U.S. patent application number 14/430179 was filed with the patent office on 2015-10-01 for systems for treating pulmonary infections.
The applicant listed for this patent is INSMED INCORPORATED. Invention is credited to Michael Hahn, Philipp Holzmann, Xingong Li, Vladimir Malinin, Brian Miller, Walter Perkins, Harald Schulz, Dominique Seidel.
Application Number | 20150272880 14/430179 |
Document ID | / |
Family ID | 49624305 |
Filed Date | 2015-10-01 |
United States Patent
Application |
20150272880 |
Kind Code |
A1 |
Seidel; Dominique ; et
al. |
October 1, 2015 |
SYSTEMS FOR TREATING PULMONARY INFECTIONS
Abstract
Provided herein are systems for treating a subject with a
pulmonary infection, for example, a nontuberculous mycobacterial
pulmonary infection, a Burkholderia pulmonary infection, a
pulmonary infection associated with bronchiectasis, or a
Pseudomonas pulmonary infection. The system includes a
pharmaceutical formulation comprising a liposomal aminoglycoside
dispersion, and the lipid component of the liposomes consist
essentially of electrically neutral lipids. The system also
includes a nebulizer which generates an aerosol of the
pharmaceutical formulation at a rate greater than about 0.53 gram
per minute. The aerosol is delivered to the subject via inhalation
for the treatment of the pulmonary infection.
Inventors: |
Seidel; Dominique; (Munchen,
DE) ; Holzmann; Philipp; (Munchen, DE) ;
Schulz; Harald; (Tuttlingen, DE) ; Hahn; Michael;
(Krailing, DE) ; Perkins; Walter; (Pennington,
NJ) ; Malinin; Vladimir; (Plainsboro, NJ) ;
Li; Xingong; (Robbinsville, NJ) ; Miller; Brian;
(Hamilton, NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
INSMED INCORPORATED |
Bridgewater |
NJ |
US |
|
|
Family ID: |
49624305 |
Appl. No.: |
14/430179 |
Filed: |
May 21, 2013 |
PCT Filed: |
May 21, 2013 |
PCT NO: |
PCT/US13/42113 |
371 Date: |
March 20, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61649830 |
May 21, 2012 |
|
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|
Current U.S.
Class: |
424/450 ;
128/200.23; 514/40 |
Current CPC
Class: |
A61P 31/00 20180101;
A61K 9/0078 20130101; A61P 31/04 20180101; A61K 9/127 20130101;
A61K 31/7036 20130101; A61P 31/06 20180101; A61K 9/1271 20130101;
A61M 11/005 20130101; A61M 11/02 20130101; A61P 11/00 20180101 |
International
Class: |
A61K 9/00 20060101
A61K009/00; A61M 11/00 20060101 A61M011/00; A61M 11/02 20060101
A61M011/02; A61K 31/7036 20060101 A61K031/7036; A61K 9/127 20060101
A61K009/127 |
Claims
1. A system for treating or providing prophylaxis against a
pulmonary infection in a patient, comprising: (a) a pharmaceutical
formulation comprising an aqueous dispersion of liposomal complexed
aminoglycoside, wherein the lipid component of the liposome
consists of electrically neutral lipids, and (b) a nebulizer which
generates an aerosol of the pharmaceutical formulation at a rate
greater than about 0.53 g per minute, wherein the mass median
aerodynamic diameter (MMAD) of the aerosol is less than about 4.2
.mu.m, as measured by the Anderson Cascade Impactor (ACI), or less
than about 4.9 .mu.m, as measured by the Next Generation Impactor
(NGI).
2. (canceled)
3. The system of claim 1, wherein the aminoglycoside is selected
from amikacin, apramycin, arbekacin, astromicin, capreomycin,
dibekacin, framycetin, gentamicin, hygromycin B, isepamicin,
kanamycin, neomycin, netilmicin, paromomycin, rhodestreptomycin,
ribostamycin, sisomicin, spectinomycin, streptomycin, tobramycin,
verdamicin, or a combination thereof.
4. The system of claim 1, wherein the aminoglycoside is
amikacin.
5. The system of claim 1, wherein the aminoglycoside is amikacin
sulfate.
6. The system of claim 1, wherein the liposome comprises
unilamellar vesicles, multilamellar vesicles, or a mixture
thereof.
7. The system of claim 1, wherein the electrically neutral lipids
comprise an electrically neutral phospholipid or an electrically
neutral phospholipid and a sterol.
8. The system of claim 1, wherein the electrically neutral lipids
comprise a phosphatidylcholine and a sterol.
9. The system of claim 1, wherein the electrically neutral lipids
comprise dipalmitoylphosphatidylcholine (DPPC) and a sterol.
10. The system of claim 1, wherein the electrically neutral lipids
comprise DPPC and cholesterol.
11. The system of claim 1, wherein the aminoglycoside is amikacin,
the electrically neutral lipids consist of DPPC and cholesterol,
and the liposome comprises unilamellar vesicles, multilamellar
vesicles, or a mixture thereof.
12.-13. (canceled)
14. The system of claim 1, wherein the ratio by weight of free
aminoglycoside to the liposomal complexed aminoglycoside is from
about 0.3:1 to about 2:1.
15. The system of claim 1, wherein the volume of pharmaceutical
formulation is about 8 mL.
16. The system of claim 1, wherein the aerosol of the
pharmaceutical formulation comprises about 55% to about 75%
liposomal complexed amikacin.
17. The system of claim 1, wherein the liposomal complexed
aminoglycoside has an MMAD of about 3.2 .mu.m to about 4.2 .mu.m,
as measured by the ACI; or about 4.4 .mu.m to about 4.9 .mu.m, as
measured by the NGI.
18. The system of claim 1, wherein the liposomal complexed
aminoglycoside has an MMAD of about 3.6 .mu.m to about 3.9 .mu.m,
as measured by the ACI; or about 4.5 .mu.m to about 4.8 .mu.m, as
measured by the NGI.
19.-29. (canceled)
30. A method for treating or providing prophylaxis against a
pulmonary infection in a patient, the method comprising:
aerosolizing a pharmaceutical formulation comprising an aqueous
dispersion of liposomal complexed aminoglycoside, wherein the lipid
component of the liposome consists of electrically neutral lipids,
at a rate greater than about 0.53 gram per minute, and
administering the aerosolized pharmaceutical formulation to the
lungs of the patient; wherein the aerosolized pharmaceutical
formulation comprises a mixture of free aminoglycoside and
liposomal complexed aminoglycoside, and the MMAD of the aerosol is
less than about 4.2 .mu.m, as measured by the ACI, or less than
about 4.9 .mu.m, as measured by the NGI.
31. The method of claim 30, wherein, the MMAD of the aerosol is
about 3.2 .mu.m to about 4.2 .mu.m, as measured by the ACI, or
about 4.4 .mu.m to about 4.9 .mu.m, as measured by the NGI.
32.-40. (canceled)
41. The method of claim 30, wherein the aerosolized pharmaceutical
formulation is administered once per day in a single dosing
session.
42. The method of claim 30, wherein the aminoglycoside is
amikacin.
43. The method of claim 30, wherein the aminoglycoside is amikacin
sulfate.
44.-97. (canceled)
98. The method of claim 30, wherein the patient has cystic
fibrosis.
99. The method of claim 30, wherein the pulmonary infection is a
nontuberculous mycobacterial infection.
100. The method of claim 30, wherein the pulmonary infection is a
Pseudomonas aeruginosa infection.
101. The method of claim 30, wherein the pulmonary infection is a
mycobacterial infection.
102.-146. (canceled)
147. The method of claim 30, wherein the aminoglycoside is
amikacin, apramycin, arbekacin, astromicin, capreomycin, dibekacin,
framycetin, gentamicin, hygromycin B, isepamicin, kanamycin,
neomycin, netilmicin, paromomycin, rhodestreptomycin, ribostamycin,
sisomicin, spectinomycin, streptomycin, tobramycin or
verdamicin.
148. The method of claim 101, wherein the mycobacterial infection
is M. abscessus, M. chelonae, M. bolletii, M tuberculosis, M avium
complex (MAC), (M avium and M intracellulare), M. kansasii, M
xenopi, M marinum, M ulcerans or M. fortuitum complex (M. fortuitum
and M. chelonae).
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority from U.S.
