharmaceutically
acceptable excipient.
77. A crystalline form according to claim 1 wherein said form is
form P.
78. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 87 and a pharmaceutically
acceptable excipient.
79. A crystalline form according to claim 1 wherein said form is
form Q.
80. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 79 and a pharmaceutically
acceptable excipient.
81. A crystalline form according to claim 1 wherein said form is
form R.
82. A crystalline form according to claim 81 wherein said form is
further characterized as having a 13C solid state NMR spectrum
having a plurality of peaks with chemical shifts of about 177.9
ppm, 95.3 ppm, 10.3 ppm, 9.6 ppm, 8.9 ppm, and 8.6 ppm.
83. A pharmaceutical composition comprising a crystalline form of
azithromycin according to claim 81 or 82 and a pharmaceutically
acceptable excipient.
84. An azithromycin mixture comprising azithromycin dihydrate and
one or more hydrate/solvates of azithromycin or azithromycin
sesquhydrate.
85. An azithromycin mixture according to claim 84 wherein the
hydrate/solvate contains a solvent selected from the group
consisting of ethanol, 2-propanol, n-propanol, formic acid,
butanol, pentanol, tetrahydrofuran, propylene glycol, acetone,
cyclohexane, and acetonitrile
86. An azithromycin mixture comprising azithromycin dihydrate and
one or more forms of azithromycin selected from the group
consisting of form D, form F, form G, form H, form J, form M, form
0, form Q and form R.
87. An azithromycin mixture according to claim 86 comprising form A
and form F.
88. An azithromycin mixture according to claim 86 comprising form A
and form G.
89. An azithromycin mixture according to claim 86 comprising form A
and form H.
90. An azithromycin mixture according to claim 86 comprising form A
and form J.
91. An azithromycin mixture according to claim 86 comprising form A
and form M.
92. An azithromycin mixture according to claim 86 comprising form A
and form F and form G.
93. An azithromycin mixture according to claim 86 comprising form A
and form G and form M.
94. A family of azithromycin crystalline forms wherein said family
is Family II.
95. The family of claim 64 wherein said family is characterized as
belonging to an orthorhombic P2.sub.12.sub.12.sub.1 space group
with cell dimensions of a=8.8.+-.0.4 .ANG., b=12.3.+-.0.5 .ANG. and
c=45.+-.0.5 .ANG..
96. A method of preparing the crystalline form of claim 2
comprising the step of slurrying azithromycin with cyclohexane and
isolating crystalline azithromycin.
97. A method of preparing the crystalline form of claim 8
comprising the steps of dissolving azithromycin in ethanol to form
an ethanol solution, cooling the ethanol solution to below
20.degree. C., precipitating azithromycin crystals and isolating
the crystals.
98. A method according to claim 97 wherein the ethanol solution is
cooled to 15.degree. C. or below.
99. A method according to claim 97 wherein the ethanol solution is
cooled to 10.degree. C. or below.
100. A method according to claim 97 wherein the ethanol solution is
cooled to 5.degree. C. or below.
101. A method as in one of claims 97-100 further comprising the
step of adding water to the ethanol solution after the ethanol
solution has been cooled.
102. A method according to claim 101 further comprising the step of
cooling the water prior to adding the water to the ethanol
solution.
103. A method according to claim 102 wherein the water is cooled to
below 20.degree. C.
104. A method according to claim 102 wherein the water is cooled to
15.degree. C. or below.
105. A method according to claim 102 wherein the water is cooled to
10.degree. C. or below.
106. A method according to claim 102 wherein the water is cooled to
50C or below.
107. A method according to one of claims 97 to 100 further
comprising the step of seeding the cooled ethanol solution with
crystals of form F azithromycin.
108. A method of preparing the crystalline form of claim 32
comprising the steps of dissolving azithromycin in a 1:1 mixture of
water and a solvent that is a member selected from the group
consisting of methanol, acetone, acetonitrile, adding water to the
mixture, precipitating azithromycin crystals and isolating the
crystals.
109. A method of preparing the crystalline form of claim 58
comprising the steps of dissolving azithromycin in n-propanol,
adding water, precipitating azithromycin crystals and isolating the
crystals.
110. A method of preparing the crystalline form of claim 62
comprising the steps of dissolving azithromycin with isopropanol to
form an isopropanol solution, cooling the isopropanol solution to
below 15.degree. C., adding water after the isopropanol solution
has been cooled, precipitating azithromycin crystals and isolating
the crystals.
111. A method according to claim 110 wherein the isopropanol
solution is cooled to 10.degree. C. or below.
112. A method according to claim 110 wherein the isopropanol
solution is cooled to 5.degree. C. or below.
113. A method according to one of claims 110 to 112 wherein the
water is cooled prior to adding the water to the isopropanol
solution.
114. A method according to claim 113 wherein the water is cooled to
20.degree. C. or below.
115. A method according to claim 113 wherein the water is cooled to
150C or below.
116. A method according to claim 113 wherein the water is cooled to
10.degree. C. or below.
117. A method according to claim 113 wherein the water is cooled to
50C or below.
118. A method according to claim 110 wherein the crystals are
isolated within 5 hours of precipitation.
119. A method according to claim 110 wherein the crystals are
isolated within 3 hours of precipitation.
120. A method according to claim 110 wherein the crystals are
isolated within 1 hour of precipitation.
121. A method according to claim 110 wherein the crystals are
isolated within 30 minutes of precipitation.
122. A method according to one of claims claim 110 to 112 further
comprising the step of seeding the cooled isopropanol solution with
crystals of the crystalline form of claim 62.
123. A method of treating a bacterial infection or a protozoa
infection in a mammal, fish, or bird which comprises administering
to said mammal, fish or bird a therapeutically effective amount of
crystalline azithromycin according to claim 1 or an azithromycin
mixture according to claim 86.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to crystal forms of azithromycin.
Azithromycin is sold commercially and is an effective antibiotic in
the treatment of a broad range of bacterial infections. The crystal
forms of this invention are likewise useful as antibiotic agents in
mammals, including man, as well as in fish and birds.
[0002] Azithromycin has the following structural formula: 1
[0003] Azithromycin is described and claimed in U.S. Pat. Nos.
4,517,359 and 4,474,768. It is also known as
9-deoxo-9a-aza-9a-methyl-9a-homoerytho- mycin A.
[0004] Other patents or patent applications which directly or
indirectly cover azithromycin include: EP 298,650 which claims
azithromycin dihydrate; U.S. Pat. No. 4,963,531 which claims a
method of treating a strain of Toxoplasma gondii species; U.S. Pat.
No. 5,633,006 which claims a chewable tablet or liquid suspension
pharmaceutical composition having reduced bitterness; U.S. Pat. No.
5,686,587 which claims an intermediate useful in the preparation of
azithromycin; U.S. Pat. No. 5,605,889 which claims an oral dosage
form that reduces the "food effect" associated with the
administration of azithromycin; U.S. Pat. No. 6,068,859 which
claims a controlled dosage form containing azithromycin; U.S. Pat.
No. 5,498,699 which claims a composition containing azithromycin in
combination with bivalent or trivalent metals; EP 925,789 which
claims a method of treating eye infections; Chinese patent
application CN 1123279A which relates to water soluble salts of
azithromycin; Chinese patent application CN 1046945C which relates
to azithromycin sodium dihydrogenphosphate double salts; Chinese
patent application CN 1114960A which relates to azithromycin
crystals, Chinese patent application CN 1161971A which relates to
azithromycin crystals; Chinese patent application CN 1205338A which
relates to a method of preparing water soluble salts of
azithromycin; International Publication WO 00/32203 which relates
to an ethanolate of azithromycin; and European patent application
EP 984,020 which relates to an azithromycin monohydrate isopropanol
clathrate.
SUMMARY OF THE INVENTION
[0005] The present invention relates to crystal forms of
azithromycin. As used herein, the term "crystal form(s)" or
"form(s)", unless otherwise noted, means one or more crystal forms
of azithromycin.
[0006] In particular, the present invention relates to a crystal
form of azithrocmycin wherein said crystal form is selected from
forms C, D, E, F, G, H, J, M, N, 0, P, Q and R wherein said forms
are as defined herein. Forms F, G, H, J, M, N, O, and P belong to
family I azithromycin and belong to a monoclinic P2, space group
with cell dimensions of a=16.3.+-.0.3 .ANG., b=16.2.+-.0.3 .ANG.,
c=18.4.+-.0.3 .ANG. and beta=109.+-.2.degree.. Forms C, D, E and R
belong to family II azithromycin and belong to an orthorhombic
P2.sub.1 2.sub.12.sub.1 space group with cell dimensions of
a=8.9.+-.0.4 .ANG., b=12.3.+-.0.5 .ANG. and c=45.8.+-.0.5 .ANG..
Form Q is distinct from families I and II.
[0007] Form F azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.0.5C.sub.2H.sub.5OH in
the single crystal structure, being azithromycin monohydrate
hemi-ethanol solvate. Form F is further characterized as containing
2-5% water and 1-4% ethanol by weight in powder samples and having
powder X-ray diffraction 2.theta. peaks as defined in Table 9. The
.sup.13C ssNMR (solid state Nuclear Magnetic Resonance) spectrum of
form F has two chemical shift peaks at approximately 179.+-.1 ppm,
those being 179.5.+-.0.2 ppm and 178.6.+-.0.2 ppm, a set of five
peaks between 6.4 to 11.0 ppm, and ethanol peaks at 58.0.+-.0.5 ppm
and 17.2.+-.0.5 ppm. The solvent peaks can be broad and relatively
weak in intensity.
[0008] The invention also relates to substantially pure form F
azithromycin, form F azithromycin substantially free of form G
azithromycin and form F azithromycin substantially free of
azithromycin dihydrate.
[0009] The invention further relates to methods of preparing form F
azithromycin by treating azithromycin with ethanol to complete
dissolution at 40-70.degree. C. and cooling with reduction of
ethanol or addition of water to effect crystallization. Also
included are methods of making substantially pure form F
azithromycin, form F azithromycin substantially free of form G
azithromycin and form F azithromycin substantially free of
azithromycin dihydrate.
[0010] Form G azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.1.5H.sub.2O in the single crystal
structure, being azithromycin sesquihydrate. Form G is further
characterized as containing 2.5-6% water and <1% organic
solvent(s) by weight in powder samples and having powder X-ray
diffraction 2.theta. peaks as defined in Table 9. The .sup.13C
ssNMR spectrum of form G has one chemical shift peak at
approximately 179.+-.1 ppm, being a peak at 179.5.+-.0.2 ppm
(splitting <0.3 ppm may present), and a set of five peaks
between 6.3 to 11.0 ppm.
[0011] The invention also relates to substantially pure form G
azithromycin, and form G azithromycin substantially free of
azithromycin dihydrate.
