U.S. patent application number 10/502902 was filed with the patent office on 2005-07-28 for pharmaceutical formulation comprising an aqueous suspension of an androstane derivative for the treatment of inflammatory and allergic conditions.
Invention is credited to Biggadike, Keith, Buxton, Ian, Coote, Steven John, Nice, Rosalyn Kay, Reed, Kenton Lewis, Sayani, Amyn, Sharma, Avinash Chander.
Application Number | 20050164996 10/502902 |
Document ID | / |
Family ID | 27732225 |
Filed Date | 2005-07-28 |
United States Patent
Application |
20050164996 |
Kind Code |
A1 |
Biggadike, Keith ; et
al. |
July 28, 2005 |
Pharmaceutical formulation comprising an aqueous suspension of an
androstane derivative for the treatment of inflammatory and
allergic conditions
Abstract
There is provided a pharmaceutical formulation comprising an
aqueous suspension of particulate compound of formula (I) 1 or a
solvate thereof.
Inventors: |
Biggadike, Keith;
(Hertfordshire, GB) ; Buxton, Ian; (Ontario,
CA) ; Coote, Steven John; (Hertfordshire, GB)
; Nice, Rosalyn Kay; (Hertfordshire, GB) ; Reed,
Kenton Lewis; (Ontario, CA) ; Sayani, Amyn;
(Ontario, CA) ; Sharma, Avinash Chander; (Ontario,
CA) |
Correspondence
Address: |
DAVID J LEVY, CORPORATE INTELLECTUAL PROPERTY
GLAXOSMITHKLINE
FIVE MOORE DR., PO BOX 13398
RESEARCH TRIANGLE PARK
NC
27709-3398
US
|
Family ID: |
27732225 |
Appl. No.: |
10/502902 |
Filed: |
January 28, 2005 |
PCT Filed: |
February 4, 2003 |
PCT NO: |
PCT/GB03/00504 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10502902 |
Jan 28, 2005 |
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10067020 |
Feb 4, 2002 |
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6858596 |
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10067020 |
Feb 4, 2002 |
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09958050 |
Oct 2, 2001 |
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09958050 |
Oct 2, 2001 |
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PCT/GB01/03495 |
Aug 3, 2001 |
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Current U.S.
Class: |
514/172 |
Current CPC
Class: |
A61K 9/0078 20130101;
A61K 9/0043 20130101; A61P 37/08 20180101; A61K 47/38 20130101;
A61P 5/44 20180101; A61K 31/56 20130101; A61P 29/00 20180101; A61K
31/58 20130101; A61P 11/02 20180101 |
Class at
Publication: |
514/172 |
International
Class: |
A61K 031/58 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 5, 2000 |
GB |
GB 0019172.6 |
Claims
1-4. (canceled)
5. A pharmaceutical formulation comprising a pharmaceutical
formulation which comprises: an aqueous suspension of particulate
compound of formula (I) 8or a solvate thereof, and one or more
preservatives, wherein the preservative comprises disodium
edatate.
6-8. (canceled)
9. A pharmaceutical formulation according to claim 5 which further
comprises one or more wetting agents.
10. A pharmaceutical formulation according to claim 9 wherein the
wetting agent comprises polyoxyethylene (20) sorbitan
monooleate.
11. A pharmaceutical formulation according to claim 9 wherein the
wetting agent is present within the formulation in an amount of
between 0.001 and 0.05% (w/w), based on the total weight of the
formulation.
12. A pharmaceutical formulation according to claim 5 which further
comprises: one or more isotonicity adjusting agents.
13. A pharmaceutical formulation according to claim 12 wherein the
isotonicity adjusting agent comprises dextrose.
14. A pharmaceutical formulation according to claim 12 wherein the
isotonicity adjusting agent is present within the formulation in an
amount of between 0.1 and 10% (w/w), based on the total weight of
the formulation.
15. A pharmaceutical formulation according to claim 12
characterised in that it is isotonic with fluids of the nasal
cavity.
16. A pharmaceutical formulation according to claim 12 which is pH
adjusted to between 5 and 7.
17. A pharmaceutical formulation according to claim 16 which is pH
adjusted using hydrochloric acid and/or sodium hydroxide
18. A pharmaceutical formulation according to claim 5 wherein the
compound of formula (I) or solvate thereof is present within the
formulation in an amount between 0.005% and 1% (w/w), based on the
total weight of the formulation.
19. A pharmaceutical formulation according to claim 5 wherein the
particles of the compound of formula (I) have a mass mean diameter
of between 0.5 and 10 .mu.m.
20. A pharmaceutical formulation according to claim 19 wherein the
particles of the compound of formula (I) have a mass mean diameter
of between 1 and 5 .mu.m.
21. A pharmaceutical formulation according to claim 5 wherein the
compound of formula (I) is in the form of unsolvated Form 1
polymorph.
22. A pharmaceutical formulation which comprises: an aqueous
suspension of particulate compound of formula (I) 9or a solvate
thereof wherein the particle size of the compound of formula (I)
has been reduced.
23. A pharmaceutical composition as claimed in claim 22 wherein the
particle size has been reduced by micronisation.
24. A pharmaceutical composition as claimed in claim 22 wherein the
particle size has been reduced by microfluidisation.
25. A pharmaceutical formulation as claimed in claim 22, wherein
the compound of formula (I) was substantially in the form of equant
or substantially equant particles, prior to particle size
reduction.
26. A pharmaceutical formulation as claimed in claim 22 wherein the
compound of formula (I) was substantially in the form of tetragonal
bipyramidal or substantially tetragonal bipyramidal particles prior
to particle size reduction.
27. A pharmaceutical formulation as claimed in claim 23 wherein the
compound of formula (I) is substantially in the form of acicular
particles.
28. A pharmaceutical formulation according to claim 22 which
comprises (i) one or more suspending agents; (ii) one or more
preservatives; (iii) one or more wetting agents; and (iv) one or
more isotonicity adjusting agents
29. A pharmaceutical formulation according to claim 28 wherein the
suspending agent is microcrystalline cellulose and carboxy
methylcellulose sodium, the preservative is EDTA and benzalkonium
chloride, the wetting agent is polyoxyethylene (20) sorbitan
monooleate and the isotonicity adjusting agent is dextrose.
30. A pharmaceutical formulation according to claim 22 which
comprises another therapeutically active agent.
31. A pharmaceutical formulation according to claim 30, wherein the
other therapeutically active agent is an anti-histamine or an
anti-allergic.
32. A container comprising a pharmaceutical formulation which
comprises: an aqueous suspension of particulate compound of formula
(I) 10or a solvate thereof wherein the particle size of the
compound of formula (I) has been reduced.
33. A device adapted for intranasal delivery of a pharmaceutical
formulation comprising a container according to claim 32.
34. A compound of formula (I) 11substantially in the form of equant
or substantially equant particles.
35. A compound as claimed in claim 34 wherein the particles are in
the form of tetragonal bipyramidal or substantially tetragonal
bipyramidal particles.
36. A compound of formula (I) 12substantially in the form of
acicular particles.
37. A method of treatment of allergic rhinitis which comprises
administering to a patient a pharmaceutically acceptable amount of
a formulation according to claim 22.
38. The method according to claim 37 wherein the administration is
once-per-day.
39. A pharmaceutical formulation as claimed in claim 22 for use in
human or veterinary medicine in the treatment of patients with an
inflammatory and/or an allergic condition.
40. A pharmaceutical formulation as claimed in claim 39 for use in
treatment once-per-day.
41. A process for the manufacture of a medicament for the treatment
of patients with an inflammatory and/or allergic condition
comprising preparing a pharmaceutical formulation according to
claim 22.
42. (canceled)
43. A process for the preparation of a compound of formula (I)
substantially in the form of equant or substantially equant
particles which process comprises dissolving a compound of formula
(I) in a suitable solvating solvent and crystallising the
compound.
44. A process as claimed in claim 43 wherein the solvating solvent
is acetone, propan-2-ol, ethylacetate or tetrahydrofuran.
45. A process as claimed in claim 44 wherein the solvating agent is
acetone pr propan-2-ol.
46. A process as claimed in claim 43 wherein the compound of
formula (I) is substantially in the form of tetragonal bipyramidal
particles.