Provisional Application No. 61/649,830, filed May 21, 2012, hereby
incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] Certain technologies suitable for administration by
inhalation employ liposomes and lipid complexes supply a prolonged
therapeutic effect of drug in the lung. These technologies also
provide the drug with sustained activities, and the ability to
target and enhance the uptake of the drug into sites of
disease.
[0003] Inhalation delivery of liposomes is complicated by their
sensitivity to shear-induced stress during nebulization, which can
lead to change in physical characteristics (e.g., entrapment,
size). However, as long as the changes in characteristics are
reproducible and meet acceptability criteria, they need not be
prohibitive to pharmaceutical development.
[0004] Cystic fibrosis (CF) patients have thick mucus and/or sputum
secretions in the lungs, frequent consequential infections, and
biofilms resulting from bacterial colonizations. All these fluids
and materials create barriers to effectively targeting infections
with aminoglycosides. Liposomal aminoglycoside formulations may be
useful in combating the bacterial biofilms.
SUMMARY OF THE INVENTION
[0005] The present invention provides methods for treating various
pulmonary infections, including mycobacterial infections (e.g.,
pulmonary infections caused by nontuberculous mycobacterium, also
referred to herein as nontuberculous mycobacterial (NTM)
infections), by providing systems for delivery of aerosolized
liposomal formulations via inhalation. For example, the systems and
methods provided herein can be used to treat a pulmonary
nontuberculous mycobacterial infection such as pulmonary M. avium,
M avium subsp. hominissuis (MAH), M. abscessus, M chelonae, M.
bolletii, M. kansasii, M ulcerans, M avium, M avium complex (MAC)
(M. avium and M. intracellulare), M conspicuum, M. kansasii, M.
peregrinum, M. immunogenum, M. xenopi, M. marinum, M. malmoense, M
marinum, M. mucogenicum, M. nonchromogenicum, M scrofulaceum, M
simiae, M smegmatis, M. szulgai, M terrae, M terrae complex, M
haemophilum, M. genavense, M gordonae, M. ulcerans, M. fortuitum or
M. fortuitum complex (M. fortuitum and M. chelonae) infection.
[0006] In one aspect, the present invention provides a system for
treating or providing prophylaxis against a pulmonary infection. In
one embodiment, the system comprises a pharmaceutical formulation
comprising a liposomal complexed aminoglycoside, wherein the
formulation is a dispersion (e.g., a liposomal solution or
suspension), the lipid component of the liposome consists of
electrically neutral lipids, and a nebulizer which generates an
aerosol of the pharmaceutical formulation at a rate greater than
about 0.53 g per minute. In one embodiment, the mass median
aerodynamic diameter (MMAD) of the aerosol is less than about 4.2
.mu.m, as measured by the Anderson Cascade Impactor (ACI), about
3.2 .mu.m to about 4.2 .mu.m, as measured by the ACI, or less than
about 4.9 .mu.m, as measured by the Next Generation Impactor (NGI),
or about 4.4 .mu.m to about 4.9 .mu.m, as measured by the NGI.
[0007] In another embodiment, the system for treating or providing
prophylaxis against a pulmonary infection comprises a
pharmaceutical formulation comprising a liposomal complexed
aminoglycoside, wherein the formulation is a dispersion (e.g., a
liposomal solution or suspension), the lipid component of the
liposome consists of electrically neutral lipids, and a nebulizer
which generates an aerosol of the pharmaceutical formulation at a
rate greater than about 0.53 g per minute. The fine particle
fraction (FPF) of the aerosol is greater than or equal to about
64%, as measured by the Anderson Cascade Impactor (ACI), or greater
than or equal to about 51%, as measured by the Next Generation
Impactor (NGI).
[0008] In one embodiment, the system provided herein comprises a
pharmaceutical formulation comprising an aminoglycoside. In a
further embodiment, the aminoglycoside is amikacin, apramycin,
arbekacin, astromicin, capreomycin, dibekacin, framycetin,
gentamicin, hygromycin B, isepamicin, kanamycin, neomycin,
netilmicin, paromomycin, rhodestreptomycin, ribostamycin,
sisomicin, spectinomycin, streptomycin, tobramycin, verdamicin or a
combination thereof. In even a further embodiment, the
aminoglycoside is amikacin. In another embodiment, the
aminoglycoside is selected from an aminoglycoside set forth in
Table A, below, or a combination thereof.
TABLE-US-00001 TABLE A AC4437 dibekacin K-4619 sisomicin amikacin
dactimicin isepamicin rhodestreptomycin apramycin etimicin KA-5685
sorbistin arbekacin framycetin kanamycin spectinomycin astromicin
gentamicin neomycin sporaricin bekanamycin H107 netilmicin
streptomycin boholmycin hygromycin paromomycin tobramycin
brulamycin hygromycin B plazomicin verdamicin capreomycin
inosamycin ribostamycin vertilmicin
[0009] The pharmaceutical formulations provided herein are
dispersions of liposomes (i.e., liposomal dispersions or aqueous
liposomal dispersions which can be either liposomal solutions or
liposomal suspensions). In one embodiment, the lipid component of
the liposomes consists essentially of one or more electrically
neutral lipids. In a further embodiment, the electrically neutral
lipid comprises a phospholipid and a sterol. In a further
embodiment, the phospholipid is dipalmitoylphosphatidylcholine
(DPPC) and the sterol is cholesterol.
[0010] In one embodiment, the lipid to drug ratio in the
aminoglycoside pharmaceutical formulation (aminoglycoside liposomal
solution or suspension) is about 2:1, about 2:1 or less, about 1:1,
about 1:1 or less, or about 0.7:1.
[0011] In one embodiment, the aerosolized aminoglycoside
formulation, upon nebulization, has an aerosol droplet size of
about 1 .mu.m to about 3.8 .mu.m, about 1.0 .mu.m to 4.8 .mu.m,
about 3.8 .mu.am to about 4.8 .mu.m, or about 4.0 .mu.m to about
4.5 .mu.m. In a further embodiment, the aminoglycoside is amikacin.
In even a further embodiment, the amikacin is amikacin sulfate.
[0012] In one embodiment, about 70% to about 100% of the
aminoglycoside present in the formulation is liposomal complexed,
e.g., encapsulated in a plurality of liposomes, prior to
nebulization. In a further embodiment, the aminoglycoside is
selected from an aminoglycoside provided in Table A. In further
embodiment, the aminoglycoside is an amikacin. In even a further
embodiment, about 80% to about 100% of the amikacin is liposomal
complexed, or about 80% to about 100% of the amikacin is
encapsulated in a plurality of liposomes. In another embodiment,
prior to nebulization, about 80% to about 100%, about 80% to about
99%, about 90% to about 100%, 90% to about 99%, or about 95% to
about 99% of the aminoglycoside present in the formulation is
liposomal complexed prior to nebulization.
[0013] In one embodiment, the percent liposomal complexed (also
referred to herein as "liposomal associated") aminoglycoside
post-nebulization is from about 50% to about 80%, from about 50% to
about 75%, from about 50% to about 70%, from about 55% to about
75%, or from about 60% to about 70%. In a further embodiment, the
aminoglycoside is selected from an aminoglycoside provided in Table
A. In a further embodiment, the aminoglycoside is amikacin. In even
a further embodiment, the amikacin is amikacin sulfate.
[0014] In another aspect, the present invention provides methods
for treating or providing prophylaxis against a pulmonary
infection. In one embodiment, the pulmonary infection is a
pulmonary infection caused by a gram negative bacterium (also
referred to herein as a gram negative bacterial infection). In one
embodiment, the pulmonary infection is a Pseudomonas infection,
e.g., a Pseudomonas aeruginosa infection. In another embodiment,
the pulmonary infection is caused by one of the Pseudomonas species
provided in Table B, below. In one embodiment, a patient is treated
for mycobacterial lung infection with one of the systems provided
herein. In a further embodiment, the mycobacterial pulmonary
infection is a nontuberculous mycobacterial pulmonary infection, a
Mycobacterium abscessus pulmonary infection or a Mycobacterium
avium complex pulmonary infection. In one or more of the preceding
embodiments, the patient is a cystic fibrosis patient.
[0015] In one embodiment, a patient with cystic fibrosis is treated
for a pulmonary infection with one of the systems provided herein.