[0012] The invention further relates to methods of preparing
substantially pure form G azithromycin, and form G azithromycin
substantially free of azithromycin dihydrate by treating
azithromycin with a mixture of methanol and water or acetone and
water to complete dissolution at 40-60.degree. C. and cooling to
effect crystallization.
[0013] Form H azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.C.sub.3H.sub.8O.sub.2
being azithromycin monohydrate hemi-1,2 propanediol solvate.
[0014] Form J azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.0.5C.sub.3H.sub.7OH in
the single crystal structure, being azithromycin monohydrate
hemi-n-propanol solvate. Form J is further characterized as
containing 2-5% water and 1-5% 1-propanol by weight in powder
samples and having powder X-ray diffraction 2.theta. peaks as
defined in Table 9. The .sup.13C ssNMR spectrum of form J has two
chemical shift peaks at approximately 179.+-.1 ppm, those being
179.6.+-.0.2 ppm and 178.4.+-.0.2 ppm, a set of five peaks between
6.6 to 11.7 ppm and an n-propanol peak at 25.2.+-.0.4 ppm. The
solvent peak can be broad and relatively weak in intensity.
[0015] The invention further relates to methods of preparing form J
by treating azithromycin with n-propanol to complete dissolution at
25-55.degree. C. and cooling with addition of water to effect
crystallization.
[0016] Form M azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.0.5C.sub.3H.sub.7OH,
being azithromycin monohydrate hemi-isopropanol solvate. Form M is
further characterized as containing 2-5% water and 1-4% 2-propanol
by weight in powder samples and having powder X-ray diffraction
2.theta. peaks as defined in Table 9. The .sup.13C ssNMR spectrum
of form M has one chemical shift peak at approximately 179.+-.1
ppm, being 179.6.+-.0.2 ppm, a peak at 41.9.+-.0.2 ppm and a set of
six peaks between 6.9 to 16.4 ppm and an isopropanol peak at
26.0.+-.0.4 ppm. The solvent peak can be broad and relatively weak
in intensity.
[0017] The invention also relates to substantially pure form M
azithromycin, form M azithromycin substantially free of form G
azithromycin and form M azithromycin substantially free of
azithromycin dihydrate.
[0018] The invention further relates to methods of preparing
substantially pure form M azithromycin, form M azithromycin
substantially free of form G azithromycin and form M azithromycin
substantially free of azithromycin dihydrate by treating
azithromycin with isopropanol to complete dissolution at
40-60.degree. C. and reduction of isopropanol followed by cooling
or cooling followed by addition of water to effect
crystallization.
[0019] Form N azithromycin is a mixture of isomorphs of Family I.
The mixture may contain variable percentages of isomorphs, F, G, H,
J, M and others, and variable amounts of water and organic
solvents, such as ethanol, isopropanol, n-propanol, propylene
glycol, acetone, acetonitrile, butanol, pentanol, etc. The weight
percent of water can range from 1-5% and the total weight percent
of organic solvents can be 2-5% with each solvent content of 0.5 to
4%. The samples of form N display all characteristic peaks of
members of Family I in various proportions. Form N may be
characterized as `mixed crystals` or "crystalline solid solutions`
of Family I isomorphs.
[0020] Form N displays chemical shifts as a combination of
isomorphs in Family I. The peaks may vary in chemical shift ppm
within .+-.0.2 ppm and in relative intensities and width due to the
mixing of variable proportion of isomorphs contained in the form N
crystalline solid solution.
[0021] Form P azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.0.5C.sub.5H.sub.2O being
azithromycin monohydrate hemi-n-pentanol solvate.
[0022] Form Q azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.0.5C.sub.4H.sub.8O being
azithromycin monohydrate hemi-tetrahydrofuran solvate.
[0023] Form R azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.C.sub.5H.sub.12O being
azithromycin monohydrate mono-methyl tert-butyl ether solvate.
[0024] Form D azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.C.sub.6H.sub.12 in its
single crystal structure, being azithromycin monohydrate
monocyclohexane solvate. Form D is further characterized as
containing 2-6% water and 3-12% cyclohexane by weight in powder
samples and having representative powder X-ray diffraction 2.theta.
peaks as defined in Table 9. The .sup.13C ssNMR spectrum of form D
displays has one chemical shift peak at approximately 179.+-.1 ppm,
being 178.1.+-.0.2 ppm and peaks at 103.9.+-.0.2 ppm, 95.1.+-.0.2
ppm, 84.2.+-.0.2 ppm, and a set of 3 peaks between 8.4 to 11
ppm.
[0025] The invention further relates to methods of preparing form D
by slurrying azithromycin dihydrate with cyclohexane.
[0026] Form E azithromycin is of the formula
C.sub.38H.sub.72N.sub.2O.sub.- 12.H.sub.2O.C.sub.4H.sub.8O being
azithromycin monohydrate mono-tetrahydrofuran solvate.
[0027] The invention further relates to azithromycin in an
amorphous state and a method of preparing amorphous azithromycin
that comprises the removal of water and/or solvents from the
azithromycin crystal lattice. The X-ray diffraction powder pattern
for amorphous azithromycin displays no sharp 20 peaks but has two
broad rounded peaks. The first peak occurs between 40 and
13.degree.. The second peak occurs between 130 and 25.degree..
[0028] The invention also relates to pharmaceutical compositions
for the treatment of a bacterial infection or a protozoa infection
in a mammal, fish, or bird which comprises a therapeutically
effective amount of the crystalline compounds referred to above, or
amorphous azithromycin, and a pharmaceutically acceptable
carrier.
[0029] The invention also relates to a method of treating a
bacterial infection or a protozoa infection in a mammal, fish, or
bird which comprises administering to said mammal, fish or bird a
therapeutically effective amount of the crystalline compounds
referred to above, or amorphous azithromycin.
[0030] The present invention also relates to methods of preparing
crystal forms of azithromycin which comprise the slurrying of
azithromycin in an appropriate solvent or the dissolution of
azithromycin in a heated organic solvent or organic solvent/water
solution and precipitating the crystalline azithromycin by cooling
the solution with reduction of solvent volume or by dissolving
azithromycin in a solvent or solvent mixture and precipitating
crystalline azithromycin by the addition of water to the solution.
Azithromycin in amorphous state is prepared by heating crystalline
azithromycin a vacuum.
[0031] The term "treatment", as used herein, unless otherwise
indicated, means the treatment or prevention of a bacterial
infection or protozoa infection as provided in the method of the
present invention, including curing, reducing the symptoms of or
slowing the progress of said infection. The terms "treat" and
"treating" are defined in accord the foregoing term
"treatment".
[0032] The term "substantially free" when referring to a designated
crystalline form of azithromycin means that there is less than 20%
(by weight) of the designated crystalline form(s) present, more
preferably, there is less than 10% (by weight) of the designated
form(s) present, more preferably, there is less than 5% (by weight)
of the designated form(s) present, and most preferably, there is
less than 1% (by weight) of the designated crystalline form(s)
present. For instance, form F azithromycin substantially free of
azithromycin dihydrate means form F with 20% (by weight) or less of
azithromycin dihydrate, more preferably, 10% (by weight) or less of
azithromycin dihydrate, most preferably, 1% (by weight) of
azithromycin dihydrate.
[0033] The term "substantially pure" when referring to a designated
crystalline form of azithromycin means that the designated
crystalline form contains less than 20% (by weight) of residual
components such as alternate polymorphic or isomorphic crystalline
form(s) of azithromycin. It is preferred that a substantially pure
form of azithromycin contain less than 10% (by weight) of alternate
polymorphic or isomorphic crystalline forms of azithromycin, more
preferred is less than 5% (by weight) of alternate polymorphic or
isomorphic crystalline forms of azithromycin, and most preferably
less than 1% (by weight) of alternate polymorphic or isomorphic
crystalline forms of azithromycin.
[0034] The term "substantially in the absence of azithromycin
dihydrate" when referring to bulk crystalline azithromycin or a
composition containing crystalline azithromycin means the
crystalline azithromycin contains less than about 5% (by weight)
azithromycin dehydrate, more preferably less than about 3% (by
weight) azithromycin dihydrate, and most preferably less than 1%
(by weight) azithromycin dihydrate.
[0035] As used herein, unless otherwise indicated, the term
"bacterial infection(s)" or "protozoa infection" includes bacterial
infections and protozoa infections and diseases caused by such
infections that occur in mammals, fish and birds as well as
disorders related to bacterial infections and protozoa infections
that may be treated or prevented by administering antibiotics such
as the compound of the present invention. Such bacterial infections
and protozoa infections and disorders related to such infections
include, but are not limited to, the following: pneumonia, otitis
media, sinusitus, bronchitis, tonsillitis, and mastoiditis related
to infection by Streptococcus pneumoniae, Haemophilus influenzae,
Moraxella catarrhalis, Staphylococcus aureus, or Peptostreptococcus
spp.; pharynigitis, rheumatic fever, and glomerulonephritis related
to infection by Streptcoccus pyogenes, Groups C and G streptococci,
Clostridium diptheriae, or Actinobacillus haemolyticum; respiratory
tract infections related to infection by Mycoplasma pneumoniae,
Legionella pneumophila, Streptococcus pneumoniae, Haemophilus
influenzae, or Chlamydia pneumoniae; uncomplicated skin and soft
tissue infections, abscesses and osteomyelitis, and puerperal fever
related to infection by Staphylococcus aureus, coagulase-positive
staphylococci (i.e., S. epidermidis, S. hemolyticus, etc.),
Streptococcus pyogenes, Streptococcus agalactiae, Streptococcal
groups C-F (minute-colony streptococci), viridans streptococci,
Corynebacterium minutissimum, Clostridium spp., or Bartonella
henselae; uncomplicated acute urinary tract infections related to
infection by Staphylococcus saprophyticus or Enterococcus spp.;
urethritis and cervicitis; and sexually transmitted diseases
related to infection by Chlamydia trachomatis, Haemophilus ducreyi,
Treponema pallidum, Ureaplasma urealyticum, or Neiserria
gonorrheae; toxin diseases related to infection by S. aureus (food
poisoning and Toxic shock syndrome), or Groups A, B, and C
streptococci; ulcers related to infection by Helicobacter pylori;
systemic febrile syndromes related to infection by Borrelia
recurrentis; Lyme disease related to infection by Borrelia
burgdorferi; conjunctivitis, keratitis, and dacrocystitis related
to infection by Chlamydia trachomatis, Neisseria gonorrhoeae, S.
aureus, S. pneumoniae, S. pyogenes, H. influenzae, or Listeria
spp.; disseminated Mycobacterium avium complex (MAC) disease
related to infection by Mycobacterium avium, or Mycobacterium
intracellulare; gastroenteritis related to infection by
Campylobacter jejuni; intestinal protozoa related to infection by
Cryptosporidium spp.; odontogenic infection related to infection by
viridans streptococci; persistent cough related to infection by
Bordetella pertussis; gas gangrene related to infection by
Clostridium perfringens or Bacteroides spp.; and atherosclerosis
related to infection by Helicobacter pylori or Chiamydia
pneumoniae. Also included are atherosclerosis and malaria.