Description
[0001] This application is a Continuation-in-part of U.S. patent
application Ser. No. 09/958050 filed on 2 Oct. 2001, which is a 35
USC 371 US National Phase of International Patent Application No.
PCT.GB01.03495 filed 3 Aug. 2001, which claims priority from United
Kingdom Patent Application No. GB 0019172.6 filed 5 Aug. 2000.
[0002] The present invention relates to pharmaceutical formulations
containing an anti-inflammatory and anti-allergic compound of the
androstane series and to processes for their preparation. The
present invention also relates to therapeutic uses thereof,
particularly for the treatment of inflammatory and allergic
conditions.
[0003] Glucocorticoids which have anti-inflammatory properties are
known and are widely used for the treatment of inflammatory
disorders or diseases such as asthma and rhinitis. For example,
U.S. Pat. No. 4,335,121 discloses
6.alpha.,9.alpha.-Difluoro-17.alpha.-(1-oxopropoxy)-1-
1.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-diene-17.beta.-carboth-
ioic acid S-fluoromethyl ester (known by the generic name of
fluticasone propionate) and derivatives thereof. The use of
glucocorticoids generally, and especially in children, has been
limited in some quarters by concerns over potential side effects.
The side effects that are feared with glucocorticoids include
suppression of the Hypothalamic-Pituitary-Ad- renal (HPA) axis,
effects on bone growth in children and on bone density in the
elderly, ocular complications (cataract formation and glaucoma) and
skin atrophy. Certain glucocorticoid compounds also have complex
paths of metabolism wherein the production of active metabolites
may make the pharmacodynamics and pharmacokinetics of such
compounds difficult to understand. Whilst the modem glucocorticoids
are very much safer than those originally introduced, it remains an
object of research to produce new molecules and formulations of old
and new molecules which have excellent anti-inflammatory
properties, with predictable pharmacokinetic and pharmacodynamic
properties, with an attractive side effect profile, and with a
convenient treatment regime.
[0004] In PCT.GB01.03495 we have a novel glucocorticoid compound
which substantially meets these objectives. We have now identified
a formulation of the novel glucocortoid compound in particular one
suitable for intranasal administration.
[0005] Many millions of individuals suffer from seasonal and
perennial allergic rhinitis worldwide. Symptoms of seasonal and
perennial allergic rhinitis include nasal itch, congestion, runny
nose, sneezing and watery eyes. Seasonal allergic rhinitis is
commonly known as `hay fever`. It is caused by allergens which are
present in the air at specific times of the year, for example tree
pollen during Spring and Summer. Perennial allergic rhinitis is
caused by allergens which are present in the environment during the
entire year, for example dust mites, mould, mildew and pet
dander.
[0006] To formulate an effective pharmaceutical nasal composition,
the medicament must be delivered readily to all portions of the
nasal cavities (the target tissues) where it performs its
pharmacological function. Additionally, the medicament should
remain in contact with the target tissues for relatively long
periods of time. The longer the medicament remains in contact with
the target tissues, the medicament must be capable of resisting
those forces in the nasal passages that function to remove
particles from the nose. Such forces, referred to as `mucociliary
clearance`, are recognised as being extremely effective in removing
particles from the nose in a rapid manner, for example, within
10-30 minutes from the time the particles enter the nose.
[0007] Other desired characteristics of a nasal composition are
that it must not contain ingredients which cause the user
discomfort, that it has satisfactory stability and shelf-life
properties, and that it does not include constituents that are
considered to be detrimental to the environment, for example ozone
depletors. In the case of administration of glucocorticoids, the
potential for any undesirable side effects should preferably be
minimised.
[0008] Thus, according to one aspect of the invention, there is
provided a pharmaceutical formulation comprising an aqueous
suspension of particulate compound of formula (I) 2
[0009] or a solvate thereof.
[0010] Preferably, the formulation will contain one or more
suspending agents.
[0011] Preferably, the formulation will contain one or more
preservatives.
[0012] Preferably, the formulation will contain one or more wetting
agents.
[0013] Preferably, the formulation will contain one or more
isotonicity adjusting agents.
[0014] According to one particular aspect of the present invention
we provide a pharmaceutical formulation which comprises:
[0015] (i) an aqueous suspension of particulate compound of formula
(I) or a solvate thereof;
[0016] (ii) one or more suspending agents;
[0017] (iii) one or more preservatives;
[0018] (iv) one or more wetting agents; and
[0019] (v) one or more isotonicity adjusting agents.
[0020] The formulations of the present invention may be stabilised
by appropriate selection of pH. Typically, the pH will be adjusted
to between 4.5 and 7.5, preferably between 5.0 and 7.0, especially
around 6.0.
[0021] Examples of pharmaceutically acceptable materials which can
be used to adjust the pH of the formulation include hydrochloric
acid and sodium hydroxide. Preferably, the pH of the formulation
will be adjusted using hydrochloric acid.
[0022] The aqueous component is preferably a high grade quality of
water, most preferably purified water.
[0023] The active compound of formula (I) or solvate thereofwill
suitably have a mass mean diameter (MMD) of less than 20 .mu.m,
preferably between 0.5-10 .mu.m, especially between 1-5 .mu.m. If
particle size reduction is necessary, this may be achieved by
techniques such as micronisation and/or microfluidisation.
[0024] Particularly preferred MMDs are between 2-4 .mu.m.
[0025] In some preferred embodiments, if necessary, particle size
reduction may be achieved by micronisation.
[0026] In other preferred embodiments, particle size reduction may
be achieved by microfluidisation.
[0027] Preferably, the particles will be crystalline, prepared for
example by a process which comprises mixing in a continuous flow
cell in the presence of ultrasonic radiation a flowing solution of
compound of formula (I) or solvate thereof as medicament in a
liquid solvent with a flowing liquid antisolvent for said
medicament (as described in International Patent Application
PCT.GB99.04368).
[0028] A pharmaceutically effective amount of particulate compound
of formula (I) or solvate thereof is present within the
formulation, in an amount which is preferably between 0.005% and 1%
(w/w), preferably between 0.01% and 0.5% (w/w), especially
0.05-0.1% (w/w) based on the total weight of the formulation.
Typically, 50.mu.l of suspension will contain 50.mu.g of compound
of formula (I) or solvate thereof.
[0029] Examples of suspending agents include
carboxymethylcellulose, veegum, tragacanth, bentonite,
methylcellulose and polyethylene glycols. Preferably, the
suspending agent will be microcrystalline cellulose and carboxy
methylcellulose sodium, most preferably used as the branded product
Avicel RC591 (which typically contains 87-91% microcrystalline
cellulose and 9-13% carboxy methylcellulose sodium). Particulate
microcrystalline cellulose will preferably have a particle size in
the range 1 to 100 .mu.m. We believe that Avicel RC591 acts as a
suspending agent by imparting thixotropic properties to the
formulation, wherein the formulation may become a stable suspension
upon being stirred, shaken or otherwise disturbed.
[0030] Preferably, the thixotropic nature of the suspending agent
will ensure that the formulation assumes a gel like appearance at
rest, wherein the particulate medicament is dispersed and suspended
substantially uniformly, characterised by a high viscosity value.
Once the composition is subjected to shear forces, such as those
caused by agitation prior to spraying, the viscosity of the
formulation will preferably decrease to such a level to enable it
to flow readily through the spray device and exit as a spray of
fine particles in a mist. These particles will then be capable of
infiltrating the mucosal surfaces of the anterior regions of the
nose (frontal nasal cavities), the frontal sinus, the maxillary
sinuses and the turbinates which overlie the conchas of the nasal
cavities. Once deposited, the viscosity of the formulation will
preferably increase to a sufficient level to assume its gel-like
form and resist being cleared from the nasal passages by the
inherent mucocillary forces that are present in the nasal
cavities.
[0031] When the formulation of the present invention comprises a
suspending agent, it will be desirably added in a suitable amount
to achieve this function, preferably the suspending agent will be
present within the formulation in an amount of between 0.1 and 5%
(w/w), especially 1.5% (w/w), based on the total weight of the
formulation.