In a further embodiment, the pulmonary infection is caused by
Mycobacterium abscessus, Mycobacterium avium complex, or P.
aeruginosa. In another embodiment, the pulmonary infection is
caused by a nontuberculous mycobacterium selected from M. avium, M
avium subsp. hominissuis (MAH), M. abscessus, M chelonae, M.
bolletii, M. kansasii, M ulcerans, M avium, M. avium complex (MAC)
(M. avium and M. intracellulare), M. conspicuum, M. kansasii, M.
peregrinum, M. immunogenum, M. xenopi, M marinum, M. malmoense, M
marinum, M mucogenicum, M nonchromogenicum, M. scrofulaceum, M
simiae, M smegmatis, M szulgai, M. terrae, M terrae complex, M
haemophilum, M. genavense, M. asiaticum, M shimoidei, M gordonae,
M. nonchromogenicum, M triplex, M lentiflavum, M. celatum, M
fortuitum, M. fortuitum complex (M. fortuitum and M. chelonae) or a
combination thereof.
[0016] In another aspect, a method for treating or providing
prophylaxis against a pulmonary infection in a patient is provided.
In one embodiment, the method comprises aerosolizing a
pharmaceutical formulation comprising a liposomal complexed
aminoglycoside, wherein the pharmaceutical formulation is an
aqueous dispersion of liposomes (e.g., a liposomal solution or
liposomal suspension), and is aerosolized at a rate greater than
about 0.53 gram per minute. The method further comprises
administering the aerosolized pharmaceutical formulation to the
lungs of the patient; wherein the aerosolized pharmaceutical
formulation comprises a mixture of free aminoglycoside and
liposomal complexed aminoglycoside, and the lipid component of the
liposome consists of electrically neutral lipids. In a further
embodiment, the mass median aerodynamic diameter (MMAD) of the
aerosol is about 1.0 .mu.m to about 4.2 .mu.m as measured by the
ACI. In any one of the proceeding embodiments, the MMAD of the
aerosol is about 3.2 .mu.m to about 4.2 .mu.m as measured by the
ACI. In any one of the proceeding embodiments, the MMAD of the
aerosol is about 1.0 .mu.m to about 4.9 .mu.m as measured by the
NGI. In any one of the proceeding embodiments, the MMAD of the
aerosol is about 4.4 .mu.m to about 4.9 .mu.m as measured by the
NGI.
[0017] In one embodiment, the method comprises aerosolizing a
pharmaceutical formulation comprising a liposomal complexed
aminoglycoside, wherein the pharmaceutical formulation is an
aqueous dispersion and is aerosolized at a rate greater than about
0.53 gram per minute. The method further comprises administering
the aerosolized pharmaceutical formulation to the lungs of the
patient; wherein the aerosolized pharmaceutical formulation
comprises a mixture of free aminoglycoside and liposomal complexed
aminoglycoside (e.g., aminoglycoside encapsulated in a liposome),
and the liposome component of the formulation consists of
electrically neutral lipids. In even a further embodiment, fine
particle fraction (FPF) of the aerosol is greater than or equal to
about 64%, as measured by the ACI, or greater than or equal to
about 51%, as measured by the NGI.
[0018] In another aspect, a liposomal complexed aminoglycoside
aerosol (e.g., a liposomal complexed aminoglycoside) is provided.
In one embodiment, the aerosol comprises an aminoglycoside and a
plurality of liposomes comprising DPPC and cholesterol, wherein
about 65% to about 75% of the aminoglycoside is liposomal complexed
and the aerosol is generated at a rate greater than about 0.53 gram
per minute. In a further embodiment, about 65% to about 75% of the
aminoglycoside is liposomal complexed, and the aerosol is generated
at a rate greater than about 0.53 gram per minute. In any one of
the proceeding embodiments, the aerosol is generated at a rate
greater than about 0.54 gram per minute. In any one of the
proceeding embodiments, the aerosol is generated at a rate greater
than about 0.55 gram per minute. In any one of the preceding
embodiments, the aminoglycoside is selected from an aminoglycoside
provided in Table A.
[0019] In one embodiment, the MMAD of the liposomal complexed
aminoglycoside aerosol is about 3.2 .mu.m to about 4.2 .mu.am, as
measured by the ACI, or about 4.4 .mu.m to about 4.9 .mu.m, as
measured by the NGI. In a further embodiment, the aerosol comprises
an aminoglycoside and a plurality of liposomes comprising DPPC and
cholesterol, wherein about 65% to about 75% of the aminoglycoside
is liposomal complexed (e.g., encapsulated in the plurality of the
liposomes), and the liposomal aminoglycoside aerosol is generated
at a rate greater than about 0.53 gram per minute. In a further
embodiment, the aminoglycoside is selected from an aminoglycoside
provided in Table A.
[0020] In one embodiment, the FPF of the lipid-complexed
aminoglycoside aerosol is greater than or equal to about 64%, as
measured by the Anderson Cascade Impactor (ACI), or greater than or
equal to about 51%, as measured by the Next Generation Impactor
(NGI). In a further embodiment, the aerosol comprises an
aminoglycoside and a plurality of liposomes comprising DPPC and
cholesterol, wherein about 65% to about 75% of the aminoglycoside
is liposomal complexed, for example, encapsulated in the plurality
of the liposomes, and the liposomal aminoglycoside aerosol is
generated at a rate greater than about 0.53 gram per minute. In any
one of the proceeding embodiments, the aerosol is generated at a
rate greater than about 0.54 gram per minute. In any one of the
proceeding embodiments, the aerosol is generated at a rate or
greater than about 0.55 gram per minute. In any of the preceding
embodiments, the aminoglycoside is selected from an aminoglycoside
provided in Table A.
[0021] In one embodiment, the aerosol comprises an aminoglycoside
and a plurality of liposomes comprising DPPC and cholesterol,
wherein about 65% to about 75% of the aminoglycoside is liposomal
complexed. In a further embodiment, about 65% to about 75% of the
aminoglycoside is encapsulated in the plurality of liposomes. In a
further embodiment, the aerosol is generated at a rate greater than
about 0.53 gram per minute, greater than about 0.54 gram per
minute, or greater than about 0.55 gram per minute. In a further
embodiment, the aminoglycoside is amikacin (e.g., amikacin
sulfate).
[0022] In one embodiment, the concentration of the aminoglycoside
in the liposomal complexed aminoglycoside is about 50 mg/mL or
greater. In a further embodiment, the concentration of the
aminoglycoside in the liposomal complexed aminoglycoside is about
60 mg/mL or greater. In a further embodiment, the concentration of
the aminoglycoside in the liposomal complexed aminoglycoside is
about 70 mg/mL or greater, for example about 70 mg/mL to about 75
mg/mL. In a further embodiment, the aminoglycoside is selected from
an aminoglycoside provided in Table A. In even a further
embodiment, the aminoglycoside is amikacin (e.g., amikacin
sulfate).
BRIEF DESCRIPTION OF THE FIGURES
[0023] FIG. 1 shows a diagram of a nebulizer (aerosol generator) in
which the present invention may be implemented.
[0024] FIG. 2 is an enlarged representation of the nebulizer
diagram shown in FIG. 1.
[0025] FIG. 3 shows a cross-sectional view of a generally known
aerosol generator, as described in WO 2001/032246.
[0026] FIG. 4 is an image of a PARI eFlow.RTM. nebulizer, modified
for use with the aminoglycoside formulations described herein, and
a blown up diagram of the nebulizer's membrane.
[0027] FIG. 5 is a cross-sectional computed tomography (CT) image
showing a membrane having a relatively long nozzle portion.
[0028] FIG. 6 is a cross-sectional computed tomography (CT) image
of a stainless steel membrane having a relatively short nozzle
portion.
[0029] FIG. 7 is a cross sectional cartoon depiction of the
sputum/biofilm seen, for example, in patients with cystic
fibrosis.
[0030] FIG. 8 is a graph of the time period of aerosol generation
upon complete emission of the liquid within the liquid reservoir
(Nebulization time) as a function of the initial gas cushion within
the liquid reservoir (V.sub.A).
[0031] FIG. 9 is a graph of negative pressure in the nebulizer as a
function of the time of aerosol generation until complete emission
of the pharmaceutical formulation from the liquid reservoir
(nebulization time).
[0032] FIG. 10 is a graph of aerosol generation efficiency as a
function of the negative pressure in the nebulizer.
[0033] FIG. 11 is a graph of the period of time for aerosol
generation upon complete emission of the liquid (nebulization time)
as a function of the ratio between the increased volume V.sub.RN of
the liquid reservoir and the initial volume of liquid within the
liquid reservoir (V.sub.L) (V.sub.RN V.sub.L).