Bacterial infections and protozoa infections and disorders related
to such infections that may be treated or prevented in animals
include, but are not limited to, the following: bovine respiratory
disease related to infection by P. haem., P. multocida, Mycoplasma
bovis, or Bordetella spp.; cow enteric disease related to infection
by E. coli or protozoa (i.e., coccidia, cryptosporidia, etc.);
dairy cow mastitis related to infection by Staph. aureus, Strep.
uberis, Strep. agalactiae, Strep. dysgalactiae, Klebsiella spp.,
Corynebacterium, or Enterococcus spp.; swine respiratory disease
related to infection by A. pleuro., P. multocida, or Mycoplasma
spp.; swine enteric disease related to infection by E. coli,
Lawsonia intracellularis, Salmonella, or Serpulina hyodyisinteriae;
cow footrot related to infection by Fusobacterium spp.; cow
metritis related to infection by E. coli; cow hairy warts related
to infection by Fusobacterium necrophorum or Bacteroides nodosus;
cow pink-eye related to infection by Moraxella bovis; cow premature
abortion related to infection by protozoa (i.e. neosporium);
urinary tract infection in dogs and cats related to infection by E.
coli; skin and soft tissue infections in dogs and cats related to
infection by Staph. epidermidis, Staph. intermedius, coagulase neg.
Staph. or P. multocida; and dental or mouth infections in dogs and
cats related to infection by Alcaligenes spp., Bacteroides spp.,
Clostridium spp., Enterobacter spp., Eubacterium,
Peptostreptococcus, Porphyromonas, or Prevotella. Other bacterial
infections and protozoa infections and disorders related to such
infections that may be treated or prevented in accord with the
method of the present invention are referred to in J. P. Sanford et
al., "The Sanford Guide To Antimicrobial Therapy," 26th Edition,
(Antimicrobial Therapy, Inc., 1996).
[0036] The present invention also includes isotopically-labeled
compounds wherein one or more atoms are replaced by an atom having
an atomic mass or mass number different from the atomic mass or
mass number usually found in nature. Examples of isotopes that can
be incorporated into compounds of the invention include isotopes of
hydrogen, carbon, nitrogen, oxygen, phosphorous, sulfur, fluorine
and chlorine, such as .sup.2H, .sup.3H, .sup.13C, .sup.14C,
.sup.15N, .sup.18O, and .sup.17O. Such radiolabelled and
stable-isotopically labelled compounds are useful as research or
diagnostic tools.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a calculated powder X-ray diffraction pattern of
azithromycin form A. The scale of the abscissa is degrees 2-theta
(2.theta.). The ordinate is the intensity in counts.
[0038] FIG. 2 is an experimental powder X-ray diffraction pattern
of azithromycin form A. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0039] FIG. 3 is an overlay of FIGS. 1 and 2 with the calculated
diffraction patterns of azithromycin form A (FIG. 1) on the bottom
and the experimental diffraction pattern of azithromycin form A
(FIG. 2) on the top. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0040] FIG. 4 is a calculated powder X-ray diffraction pattern of
azithromycin form C. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0041] FIG. 5 is a calculated powder X-ray diffraction pattern of
azithromycin form D. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0042] FIG. 6 is an experimental powder X-ray diffraction pattern
of azithromycin form D. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0043] FIG. 7 is an overlay of FIGS. 5 and 6 with the calculated
diffraction pattern of azithromycin form D (FIG. 5) on the bottom
and the experimental diffraction pattern of azithromycin form D
(FIG. 6) on the top. The scale of the abscissa is in degrees
2-theta (2 0). The ordinate is the intensity in counts.
[0044] FIG. 8 is a calculated powder X-ray diffraction pattern of
azithromycin form E. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0045] FIG. 9 is a calculated powder X-ray diffraction pattern of
azithromycin form F. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0046] FIG. 10 is an experimental powder X-ray diffraction pattern
of azithromycin form F. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0047] FIG. 11 is an overlay of FIGS. 9 and 10 with the calculated
diffraction pattern of azithromycin form F (FIG. 9) on the bottom
and the experimental diffraction pattern of azithromycin form F
(FIG. 10) on the top. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0048] FIG. 12 is a calculated powder X-ray diffraction pattern of
azithromycin form G. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity is counts.
[0049] FIG. 13 is an experimental powder X-ray diffraction pattern
of azithromycin form G. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0050] FIG. 14 is an overlay of FIGS. 12 and 13 with the calculated
diffraction pattern of azithromycin form G (FIG. 12) on the bottom
and the experimental diffraction pattern of azithromycin form G
(FIG. 13) on the top. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0051] FIG. 15 is a calculated powder X-ray diffraction pattern of
azithromycin form J. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0052] FIG. 16 is an experimental powder X-ray diffraction pattern
of azithromycin form J. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0053] FIG. 17 is an overlay of FIGS. 15 and 16 with the calculated
diffraction pattern of azithromycin form J (FIG. 15) on the bottom
and the experimental diffraction pattern of azithromycin form J
(FIG. 16) on the top. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0054] FIG. 18 is an experimental powder X-ray diffraction pattern
of azithromycin form M. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0055] FIG. 19 is an experimental powder X-ray diffraction pattern
of azithromycin form N. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0056] FIG. 20 is an experimental powder X-ray diffraction pattern
of amorphous azithromycin. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0057] FIG. 21 is a .sup.13C solid state NMR spectrum of
azithromycin form A.
[0058] FIG. 22 is a .sup.13C solid state NMR spectrum of
azithromycin form D.
[0059] FIG. 23 is a .sup.13C solid state NMR spectrum of
azithromycin form F.
[0060] FIG. 24 is a .sup.13 solid state NMR spectrum of
azithromycin form G. FIG. 25 is a .sup.13C solid state NMR spectrum
of azithromycin form J.
[0061] FIG. 26 is a .sup.13C solid state NMR spectrum of
azithromycin form M.
[0062] FIG. 27 is a .sup.13C solid state NMR spectrum of
azithromycin form N.
[0063] FIG. 28 is a .sup.13C solid state NMR spectrum of amorphous
azithromycin.
[0064] FIG. 29 is a .sup.13C solid state NMR spectrum of a
pharmaceutical tablet containing form G azithromycin.
[0065] FIG. 30 is an experimental powder X-ray diffraction pattern
of azithromycin form Q. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0066] FIG. 31 is an experimental powder X-ray diffraction pattern
of azithromycin form R. The scale of the abscissa is in degrees
2-theta (2.theta.). The ordinate is the intensity in counts.
[0067] FIG. 32 is a .sup.13C solid state NMR spectrum of
azithromycin form H.
[0068] FIG. 33 is a .sup.13C solid state NMR spectrum of
azithromycin form R.
DETAILED DESCRIPTION OF THE INVENTION
[0069] Azithromycin has been found to exist in different
crystalline forms. A dihydrate, form A, and a non-stroichiometric
hydrate, form B, are disclosed in European Patent EP 298 650 and
U.S. Pat. No. 4,512,359, respectively. Sixteen other forms have
been discovered, namely forms C, D, E, F, G, H, l, J, K, L, M, N,
O, P, Q and R. These forms are either hydrates or hydrate/solvates
of azithromycin free base. Forms L and K are the metastable lower
hydrate forms of A, detected at high temperature. Crystal
structures of forms A, C, D, E, F, G, H, J and O have been solved.
The structural data of these crystal forms are given below:
1TABLE 1 Crystallographic data of azithromycin form A. Form A
Empirical formula C.sub.38H.sub.72N.sub.2O.sub.12.2H.sub.2O Formula
weight 785.2 Crystal size (mm) 0.19 .times. 0.24 .times. 0.36 Space
group P2.sub.12.sub.12.sub.1 orthorhombic Unit cell dimensions a =
14.735 (5) .ANG. b = 16.844 (7) .ANG. c = 17.81 (1) .ANG. .alpha. =
90.degree. .beta. = 90.degree. .gamma. = 90.degree. Z (per formula)
4 Density (g/cm.sup.3) 1.18 R 0.060
[0070]
2TABLE 2 Crystallographic data of azithromycin form C. Form C
Empirical formula C.sub.38H.sub.72N.sub.2O.sub.12.H.sub.2O Formula
weight 767.15 Crystal size (mm) 0.16 .times. 0.16 .times. 0.19
Space group P2.sub.12.sub.12.sub.1 orthorhombic Unit cell
dimensions a = 8.809 (3) .ANG. b = 12.4750 (8) .ANG. c = 45.59 (3)
.ANG. .alpha. = 90.degree. .beta. = 90.degree. .gamma. = 90.degree.
Z (per formula) 4 Density (g/cm.sup.3) 1.01 R 0.106
[0071]
3TABLE 3 Crystallographic data of azithromycin form D. Form D
Empirical formula
C.sub.38H.sub.72N.sub.2O.sub.12.H.sub.2O.C.sub.6H.sub.12 Formula
weight 851.15 Crystal size (mm) 0.52 .times. 0.32 .times. 0.16
Space group P2.sub.12.sub.12.sub.1 orthorhombic Unit cell
dimensions a = 8.8710 (10) .ANG. b = 12.506 (2) .ANG. c = 45.697
(7) .ANG. .alpha. = 90.degree. .beta. = 90.degree. .gamma. =
90.degree. Z (per formula) 4 Density (g/cm.sup.3) 1.12 R 0.0663
[0072]
4TABLE 4 Crystallographic data of azithromycin form E. Form E
Empirical formula
C.sub.38H.sub.72N.sub.2O.sub.12.H.sub.2O.C.sub.4H.sub.8O Formula
weight 839.2 Crystal size (mm) 0.17 .times. 0.19 .times. 0.20 Space
group P2.sub.12.sub.12.sub.1 orthorhombic Unit cell dimensions a =
8.869 (3) .ANG. b = 12.086 (3) .ANG. c = 46.00 (1) .ANG. .alpha. =
90.degree. .beta. = 90.degree. .gamma. = 90.degree. Z (per formula)
4 Density (g/cm.sup.3) 1.13 R 0.087
[0073]
5TABLE 5 Crystallographic data of azithromycin form F. Form F
Empirical formula
C.sub.38H.sub.72N.sub.2O.sub.12.H.sub.2O.0.5C.sub.2H.sub.6O Crystal
size (mm) 0.14 .times. 0.20 .times. 0.24 Formula weight 790.2 Space
group P2.sub.1 monoclinic Unit cell dimensions a = 16.281 (2) .ANG.
b = 16.293 (1) .ANG. c = 18.490 (3) .ANG. .alpha. = 90.degree.