[0032] For stability purposes, the formulation of the present
invention should be protected from microbial contamination and
growth by inclusion of a preservative. Examples of pharmaceutically
acceptable anti-microbial agents or preservatives that can be used
in the formulation include quaternary ammonium compounds (eg.
benzalkonium chloride, benzethonium chloride, cetrimide and
cetylpyridinium chloride), mercurial agents (eg. phenylmercuric
nitrate, phenylmercuric acetate and thimerosal), alcoholic agents
(eg. chlorobutanol, phenylethyl alcohol and benzyl alcohol),
antibacterial esters (eg. esters of para-hydroxybenzoic acid),
chelating agents such as disodium edetate (EDTA) and other
anti-microbial agents such as chlorhexidine, chlorocresol, sorbic
acid and its salts and polymyxin.
[0033] Preferably the preservative will comprise disodium edetate
(EDTA), which will preferably be present within the formulation in
an amount of between 0.001 and 1% (w/w), especially around 0.015%
(w/w), based on the total weight of the formulation.
[0034] Preferably, the preservative will comprise benzalkonium
chloride (BKC), which will preferably be present within the
formulation in an amount of between 0.001 and 1% (w/w), especially
around 0.015% (w/w), based on the total weight of the
formulation.
[0035] More preferably, the preservative comprises disodium edetate
and benzalkonium chloride or disodium edetate and potassium
sorbate, particularly disodium edetate and benzalkonium
chloride.
[0036] Formulations, eg nasal formulations which contain a
suspended medicament (such as a compound of formula (I) or a
solvate thereof) will preferably contain a pharmaceutically
acceptable wetting agent which functions to wet the particles of
medicament to facilitate dispersion thereof in the aqueous phase of
the composition. Preferably, the amount of wetting agent used will
not cause foaming of the dispersion during mixing.
[0037] It will be appreciated that any agent which is effective in
wetting the particles and which is pharmaceutically acceptable can
be used. Examples of wetting agents that can be used are fatty
alcohols, esters and ethers. Preferably, the wetting agent will be
a hydrophilic, non-ionic surfactant, most preferably
polyoxyethylene (20) sorbitan monooleate (supplied as the branded
product Polysorbate 80).
[0038] Wherein the formulation of the present invention comprises a
wetting agent, it will be desirably added in a sufficient quantity
to achieve this function, preferably the wetting agent will be
present within the formulation in an amount of between 0.001 and
0.05% (w/w), especially 0.025% (w/w), based on the total weight of
the formulation.
[0039] The presence of an isotonicity adjusting agent is to achieve
isotonicity with body fluids eg fluids of the nasal cavity,
resulting in reduced levels of irritancy associated with many nasal
formulations. Examples of suitable isotonicity adjusting agents are
sodium chloride, dextrose and calcium chloride. Preferably, the
isotonicity adjusting agent will be dextrose, most preferably used
as anhydrous dextrose.
[0040] When the formulation of the present invention comprises an
isotonicity adjusting agent it will be desirably added in a
sufficient quantity to achieve this function, preferably the
isotonicity adjusting agent will be present within the formulation
in an amount of between 0.1 and 10% (w/w), especially 5.0% w/w,
based on the total weight of the formulation.
[0041] In the pharmaceutical formulation of the invention, the
compound of formula (I) or solvate thereof is present within the
formulation in an amount between 0.005% and 1% (w/w), based on the
total weight of the formulation.
[0042] In the pharmaceutical formulation of the invention,
preferably the suspending agent is microcrystalline cellulose and
carboxy methylcellulose sodium, the preservative is EDTA and
benzalkonium chloride, the wetting agent is polyoxyethylene (20)
sorbitan monooleate and the isotonicity adjusting agent is
dextrose.
[0043] The compound of formula (I) or a solvate thereof and
formulations thereof have potentially beneficial anti-inflammatory
or anti-allergic effects, particularly upon topical administration
to the nose, demonstrated by, for example, its ability to bind to
the glucocorticoid receptor and to illicit a response via that
receptor, with long acting effect. Hence, formulations according to
the invention are useful in the treatment of inflammatory and/or
allergic disorders of the nose, especially in once-per-day
therapy.
[0044] Formulations according to the invention may be prepared by
combining the ingredients in water. If necessary the pH may be
adjusted as a final step. Formulations so prepared may then be
filled into the receptacle.
[0045] Aqueous formulations of the invention may also be employed
for rectal, aural, otic, oral, topical or parenteral administration
or administration by inhalation for the treatment of other local
inflammatory conditions (eg dermatitis, asthma, chronic obstructive
pulmonary disease (COPD) and the like). For example formulations of
the invention may be administered to the lung by nebulisation. Such
formulations may employ excipients (eg preservatives, buffers and
the like) appropriate for the route of administration.
[0046] The particularly desirable biological properties of the
compound of formula (I) are now explained below:
[0047] Compound or formula (I) undergoes highly efficient hepatic
metabolism to yield the 17-.beta. carboxylic acid (X) as the sole
major metabolite in (at and human in vitro systems. This metabolite
has been synthesised and demonstrated to be >1000 fold less
active than the parent compound in in vitro functional
glucocortcoid assays. 3
[0048] This efficient hepatic metabolism is reflected by in vivo
data in the rat, which have demonstrated plasma clearance at a rate
approaching hepatic blood flow and an oral bioavailability of
<1%, consistent with extensive first-pass metabolism.
[0049] In vitro metabolism studies in human hepatocytes have
demonstrated that compound (I) is metabolised in a similar manner
to fluticasone propionate but that conversion of (I) to the
inactive acid metabolite occurs approximately 5-fold more rapidly
than with fluticasone propionate. This very efficient hepatic
inactivation would be expected to minimise systemic exposure in man
leading to an improved safety profile.
[0050] Examples of disease states in which the compound of formula
(I) has utility include inflammatory and/or allergic conditions of
the nasal passages such as rhinitis eg seasonal and perennial
rhinitis as well as other local inflammatory conditions such as
asthma, COPD and dermatitis.
[0051] It will be appreciated by those skilled in the art that
reference herein to treatment extends to prophylaxis as well as the
treatment of established conditions.
[0052] Preferable means for applying the formulation of the present
invention to the nasal passages is by use of a pre-compression
pump, such as a VP3, VP7 or modifications, model manufactured by
Valois SA. Advantages of pumps of this type are beneficial as they
will ensure that the formulation is not released or atomised until
a sufficient force has been applied, otherwise smaller doses may be
applied. Typically, these pre-compression pumps may be used with a
bottle (glass or plastic) capable of holding 8-50 ml of a
formulation. Each spray will typically deliver 50-100 .mu.l of such
a formulation, therefore, the device is capable of providing at
least 100 metered doses.
[0053] A suitable dosing regime for the formulation of the present
invention when administered to the nose would be for the patient to
inhale slowly through the nose subsequent to the nasal cavity being
cleared. During inhalation the formulation would be applied to one
nostril while the other is manually compressed. This procedure
would then be repeated for the other nostril.
[0054] Typically, one or two inhalations per nostril would be
administered by the above procedure up to three times each day,
ideally once daily.
[0055] It will be appreciated that the above dosing regime should
be adjusted according to the patient's age, body weight and/or
symptom severity.
[0056] As mentioned above, formulations comprising a compound of
formula (I) or solvate thereof are useful in human or veterinary
medicine, in particular as an anti-inflammatory and anti-allergic
agent.
[0057] There is thus provided as a further aspect of the invention
a formulation comprising the compound of formula (I) or solvate
thereof for use in human or veterinary medicine, particularly in
the treatment of patients with inflammatory and/or allergic
conditions.
[0058] According to another aspect of the invention, there is
provided the use of a formulation comprising the compound of
formula (I) or solvate thereof for the manufacture of a medicament
for the treatment of patients with inflammatory and/or allergic
conditions.
[0059] In a further or alternative aspect, there is provided a
method for the treatment of a human or animal subject with an
inflammatory and/or allergic condition, which method comprises
administering to said human or animal subject an effective amount
of a formulation comprising the compound of formula (I) or solvate
thereof.
[0060] The compound of formula (I) is long-acting, therefore
preferably the compound will be delivered once-per-day and the dose
will be selected so that the compound has a therapeutic effect in
the treatment of respiratory disorders (eg rhinitis) over 24 hours
or more.
[0061] The pharmaceutical compositions according to the invention
may also be used in combination with another therapeutically active
agent, for example, an anti-histamine or an anti-allergic. The
invention thus provides, in a further aspect, a combination
comprising a compound of formula (I) or a physiologically
acceptable salt or solvate thereof together with another
therapeutically active agent, for example, an anti-histamine or an
anti-allergic.