[0034] FIG. 12 is a graph showing the MMAD of aerosolized
formulations as a function of nebulization rate of the respective
formulation.
[0035] FIG. 13 is a graph showing the FPF of aerosolized
formulations as a function of the nebulization rate of the
respective formulation.
[0036] FIG. 14 is a schematic of the system used for the recovery
of aerosol for post-nebulization studies.
DETAILED DESCRIPTION OF THE INVENTION
[0037] The invention described herein is directed, in part, to
systems for administering an aminoglycoside pharmaceutical
formulation to the lungs of a subject, for example, to treat a
pulmonary disorder.
[0038] The term "treating" includes: (1) preventing or delaying the
appearance of clinical symptoms of the state, disorder or condition
developing in the subject that may be afflicted with or predisposed
to the state, disorder or condition but does not yet experience or
display clinical or subclinical symptoms of the state, disorder or
condition; (2) inhibiting the state, disorder or condition (i.e.,
arresting, reducing or delaying the development of the disease, or
a relapse thereof in case of maintenance treatment, of at least one
clinical or subclinical symptom thereof); and/or (3) relieving the
condition (i.e., causing regression of the state, disorder or
condition or at least one of its clinical or subclinical symptoms).
The benefit to a subject to be treated is either statistically
significant or at least perceptible to the subject or to the
physician.
[0039] In one embodiment, pulmonary infections caused by the
following bacteria are treatable with the systems and formulations
provided herein: Pseudomonas (e.g., P. aeruginosa, P. paucimobilis,
P. putida, P. fluorescens, and P. acidovorans), Burkholderia (e.g.,
B. pseudomallei, B. cepacia, B. cepacia complex, B. dolosa, B.
fungorum, B. gladioli, B. multivorans, B. vietnamiensis, B.
pseudomallei, B. ambifaria, B. andropogonis, B. anthina, B.
brasilensis, B. caledonica, B. caribensis, B. caryophylli),
Staphylococcus (e.g., S. aureus, S. auricularis, S. carnosus, S.
epidermidis, S. lugdunensis), Methicillin-resistant Staphylococcus
aureus (MRSA), Streptococcus (e.g., Streptococcus pneumoniae),
Escherichia coli, Klebsiella, Enterobacter, Serratia, Haemophilus,
Yersinia pestis, Mycobacterium (e.g., nontuberculous
mycobacterium).
[0040] In one embodiment, a patient is treated for a nontuberculous
mycobacterial lung infection with one of the systems provided
herein. In a further embodiment, the nontuberculous mycobacterial
lung infection is a recalcitrant nontuberculous mycobacterial lung
infection.
[0041] In one embodiment, the systems provided herein are used to
treat a patient having a pulmonary infection caused by Pseudomonas.
In a further embodiment, the pulmonary infection is caused by a
Pseudomonas species selected from a species provided in Table B,
below.
TABLE-US-00002 TABLE B P. abietaniphila P. aeruginosa P. agarici P.
alcaligenes P. alcaliphila P. amygdale P. anguilliseptica P.
antarctica P. argentinensis P. asplenii P. aurantiaca P.
aureofaciens P. avellanae P. azotifigens P. azotoformans P.
balearica P. borbori P. brassicacearum P. brenneri P. cannabina P.
caricapapayae P. cedrina P. chlororaphis P. cichorii P.
citronellolis P. coenobios P. congelans P. coronofaciens P.
corrugate P. costantinii P. cremoricolorata P. cruciviae P.
delhiensis P. denitrificans P. excibis P. extremorientalis P.
ficuseructae P. flavescens P. fluorescens P. fragi P.
frederiksbergensis P. fulva P. fuscovaginae P. gelidicola P.
gessardii P. grimontii P. indica P. jessenii P. jinjuensis P.
kilonensis P. knackmussii P. koreensis P. libanensis P. lini P.
lundensis P. lutea P. luteola P. mandelii P. marginalis P.
mediterranea
TABLE-US-00003 TABLE B P. meliae P. mendocina P. meridiana P.
migulae P. monteilii P. moraviensis P. mosselii P. mucidolens P.
nitroreducens P. oleovorans P. orientalis P. oryzihabitans P.
otitidis P. pachastrellae P. palleroniana P. panacis P. papaveris
P. parafulva P. peli P. perolens P. pertucinogena P.
plecoglossicida P. poae P. pohangensis P. proteolytica P.
pseudoalcaligenes P. psychrophila P. psychrotolerans P. putida P.
rathonis P. reptilivora P. resiniphila P. resinovorans P.
rhizosphaerae P. rhodesiae P. rubescens P. salomonii P. savastanoi
P. segitis P. septic P. simiae P. straminea P. stutzeri P. suis P.
synxantha P. syringae P. taetrolens P. thermotolerans P.
thivervalensis P. tolaasii P. tremae P. trivialis P. turbinellae P.
tuticorinensis P. umsongensis P. vancouverensis P. veronii P.
viridiflava P. vranovensis P. xanthomarina
[0042] The nontuberculous mycobacterial lung infection, in one
embodiment, is selected from M avium, M. avium subsp. hominissuis
(MAH), M. abscessus, M. chelonae, M. bolletii, M. kansasii, M
ulcerans, M avium, M. avium complex (MAC) (M. avium and M
intracellulare), M. conspicuum, M. kansasii, M. peregrinum, M.
immunogenum, M. xenopi, M marinum, M. malmoense, M marinum, M
mucogenicum, M nonchromogenicum, M. scrofulaceum, M simiae, M
smegmatis, M szulgai, M. terrae, M terrae complex, M haemophilum,
M. genavense, M. asiaticum, M shimoidei, M gordonae, M.
nonchromogenicum, M triplex, M lentiflavum, M. celatum, M
fortuitum, M. fortuitum complex (M. fortuitum and M. chelonae) or a
combination thereof. In a further embodiment, the nontuberculous
mycobacterial lung infection is M. abscessus or M. avium. In a
further embodiment, the M avium infection is M. avium subsp.
hominissuis. In one embodiment, the nontuberculous mycobacterial
lung infection is a recalcitrant nontuberculous mycobacterial lung
infection.
[0043] In another embodiment, a cystic fibrosis patient is treated
for a bacterial infection with one of the systems provided herein.
In a further embodiment, the bacterial infection is a lung
infection due to Pseudomonas aeruginosa. In yet another embodiment,
a patient is treated for a pulmonary infection associated with
bronchiectasis with one of the systems provided herein.
[0044] "Prophylaxis," as used herein, can mean complete prevention
of an infection or disease, or prevention of the development of
symptoms of that infection or disease; a delay in the onset of an
infection or disease or its symptoms; or a decrease in the severity
of a subsequently developed infection or disease or its
symptoms.
[0045] The term "antibacterial" is art-recognized and refers to the
ability of the compounds of the present invention to prevent,
inhibit or destroy the growth of microbes of bacteria. Examples of
bacteria are provided above.
[0046] The term "antimicrobial" is art-recognized and refers to the
ability of the aminoglycoside compounds of the present invention to
prevent, inhibit, delay or destroy the growth of microbes such as
bacteria, fungi, protozoa and viruses.
[0047] "Effective amount" means an amount of an aminoglycoside
(e.g., amikacin) used in the present invention sufficient to result
in the desired therapeutic response. The effective amount of the
formulation provided herein comprises both free and liposomal
complexed aminoglycoside. For example, the liposomal complexed
aminoglycoside, in one embodiment, comprises aminoglycoside
encapsulated in a liposome, or complexed with a liposome, or a
combination thereof.
[0048] In one embodiment, the aminoglycoside is selected from
amikacin, apramycin, arbekacin, astromicin, capreomycin, dibekacin,
framycetin, gentamicin, hygromycin B, isepamicin, kanamycin,
neomycin, netilmicin, paromomycin, rhodestreptomycin, ribostamycin,
sisomicin, spectinomycin, streptomycin, tobramycin or verdamicin.
In another embodiment, the aminoglycoside is selected from an
aminoglycoside set forth in Table C, below.