.beta. = 109.33 (1).degree. .gamma. = 90.degree. Z (per formula) 4
Density (g/cm.sup.3) 1.13 R 0.0688
[0074]
6TABLE 6 Crystallographic data of azithromycin form G. Form G
Formula C.sub.38H.sub.72N.sub.2O.sub.1- 2.1.5H.sub.2O Formula
weight 776.0 Crystal size (mm) 0.04 .times. 0.20 .times. 0.24 Space
group P2.sub.1 monoclinic Unit cell dimensions a = 16.4069 (8)
.ANG. b = 16.2922 (8) .ANG. c = 18.3830 (9) .ANG. .alpha. =
90.degree. .beta. = 110.212 (2).degree. .gamma. = 90.degree. Z (per
formula) 4 Density (g/cm.sup.3) 1.12 R 0.0785
[0075]
7TABLE 7 Crystallographic data of azithromycin form H. Form H
Empirical formula
C.sub.38H.sub.72N.sub.2O.sub.12.H.sub.2O.0.5C.sub.3H.sub.8O.sub.2
Crystal size (mm) 0.14 .times. 0.20 .times. 0.24 Formula weight
805.0 Space group P2.sub.1 monoclinic Unit cell dimensions a =
16.177 (1) .ANG. b = 16.241 (2) .ANG. c = 18.614 (1) .ANG. .alpha.
= 90.degree. .beta. = 108.34 (1).degree. .gamma. = 90.degree. Z
(per formula) 4 Density (g/cm.sup.3) 1.15 R 0.0687
[0076]
8TABLE 8 Crystallographic data of azithromycin form J. Form J
Formula C.sub.38H.sub.72N.sub.2O.sub.1-
2.H.sub.2O.0.5C.sub.3H.sub.8O Formula weight 796.0 Crystal size
(mm) 0.40 .times. 0.36 .times. 0.20 Space group P2.sub.1 monoclinic
Unit cell dimensions a = 16.191 (6) .ANG. b = 16.237 (10) .ANG. c =
18.595 (14) .ANG. .alpha. = 90.degree. .beta. = 108.92 (4).degree.
.gamma. = 90.degree. Z (per formula) 4 Density (g/cm.sup.3) 1.14 R
0.0789
[0077]
9TABLE 8A Crystallographic data of azithromycin form O. Form O
Formula C.sub.38H.sub.72N.sub.2O.-
sub.12.0.5H.sub.2O.0.5C.sub.4H.sub.10O Formula weight 795.04
Crystal size (mm) 0.40 .times. 0.36 .times. 0.20 Space group
P2.sub.1 monoclinic Unit cell dimensions a = 16.3602 (11) .ANG. b =
16.2042 (11) .ANG. c = 18.5459 (12) .ANG. .alpha. = 90.degree.
.beta. = 109.66 (10).degree. .gamma. = 90.degree. Z (per formula) 4
Density (g/cm.sup.3) 1.14 R 0.0421
[0078] Among these sixteen crystal forms, two isomorphic families
are identified. Family I includes forms F, G, H, J, M, N, O, and P.
Family II includes forms C, D, E and R. Form Q is distinct from
families I and II. The forms within a family are isomorphs that
crystallize in the same space group with slight variation of cell
parameters and comprise chemically related structures but different
elemental composition. In this case, the variation in chemical
composition among the isomorphs arises from incorporation of
different water/solvent molecules. Consequently, the isomorphs
display similar but non-identical X-ray diffraction patterns and
solid-state NMR spectra (ssNMR). Other techniques such as near
infrared spectroscopy (NIR), differential scanning calorimetry
(DSC), gas chromatography (GC), thermalgravimetric analysis (TGA),
or thermalgravimetric analysis/infrared spectroscopy analysis
(TG-IR), Karl Fischer water analysis (KF) and molecular
modeling/visualization provide data for affirmative identification
of isomorphs. Dehydration/desolvation temperatures were determined
by DSC with a heating rate of 5.degree. C./min
[0079] Form C: This crystal form was identified from a single
crystal structure (Table 2)--a monohydrate of azithromycin. It has
the space group of P2.sub.12.sub.12.sub.1 and similar cell
parameters as that of forms D and E; therefore, it belongs to
Family II isomorphs. Its calculated powder pattern is similar to
that of forms D and E.
[0080] Form D: Form D was crystallized from cyclohexane. The single
crystal structure of form D shows a stoichiometry of a
monohydrate/monocyclohexane solvate of azithromycin (Table 3).
Cyclohexane molecules were found to be disordered in the crystal
lattice. From single crystal data, the calculated water and
cyclohexane content of form D is 2.1 and 9.9%, respectively. Both
the powder pattern and the calculated powder pattern of form D are
similar to those of forms C and E. The powder samples of form D
showed a desolvation/dehydration endotherm with an onset
temperature of about 87.degree. C. and a broad endotherm between
200-280.degree. C. (decomposition) in DSC analysis at 50C/min from
30-300.degree. C.
[0081] Form D is prepared by slurrying azithromycin in cyclohexane
for 2-4 days. The solid form D azithromycin is collected by
filtration and dried.
[0082] Form E: Form E was obtained as a single crystal collected in
a THF/water medium. It is a monohydrate and mono-THF solvate by
single crystal analysis (Table 4). By its single crystal structure,
the calculated PXRD pattern is similar to that of form C and form D
making it a family II isomorph.
[0083] Form E is prepared by dissolving azithromycin in THF
(tetrahydrofuran). Diffusing water vapor through saturated
azithromycin THF solution over time yields crystals of Form E.
[0084] Form F: The single crystal of form F crystallized in a
monoclinic space group, P2.sub.1, with the asymmetric unit
containing two azithromycin, two waters, and one ethanol, as a
monohydrate/hemi-ethanola- te (Table 5). It is isomorphic to all
family I azithromycin crystalline forms. The calculated PXRD
pattern of this form is similar to those of other family I
isomorphs. The theoretical water and ethanol contents are 2.3 and
2.9%, respectively. The powder samples show a
dehydration/desolvation endotherm at an onset temperature between
110-125.degree. C. Form F is prepared by dissolving azithromycin in
ethanol (1-3 volumes by weight) at a temperature of about
50-70.degree. C. Upon complete dissolution, the solution is cooled
to subambient temperature to cause precipitation. The volume of
ethanol can be reduced by vacuum distillation with stirring for 1-2
hours to increase the yield. Alternatively, water (optionally
chilled to 0-20.degree. C.) about 0.1-2 volume can be added with
collection of solids within 30 minute after water addition. Cooling
the ethanol solution of azithromycin prior to the addition of water
to below below 20.degree. C., preferably below 15.degree. C., more
preferably below 10, and most preferably 5.degree. C. results in
substantially pure azithromycin form F. The solid form F
azithromycin is collected by filtration and dried.
[0085] Form G: The single crystal structure of form G consists of
two azithromycin molecules and three water molecules per asymmetric
unit (Table 6). This corresponds to a sesquihydrate with a
theoretical water content of 3.5%. The water content of powder
samples of form G ranges from about 2.5 to about 6%. The total
residual organic solvent is less than 1% of the corresponding
solvent used for crystallization, which is well below
stoichiometric quantities of solvate. This form dehydrates with an
onset temperature of about 110-120.degree. C.
[0086] Form G may be prepared by adding azithromycin to a premixed
organic solvent/water mixture (1/1 by volume), where the organic
solvent can be methanol, acetone, acetonitrile, ethanol or
isopropanol. The mixture is stirred and heated to an elevated
temperature, e.g. 45-55.degree. C. for 4-6 hours to cause
dissolution. Precipitation occurs during cooling to ambient
temperature. The solid form G azithromycin is collected by
filtration and dried.
[0087] Form H: This crystal form is a monohydrate/hemi-propylene
glycol solvate of azithromycin free base (Table 7). It was isolated
from a formulation solution containing propylene glycol. The
crystal structure of form H is isomorphic to crystal forms of
Family I.
[0088] Azithromycin form H is prepared by dissolving azithromycin
dihydrate in 6 volumes of propylene glycol. To the resulting
propylene glycol solution of azithromycin, 2 volumes of water is
added and precipitation occurrs. The slurry is stirred for 24 hours
and the solids are filtered and air-dried at ambient temperature to
afford crystalline Form H.
[0089] Form J: Form J is a monohydrate/hemi n-propanol solvate
(Table 8). The calculated solvent content is about 3.8% n-propanol
and about 2.3% water. The experimental data shows from about 2.5 to
about 4.0% n-propanol and from about 2.5 to about 3% water content
for powder samples. Its PXRD pattern is very similar to those of
its isomorphs F, G, H, M and N. Like F and G, the powder samples
have a dehydration/desolvation endotherm at 115-125.degree. C.
[0090] Form J is prepared by dissolving azithromycin in 4 volumes
of n-propanol at a temperature of about 25-55.degree. C. Water,
about 6-7 volumes, is added at room temperature and the slurry is
continuously stirred for 0.5-2 hours. The solid form J azithromycin
is collected by filtration and dried.
[0091] Form K: The PXRD pattern of form K was found in a mixture of
azithromycin form A and microcrystalline wax after annealing at
95.degree. C. for 3 hours. It is a lower hydrate of form A and is a
metastable high temperature form.
[0092] Form L: This form has only been observed upon heating the
dihydrate; form A. In variable temperature powder X-ray diffraction
(VT-PXRD) experiments, a new powder X-ray diffraction pattern
appears when form A is heated to about 90.degree. C. The new form,
designated form L, is a lower hydrate of form A because form A
loses about 2.5 weight % at 90.degree. C. by TGA, thus
corresponding to a conversion to a monohydrate. When cooled to
ambient temperature, form L rapidly reverts to form A.
[0093] Form M: Isolated from an isopropanol/water slurry, form M
incorporates both water and isopropanol. Its PXRD pattern and
ss-NMR spectrum are very similar to those of Family I isomorphs,
indicating that it belongs to Family I. By analogy to the known
crystal structures of Family I isomorphs, the single crystal
structure of form M would be a monohydrate/hemi-isopropranolate.
The dehydration/desolvation temperature of form M is about
115-125.degree. C.
[0094] Form M may be prepared by dissolving azithromycin in 2-3
volumes of isopropanol (IPA) at 40-50.degree. C. The solution is
cooled to below 15.degree. C., preferably below 10.degree. C., more
preferably about 5.degree. C. and 2-4 volumes of cold water about
5.degree. C. are added to effect precipitation. Seeds of form M
crystals may be added at the onset of crystallization. The slurry
is stirred less than about 5 hours, preferably less than about 3
hours, more preferably less than about 1 hour and most preferably
about 30 minutes or less and the solids, are collected by
filtration. The solids may be reslurried in isopropanol. This
procedure provides form M substantially in the absence of
azithromycin dihydrate.