[0062] Examples of anti-histamines include methapyrilene or
loratadine.
[0063] Other suitable combinations include, for example, other
anti-inflammatory agents eg. NSAIDs (eg. PDE4 inhibitors,
leukotriene antagonists, iNOS inhibitors, tryptase and elastase
inhibitors, beta-2 integrin antagonists and adenosine 2a agonists))
or antiinfective agents (eg. antibiotics, antivirals).
[0064] Of particular interest is use of the compounds of formula
(I) in combination with a phosphodiesterase 4 (PDE4) inhibitor. The
PDE4-specific inhibitor useful in this aspect of the invention may
be any compound that is known to inhibit the PDE4 enzyme or which
is discovered to act as a PDE4 inhibitor, and which are only PDE4
inhibitors, not compounds which inhibit other members of the PDE
family as well as PDE4. Generally it is preferred to use a PDE4
inhibitor which has an IC.sub.50 ratio of about 0.1 or greater as
regards the IC.sub.50 for the PDE4 catalytic form which binds
rolipram with a high affinity divided by the IC.sub.50 for the form
which binds rolipram with a low affinity. For the purposes of this
disclosure, the CAMP catalytic site which binds R and S rolipram
with a low affinity is denominated the "low affinity" binding site
(LPDE 4) and the other form of this catalytic site which binds
rolipram with a high affinity is denominated the "high affinity"
binding site (HPDE 4). This term "HPDE4" should not be confused
with the term "hPDE4" which is used to denote human PDE4.
[0065] The pharmaceutical formulation according to the invention
may further comprise one or more excipients. By the term
"excipient", as used herein, it is meant to mean substantially
inert materials that are nontoxic and do not interact with other
components of a composition in a deleterious manner including, but
not limited to, pharmaceutical grades of: carbohydrates, organic
and inorganic salts, polymers, amino acids, phospholipids, wetting
agents, emulsifiers, surfactants, poloxamers, pluronics, and ion
exchange resins, and combinations thereof, a non-exhaustive list of
examples of which are provided below:
[0066] Carbohydrates, including: monosaccharides, such as, but not
limited to, fructose; disaccharides, such as, but not limited to
lactose, and combinations and derivatives thereof; polysaccharides,
such as, but not limited to, cellulose and combinations and
derivatives thereof; oligosaccharides, such as, but not limited to,
dextrins, and combinations and derivatives thereof; polyols, such
as but not limited to sorbitol, and combinations and derivatives
thereof;
[0067] Organic and inorganic salts, including but not limited to
sodium or calcium phosphates, magnesium stearate, and combinations
and derivatives thereof;
[0068] Polymers, including: natural biodegradable protein polymers
including, but not limited to, gelatin and combinations and
derivatives thereof;
[0069] Natural biodegradable polysaccharide polymers including, but
not limited to, chitin and starch, crosslinked starch, and
combinations and derivatives thereof;
[0070] Semisynthetic biodegradable polymers including, but not
limited to, derivatives of chitosan;
[0071] Synthetic biodegradable polymers including but not limited
to polyethylene glycols (PEG), polylactic acid (PLA), synthetic
polymers including but not limited to polyvinyl alcohol and
combinations and derivatives thereof;
[0072] Amino acids including but not limited to including non-polar
amino acids, such as leucine and combinations and derivatives
thereof;
[0073] Phospholipids, including lecithins and combinations and
derivatives thereof;
[0074] Wetting agents/Surfactants/Emulsifiers, including, but not
limited to gum acacia, cholesterol, fatty acids including,
combinations and derivatives thereof;
[0075] Poloxamers/Pluronics: including but not limited to poloxamer
188, Pluronic.RTM. F-108, and combinations and derivations
thereof;
[0076] Ion exchange resins: including but not limited to amberlite
IR120 and combinations and derivatives thereof,
[0077] and combinations of the noted excipients.
[0078] Further, there is provided a process for the preparation of
such pharmaceutical compositions which comprises mixing the
ingredients.
[0079] The individual compounds of such combinations may be
administered either sequentially in separate pharmaceutical
compositions as well as simultaneously in combined pharmaceutical
formulations. Preferably additional therapeutically active
ingredients are suspended in the formulation together with the
compound of formula (I). Appropriate doses of known therapeutic
agents will be readily appreciated by those skilled in the art
[0080] A process for preparing a compound of formula (I) comprises
alkylation of a thioacid of formula (II) 4
[0081] or a salt thereof.
[0082] In this process the compound of formula (II) may be reacted
with a compound of formula FCH.sub.2L wherein L represents a
leaving group (eg a halogen atom, a mesyl or tosyl group or the
like) for example, an appropriate fluoromethyl halide under
standard conditions. Preferably, the fluoromethyl halide reagent is
bromofluoromethane. Preferably the compound of formula (II) is
employed as a salt, particularly the salt with
diisopropylethylamine.
[0083] In a preferred process for preparing the compound of formula
(I), the compound of formula (II) or a salt thereof is treated with
bromofluoromethane optionally in the presence of a phase transfer
catalyst A preferred solvent is methylacetate, or more preferably
ethylacetate, optionally in the presence of water. The presence of
water improves solubility of both starting material and product and
the use of a phase transfer catalyst results in an increased rate
of reaction. Examples of phase transfer catalysts that may be
employed include (but are not restricted to) tetrabutylammonium
bromide, tetrabutylammonium chloride, benzyltributylammonium
bromide, benzyltributylammonium chloride, benzyltriethylammonium
bromide, methyltributylammonium chloride and methyltrioctylammonium
chloride. THF has also successfully been employed as solvent for
the reaction wherein the presence of a phase transfer catalyst
again provides a significantly faster reaction rate. Preferably the
product present in an organic phase is washed firstly with aqueous
acid eg dilute HCl in order to remove amine compounds such as
triethylamine and diisopropylethylamine and then with aqueous base
eg sodium bicarbonate in order to remove any unreacted precursor
compound of formula (II).
[0084] Compound of formula (i) in unsolvated form may be prepared
by a process comprising:
[0085] (a) Crystallising the compound of formula (I) in the
presence of a non-solvating solvent such as ethanol, methanol,
water, ethyl acetate, toluene, methylisobutylketone or mixtures
thereof; or
[0086] (b) Desolvating a compound of formula (I) in solvated form
(eg in the form of a solvate with acetone, isopropanol,
methylethylketone, DMF or tetrahydrofuran) eg by heating.
[0087] In step (b) the desolvation will generally be performed at a
temperature exceeding 50.degree. C. preferably at a temperature
exceeding 100.degree. C. Generally heating will be performed under
vacuum.
[0088] Compound of formula (I) in unsolvated form has been found to
exist in 3 crystalline polymorphic forms, Forms 1, 2 and 3. The
Forms are characterised by their X-ray diffraction (XRPD) patterns
Broadly speaking the Forms are characterised. in their XRPD
profiles as follows:
[0089] Form 1: Peak at around 18.9 degrees 2Theta
[0090] Form 2: Peaks at around 18.4 and 21.5 degrees 2Theta
[0091] Form 3: Peaks at around 18.6 and 19.2 degrees 2Theta.
[0092] Unsolvated polymorph Form 1 appears likely to be the
thermodynamically most stable form since Forms 2 and 3 are
converted into Form I on heating. Polymorph Form 1 is
preferred.
[0093] In some embodiments we prefer the compound of formula (I) in
unsolvated polymorph Form 1 substantially to be in the form of
equant or substantially equant particles. Substantially equant
particles have dimensions in the X, Y and Z dimensions which are
similar in length.
[0094] Another aspect of the present invention provides compounds
of formula (I) substantially in the form of equant or substantially
equant particles.
[0095] Preferably, the equant particles will be in the form of
tetragonal bipyramidal or substantially tetragonal bipyramidal
particles.
[0096] Tetragonal bipyramidal particles of Form 1 polymorph have
surprisingly been found to produce relatively consistent sized
particles after micronisation, which appears to be independent of
the drying process prior to micronisation. The tetragonal
bipyramidal particles possess good flow properties, good bulk
density, and are easily isolated from suspension by filtration.