TABLE-US-00004 TABLE C AC4437 dibekacin K-4619 sisomicin amikacin
dactimicin isepamicin rhodestreptomycin arbekacin etimicin KA-5685
sorbistin apramycin framycetin kanamycin spectinomycin astromicin
gentamicin neomycin sporaricin bekanamycin H107 netilmicin
streptomycin boholmycin hygromycin paromomycin tobramycin
brulamycin hygromycin B plazomicin verdamicin capreomycin
inosamycin ribostamycin vertilmicin
[0049] In one embodiment, the aminoglycoside is an aminoglycoside
free base, or its salt, solvate, or other non-covalent derivative.
In a further embodiment, the aminoglycoside is amikacin. Included
as suitable aminoglycosides used in the drug formulations of the
present invention are pharmaceutically acceptable addition salts
and complexes of drugs. In cases where the compounds may have one
or more chiral centers, unless specified, the present invention
comprises each unique racemic compound, as well as each unique
nonracemic compound. In cases in which the active agents have
unsaturated carbon-carbon double bonds, both the cis (Z) and trans
(E) isomers are within the scope of this invention. In cases where
the active agents exist in tautomeric forms, such as keto-enol
tautomers, each tautomeric form is contemplated as being included
within the invention. Amikacin, in one embodiment, is present in
the pharmaceutical formulation as amikacin base, or amikacin salt,
for example, amikacin sulfate or amikacin disulfate. In one
embodiment, a combination of one or more of the above
aminoglycosides is used in the formulations, systems and methods
described herein. In a further embodiment, the combination
comprises amikacin.
[0050] The therapeutic response can be any response that a user
(e.g., a clinician) will recognize as an effective response to the
therapy. The therapeutic response will generally be a reduction,
inhibition, delay or prevention in growth of or reproduction of one
or more bacterium, or the killing of one or more bacterium, as
described above. A therapeutic response may also be reflected in an
improvement in pulmonary function, for example forced expiratory
volume in one second (FEV.sub.1). It is further within the skill of
one of ordinary skill in the art to determine appropriate treatment
duration, appropriate doses, and any potential combination
treatments, based upon an evaluation of therapeutic response.
[0051] "Liposomal dispersion" refers to a solution or suspension
comprising a plurality of liposomes.
[0052] An "aerosol", as used herein, is a gaseous suspension of
liquid particles. The aerosol provided herein comprises particles
of the liposomal dispersion.
[0053] A "nebulizer" or an "aerosol generator" is a device that
converts a liquid into an aerosol of a size that can be inhaled
into the respiratory tract. Pneumonic, ultrasonic, electronic
nebulizers, e.g., passive electronic mesh nebulizers, active
electronic mesh nebulizers and vibrating mesh nebulizers are
amenable for use with the invention if the particular nebulizer
emits an aerosol with the required properties, and at the required
output rate.
[0054] The process of pneumatically converting a bulk liquid into
small droplets is called atomization. The operation of a pneumatic
nebulizer requires a pressurized gas supply as the driving force
for liquid atomization. Ultrasonic nebulizers use electricity
introduced by a piezoelectric element in the liquid reservoir to
convert a liquid into respirable droplets. Various types of
nebulizers are described in Respiratory Care, Vol. 45, No. 6, pp.
609-622 (2000), the disclosure of which is incorporated herein by
reference in its entirety. The terms "nebulizer" and "aerosol
generator" are used interchangeably throughout the specification.
"Inhalation device", "inhalation system" and "atomizer" are also
used in the literature interchangeably with the terms "nebulizer"
and "aerosol generator".
[0055] "Fine particle fraction" or "FPF", as used herein, refers to
the fraction of the aerosol having a particle size less than 5
.mu.m in diameter, as measured by cascade impaction. FPF is usually
expressed as a percentage.
[0056] "Mass median diameter" or "MMD" is determined by laser
diffraction or impactor measurements, and is the average particle
diameter by mass.
[0057] "Mass median aerodynamic diameter" or "MMAD" is normalized
regarding the aerodynamic separation of aqua aerosol droplets and
is determined impactor measurements, e.g., the Anderson Cascade
Impactor (ACI) or the Next Generation Impactor (NGI). The gas flow
rate, in one embodiment, is 28 Liter per minute by the Anderson
Cascade Impactor (ACI) and 15 Liter per minute by the Next
Generation Impactor (NGI). "Geometric standard deviation" or "GSD"
is a measure of the spread of an aerodynamic particle size
distribution.
[0058] In one embodiment, the present invention provides a system
for treating a pulmonary infection or providing prophylaxis against
a pulmonary infection. Treatment is achieved via delivery of the
aminoglycoside formulation by inhalation via nebulization. In one
embodiment, the pharmaceutical formulation comprises an
aminoglycoside agent, e.g., an aminoglycoside.
[0059] The pharmaceutical formulation, as provided herein, is a
liposomal dispersion. Specifically, the pharmaceutical formulation
is a dispersion comprising a "liposomal complexed aminoglycoside"
or an "aminoglycoside encapsulated in a liposome". A "liposomal
complexed aminoglycoside" includes embodiments where the
aminoglycoside (or combination of aminoglycosides) is encapsulated
in a liposome, and includes any form of aminoglycoside composition
where at least about 1% by weight of the aminoglycoside is
associated with the liposome either as part of a complex with a
liposome, or as a liposome where the aminoglycoside may be in the
aqueous phase or the hydrophobic bilayer phase or at the
interfacial headgroup region of the liposomal bilayer.
[0060] In one embodiment, the lipid component of the liposome
comprises electrically neutral lipids, positively charged lipids,
negatively charged lipids, or a combination thereof. In another
embodiment, the lipid component comprises electrically neutral
lipids. In a further embodiment, the lipid component consists
essentially of electrically neutral lipids. In even a further
embodiment, the lipid component consists of electrically neutral
lipids, e.g., a sterol and a phospholipid.
[0061] As provided above, liposomal complexed aminoglycoside
embodiments include embodiments where the aminoglycoside is
encapsulated in a liposome. In addition, the liposomal complexed
aminoglycoside describes any composition, solution or suspension
where at least about 1% by weight of the aminoglycoside is
associated with the lipid either as part of a complex with the
liposome, or as a liposome where the aminoglycoside may be in the
aqueous phase or the hydrophobic bilayer phase or at the
interfacial headgroup region of the liposomal bilayer. In one
embodiment, prior to nebulization, at least about 5%, at least
about 10%, at least about 20%, at least about 25%, at least about
50%, at least about 75%, at least about 80%, at least about 85%, at
least about 90% or at least about 95% of the aminoglycoside in the
formulation is so associated. Association, in one embodiment, is
measured by separation through a filter where lipid and
lipid-associated drug is retained (i.e., in the retentate) and free
drug is in the filtrate.
[0062] The formulations, systems and methods provided herein
comprise a lipid-encapsulated or lipid-associated aminoglycoside
agent. The lipids used in the pharmaceutical formulations of the
present invention can be synthetic, semi-synthetic or
naturally-occurring lipids, including phospholipids, tocopherols,
sterols, fatty acids, negatively-charged lipids and cationic
lipids.
[0063] In one embodiment, at least one phospholipid is present in
the pharmaceutical formulation. In one embodiment, the phospholipid
is selected from: phosphatidylcholine (EPC), phosphatidylglycerol
(PG), phosphatidylinositol (PI), phosphatidylserine (PS),
phosphatidylethanolamine (PE), and phosphatidic acid (PA); the soya
counterparts, soy phosphatidylcholine (SPC); SPG, SPS, SPI, SPE,
and SPA; the hydrogenated egg and soya counterparts (e.g., HEPC,
HSPC), phospholipids made up of ester linkages of fatty acids in
the 2 and 3 of glycerol positions containing chains of 12 to 26
carbon atoms and different head groups in the 1 position of
glycerol that include choline, glycerol, inositol, serine,
ethanolamine, as well as the corresponding phosphatidic acids. The
carbon chains on these fatty acids can be saturated or unsaturated,
and the phospholipid may be made up of fatty acids of different
chain lengths and different degrees of unsaturation.
[0064] In one embodiment, the pharmaceutical formulation includes
dipalmitoylphosphatidylcholine (DPPC), a major constituent of
naturally-occurring lung surfactant. In one embodiment, the lipid
component of the pharmaceutical formulation comprises DPPC and
cholesterol, or consists essentially of DPPC and cholesterol, or
consists of DPPC and cholesterol. In a further embodiment, the DPPC
and cholesterol have a mole ratio in the range of from about 19:1
to about 1:1, or about 9:1 to about 1:1, or about 4:1 to about 1:1,
or about 2:1 to about 1:1, or about 1.86:1 to about 1:1. In even a
further embodiment, the DPPC and cholesterol have a mole ratio of
about 2:1 or about 1:1. In one embodiment, DPPC and cholesterol are
provided in an aminoglycoside formulation, e.g., an aminoglycoside
formulation.