[0095] Form N: Isolated from water/ethanol/isopropanol slurry of
form A, form N crystals may contain variable amounts of the
crystallization solvents and water. Its water content varies from
about 3.4 to about 5.3 weight percent. Analysis by GC Headspace
reveals a variable solvent content of ethanol and isopropanol. The
total solvent content of form N samples is usually lower than about
5% depending on the conditions of preparation and drying. The PXRD
pattern of form N is similar to that of forms F, G, H, J and M of
the Family I isomorphs. The dehydration/desolvation endotherm(s) of
the samples of form N may be broader and may vary between
110-130.degree. C.
[0096] Form N azithromycin may be prepared by recrystallizing
azithromycin from a mixture of azithromycin crystal
latice-incorporating organic solvents and water, such as ethanol,
isopropanol, n-propanol, acetone, acetonitirile etc. The solvent
mixture is heated to 45-60.degree. C. and azithromycin is added to
the heated solvent mixture, up to a total of about 4 volumes. Upon
dissolution, 1-3 volumes of water are added with continuous
agitation at 45-60.degree. C. Form N azithromycin precipitates as a
white solid. The slurry is allowed to cool to ambient temperature
with stirring. Solid form N azithromycin is isolated by filtration
and dried.
[0097] Form O: This crystal form is a hemihydrate hemi-n-butanol
solvate of azithromycin free base by single crystal structural data
(Table 8A). It was isolated from n-butanol solution of azithromycin
with diffusion of antisolvent. The crystal structure of form 0 is
isomorphic to crystal forms of Family I.
[0098] Azithromycin is completely dissolved in n-butanol. Addition
of an antisolvent, such as hexane, water, IPE or other non-solvent,
by diffusion results in precipitation of Form 0.
[0099] Form P: This is a proposed crystal form, being a hemihydrate
hemi-n-pentanol solvate of azithromycin free base. It can be
isolated from an n-pentanol solution of azithromycin with diffusion
of an antisolvent. The crystal structure of form P is isomorphic to
crystal forms of Family I.
[0100] Form P of azithromycin may be prepared as following:
Azithromycin is completely dissolved in n-pentanol; addition of an
antisolvent, such as hexane, water, isopropyl ether (IPE) or other
non-solvent, by diffusion results in precipitation of Form P.
[0101] Form Q: The crystal form of Q exhibits a unique powder X-ray
diffraction pattern. It contains about 4% water and about 4.5% THF,
being a hydrate hemi THF solvate. The main dehydration/desolvation
temperature is from about 80 to about 110.degree. C.
[0102] Azithromycin dihydrate is dissolved in 6 volumes of THF and
2 volumes of water are added. The solution is allowed to evaporate
to dryness at ambient conditions to afford crystalline Form Q.
[0103] Form R: This crystalline form is prepared by adding
amorphous azithromycin to 2.5 volumes of tert-butyl methyl ether
(MTBE). The resulting thick white suspension is stirred 3 days at
ambient conditions. Solids are collected by vacuum filtration and
air dried. The resulting bulk azithromycin form R has a theoretical
water content of 2.1 weight % and a theoretical methyl tert-butyl
ether content of 10.3 weight %.
[0104] Due to the similarity in their structures, isomorphs have
propensity to form a mixture of the forms within a family,
sometimes termed as `mixed crystals` or `crystalline solid
solution`. Form N is such a solid crystalline solution and was
found to be a mixture of Family I isomorphs by solvent composition
and solid-state NMR data.
[0105] Both Family I and Family II isomorphs are hydrates and/or
solvates of azithromycin. The solvent molecules in the cavities
have tendency to exchange between solvent and water under specific
conditions. Therefore, the solvent/water content of the isomorphs
may vary to a certain extent.
[0106] The crystal forms of isomorphic Family I are more stable
than form A when subjected to heating. Forms F, G, H, J, M and N
showed higher onset dehydration temperatures at 110-125.degree. C.
than that of form A with an onset dehydration temperature at about
90 to about 110.degree. C. and simultaneous solid-state conversion
to form L at about 90.degree. C.
[0107] Amorphous azithromycin: All crystal forms of azithromycin
contain water or solvent(s) or both water and solvent(s). When
water and solvent(s) are removed from the crystalline solids,
azithromycin becomes amorphous. Amorphous solids have advantages of
high initial dissolution rates.
[0108] The starting material for the synthesis of the various
crystal forms in the examples below was azithromycin dihydrate
unless otherwise noted. Other forms of azithromycin such as
amorphous azithromycin or other non-dihydrate crystalline forms of
azithromycin may be used.
EXAMPLES
Example
Preparation of Form D
[0109] Form D was prepared by slurrying azithromycin dihydrate in
cyclohexane for 2-4 days at an elevated temperature, e.g.
25-50.degree. C. The crystalline solids of form D were collected by
filtration and dried.
Example 2
Preparation of Form F
[0110] 2A: Azithromycin dihydrate was slowly added to one volume of
warm ethanol, about 70.degree. C., and stirred to complete
dissolution at 65 to 70.degree. C. The solution was allowed to cool
gradually to 2-5.degree. C. and one volume of chilled water was
added The crystalline solids were collected shortly (preferably
less than 30 minutes) after addition of water by vacuum
filtration.
[0111] 2B: Azithromycin dihydrate is slowly added to one volume of
warm ethanol, about 70.degree. C., and stirred to complete
dissolution at 65 to 70.degree. C. The solution is allowed to cool
gradually to 2-50C and ethanol volume may be reduced by vacuum
distillation. Seeds of Form F 1-2% wt may be introduced to
facilitate the crystallization. After stirring up to 2 hours the
crystalline solids are collected by vacuum filtration. The
isolation of the crystals yields substantially pure form F
azithromycin, form F azithromycin substantially free of form G
azithromycin and form F azithromycin substantially free of
azithromycin dihydrate.
Example 3
Preparation of Form G
[0112] A reaction vessel was charged with form A azithromycin. In a
separate vessel, 1.5 volumes methanol and 1.5 volumes water were
mixed. The solvent mixture was added to the reaction vessel
containing the form A azithromycin. The slurry was stirred with
heating to 50.degree. C. for approximately 5 hours. Heating was
discontinued and the slurry was allowed to cool with stirring to
ambient temperature. The form G azithromycin was collected by
filtration and allowed to air dry for approximately 30 minutes. The
collected form G azithromycin was further dried in a vacuum oven at
45.degree. C. This procedure yields substantially pure form G
azithromycin, and form G azithromycin substantially free of
azithromycin dihydrate.
Example 4
Preparation of Form J
[0113] Form J was prepared by dissolving azithromycin in 4 volumes
of n-propanol at a temperature of about 25.degree. C. Water (6.7
volumes) was added and the slurry is continuously stirred for 1
hour, followed by cooling to about 0.degree. C. The solid form J
azithromycin was collected by filtration and dried.
Example 5
Preparation of Form M Substantially in the Absence of Azithromycin
Dihydrate
[0114] 5A: Azithromycin dihydrate is completely dissolved in 2
volumes of warm isopropanol 40-50.degree. C. Seeds of Form M may be
optionally introduced to facilitate the crystallization. The
solution is then cooled to 0-5.degree. C. and 4 volumes of chilled
water as antisolvent are added and the solids are collected by
vacuum filtration. The solids are reslurried in 1 volume of
isopropanol for 3-5 hours at 40-45.degree. C. and then cooled to
0-5.degree. C. The crystalline solids are collected shortly (about
15 minutes) after addition of water by vacuum filtration. The
solids are reslurried in 0.5 to 1 volume of isopropanol at
25-40.degree. C. and cooled to about 50C followed by filtration to
collect solids of form M.
[0115] These procedures yield substantially pure form M
azithromycin, form M azithromycin substantially free of form G
azithromycin and form M azithromycin substantially free of
azithromycin dihydrate
Example 6
Preparation of Form N
[0116] Two volumes of ethanol and 2 volumes of isopropanol were
added to a reaction vessel and heated to 50.degree. C. Azithromycin
form A was added with stirring to the heated ethanol/isopropanol
mixture to yield a clear solution. The reaction vessel was charged
with 2 volumes distilled water (ambient temperature). Stirring was
continued at 50.degree. C. and solid form N azithromycin
precipitated after approximately 1 hr. Heating was discontinued 5
hours after the addition of the water. The slurry was allowed to
cool to ambient temperature. Precipitated form N azithromycin was
collected by filtration and dried for 4 hours in vacuum oven at
45.degree. C.
Example 7
Preparation of Amorphous Azithromycin
[0117] Crystalline form A azithromycin was heated to
110-120.degree. C. in an oven for overnight under vacuum. The
amorphous solids were collected and stored with desiccant as
needed.
Example 8
Preparation of Form H
[0118] Azithromycin dihydrate or other crystal forms was dissolved
in 6 volumes of propylene glycol. To the resulting propylene glycol
solution of azithromycin, 2 volumes of water were added and
precipitation occurred. The slurry was stirred for 24 hours and the
solids were filtered and air-dried at ambient temperature to afford
crystalline Form H.
Example 9
Preparation of Form Q
[0119] The crystalline powder was prepared by dissolving 500 mg
azithromycin Form A in 2 ml THF. To the clear, colorless solution
at room temperature was added 1 ml water. When the solution became
cloudy an additional 1 ml THF was added to dissolve the
azithromycin completely, and the solution was stirred at ambient
temperature. Solvent was allowed to evaporate over 7 days, after
which the dry solids were collected and characterized.
Example 10
Powder X-Ray Diffraction Analysis
[0120] Powder patterns were collected using a Bruker D5000
diffractometer (Madison, Wis.) equipped with copper radiation,
fixed slits (1.0, 1.0, 0.6 mm), and a Kevex solid state detector.
Data was collected from 3.0 to 40.0 degrees in 2 theta using a step
size of 0.04 degrees and a step time of 1.0 seconds. The results
are summarized in Table 9.
[0121] The experimental PXRD diffraction pattern of azithromycin
form A is given in FIG. 2.
[0122] The experimental PXRD diffraction pattern of azithromycin
form D is given in FIG. 6.
[0123] The experimental PXRD diffraction pattern of azithromycin
form F is given in FIG. 10.
[0124] The experimental PXRD diffraction pattern of azithromycin
form G is given in FIG. 13.
[0125] The experimental PXRD diffraction pattern of azithromycin
form J is given in FIG. 16.
[0126] The experimental PXRD diffraction pattern of azithromycin
form M is given in FIG. 18.
[0127] The experimental PXRD diffraction pattern of azithromycin
form N is given in FIG. 19.
[0128] The experimental PXRD diffraction pattern of amorphous
azithromycin is given in FIG. 20.
[0129] The experimental PXRD diffraction pattern of azithromycin
form Q is given in FIG. 30.
[0130] The experimental PXRD diffraction pattern of azithromycin
form R is given in FIG. 31.
[0131] The experimental variability from sample to sample is about
.+-.0.20 in 2 theta, and the same variations were observed between
the calculated powder from single crystal structure and
experimental data. Detailed analysis showed that the isomorphs in
Family I can be discerned by PXRD with sets of characteristic peaks
given in Table 9.