[0097] In other embodiments we prefer the compound of formula (I)
in unsolvated polymorph Form 1 to be in the form of acicular
particles. Acicular particles are needle-like in shape.
[0098] Another aspect of the present invention provides compounds
of formula (I) substantially in the form of acicular particles.
[0099] Acicular particles of Form 1 have surprisingly been found to
produce relatively varying sized particle distribution after
micronisation, and particle sizes which, on average, are larger
than those produced from micronisation of tetragonal bipyramidal
particles. In certain circumstances where this size profile of
micronised product is preferred, then acicular particles will be
preferred. It may be that the micronised product produced from
acicular particles will result in lower systemic exposure to the
active compound.
[0100] A process for preparing a compound of formula (I) as
unsolvated Form 1 polymorph comprises dissolving compound of
formula (I) in methylisobutylketone, ethyl acetate or methyl
acetate and producing compound of formula (I) as unsolvated Form 1
by addition of a non-solvating anti-solvent such as iso-octane or
toluene.
[0101] According to a first preferred embodiment of this process
the compound of formula (I) may be dissolved in ethyl acetate and
compound of formula (I) as unsolvated Form I polymorph may be
obtained by addition of toluene as anti-solvent In order to improve
the yield, preferably the ethyl acetate solution is hot and once
the toluene has been added the mixture is distilled to reduce the
content of ethyl acetate.
[0102] According to a second preferred embodiment of this process
the compound of formula (I) may be dissolved in
methylisobutylketone and compound of formula (I) as unsolvated Form
1 polymorph may be obtained by addition of isooctane as
anti-solvent
[0103] Compound of formula (I) in solvated form may be prepared by
crystallising the compound of formula (I) from a solvating solvent
such as acetone, propan-2-ol, ethylacetate or tetrahydrofuran
(THF).
[0104] Preferably in processes for preparing formulations of the
invention, the compound of formula (I) will be employed in
unsolvated form, typically unsolvated Form 1.
[0105] Thus, according to another aspect of the present invention
there is provided a process for the preparation of a compound of
formula (I), substantially in the form of equant or substantially
equant particles which process comprises dissolving a compound of
formula (I) in a suitable solvating solvent and crystallising the
compound
[0106] Preferred solvating agents are acetone, propan-2-ol,
ethylacetate or tetrahydrofuran, more preferably acetone or
propan-2-ol.
[0107] The compound of formula (I) is preferably substantially in
the form of tetragonal bipyramidel particles.
[0108] Compounds of formula (II) may be prepared from the
corresponding 17.alpha.-hydroxyl derivative of formula (III): 5
[0109] using for example, the methodology described by G. H.
Phillipps et al., (1994) Journal of Medicinal Chemistry, 37,
3717-3729. For example the step typically comprises the addition of
a reagent suitable for performing the esterification eg an
activated derivative of 2-furoic acid such as an activated ester or
preferably a 2-furoyl halide eg 2-furoyl chloride (employed in at
least 2 times molar quantity relative to the compound of formula
(III)) in the presence of an organic base eg triethylamine. The
second mole of 2-furoyl chloride reacts with the thioacid moiety in
the compound of formula (III) and needs to be removed eg by
reaction with an amine such as diethylamine.
[0110] This method suffers disadvantages, however, in that the
resultant compound of formula (II) is not readily purified of
contamination with the by-product 2-furoyldiethylamide. We have
therefore invented several improved processes for performing this
conversion.
[0111] In a first such improved process we have discovered that by
using a more polar amine such as diethanolamine, a more water
soluble by-product is obtained (in this case
2-furoyldiethanolamide) which permits compound of formula (II) or a
salt thereof to be produced in high purity since the by-product can
efficiently be removed by water washing.
[0112] Thus we provide a process for preparing a compound of
formula (II) which comprises:
[0113] (a) reacting a compound of formula (III) with an activated
derivative of 2-furoic acid as in an amount of at least 2 moles of
the activated derivative per mole of compound of formula (III) to
yield a compound of formula (IIA); 6
[0114] and
[0115] (b) removal of the sulphur-linked 2-furoyl moiety from
compound of formula (IIA) by reaction of the product of step (a)
with an organic primary or secondary amine base capable of forming
a water soluble 2-furoyl amide.
[0116] In two particularly convenient embodiments of this process
we also provide methods for the efficient purification of the end
product which comprise either
[0117] (c1)when the product of step (b) is dissolved in a
substantially water immiscible organic solvent, purifying the
compound of formula (II) by washing out the amide by-product from
step (b) with an aqueous wash, or
[0118] (c2) when the product of step (b) is dissolved in a water
miscible solvent, purifying the compound of formula (II) by
treating the product of step (b) with an aqueous medium so as to
precipitate out pure compound of formula (II) or a salt
thereof;
[0119] In step (a) preferably the activated derivative of 2-furoic
acid may be an activated ester of 2-furoic acid, but is more
preferably a 2-furoyl halide, especially 2-furoyl chloride. A
suitable solvent for this reaction is ethylacetate or methylacetate
(preferably methylacetate) (when step (c1) may be followed) or
acetone (when step (c2) may be followed). Normally an organic base
eg triethylamine will be present. In step (b) preferably the
organic base is diethanolamine. The base may suitably be dissolved
in a solvent eg methanol. Generally steps (a) and (b) will be
performed at reduced temperature eg between 0 and 5.degree. C. In
step (c1) the aqueous wash may be water, however the use of brine
results in higher yields and is therefore preferred. In step (c2)
the aqueous medium is for example a dilute aqueous acid such as
dilute HCl.
[0120] We also provide an alternative process for preparing a
compound of formula (II) which comprises:
[0121] (a) reacting a compound of formula (III) with an activated
derivative of 2-furoic acid in an amount of at least 2 moles of
activated derivative per mole of compound of formula (III) to yield
a compound of formula (IIA); and
[0122] (b) removal of the sulphur-linked 2-furoyl moiety from
compound of formula (IIA) by reaction of the product of step (a)
with a further mole of compound of formula (III) to give two moles
of compound of formula (II).
[0123] In step (a) preferably the activated derivative of 2-furoic
acid may be an activated ester of 2-furoic acid, but is more
preferably a 2-furoyl halide, especially 2-furoyl chloride. A
suitable solvent for his step is acetone. Normally an organic base
eg triethylamine will be present. In step (b) a suitable solvent is
DMF or dimethylacetamide. Normally an organic base eg triethylamine
will be present. Generally steps (a) and (b) will be performed at
reduced temperature eg between 0 and 5.degree. C. The product may
be isolated by treatment with acid and washing with water.
[0124] This aforementioned process is very efficient in that it
does not produce any furoylamide by-product (thus affording inter
alia environmental advantages) since the excess mole of furoyl
moiety is taken up by reaction with a further mole of compound of
formula (II) to form an additional mole of compound of formula
(II).
[0125] Further general conditions for the conversion of compound of
formula (III) to compound of formula (II) in the two processes just
described will be well known to persons skilled in the art.
[0126] According to a preferred set of conditions, however, we have
found that the compound of formula (II) may advantageously be
isolated in the form of a solid crystalline salt. The preferred
salt is a salt formed with a base such as triethylamine,
2,4,6-trimethylpyridine, diisopropylethylamine or
N-ethylpiperidine. Such salt forms of compound of formula (II) are
more stable, more readily filtered and dried and can be isolated in
higher purity than the free thioacid. The most preferred salt is
the salt formed with diisopropylethylamine. The triethylamine salt
is also of interest.
[0127] Compounds of formula (III) may be prepared in accordance
with procedures described in GB 2088877B. Compounds of formula
(III) may also be prepared by a process comprising the following
steps: 7
[0128] Step (a) comprises oxidation of a solution containing the
compound of formula (V). Preferably, step (a) will be performed in
the presence of a solvent comprising methanol, water,
tetrahydrofuran, dioxan or diethylene glygol dimethylether. So as
to enhance yield and throughput, preferred solvents are methanol,
water or tetrahydrofuran, and more preferably are water or
tetrahydrofuran, especially water and tetrahydrofuran as solvent.