[0065] Other examples of lipids for use with the invention include,
but are not limited to, dimyristoylphosphatidycholine (DMPC),
dimyristoylphosphatidylglycerol (DMPG),
dipalmitoylphosphatidcholine (DPPC),
dipalmitoylphosphatidylglycerol (DPPG),
distearoylphosphatidylcholine (DSPC),
distearoylphosphatidylglycerol (DSPG),
dioleylphosphatidyl-ethanolamine (DOPE), mixed phospholipids such
as palmitoylstearoylphosphatidyl-choline (PSPC), and single
acylated phospholipids, for example,
mono-oleoyl-phosphatidylethanolamine (MOPE).
[0066] In one embodiment, the at least one lipid component
comprises a sterol. In a further embodiment, the at least one lipid
component comprises a sterol and a phospholipid, or consists
essentially of a sterol and a phospholipid, or consists of a sterol
and a phospholipid. Sterols for use with the invention include, but
are not limited to, cholesterol, esters of cholesterol including
cholesterol hemi-succinate, salts of cholesterol including
cholesterol hydrogen sulfate and cholesterol sulfate, ergosterol,
esters of ergosterol including ergosterol hemi-succinate, salts of
ergosterol including ergosterol hydrogen sulfate and ergosterol
sulfate, lanosterol, esters of lanosterol including lanosterol
hemi-succinate, salts of lanosterol including lanosterol hydrogen
sulfate, lanosterol sulfate and tocopherols. The tocopherols can
include tocopherols, esters of tocopherols including tocopherol
hemi-succinates, salts of tocopherols including tocopherol hydrogen
sulfates and tocopherol sulfates. The term "sterol compound"
includes sterols, tocopherols and the like.
[0067] In one embodiment, at least one cationic lipid (positively
charged lipid) is provided in the systems described herein. The
cationic lipids used can include ammonium salts of fatty acids,
phospholids and glycerides. The fatty acids include fatty acids of
carbon chain lengths of 12 to 26 carbon atoms that are either
saturated or unsaturated. Some specific examples include:
myristylamine, palmitylamine, laurylamine and stearylamine,
dilauroyl ethylphosphocholine (DLEP), dimyristoyl
ethylphosphocholine (DMEP), dipalmitoyl ethylphosphocholine (DPEP)
and distearoyl ethylphosphocholine (DSEP),
N-(2,3-di-(9-(Z)-octadecenyloxy)-prop-1-yl-N,N,N-trimethylammoniu-m
chloride (DOTMA) and 1,2-bis(oleoyloxy)-3-(trimethylammonio)
propane (DOTAP).
[0068] In one embodiment, at least one anionic lipid (negatively
charged lipid) is provided in the systems described herein. The
negatively-charged lipids which can be used include
phosphatidyl-glycerols (PGs), phosphatidic acids (PAs),
phosphatidylinositols (PIs) and the phosphatidyl serines (PSs).
Examples include DMPG, DPPG, DSPG, DMPA, DPPA, DSPA, DMPI, DPPI,
DSPI, DMPS, DPPS and DSPS.
[0069] Without wishing to be bound by theory, phosphatidylcholines,
such as DPPC, aid in the uptake of the aminoglycoside agent by the
cells in the lung (e.g., the alveolar macrophages) and helps to
maintain the aminoglycoside agent in the lung. The negatively
charged lipids such as the PGs, PAs, PSs and PIs, in addition to
reducing particle aggregation, are thought to play a role in the
sustained activity characteristics of the inhalation formulation as
well as in the transport of the formulation across the lung
(transcytosis) for systemic uptake. The sterol compounds, without
wishing to be bound by theory, are thought to affect the release
characteristics of the formulation.
[0070] Liposomes are completely closed lipid bilayer membranes
containing an entrapped aqueous volume. Liposomes may be
unilamellar vesicles (possessing a single membrane bilayer) or
multilamellar vesicles (onion-like structures characterized by
multiple membrane bilayers, each separated from the next by an
aqueous layer) or a combination thereof. The bilayer is composed of
two lipid monolayers having a hydrophobic "tail" region and a
hydrophilic "head" region. The structure of the membrane bilayer is
such that the hydrophobic (nonpolar) "tails" of the lipid
monolayers orient toward the center of the bilayer while the
hydrophilic "heads" orient towards the aqueous phase.
[0071] Liposomes can be produced by a variety of methods (see,
e.g., Cullis et al. (1987)). In one embodiment, one or more of the
methods described in U.S. Patent Application Publication No.
2008/0089927 are used herein to produce the aminoglycoside
encapsulated lipid formulations (liposomal dispersion). The
disclosure of U.S. Patent Application Publication No. 2008/0089927
is incorporated by reference in its entirety for all purposes. For
example, in one embodiment, at least one lipid and an
aminoglycoside are mixed with a coacervate (i.e., a separate liquid
phase) to form the liposome formulation. The coacervate can be
formed to prior to mixing with the lipid, during mixing with the
lipid or after mixing with the lipid. Additionally, the coacervate
can be a coacervate of the active agent.
[0072] In one embodiment, the liposomal dispersion is formed by
dissolving one or more lipids in an organic solvent forming a lipid
solution, and the aminoglycoside coacervate forms from mixing an
aqueous solution of the aminoglycoside with the lipid solution. In
a further embodiment, the organic solvent is ethanol. In even a
further embodiment, the one or more lipids comprise a phospholipid
and a sterol.
[0073] In one embodiment, liposomes are produces by sonication,
extrusion, homogenization, swelling, electroformation, inverted
emulsion or a reverse evaporation method. Bangham's procedure (J.
Mol. Biol. (1965)) produces ordinary multilamellar vesicles (MLVs).
Lenk et al. (U.S. Pat. Nos. 4,522,803, 5,030,453 and 5,169,637),
Fountain et al. (U.S. Pat. No. 4,588,578) and Cullis et al. (U.S.
Pat. No. 4,975,282) disclose methods for producing multilamellar
liposomes having substantially equal interlamellar solute
distribution in each of their aqueous compartments. Paphadjopoulos
et al., U.S. Pat. No. 4,235,871, discloses preparation of
oligolamellar liposomes by reverse phase evaporation. Each of the
methods is amenable for use with the present invention.
[0074] Unilamellar vesicles can be produced from MLVs by a number
of techniques, for example, the extrusion techniques of U.S. Pat.
No. 5,008,050 and U.S. Pat. No. 5,059,421. Sonication and
homogenization cab be so used to produce smaller unilamellar
liposomes from larger liposomes (see, for example, Paphadjopoulos
et al. (1968); Deamer and Uster (1983); and Chapman et al.
(1968)).
[0075] The liposome preparation of Bangham et al. (J. Mol. Biol.
13, 1965, pp. 238-252) involves suspending phospholipids in an
organic solvent which is then evaporated to dryness leaving a
phospholipid film on the reaction vessel. Next, an appropriate
amount of aqueous phase is added, the 60 mixture is allowed to
"swell", and the resulting liposomes which consist of multilamellar
vesicles (MLVs) are dispersed by mechanical means. This preparation
provides the basis for the development of the small sonicated
unilamellar vesicles described by Papahadjopoulos et al. (Biochim.
Biophys. Acta. 135, 1967, pp. 624-638), and large unilamellar
vesicles.
[0076] Techniques for producing large unilamellar vesicles (LUVs),
such as, reverse phase evaporation, infusion procedures, and
detergent dilution, can be used to produce liposomes for use in the
pharmaceutical formulations provided herein. A review of these and
other methods for producing liposomes may be found in the text
Liposomes, Marc Ostro, ed., Marcel Dekker, Inc., New York, 1983,
Chapter 1, which is incorporated herein by reference. See also
Szoka, Jr. et al., (Ann. Rev. Biophys. Bioeng. 9, 1980, p. 467),
which is also incorporated herein by reference in its entirety for
all purposes.
[0077] Other techniques for making liposomes include those that
form reverse-phase evaporation vesicles (REV), U.S. Pat. No.
4,235,871. Another class of liposomes that may be used is
characterized as having substantially equal lamellar solute
distribution. This class of liposomes is denominated as stable
plurilamellar vesicles (SPLV) as defined in U.S. Pat. No.