10TABLE 9 Azithromycin Powder X-ray Diffraction Peaks in 2-theta
.+-.0.2.degree. A D F G J M N Q 7.2 3.9 5.7 5.0 5.0 5.0 6.2 5.7 7.9
7.3 6.2 5.8 5.7 5.6 7.3 6.1 9.3 7.7 7.4 6.2 6.2 6.2 7.8 6.8 9.9
10.1 7.8 7.4 7.3 7.3 9.8 8.4 11.2 10.6 8.9 7.9 7.8 7.8 11.2 9.5
12.0 11.5 9.8 9.8 8.2 8.2 11.9 10.6 12.7 12.3 10.3 10.2 9.7 9.8
12.5 11.2 13.0 12.8 11.2 10.8 10.3 10.2 14.0 11.5 14.0 13.6 11.5
11.2 11.2 11.2 14.3 12.4 15.6 14.5 11.9 11.6 11.4 11.9 14.7 12.7
16.0 15.4 12.2 12.0 11.9 12.2 15.3 13.4 16.4 15.6 12.5 12.5 12.3
12.5 15.7 13.6 16.8 16.9 13.9 13.3 12.5 14.0 16.1 14.1 17.5 18.3
14.3 14.0 13.9 14.6 16.6 14.4 18.2 19.0 14.7 14.4 14.2 15.3 17.1
14.9 18.7 19.9 14.8 14.6 14.6 15.9 17.4 16.3 19.1 20.8 15.3 14.9
15.3 16.6 18.5 17.2 19.8 21.4 15.7 15.3 15.7 17.1 19.0 18.2 20.5
21.6 16.2 15.7 16.0 17.5 19.6 19.0 20.9 22.0 16.6 16.3 16.6 18.4
20.0 19.5 21.2 23.0 17.1 16.6 17.0 18.5 20.4 19.8 21.6 23.3 17.2
17.2 17.2 19.1 21.0 20.2 21.8 17.7 17.4 17.5 19.6 21.8 20.5 24.0
18.0 17.8 18.1 20.0 22.5 21.1 18.5 18.1 18.5 20.4 23.5 21.6 19.0
18.6 19.0 20.9 21.9 19.6 19.0 19.7 21.7 22.2 20.0 19.6 20.0 22.5
23.6 20.5 20.0 20.4 23.2 25.1 21.0 20.5 20.9 23.6 21.7 21.1 21.7
22.0 21.8 22.4 22.4 22.5 22.6 22.6 23.5 23.3 23.1 23.5 23.5
[0132] The peaks underlined are the characteristic peaks among
forms A, D, Family I and Q.
[0133] The peaks in italic and underlined are the sets of peaks
that are characteristic within Family I isomorphs.
[0134] Family I isomorphs have the following common
characteristics: the diffraction peaks at 6.2, 11.2, 21.0.+-.0.1
and 22.5.+-.0.1 degree in 2-theta. Each isomorph displays
representative sets of diffraction peaks given in the following,
and each set has characteristic spacing between the peaks.
[0135] The diffraction peak positions reported are accurate to
within .+-.0.2 degree of 2-theta.
[0136] A representative PXRD pattern of form A is shown in FIG. 2.
Form A displays peaks at 9.3, 13.0 and 18.7 degrees of 2-theta.
[0137] A representative PXRD pattern of form D is shown in FIG. 6.
Form D displays peaks at 3.9,10.1, 10.6 and 21.4 degrees of
2-theta.
[0138] A representative PXRD pattern of Form F is shown in FIG. 10.
Form F displays the characteristic peaks of Family I and three sets
of peaks, being set 1 at 2-theta of 11.2 and 11.5; set 2 at 2-theta
of 13.9, 14.3, 14.7 and 14.8; set 3 at 2-theta of 16.2, 16.6, 17.1,
17.2 and 17.7.
[0139] A representative PXRD pattern of Form G is shown in FIG. 13.
Form G displays the characteristic peaks of Family I and three sets
of peaks, being set 1 at 2-theta of 11.2 and 11.6 2; set at 2-theta
of 14.0, 14.4, 14.6 and 14.9; set 3 at 2-theta of 16.3, 16.6, 17.2,
17.4 and 17.8.
[0140] A representative PXRD pattern of Form J is shown in FIG. 16.
Form J displays the characteristic peaks of Family I and three sets
of peaks, being set 1 at 2-theta of 11.2 and 11.4; set 2 at 2-theta
of 13.9, 14.2 and 14.6; set 3 at 2-theta of 16.0, 16.6, 17.0, 17.2
and 17.5.
[0141] A representative PXRD pattern of Form M is shown in FIG. 18.
Form M displays the characteristic peaks of Family I and three sets
of peaks, being set 1 at 2-theta of 11.2; set 2 at 2-theta of 14.0
and 14.6; set 3 at 2-theta of 15.9, 16.6, 17.1 and 17.5.
[0142] A representative PXRD pattern of Form N is shown in FIG. 10.
Form N displays the characteristic peaks of Family I. The sets of
peaks of form N are similar to those of forms F, G, J and M, being
set 1 at 2-theta of 11.2 to 11.6; set 2 at 2-theta of 13.9 to 15.0;
and set 3 at 2-theta of 15.9 to 17.9, with the peaks may vary
slightly in position, intensity and width due to mixing of variable
proportion of isomorphs in Family I.
[0143] A representative PXRD pattern of form Q is shown in FIG. 30.
Form Q displays peaks at 2-theta of 6.8, 8.4 and 20.2 degree.
[0144] A representative PXRD pattern of form R is shown in FIG.
31.
Example 11
Single Crystal X-Ray Analysis
[0145] Data were collected at room temperature using Bruker X-ray
diffractometers equipped with copper radiation and graphite
monochromators. Structures were solved using direct methods. The
SHELXTL computer library provided by Bruker AXS, Inc facilitated
all necessary crystallographic computations and molecular displays
(SHELXTL Reference Manual, Version 5.1, Bruker AXS, Madison, Wis.,
USA (1997)).
Example 12
Calculation of PXRD Pattern from Single Crystal Data
[0146] To compare the results between a single crystal and a powder
sample, a calculated powder pattern can be obtained from single
crystal results. The XFOG and XPOW computer programs provided as
part of the SHELXTL computer library were used to perform this
calculation. Comparing the calculated powder pattern with the
experimental powder pattern confirms whether a powder sample
corresponds to an assigned single crystal structure (Table 9A).
This procedure was performed on the crystal forms of azithromycin
A, D, F, G, and J.
[0147] The calculated PXRD diffraction pattern of azithromycin form
A is given in FIG. 1.
[0148] The calculated PXRD diffraction pattern of azithromycin form
D is given in FIG. 5.
[0149] The calculated PXRD diffraction pattern of azithromycin form
F is given in FIG. 9.
[0150] The calculated PXRD diffraction pattern of azithromycin form
G is given in FIG. 12.
[0151] The calculated PXRD diffraction pattern of azithromycin form
J is given in FIG. 15.
[0152] The results are displayed in the overlaid powder X-ray
diffraction patterns for forms A, D, F, G, and J in FIGS. 3, 7, 11,
14 and 17, respectively. The lower pattern corresponds to the
calculated powder pattern (from single crystal results) and the
upper pattern corresponds to a representative experimental powder
pattern. A match between the two patterns indicated the agreement
between powder sample and the corresponding single crystal
structure.
[0153] Table 9A: Cacluated and Experimental PXRD Peaks of lsomorphs
of Family I
11 F calculated F experimental G calculated G experimental J
calculated J experimental M experimental 5.2 5.0 5.7 5.8 5.8 5.7
5.6 6.3 6.2 6.2 6.2 6.3 6.2 6.2 7.4 7.4 7.5 7.4 7.4 7.3 7.3 7.9 7.8
7.9 7.9 7.9 7.8 7.8 8.8 8.9 8.9 9.3 8.3 8.2 8.2 9.9 9.8 9.9 9.9 9.8
9.7 9.8 10.3 10.3 10.2 10.4 10.3 10.2 10.9 10.9 10.8 11.3 11.2 11.3
11.2 11.2 11.2 11.2 11.5 11.4 11.6 11.6 11.4 11.4 missing 12.0 11.9
12.0 11.9 12.0 11.9 11.9 12.3 12.2 12.3 12.3 12.3 12.2 12.6 12.5
12.5 12.5 12.6 12.5 12.5 14.0 14.0 13.4 13.3 14.0 13.9 14.0 14.3
14.3 14.1 14.0 14.2 14.2 missing 14.4 14.4 14.7 14.7 14.7 14.6 14.7
14.6 14.6 14.9 14.8 14.9 14.9 14.8 15.4 15.3 15.4 15.3 15.3 15.3
15.3 15.8 15.7 15.7 15.7 15.8 15.7 15.9 16.2 16.2 16.3 16.3 16.0
16.0 missing 16.6 16.6 16.6 16.6 16.7 16.6 16.6 17.1 17.2 17.1 17.1
17.0 17.1 17.3 17.3 17.3 17.2 17.4 17.2 missing 17.5 17.4 17.5 17.4
17.6 17.5 17.5 17.7 17.7 17.9 17.8 17.9 18.0 18.0 18.1 18.1 18.2
18.1 18.4 18.6 18.5 18.7 18.7 18.5 18.5 18.5 19.1 19.0 19.1 19.0
19.1 19.0 19.1 19.7 19.6 19.6 19.6 19.8 19.7 19.6 20.0 20.0 20.0
20.0 20.1 20.0 20.0 20.5 20.4 20.6 20.5 20.5 20.4 20.4 21.1 21.0
21.2 21.0 20.8 20.9 20.9 21.8 21.7 21.6 21.6 21.7 21.7 22.1 22.0
21.8 21.8 21.8 22.5 22.4 22.3 22.2 22.5 22.4 22.5 22.7 22.6 22.5
22.5 22.8 22.6 23.1 23.1 22.9 23.4 23.3 23.2 23.6 23.5 23.5 23.5
23.7 23.5 23.6
Example 13
Solid State NMR Analysis
[0154] Solid State NMR analysis:
[0155] All .sup.13C solid state NMR spectra were collected on an
11.75 T spectrometer (Bruker Biospin, Inc., Billerica, Mass.),
corresponding to 125 MHz .sup.13C frequency. The spectra were
collected using a cross-polarization magic angle spinning (CPMAS)
probe operating at ambient temperature and pressure. Depending on
the quantity of sample analyzed, 7 mm BL or 4 mm BL Bruker probes
were employed, accomodating 300 mg and 75 mg of sample with maximum
speeds of 7 kHz and 15 kHz, respectively. Data were processed with
an exponential line broadening function of 5.0 Hz. Proton
decoupling of 65 kHz and 100 kHz were used with the 7 mm and 4 mm
probes, respectively. A sufficient number of acquisitions were
averaged out to obtain adequate signal-to-noise ratios for all
peaks. Typically, 600 scans were acquired with recycle delay of 3.0
s (seconds), corresponding approximately to a 30 minute total
acquisition time. Magic angle was adjusted using KBr powder
according to standard NMR vendor practices. The spectra were
referenced relative to either the methyl resonace of
hexamethylbenzen (HMB) at 17.3 ppm or the upfield resonance of
adamantane (ADM) at 29.5 ppm. HMB referenced spectra show chemical
shifts of all peaks shifted down field by 0.08 ppm with respect to
same spectra referenced to ADM. The spectral window minimally
included the spectra region from 190 to 0 ppm. The results are
summarized in table 10. Ss-NMR spectra for forms M, H and R were
referenced to ADM. Ss-NMR spectra for forms A, D, G, F, J and N
were referenced to HMB. Forms H and R were spun at a rate of 15
kHz.