Dioxan and diethylene glygol dimethylether are also preferred
solvents which may optionally (and preferably) be employed together
with water. Preferably, the solvent will be present in an amount of
between 3 and 10 vol relative to the amount of the starting
material (1 wt.), more preferably between 4 and 6 vol., especially
5 vol. Preferably the oxidising agent is present in an amount of
1-9 molar equivalents relative to the amount of the starting
material. For example, when a 50% w/w aqueous solution of periodic
acid is employed, the oxidising agent may be present in an amount
of between 1.1 and 10 wt. relative to the amount of the starting
material (1 wt), more preferably between 1.1 and 3 wt., especially
1.3 wt Preferably, the oxidation step will comprise the use of a
chemical oxidising agent. More preferably, the oxidising agent will
be periodic acid or iodic acid or a salt thereof. Most preferably,
the oxidising agent will be periodic acid or sodium periodate,
especially periodic acid. Alternatively (or in addition), it will
also be appreciated that the oxidation step may comprise any
suitable oxidation reaction, eg one which utilises air and/or
oxygen. When the oxidation reaction utilises air and/or oxygen, the
solvent used in said reaction will preferably be methanol.
Preferably, step (a) will involve incubating the reagents at room
temperature or a little warmer, say around 25.degree. C. eg for 2
hours. The compound of formula (IV) may be isolated by
recrystallisation from the reaction mixture by addition of an
anti-solvent. A suitable anti-solvent for compound of formula (IV)
is water. Surprisingly we have discovered that it is highly
desirable to control the conditions under which the compound of
formula (IV) is precipitated by addition of anti-solvent eg water.
When the recrystallisation is performed using chilled water (eg
water/ice mixture at a temperature of 0-5.degree. C.) although
better anti-solvent properties may be expected we have found that
the crystalline product produced is very voluminous, resembles a
soft gel and is very difficult to filter. Without being limited by
theory we believe that this low density product contains a large
amount of solvated solvent within the crystal lattice. By contrast
when conditions of around 10.degree. C. or higher are used (eg
around ambient temperature) a granular product of a sand like
consistency which is very easily filtered is produced. Under these
conditions, crystallisation typically commences after around 1 hour
and is typically completed within a few hours (eg 2 hours). Without
being limited by theory we believe that this granular product
contains little or no solvated solvent within the crystal
lattice.
[0129] Step (b) will typically comprise the addition of a reagent
suitable for converting a carboxylic acid to a carbothioic acid eg
using hydrogen sulphide gas together with a suitable coupling agent
eg carbonyldiimidazole (CDI) in the presence of a suitable solvent
eg dimethylformamide.
[0130] The advantages of the formulation of the compound of formula
(I) according to the invention may include the fact that the
formulations demonstrate excellent anti-inflammatory properties,
with predictable pharmacokinetic and pharmacodynamic behaviour,
with an attractive side-effect profile, rapid onset of action, long
duration of action, and are compatible with a convenient regime of
treatment in human patients, in particular being amendable to
once-per day dosing. Further advantages may include the fact that
the formulation has desirable physical and chemical properties
which allow for ready manufacture and storage.
[0131] According to another aspect of the invention there is
provided a container comprising a pharmaceutical formulation
according to the invention.
[0132] There is also provided a device adapted for intranasal
delivery of a pharmaceutical formulation comprising such a
container
[0133] Suitably the formulation will be dispensed from a vessel
fitted with a suitable pre-compression pump and nasal actuator,
adapted to dispense 50 or 100 .mu.l per actuation, preferably 50
.mu.l
[0134] The following non-limiting Examples illustrate the
invention:
EXAMPLES
[0135] General
[0136] .sup.1H-nmr spectra were recorded at 400 MHz and the
chemical shifts are expressed in ppm relative to tetramethylsilane.
The following abbreviations are used to describe the multiplicities
of the signals: s (singlet), d (doublet), t (triplet), q (quartet),
m (multiplet), dd (doublet of doublets), ddd (doublet of doublet of
doublets), dt (doublet of triplets) and b (broad). Biotage refers
to prepacked silica gel cartridges containing KP-Sil run on flash
12i chromatography module. LCMS was conducted on a Supelcosil
LCABZ+PLUS column (3.3 cm.times.4.6 mm ID) eluting with 0.1%
HCO.sub.2H and 0.01 M ammonium acetate in water (solvent A), and
0.05% HCO.sub.2H 5% water in acetonitrile (solvent B), using the
following elution gradient 0-0.7 min 0%B, 0.7-4.2 min 100%B,
4.2-5.3 min 0%B, 5.3-5.5 min 0%B at a flow rate of 3 ml/min. The
mass spectra were recorded on a Fisons VG Platform spectrometer
using electrospray positive and negative mode (ES+ve and
ES-ve).
[0137] Intermediates
[0138] Intermediate 1:
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcar-
bonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-diene-17.b-
eta.-carbothioic Acid Diisopropylethylamine Salt
[0139] A stirred suspension of
6.alpha.,9.alpha.-difluoro-11.beta.,17.alph-
a.-dihydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-diene-17.beta.-carbothioi-
c acid (prepared in accordance with the procedure described in GB
2088877B) (49.5 g) in methylacetate (500 ml) is treated with
triethylamine (35 ml) maintaining a reaction temperature in the
range 0-5.degree. C. 2-Furoyl chloride (25 ml) is added and the
mixture stirred at 0-5.degree. C. for 1 hour. A solution of
diethanolamine (52.8 g) in methanol (50 ml) is added and the
mixture stirred at 0-5.degree. C. for at least 2 hours. Dilute
hydrochloric acid (approx 1M, 550 ml) is added maintaining a
reaction temperature below 15.degree. C. and the mixture stirred at
15.degree. C. The organic phase is separated and the aqueous phase
is back extracted with methyl acetate (2.times.250 ml). All of the
organic phases are combined, washed sequentially with brine
(5.times.250 ml) and treated with di-isopropylethylamine (30 ml).
The reaction mixture is concentrated by distillation at atmospheric
pressure to an approximate volume of 250 ml and cooled to
25-30.degree. C. (crystallisation of the desired product normally
occurs during distillation/subsequent cooling). Tertiary butyl
methyl ether (TBME) (500 ml) is added, the slurry further cooled
and aged at 0-5.degree. C. for at least 10 minutes. The product is
filtered off, washed with chilled TBME (2.times.200 ml) and dried
under vacuum at approximately 40-50.degree. C. (75.3 g, 98.7%). NMR
(CDCl.sub.3) .delta.: 7.54-7.46 (1H, m), 7.20-7.12 (1H, dd),
7.07-6.99 (1H, dd), 6.48-6.41 (2H, m), 6.41-6.32 (1H, dd),
5.51-5.28 (1H, dddd .sup.2J.sub.H-F50 Hz), 4.45-4.33(1H, bd),
3.92-3.73 (3H, bm), 3.27-3.14 (2H, q), 2.64-2.12 (5H, m), 1.88-1.71
(2H, m), 1.58-1.15 (3H, s), 1.50-1.38 (15H, m), 1.32-1.23 (1H, m),
1.23-1.15 (3H s), 1.09-0.99 (3H, d)
[0140] Intermediate 2:
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcar-
bonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3oxo-androsta-1,4-diene-17.be-
ta.-carbothioic Acid S-fluoromethyl Ester Unsolvated Form 1
[0141] A mobile suspension of Intermediate 1 (12.61 g, 19.8 mmol)
in ethyl acetate (230 ml) and water (50 ml) is treated with a phase
transfer catalyst (benzyltributylammonium chloride, 10 mol %),
cooled to 3.degree. C. and treated with bromofluoromethane (1.10
ml, 19.5 mmol, 0.98 equivalents), washing in with prechilled
(0.degree. C.) ethyl acetate (EtOAc) (20 ml). The suspension is
stirred overnight, allowing to warm to 17.degree. C. The aqueous
layer is separated and the organic phase is sequentially washed
with 1M HCl (50 ml), 1% w/v NaHCO.sub.3 solution (3.times.50 ml)
and water (2.times.50 ml). The ethylacetate solution is distilled
at atmospheric pressure until the distillate reaches a temperature
of approximately 73.degree. C. at which point toluene (150 ml) is
added. Distillation is continued at atmospheric pressure until all
remaining EtOAc has been removed (approximate distillate
temperature 103.degree. C.). The resultant suspension is cooled and
aged at <10.degree. C. and filtered off. The bed is washed with
toluene (2.times.30 ml) and the product oven dried under vacuum at
60.degree. C. to constant weight to yield the title compound (8.77
g, 82%) LCMS retention time 3.66 min, m/z 539 MH.sup.+, NMR .delta.