4,522,803, and includes monophasic vesicles as described in U.S.
Pat. No. 4,588,578, and frozen and thawed multilamellar vesicles
(FATMLV) as described above.
[0078] A variety of sterols and their water soluble derivatives
such as cholesterol hemisuccinate have been used to form liposomes;
see, e.g., U.S. Pat. No. 4,721,612. Mayhew et al., PCT Publication
No. WO 85/00968, described a method for reducing the toxicity of
drugs by encapsulating them in liposomes comprising
alpha-tocopherol and certain derivatives thereof. Also, a variety
of tocopherols and their water soluble derivatives have been used
to form liposomes, see PCT Publication No. 87/02219.
[0079] The pharmaceutical formulation, in one embodiment,
pre-nebulization, comprises liposomes with a mean diameter, that is
measured by a light scattering method, of approximately 0.01
microns to approximately 3.0 microns, for example, in the range
about 0.2 to about 1.0 microns. In one embodiment, the mean
diameter of the liposomes in the formulation is about 200 nm to
about 300 nm, about 210 nm to about 290 nm, about 220 nm to about
280 nm, about 230 nm to about 280 nm, about 240 nm to about 280 nm,
about 250 nm to about 280 nm or about 260 nm to about 280 nm. The
sustained activity profile of the liposomal product can be
regulated by the nature of the lipid membrane and by inclusion of
other excipients in the composition.
[0080] In order to minimize dose volume and reduce patient dosing
time, in one embodiment, it is important that liposomal entrapment
of the aminoglycoside (e.g., the aminoglycoside amikacin) be highly
efficient and that the L/D ratio be at as low a value as possible
and/or practical while keeping the liposomes small enough to
penetrate patient mucus and biofilms, e.g., Pseudomonas biofilms.
In one embodiment, the L/D ratio in liposomes provided herein is
0.7 or about 0.7 (w/w). In a further embodiment, the liposomes
provided herein are small enough to effectively penetrate a
bacterial biofilm (e.g., Pseudomonas biofilm). In even a further
embodiment, the mean diameter of the liposomes, as measured by
light scattering is about 260 to about 280 nm.
[0081] The lipid to drug ratio in the pharmaceutical formulations
provided herein, in one embodiment, is 3 to 1 or less, 2.5 to 1 or
less, 2 to 1 or less, 1.5 to 1 or less, or 1 to 1 or less. The
lipid to drug ratio in the pharmaceutical formulations provided
herein, in another embodiment, is less than 3 to 1, less than 2.5
to 1, less than 2 to 1, less than 1.5 to 1, or less than 1 to 1. In
a further embodiment, the lipid to drug ratio is about 0.7 to or
less or about 0.7 to 1. In one embodiment, one of the lipids or
lipid combinations in Table 1, below, is used in the pharmaceutical
formulation of the invention.
TABLE-US-00005 TABLE 1 Lipids amenable for use with the invention
Lipid/aminoglycoside Lipid(s) Mole ratio (w/w) DPPC -- 1.1
DPPC/DOPG 9:1 1.0 DPPC/DOPG 7:1 3.9 DPPC/DOPG 1:1 2.8 DPPC/DOPG
0.5:1 2.7 DOPG -- 2.6 DPPC/Cholesterol about 1:1 about 0.7
DPPC/Cholesterol 1:1 0.7 DPPC/Cholesterol 19:1 1.0 DPPC/Cholesterol
9:1 1.2 DPPC/Cholesterol 4:1 1.7 DPPC/Cholesterol 1.86:1 2.1
DPPC/Cholesterol 1:1 2.7 DPPC/DOPC/Cholesterol 8.55:1:0.45 2.0
DPPC/DOPC/Cholesterol 6.65:1:0.35 3.0 DPPC/DOPC/Cholesterol 19:20:1
2.5 DPPC/DOPC/Cholesterol 8.55:1:0.45 3.8 DPPC/DOPC/Cholesterol
6.65:1:0.35 4.1 DPPC/DOPC/Cholesterol 19:20:1 4.2
DPPC/DOPC/DOPG/Cholesterol 42:4:9:45 3.7 DPPC/DOPC/DOPG/Cholesterol
59:5:6:30 3.7
[0082] In one embodiment, the system provided herein comprises an
aminoglycoside formulation, for example, an amikacin formulation,
e.g., amikacin base formulation. In one embodiment, the amount of
aminoglycoside provided in the system is about 450 mg, about 500
mg, about 550 mg, about 560 mg, about 570 mg, about 580 mg, about
590 mg, about 600 mg or about 610 mg. In another embodiment, the
amount of aminoglycoside provided in the system is from about 500
mg to about 600 mg, or from about 500 mg to about 650 mg, or from
about 525 mg to about 625 mg, or from about 550 mg to about 600 mg.
In one embodiment, the amount of aminoglycoside administered to the
subject is about 560 mg and is provided in an 8 mL formulation. In
one embodiment, the amount of aminoglycoside administered to the
subject is about 590 mg and is provided in an 8 mL formulation. In
one embodiment, the amount of aminoglycoside administered to the
subject is about 600 mg and is provided in an 8 mL formulation. In
one embodiment, the aminoglycoside is amikacin and the amount of
amikacin provided in the system is about 450 mg, about 500 mg,
about 550 mg, about 560 mg, about 570 mg, about 580 mg, about 590
mg, about 600 mg or about 610 mg. In another embodiment, the
aminoglycoside is amikacin and the amount of amikacin provided in
the system is from about 500 mg to about 650 mg, or from about 525
mg to about 625 mg, or from about 550 mg to about 600 mg. In one
embodiment, the aminoglycoside is amikacin and the amount of
amikacin administered to the subject is about 560 mg, and is
provided in an 8 mL formulation. In one embodiment, the
aminoglycoside is amikacin and the amount of amikacin administered
to the subject is about 590 mg, and is provided in an 8 mL
formulation. In one embodiment, the aminoglycoside is amikacin and
the amount of aminoglycoside administered to the subject is about
600 mg and is provided in an 8 mL formulation.
[0083] In one embodiment, the system provided herein comprises an
aminoglycoside formulation, for example, an amikacin (base
formulation). In one embodiment, the aminoglycoside formulation
provided herein comprises about 60 mg/mL aminoglycoside, about 65
mg/mL aminoglycoside, about 70 mg/mL aminoglycoside, about 75 mg/mL
aminoglycoside, about 80 mg/mL aminoglycoside, about 85 mg/mL
aminoglycoside, or about 90 mg/mL aminoglycoside. In a further
embodiment, the aminoglycoside is amikacin.
[0084] In one embodiment, the system provided herein comprises an
about 8 mL liposomal amikacin formulation. In one embodiment, the
density of the liposomal amikacin formulation is about 1.05
gram/mL; and in one embodiment, approximately 8.4 grams of the
liposomal amikacin formulation per dose is present in the system of
the invention. In a further embodiment, the entire volume of the
formulation is administered to a subject in need thereof.
[0085] In one embodiment, the pharmaceutical formulation provided
herein comprises at least one aminoglycoside, at least one
phospholipid and a sterol. In a further embodiment, the
pharmaceutical formulation comprises an aminoglycoside, DPPC and
cholesterol. In one embodiment, the pharmaceutical formulation is
the formulation provided in Table 2, below.
TABLE-US-00006 TABLE 2 Pharmaceutical Formulations Component
Concentration Formulation A (pH 6.0-7.0) Aminoglycoside 60-80 mg/mL
Phospholipid 30-40 mg/mL Sterol 10-20 mg/mL Salt 0.5%-5.0%
Formulation B (pH 6.0-7.0) Amikacin 60-80 mg/mL DPPC 30-40 mg/mL
Cholesterol 10-20 mg/mL NaCl 0.5%-5.0% Formulation C (pH 6.0-7.0)
Amikacin 70-80 mg/mL DPPC 35-40 mg/mL Cholesterol 15-20 mg/mL NaCl
0.5%-5.0% Formulation D (pH ~6.5) Aminoglycoside ~70 mg/mL
Phospholipid ~32-35 mg/mL Sterol ~16-17 mg/mL Salt ~1.5%
Formulation E (pH ~6.5) Amikacin ~70 mg/mL DPPC ~32-35 mg/mL
Cholesterol ~16-17 mg/mL NaCl ~1.5% Formulation F (pH ~6.5)
Amikacin ~70 mg/mL DPPC ~30-35 mg/mL Cholesterol ~15-17 mg/mL NaCl
~1.5%
[0086] It should be noted that increasing aminoglycoside
concentration alone may not result in a reduced dosing time. For
example, in one embodiment, the lipid to drug ratio is fixed, and
as amikacin concentration is increased (and therefore lipid
concentration is increased, since the ratio of the two is fixed,
for example at .about.0.7:1), the viscosity of the solution also
increases, which slows nebulization time.