12TABLE 10 .sup.13C ss-NMR chemical shifts of Azithromycin (.+-.0.2
ppm) A D G F J M N H R 178.1 178.1 179.5* 179.5 179.6 179.6 179.6
179.5 177.9 104.1 103.9 105.5 178.6 178.4 105.6 178.7 178.7 104.6
98.4 95.1 103.5 105.5 105.5 103.4 105.6 105.4 103.6 84.6 84.2 95.0
103.4 103.4 94.9 103.6 103.2 95.3 82.6 79.4 86.2 94.9 95.0 86.7
95.0 95.0 85.4 79.3 78.9 83.1 86.4 86.4 82.9 86.5 86.4 84.0 78.3
75.7 78.9 83.0 82.9 79.3 83.1 82.7 79.4 75.6 74.6 78.2 79.1 79.2
78.1 79.0 79.2 79.0 74.7 74.0 77.6 78.1 78.1 77.0 77.9 78.3 75.6
73.9 72.9 76.4 77.9 76.8 76.7 76.5 78.0 74.5 73.5 71.9 75.7 76.5
76.2 74.7 74.8 76.4 73.9 70.8 71.0 74.7 74.7 74.7 74.2 74.2 74.7
73.9 68.0 69.4 74.3 74.1 74.1** 71.3 73.6 74.1 72.9 66.2 67.8 73.5
73.5 72.0 69.2 71.5 73.5 71.8 63.8 65.7 71.3 71.4 71.3 68.6 69.2
73.1 71.0 63.2 64.7 69.1 69.1 69.2 67.3 68.7 71.2 69.1 52.2 49.2
68.8 68.6 68.6 66.2 67.3 69.1 67.5 44.3 45.8 67.4 67.3 67.3** 65.5
66.2 68.4 65.6 42.6 43.1 65.9 66.1 66.2** 63.8 65.7 67.3 64.5 41.7
40.6 65.2 65.6 65.5** 63.3 63.7 66.9 49.4 39.1 37.1 64.0 63.6 63.7
50.0 58.1 66.1 45.7 35.4 36.4 63.3 58.0 50.0 47.1 50.1 65.5* 42.9
34.6 29.6 50.0 50.0 46.9 45.9 47.1 63.7* 41.6 26.9 29.3 46.9 47.0
45.9 44.7 46.0 49.9 40.4 26.3 28.0 46.0 45.9 44.7 43.8 44.8 46.8
37.0 23.7 27.7 44.5 44.7 43.7 41.9 43.8 45.9 36.2 23.3 22.1 43.7
43.7 41.6 41.1 41.5 44.5 29.4 21.7 21.1 41.5 41.5 41.0 37.4 41.1
43.8* 29.0 19.5 18.6 40.8 41.1 37.1 36.2 37.3 41.7 28.2 17.5 16.7
37.5 37.3 36.5** 33.6 36.5 40.9 27.4 15.9 16.1 36.5 36.4 35.4**
30.1 33.7 37.1 21.4 13.2 10.6 33.6 33.6 33.5 28.1 30.4 36.3 20.8
11.3 9.0 30.0 30.3 30.4 27.2 28.1 33.7 18.7 7.2 8.6 27.9 28.0 28.0
26.0 27.2 33.3 16.5 27.3 27.1 27.1 23.2 26.0 30.5* 16.1 23.1 23.2
25.2 22.8 23.2 27.9 15.7 22.5 22.6 23.2 22.5 22.6 27.1 10.3 21.9
21.9 22.5** 21.8 22.0 23.1 9.6
[0156] The chemical shifts labeled in bold and underlined are the
peaks or sets of peaks representative of each form. The chemical
shifts labeled in italic are the solvent peaks that may be broad
and variable (.+-.0.4 ppm). The chemical shifts labeled with single
asterisk may show splitting of <0.3 ppm. The chemical shifts
labeled with double asterisks may show variation of .+-.0.3 ppm
13TABLE 10 (continued). .sup.13C ss-NMR chemical shifts of
Azithromycin (.+-.0.2 ppm) A D G F J M N H R 20.9 20.8 21.9** 20.2
20.8 22.6 8.9 20.2 20.4 20.7 18.9 19.0 22.3 8.6 18.8 18.9 18.9 17.4
16.9 21.9 17.0 16.8 16.8 16.3 15.8 20.7 16.0 17.2 15.6** 15.5 12.2
20.3 12.2 15.7 12.1 12.1 9.9 18.8 10.4 12.2 11.5 10.3 9.4 17.1 9.9
10.1 12.1 9.6 7.9 16.6 9.3 9.8 10.0 9.3 6.6 15.8 7.6 9.3 9.3 7.7
15.4 6.5 7.9 8.1 7.1 12.0 6.6 6.8** 9.9 9.1 7.9 7.0
[0157] The chemical shifts labeled in bold and underlined are the
peaks or sets of peaks representative of each form. The chemical
shifts labeled in italic are the solvent peaks that may be broad
and variable (.+-.0.4 ppm). The chemical shifts labeled with single
asterisk may show splitting of <0.3 ppm. The chemical shifts
labeled with double asterisks may show variation of .+-.0.3 ppm
[0158] The chemical shifts reported are accurate to within .+-.0.2
ppm unless otherwise indicated.
[0159] A representative .sup.13C ssNMR spectrum of form A is shown
in FIG. 21. Form A displays a peak at 178.1 ppm, and peaks at
104.1, 98.4, 84.6, 26.9, 13.2, 11.3 and 7.2 ppm.
[0160] A representative .sup.13C ssNMR spectrum of form D is shown
in FIG. 22. Form D displays the highest chemical shift peak of
178.1 ppm and peaks at chemical shifts of 103.9, 95.1, 84.2, 10.6,
9.0 and 8.6 ppm.
[0161] A representative .sup.13C ssNMR spectrum of form F is shown
in FIG. 23. Form F has two chemical shift peaks at approximately
179.1.+-.2 ppm, being 179.5 ppm and 178.6 ppm, and a set of 5 peaks
at 10.1, 9.8, 9.3, 7.9, and 6.6 ppm, and ethanol peaks at
58.0.+-.0.5 ppm and 17.2.+-.0.5 ppm. The solvent peaks can be broad
and relatively weak in intensity.
[0162] A representative .sup.13C ssNMR spectrum of form G is shown
in FIG. 24. Form G has the highest chemical shift peak of 179.5
ppm, being a single peak with possible splitting of <0.3 ppm and
a set of 5 peaks at 10.4, 9.9, 9.3, 7.6, 6.5 ppm.
[0163] A representative .sup.13C ssNMR spectrum of form J is shown
in FIG. 25. Form J has two chemical shift peaks at approximately
179.1.+-.2 ppm those being 179.6 ppm and 784.4 ppm, a set of 4
peaks at 10.0, 9.3, 8.1 and 6.8 ppm and n-propanol peaks at
11.5.+-.0.5 ppm and 25.2.+-.0.5 ppm. The solvent peak can be broad
and relatively weak in intensity.
[0164] A representative .sup.13C ssNMR spectrum of form M is shown
in FIG. 26. Form M has one chemical shift peak at 179.+-.1 ppm,
being 179.6 ppm, peaks at 41.9, and 16.3 ppm, a set of 5 peaks at
10.3, 9.6, 9.3, 7.7 and 7.1 ppm and an isopropanol peak at
26.0.+-.0.5 ppm. The solvent peak can be broad and relatively weak
in intensity.
[0165] A representative .sup.13C ssNMR spectrum of form N is shown
in FIG. 27. Form N displays chemical shifts as a combination of
isomorphs in Family I. The peaks may vary in chemical shift and in
relative intensities and width due to the mixing of variable
proportion of isomorphs contained in the form N crystalline solid
solution.
[0166] A representative .sup.13C ssNMR spectrum of amorphous form
is shown in FIG. 28. The amorphous azithromycin displays broad
chemical shifts. The characteristic chemical shifts have the peak
positions at 179 and 11.+-.0.5 ppm.
[0167] A summary of the observed ssNMR peaks for forms A, D, F, G,
H, J, M, N and R azithromycin is given in Table 10.
Example 14
NMR Analysis of a Dosage Form
[0168] To demonstrate the ability of .sup.13C ssNMR to identify the
form of azithromycin contained in a pharmaceutical dosage form,
coated azithromycin tablets containing form G azithromycin were
prepared and analyzed by .sup.13C ssNMR. Tablets were wet
granulated and tabletted on an F-Press (Manesty, Liverpool, UK)
using 0.262".times.0.531" tooling. Tablets were formulated and
tabletted to contain 250 mg of form G azithromycin with a total
tablet weight of 450 mg using the formula given below. The tablets
were uniformly coated with pink Opadry II.RTM. (mixture of lactose
monohydrate, hydroxypropylmethylcellulose, titanium dioxide, Drug
& Cosmetic red # 30, and triacetin) (Colorcon, West Point,
Pa.).
14 Material Percentage Batch(g) Azithromycin form "G" 58.23 174.69
Pregellatinized corn starch 6.00 18.00 Anhydrous dicalcium
phosphate 30.85 92.55 Sodium croscarmelose 2.00 6.00 Magnesium
stearate with 10% sodium 2.92 8.76 laurel sulfate Total 100.00
300.00
[0169] A coated tablet was gently crushed and the powdered sample
was packed with a packing tool in solid state rotor containing no
.sup.13C background. Analysis of the sample was performed under
conditions outlined in Example 13.
[0170] A representative .sup.13C ssNMR spectrum of the tablet
containing form G azithromycin is given in FIG. 29.
Example 15
Antimicrobial Activity
[0171] The activity of the crystal forms of the present invention
against bacterial and protozoa pathogens is demonstrated by the
compound's ability to inhibit growth of defined strains of human
(Assay I) or animal (Assays II and III) pathogens.