(CDCl.sub.3) includes 7.60 (1H, m), 7.18-7.11 (2H, m), 6.52 (1H,
dd, J 4.2 Hz), 6.46 (1H, s), 6.41 (1H, dd, J 10, 2 Hz), 5.95 and
5.82 (2H dd, J 51, 9 Hz), 5.48 and 5.35 (1H, 2m), 4.48 (1H, m),
3.48 (1H, m), 1.55 (3H, s), 1.16 (3H, s), 1.06 (3H, d, J 7 Hz).
[0142] Intermediate 3:
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcar-
bonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-diene-17.b-
eta.-carbothioic Acid S-fluoromethyl Ester Unsolvated Form 1 in
Tetragonal Bipyramidal Habit
[0143] A sample of Intermediate 2 (1 wt) is suspended in a mixture
of propan-2-ol (2 vols), water (1 vol), ethyl acetate (13 vols).
The suspension is heated to reflux to give a solution. The solution
is clarified by passing a 5-micron line filter, following with a
line wash of ethyl acetate (2 vols). The solution is concentrated
to ca 10 vols via distillation at atmospheric pressure. Propan-2-ol
(10 vols) is added. The solution is seeded with the propan-2-ol
solvate of
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcarbonyl)oxy]-11.beta.-hy-
droxy-16.alpha.-methyl-3-oxo-androsta-1,4-diene-17.beta.-carbothioic
acid S-fluoromethyl ester (0.01 wt) suspended in propan-2-ol (ca
0.03 vols). The suspension is adjusted to 50+5.degree. and aged for
ca 5 mins (until crystallisation is established). The suspension is
concentrated once again to ca 10 vols. Further propan-2-ol (10
vols) is added and the suspension concentrated to ca 10 vols for a
third time (note: pot temp at this point ca80.degree.). The
suspension is cooled to 0-5.degree. C. over ca 120 mins and aged
for at least 60 mins. The white precipitate is isolated by vacuum
filtration washing the filter cake with chilled propan-2-ol and
dried in vacuo to afford the propan-2-ol solvate as an off-white to
grey solid.
[0144] Stoichiometry of compound of formula (I): propan-2-ol=1:1
from .sup.1H nmr (CDCl.sub.3)
[0145] The propan-2-ol is removed by the following process:
[0146] The product is heated under vacuum at 105 to 115.degree. C.
for at least 12 hours to give tetragonal bipyramidal particles of
unsolvated Form 1 of the active compound.
[0147] Pharmacological A
[0148] In Vitro Pharmacological Activity
[0149] Pharmacological activity was assessed in a functional in
vitro assay of glucocorticoid agonist activity which is generally
predictive of anti-inflammatory or anti-allergic activity in
vivo.
[0150] For the experiments in this section, compound of formula (I)
was used as unsolvated Form 1 (Intermediate 2)
[0151] The functional assay was based on that described by K. P.
Ray et al., Biochem J. (1997), 328, 707-715. A549 cells stably
transfected with a reporter gene containing the NF-.kappa.B
responsive elements from the ELAM gene promoter coupled to sPAP
(secreted alkaline phosphatase) were treated with test compounds at
appropriate doses for 1 hour at 37.degree. C. The cells were then
stimulated with tumour necrosis factor (TNF, 10 ng/ml) for 16
hours, at which time the amount of alkaline phosphatase produced is
measured by a standard colourimetric assay. Dose response curves
were constructed from which EC.sub.50 values were estimated.
[0152] In this test the compound of formula (I) showed an EC.sub.50
value of <1 nM.
[0153] The glucocorticoid receptor (GR) can function in at least
two distinct mechanisms, by upregulating gene expression through
the direct binding of GR to specific sequences in gene promotors,
and by downregulating gene expression that is being driven by other
transcription factors (such as NF.kappa.B or AP-1) through their
direct interaction with GR.
[0154] In a variant of the above method, to monitor these
functions, two reporter plasmids have been generated and introduced
separately into A549 human lung epithelial cells by transfection.
The first cell line contains the firefly luciferase reporter gene
under the control of a synthetic promoter that specifically
responds to activation of the transcription factor NF.kappa.B when
stimulated with TNF.alpha.. The second cell line contains the
renilla luciferase reporter gene under the control of a synthetic
promotor that comprises 3 copies of the consensus glucocorticoid
response element, and which responds to direct stimulation by
glucocorticoids. Simultaneous measurement of transactivation and
transrepression was conducted by mixing the two cell lines in a 1:1
ratio in 96 well plate (40,000 cells per well) and growing
overnight at 37.degree. C. Test compounds were dissolved in DMSO,
and added to the cells at a final DMSO concentration of 0.7%. After
incubation for 1 h 0.5 ng/ml TNF.alpha. (R&D Systems) was added
and after a further 15 hours at 37.degree. C., the levels of
firefly and renilla luciferase were measured using the Packard
Firelite kit following the manufacturers' directions. Dose response
curves were constructed from which EC.sub.50 values were
determined.
1 Transactivation (GR) Transrepression (NF.kappa.B) ED.sub.50 (nM)
ED.sub.50 (nM) Compound of Formula (I) 0.06 0.20 Metabolite (X)
>250 >1000 Fluticasone propionate 0.07 0.16
[0155] In Vivo Pharmacological Activity
[0156] Pharmacological activity in vivo was assessed in an
ovalbumin sensitised Brown Norway rat eosinophilia model. This
model is designed to mimic allergen induced lung eosinophilia, a
major component of lung inflammation in asthma.
[0157] For the experiments in this section, compound of formula (I)
was used as unsolvated Form 1.
[0158] Compound of formula (I) produced dose dependant inhibition
of lung eosinophilia in this model after dosing as an
intra-tracheal (IT) suspension in saline 30 min prior to ovalbumin
challenge. Significant inhibition is achieved after a single dose
of 30 .mu.g of compound of formula (I) and the response was
significantly (p=0.016) greater than that seen with an equivalent
dose of fluticasone propionate in the same study (69% inhibition
with compound of formula (I) vs 41% inhibition with fluticasone
propionate).
[0159] In a rat model of thymus involution 3 daily IT doses of 100
.mu.g of compound (I) induced significantly smaller reductions in
thymus weight (p=0.004) than an equivalent dose of fluticasone
propionate in the same study (67% reduction of thymus weight with
compound (I) vs 78% reduction with fluticasone propionate).
[0160] Taken together these results indicate a superior therapeutic
index for compound (I) compared to fluticasone propionate.
[0161] In vitro Metabolism in Rat and Human Hepatocytes
[0162] Incubation of compound (I) with rat or human hepatocytes
shows the compound to be metabolised in an identical manner to
fluticasone propionate with the 17-.beta. carboxylic add (X) being
the only significant metabolite produced. Investigation of the rate
of appearance of this metabolite on incubation of compound (I) with
human hepatocytes (37.degree. C., 10 .mu.M drug concentration,
hepatocytes from 3 subjects, 0.2 and 0.7 million cells/mL) shows
compound (I) to be metabolised ca. 5-fold more rapidly than
fluticasone propionate:-
2 17-.beta. acid metabolite production Subject Cell density
(pmol/h) number (million cells/mL) Compound (I) Fluticasone
propionate 1 0.2 48.9 18.8 1 0.7 73.3 35.4 2 0.2 118 9.7 2 0.7 903
23.7 3 0.2 102 6.6 3 0.7 580 23.9
[0163] Median metabolite production 102-118 pmol/h for compound (I)
and 18.8-23.0 pmol/h for fluticasone propionate.
[0164] Pharmacokinetics after Intravenous (IV) and Oral Dosing in
Rats
[0165] Compound (I) was dosed orally (0.1 mg/kg) and IV (0.1 mg/kg)
to male Wistar Han rats and pharmacokinetic parameters determined.
Compound (I) showed negligible oral bioavailability (0.90%) and
plasma clearance of 47.3 mL/min/kg, approaching liver blood flow
(plasma clearance of fluticasone propionate=45.2 mL/min/kg).
[0166] Pharmacokinetics after Intra-Tracheal Dry Powder Dosing in
the Pig.
[0167] Anaesthetised pigs (2) were dosed intra-tracheally with, a
homogenous mixture of compound (I) (1 mg) and fluticasone
propionate (1 mg) as a dry powder blend in lactose (10% w/w).
Serial blood samples were taken for up to 8h following dosing.
Plasma levels of compound (I) and fluticasone propionate were
determined following extraction and analysis using LC-MS/MS
methodology, the lower limits of quantitation of the methods were
10 and 20 pg/mL for compound (I) and fluticasone propionate
respectively. Using these methods compound (I) was quantifiable up
to 2 hours after dosing and fluficasone propionate was quantifiable
up to 8 hours after dosing. Maximum plasma concentrations were
observed for both compounds within 15 min after dosing. Plasma
half-life data obtained from IV dosing (0.1 mg/kg) was used to
calculate AUC (0-inf) values for compound (I). This compensates for
the plasma profile of Compound (I) only being defined up to 2 hours
after an IT dose and removes any bias due to limited data between
compound (I) and fluticasone propionate.
[0168] C.sub.max and AUC (0-info values show markedly reduced
systemic exposure to compound (I) compared to fluticasone
propionate:-
3 Cmax AUC (0-inf) (pg/mL) (hr .multidot. pg/mL) Pig 1 Pig 2 Pig 1
Pig 2 Compound of Formula (I) 117 81 254 221 Fluticasone propionate
277 218 455 495
[0169] The pharmacokinetic parameters for both compound (I) and
fluticasone propionate were the same in the anaesthetised pig
following intravenous administration of a mixture of the two
compounds at 0.1 mg/kg. The clearance of these two glucocorticoids
is similar is this experimental pig model.
EXAMPLES
Example 1
Nasal Formulation Containing
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-fura-
nylcarbonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-dien-
e-17.beta.-carbothioic Acid S-fluoromethyl Ester
[0170]
4 A formulation for intranasal delivery was prepared with
ingredients as follows:
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcarbonyl)oxy]-
0.05% w/w 11.beta.-hydroxy-16.alpha.-methyl-3-oxo-
androsta-1,4-diene-17.beta.-carbothioic acid S-fluoromethyl ester
(prepared according to Intermediate 3, micronised to MMD 3 .mu.m)
Polysorbate 80 0.025% w/w Avicel RC591 1.5% w/w Dextrose 5.0% w/w
BKC 0.015% w/w EDTA 0.015% w/w water to 100%
[0171] in a total amount suitable for 120 actuations and the
formulation was filled into a bottle (plastic or glass) fitted with
a suitable pre-compression pump and nasal actuator, adapted to
dispense 50 or 100 .mu.l per actuation, preferably 50 .mu.l
[0172] The formulation was prepared following the following
protocol:
[0173] Part A
[0174] 1. Dissolve dextrose in purified water
[0175] 2. Dissolve EDTA in dextrose solution
[0176] 3. Add Avicel RC591 while stirring
[0177] 4. Allow suspension to hydrate
[0178] Part B (separately)
[0179] 1. Dissolve polysorbate 80 in purified water at 50-60
.degree. C.
[0180] 2. Prepare slurry of drug in Polysorbate 80 solution
[0181] Part C
[0182] 1. Combine suspension of A4 with suspension of B2 and
stir
[0183] 2. Add solution of BKC in purifed water and stir
[0184] 3. Adjust pH with 1N HCl
[0185] 4. Add purified water to correct weight
Example 2
Nasal Formulation Containing
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-fura-
nylcarbonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-dien-
e-17.beta.-carbothioic Acid S-fluoromethyl Ester
[0186]
5 A formulation for intranasal delivery was prepared with
ingredients as follows:
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-furanylcarbonyl)oxy]- 0.1%
w/w 11.beta.-hydroxy-16.alpha.-methyl-3-oxo-
androsta-1,4-diene-17.beta.-carbothioic acid S-fluoromethyl ester
(prepared according to Intermediate 3, micronised to MMD 3 .mu.m)
Polysorbate 80 0.025% w/w Avicel RC591 1.5% w/w Dextrose 5.0% w/w
BKC 0.015% w/w EDTA 0.015% w/w water to 100%
[0187] in a total amount suitable for 120 actuations and the
formulation was filled into a bottle (plastic or glass) fitted with
a suitable pre-compression pump and nasal actuator, adapted to
dispense 50 or 100 .mu.l per actuation, preferably 50 .mu.l.
Example 3
Nasal Formulation Containing
6.alpha.,9.alpha.-Difluoro-17.alpha.-[(2-fura-
nylcarbonyl)oxy]-11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-dien-
e-17.beta.carbothioic Acid S-fluoromethyl Ester
[0188]
6 A formulation for intranasal delivery was prepared with
ingredients as follows:
6.alpha.,9.alpha.-Difluoro-17.alpha.-1[(2-furanylcarbonyl)oxy]-
0.1% w/w 11.beta.-hydroxy-16.alpha.-methyl-3-oxo-androsta-1,4-
diene-17.beta.-carbothioic acid S-fluoromethyl ester (prepared
according to intermediate 3, micronised to MMD, 1.5 .mu.m)
Polysorbate 80 0.025% w/w Avicel RC591 1.5% w/w Dextrose 5.0% w/w
BKC 0.015% w/w EDTA 0.015% Water to 100%
[0189] in a total amount suitable for 120 actuations and the
formulation was filled into a bottle (plastic or glass) fitted with
a suitable pre-compression pump and nasal actuator, adapted to
dispense 50 or 100 .mu.l per actuation. Preferably 50 .mu.l.
[0190] The formulation was prepared following the different
protocol below:
[0191] Part A
[0192] 5. Dissolve dextrose in purified water
[0193] 6. Dissolve EDTA in dextrose solution
[0194] 7. Add Avicel RC591 while stirring
[0195] 8. Allow suspension to hydrate
[0196] Part B (separately)
[0197] 3. Dissolve polysorbate 80 in purified water at
50-60.degree. C.
[0198] 4. Prepare slurry of drug in polysorbate 80 solution using a
suitable micronfluidizer, e.g. Microfluidics 110S, ensuring
suitable processing to attain target MMD of ,1.5 .mu.m
[0199] Part C
[0200] 5. Combine suspension of A4 with suspension of B2 and
stir
[0201] 6. Add solution of BKC in purified water and stir
[0202] 7. Adjust pH with 1N HCl
[0203] 8. Add purified water to correct weight.
[0204] Stability studies on Example 3 showed it to be stable up to
3 months at 40.degree. C. (measurements were not taken beyond this
time). The particle size of the active material has also been
observed not to change significantly.
[0205] The device of the invention will now be described, by way of
example only, with reference to the accompanying drawing in
which:
[0206] FIG. 1 shows an exploded view of a nasal inhaler suitable
for use in accord with the invention;
[0207] With reference to FIG. 1, there is shown a nasal inhaler
device 5 comprising a body 6 a container 3 and a nasal pump 8. The
device further comprises a protective end cap 7 having an inner
surface 4 for engagement with the body 6 to protect the dispensing
nozzle 11.
[0208] The body 6 is made from a plastic material and defines a
housing 9 and a dispensing nozzle 11. The housing 9 defines a
cavity formed by a side wall and a first end wall and a second end
wall 14. The dispensing nozzle 11 is connected to and extends away
from the second end wall 14 and has an external tapering form.
[0209] The dispensing nozzle 11 has a longitudinally extending
orifice defined by an outlet tube extending towards the cavity 10.
An annular abutment is formed within the orifice part way along the
outlet tube. The annular abutment defines a small aperture through
which fluid can flow in use.
[0210] The nasal pump 8 comprises a hollow casing 30 defining a
reservoir containing several doses of the fluid nasal formulation
to be dispensed and a plunger slidably engaged within the hollow
casing 30. One detailed example of a suitable nasal pump Is
described in U.S. Pat. No. 4,964,069 incorporated herein by
reference.
[0211] Throughout the specification and the claims which follow,
unless the context requires otherwise, the word `comprise`, and
variations such as `comprises` and `comprising`, will be understood
to imply the inclusion of a stated integer or step or group of
integers but not to the exclusion of any other integer or step or
group of integers or steps.
[0212] The patents and patent applications described in this
application are herein incorporated by reference.
* * * * *