Assay I
[0172] Assay I, described below, employs conventional methodology
and interpretation criteria and is designed to provide direction
for chemical modifications that may lead to compounds that
circumvent defined mechanisms of macrolide resistance. In Assay I,
a panel of bacterial strains is assembled to include a variety of
target pathogenic species, including representatives of macrolide
resistance mechanisms that have been characterized. Use of this
panel enables the chemical structure/activity relationship to be
determined with respect to potency, spectrum of activity, and
structural elements or modifications that may be necessary to
obviate resistance mechanisms. Bacterial pathogens that comprise
the screening panel are shown in the table below. In many cases,
both the macrolide-susceptible parent strain and the
macrolide-resistant strain derived from it are available to provide
a more accurate assessment of the compound's ability to circumvent
the resistance mechanism. Strains that contain the gene with the
designation of ermA/ermB/ermC are resistant to macrolides,
lincosamides, and streptogramin B antibiotics due to modifications
(methylation) of 23S rRNA molecules by an Erm methylase, thereby
generally prevent the binding of all three structural classes. Two
types of macrolide efflux have been described; msrA encodes a
component of an efflux system in staphylococci that prevents the
entry of macrolides and streptogramins while mefAlE encodes a
transmembrane protein that appears to efflux only macrolides.
Inactivation of macrolide antibiotics can occur and can be mediated
by either a phosphorylation of the 2'-hydroxyl (mph) or by cleavage
of the macrocyclic lactone (esterase). The strains may be
characterized using conventional polymerase chain reaction (PCR)
technology and/or by sequencing the resistance determinant. The use
of PCR technology in this application is described in J. Sutcliffe
et al., "Detection Of Erythromycin-Resistant Determinants By PCR",
Antimicrobial Agents and Chemotherapy, 40(11), 2562-2566 (1996).
The assay is performed in microtiter trays and interpreted
according to Performance Standards for Antimicrobial Disk
Susceptibility Tests--Sixth Edition: Approved Standard, published
by The National Committee for Clinical Laboratory Standards (NCCLS)
guidelines; the minimum inhibitory concentration (MIC) is used to
compare strains. The crystalline compound is initially dissolved in
dimethylsulfoxide (DMSO) as 40 mg/ml stock solution.
15 Strain Designation Macrolide Resistance Mechanism(s)
Staphylococcus aureus 1116 susceptible parent Staphylococcus aureus
1117 ErmB Staphylococcus aureus 0052 susceptible parent
Staphylococcus aureus 1120 ErmC Staphylococcus aureus 1032 msrA,
mph, esterase Staphylococcus hemolyticus 1006 msrA, mph
Streptococcus pyogenes 0203 susceptible parent Streptococcus
pyogenes 1079 ErmB Streptococcus pyogenes 1062 susceptible parent
Streptococcus pyogenes 1061 ErmB Streptococcus pyogenes 1064 ErmB
Streptococcus agalactiae 1024 susceptible parent Streptococcus
agalactiae 1023 ErmB Streptococcus pneumoniae 1016 Susceptible
Streptococcus pneumoniae 1046 ErmB Streptococcus pneumoniae 1095
ErmB Streptococcus pneumoniae 1175 MefE Streptococcus pneumoniae
0085 Susceptible Haemophilus influenzae 0131 Susceptible Moraxella
catarrhalis 0040 Susceptible Moraxella catarrhalis 1055
erythromycin intermediate resistance Escherichia coli 0266
Susceptible
[0173] Assay II is utilized to test for activity against
Pasteurella multocida and Assay III is utilized to test for
activity against Pasteurella haemolytica.
Assay II
[0174] This assay is based on the liquid dilution method in
microliter format. A single colony of P. multocida (strain 59A067)
is inoculated into 5 ml of brain heart infusion (BHI) broth. The
test compound is prepared by solubilizing 1 mg of the compound in
125 .mu.l of dimethylsulfoxide (DMSO). Dilutions of the test
compound are prepared using uninoculated BHI broth. The
concentrations of the test compound used range from 200 gg/ml to
0.098 .mu.g/ml by two-fold serial dilutions. The P. multocida
inoculated BHI is diluted with uninoculated BHI broth to make a
10.sup.4 cell suspension per 200 .mu.l. The BHI cell suspensions
are mixed with respective serial dilutions of the test compound,
and incubated at 37.degree. C. for 18 hours. The minimum inhibitory
concentration (MIC) is equal to the concentration of the compound
exhibiting 100% inhibition of growth of P. multocida as determined
by comparison with an uninoculated control.
Assay III
[0175] This assay is based on the agar dilution method using a
Steers Replicator. Two to five colonies isolated from an agar plate
are inoculated into BHI broth and incubated overnight at 37.degree.
C. with shaking (200 rpm). The next morning, 300 .mu.l of the fully
grown P. haemolytica preculture is inoculated into 3 ml of fresh
BHI broth and is incubated at 37.degree. C. with shaking (200 rpm).
The appropriate amounts of the test compounds are dissolved in
ethanol and a series of two-fold serial dilutions are prepared. Two
ml of the respective serial dilution is mixed with 18 ml of molten
BHI agar and solidified. When the inoculated P. haemolytica culture
reaches 0.5 McFarland standard density, about 5 .mu.l of the P.
haemolytica culture is inoculated onto BHI agar plates containing
the various concentrations of the test compound using a Steers
Replicator and incubated for 18 hours at 37.degree. C. Initial
concentrations of the test compound range from 100-200 .mu.g/ml.
The MIC is equal to the concentration of the test compound
exhibiting 100% inhibition of growth of P. haemolytica as
determined by comparison with an uninoculated control.
[0176] The in vivo activity of the crystal forms of the present
invention can be determined by conventional animal protection
studies well known to those skilled in the art, usually carried out
in mice.
[0177] Mice are allotted to cages (10 per cage) upon their arrival,
and allowed to acclimate for a minimum of 48 hours before being
used. Animals are inoculated with 0.5 ml of a 3.times.10.sup.3
CFU/ml bacterial suspension (P. multocida strain 59A006)
intraperitoneally. Each experiment has at least 3 non-medicated
control groups including one infected with 0.1.times. challenge
dose and two infected with 1.times. challenge dose; a 10.times.
challenge data group may also be used. Generally, all mice in a
given study can be challenged within 30-90 minutes, especially if a
repeating syringe (such as a Cornwall.RTM. syringe) is used to
administer the challenge. Thirty minutes after challenging has
begun, the first compound treatment is given. It may be necessary
for a second person to begin compound dosing if all of the animals
have not been challenged at the end of 30 minutes. The routes of
administration are subcutaneous or oral doses. Subcutaneous doses
are administered into the loose skin in the back of the neck
whereas oral doses are given by means of a feeding needle. In both
cases, a volume of 0.2 ml is used per mouse. Compounds are
administered 30 minutes, 4 hours, and 24 hours after challenge. A
control compound of known efficacy administered by the same route
is included in each test. Animals are observed daily, and the
number of survivors in each group is recorded. The P. multocida
model monitoring continues for 96 hours (four days) post
challenge.
[0178] The PD.sub.50 is a calculated dose at which the compound
tested protects 50% of a group of mice from mortality due to the
bacterial infection that would be lethal in the absence of drug
treatment.
[0179] The crystal forms of the present invention (hereinafter "the
active compound(s)"), may be administered through oral, parenteral,
topical, or rectal routes in the treatment or prevention of
bacterial or protozoa infections. In general, the active compound
is most desirably administered in dosages ranging from about 0.2 mg
per kg body weight per day (mg/kg/day) to about 200 mg/kg/day in
single or divided doses (i.e., from 1 to 4 doses per day), although
variations will necessarily occur depending upon the species,
weight and condition of the subject being treated and the
particular route of administration chosen. However, a dosage level
that is in the range of about 2 mg/kg/day to about 50 mg/kg/day is
most desirably employed. Variations may nevertheless occur
depending upon the species of mammal, fish or bird being treated
and its individual response to said medicament, as well as on the
type of pharmaceutical formulation chosen and the time period and
interval at which such administration is carried out. In some
instances, dosage levels below the lower limit of the aforesaid
range may be more than adequate, while in other cases still larger
doses may be employed without causing any harmful side effects,
provided that such larger doses are first divided into several
small doses for administration throughout the day.
[0180] The active compound may be administered alone or in
combination with pharmaceutically acceptable carriers or diluents
by the routes previously indicated, and such administration may be
carried out in single or multiple doses. More particularly, the
active compound may be administered in a wide variety of different
dosage forms, i.e., they may be combined with various
pharmaceutically acceptable inert carriers in the form of tablets,
capsules, lozenges, troches, hard candies, powders, sprays, creams,
salves, suppositories, jellies, gels, pastes, lotions, ointments,
sachets, powders for oral suspension, aqueous suspensions,
injectable solutions, elixirs, syrups, and the like. Such carriers
include solid diluents or fillers, sterile aqueous media and
various non-toxic organic solvents, etc. Moreover, oral
pharmaceutical compositions can be suitably sweetened and/or
flavored. In general, the active compound is present in such dosage
forms at concentration levels ranging from about 1.0% to about 70%
by weight.
[0181] For oral administration, tablets containing various
excipients such as microcrystalline cellulose, sodium citrate,
calcium carbonate, dicalcium phosphate and glycine may be employed
along with various disintegrants such as starch (and preferably
corn, potato or tapioca starch), alginic acid and certain complex
silicates, together with granulation binders like
polyvinylpyrrolidone, sucrose, gelatin and acacia. Additionally,
lubricating agents such as magnesium stearate, sodium lauryl
sulfate and talc are often very useful for tabletting purposes.
Solid compositions of a similar type may also be employed as
fillers in gelatin capsules; preferred materials in this connection
also include lactose or milk sugar as well as high molecular weight
polyethylene glycols. When aqueous suspensions and/or elixirs are
desired for oral administration, the active compound may be
combined with various sweetening or flavoring agents, coloring
matter or dyes, and, if so desired, emulsifying and/or suspending
agents as well, together with such diluents as water, ethanol,
propylene glycol, glycerin and various like combinations
thereof.
[0182] For parenteral administration, solutions of the active
compound in either sesame or peanut oil or in aqueous propylene
glycol may be employed. The aqueous solutions should be suitably
buffered (preferably pH greater than 8) if necessary and the liquid
diluent first rendered isotonic. These aqueous solutions are
suitable for intravenous injection purposes. The oily solutions are
suitable for intraarticular, intramuscular and subcutaneous
injection purposes. The preparation of all these solutions under
sterile conditions is readily accomplished by standard
pharmaceutical techniques will known to those skilled in the
art.
[0183] Additionally, it is also possible to administer the active
compound topically and this may be done by way of creams, jellies,
gels, pastes, patches, ointments and the like, in accordance with
standard pharmaceutical practice.
[0184] For administration to animals other than humans, such as
cattle or domestic animals, the active compounds may be
administered in the feed of the animals or orally as a drench
composition.
[0185] The active compound may also be administered in the form of
liposome delivery systems, such as small unilamellar vesicles,
large unilamellar vesicles and multilamellar vesicles. Liposomes
can be formed from a variety of phospholipids, such as cholesterol,
stearylamine or phosphatidylcholines.
* * * * *