[0087] In one embodiment, prior to nebulization of the
aminoglycoside formulation, about 70% to about 100% of the
aminoglycoside present in the formulation is liposomal complexed.
In a further embodiment, the aminoglycoside is an aminoglycoside.
In even a further embodiment, the aminoglycoside is amikacin. In
another embodiment, prior to nebulization, about 80% to about 99%,
or about 85% to about 99%, or about 90% to about 99% or about 95%
to about 99% or about 96% to about 99% of the aminoglycoside
present in the formulation is liposomal complexed. In a further
embodiment, the aminoglycoside is amikacin or tobramycin. In even a
further embodiment, the aminoglycoside is amikacin. In another
embodiment, prior to nebulization, about 98% of the aminoglycoside
present in the formulation is liposomal complexed. In a further
embodiment, the aminoglycoside is amikacin or tobramycin. In even a
further embodiment, the aminoglycoside is amikacin.
[0088] In one embodiment, upon nebulization, about 20% to about 50%
of the liposomal complexed aminoglycoside agent is released, due to
shear stress on the liposomes. In a further embodiment, the
aminoglycoside agent is an amikacin. In another embodiment, upon
nebulization, about 25% to about 45%, or about 30% to about 40% of
the liposomal complexed aminoglycoside agent is released, due to
shear stress on the liposomes. In a further embodiment, the
aminoglycoside agent is amikacin.
[0089] As provided herein, the present invention provides methods
and systems for treatment of lung infections by inhalation of a
liposomal aminoglycoside formulation via nebulization. The
formulation, in one embodiment, is administered via a nebulizer,
which provides an aerosol mist of the formulation for delivery to
the lungs of a subject.
[0090] In one embodiment, the nebulizer described herein generates
an aerosol (i.e., achieves a total output rate) of the
aminoglycoside pharmaceutical formulation at a rate greater than
about 0.53 g per minute, greater than about 0.54 g per minute,
greater than about 0.55 g per minute, greater than about 0.58 g per
minute, greater than about 0.60 g per minute, greater than about
0.65 g per minute or greater than about 0.70 g per minute. In
another embodiment, the nebulizer described herein generates an
aerosol (i.e., achieves a total output rate) of the aminoglycoside
pharmaceutical formulation at about 0.53 g per minute to about 0.80
g per minute, at about 0.53 g per minute to about 0.70 g per
minute, about 0.55 g per min to about 0.70 g per minute, about 0.53
g per minute to about 0.65 g per minute, or about 0.60 g per minute
to about 0.70 g per minute. In yet another embodiment, the
nebulizer described herein generates an aerosol (i.e., achieves a
total output rate) of the aminoglycoside pharmaceutical formulation
at about 0.53 g per minute to about 0.75 g per minute, about 0.55 g
per min to about 0.75 g per minute, about 0.53 g per minute to
about 0.65 g per minute, or about 0.60 g per minute to about 0.75 g
per minute.
[0091] Upon nebulization, the liposomes in the pharmaceutical
formulation leak drug. In one embodiment, the amount of liposomal
complexed aminoglycoside post-nebulization is about 45% to about
85%, or about 50% to about 80% or about 51% to about 77%. These
percentages are also referred to herein as "percent associated
aminoglycoside post-nebulization". As provided herein, in one
embodiment, the liposomes comprise an aminoglycoside, e.g.,
amikacin. In one embodiment, the percent associated aminoglycoside
post-nebulization is from about 60% to about 70%. In a further
embodiment, the aminoglycoside is amikacin. In another embodiment,
the percent associated aminoglycoside post-nebulization is about
67%, or about 65% to about 70%. In a further embodiment, the
aminoglycoside is amikacin.
[0092] In one embodiment, the percent associated aminoglycoside
post-nebulization is measured by reclaiming the aerosol from the
air by condensation in a cold-trap, and the liquid is subsequently
assayed for free and encapsulated aminoglycoside (associated
aminoglycoside).
[0093] In one embodiment, the MMAD of the aerosol of the
pharmaceutical formulation is less than 4.9 .mu.m, less than 4.5
.mu.m, less than 4.3 .mu.m, less than 4.2 .mu.m, less than 4.1
.mu.m, less than 4.0 .mu.m or less than 3.5 .mu.m, as measured by
the ACI at a gas flow rate of about 28 L/minute, or by the Next
Generation Impactor NGI at a gas flow rate of about 15
L/minute.
[0094] In one embodiment, the MMAD of the aerosol of the
pharmaceutical formulation is about 1.0 .mu.m to about 4.2 .mu.m,
about 3.2 .mu.m to about 4.2 .mu.m, about 3.4 .mu.m to about 4.0
.mu.m, about 3.5 jam to about 4.0 .mu.m or about 3.5 .mu.m to about
4.2 .mu.m, as measured by the ACI. In one embodiment, the MMAD of
the aerosol of the pharmaceutical formulation is about 2.0 .mu.m to
about 4.9 .mu.m, about 4.4 .mu.m to about 4.9 .mu.m, about 4.5
.mu.m to about 4.9 .mu.m, or about 4.6 .mu.m to about 4.9 .mu.m, as
measured by the NGI.
[0095] In another embodiment, the nebulizer described herein
generates an aerosol of the aminoglycoside pharmaceutical
formulation at a rate greater than about 0.53 g per minute, greater
than about 0.55 g per minute, or greater than about 0.60 g per
minute or about 0.60 g per minute to about 0.70 g per minute. In a
further embodiment, the FPF of the aerosol is greater than or equal
to about 64%, as measured by the ACI, greater than or equal to
about 70%, as measured by the ACI, greater than or equal to about
51%, as measured by the NGI, or greater than or equal to about 60%,
as measured by the NGI.
[0096] In one embodiment, the system provided herein comprises a
nebulizer selected from an electronic mesh nebulizer, pneumonic
(jet) nebulizer, ultrasonic nebulizer, breath-enhanced nebulizer
and breath-actuated nebulizer. In one embodiment, the nebulizer is
portable.
[0097] The principle of operation of a pneumonic nebulizer is
generally known to those of ordinary skill in the art and is
described, e.g., in Respiratory Care, Vol. 45, No. 6, pp. 609-622
(2000). Briefly, a pressurized gas supply is used as the driving
force for liquid atomization in a pneumatic nebulizer. Compressed
gas is delivered, which causes a region of negative pressure. The
solution to be aerosolized is then delivered into the gas stream
and is sheared into a liquid film. This film is unstable and breaks
into droplets because of surface tension forces. Smaller particles,
i.e., particles with the MMAD and FPF properties described above,
can then be formed by placing a baffle in the aerosol stream. In
one pneumonic nebulizer embodiment, gas and solution is mixed prior
to leaving the exit port (nozzle) and interacting with the baffle.
In another embodiment, mixing does not take place until the liquid
and gas leave the exit port (nozzle). In one embodiment, the gas is
air, O.sub.2 and/or CO.sub.2.
[0098] In one embodiment, droplet size and output rate can be
tailored in a pneumonic nebulizer. However, consideration should be
paid to the formulation being nebulized, and whether the properties
of the formulation (e.g., % associated aminoglycoside) are altered
due to the modification of the nebulizer. For example, in one
embodiment, the gas velocity and/or pharmaceutical formulation
velocity is modified to achieve the output rate and droplet sizes
of the present invention. Additionally or alternatively, the flow
rate of the gas and/or solution can be tailored to achieve the
droplet size and output rate of the invention. For example, an
increase in gas velocity, in one embodiment, decreased droplet
size. In one embodiment, the ratio of pharmaceutical formulation
flow to gas flow is tailored to achieve the droplet size and output
rate of the invention. In one embodiment, an increase in the ratio
of liquid to gas flow increases particle size.
[0099] In one embodiment, a pneumonic nebulizer output rate is
increased by increasing the fill volume in the liquid reservoir.
Without wishing to be bound by theory, the increase in output rate
may be due to a reduction of dead volume in the nebulizer.
Nebulization time, in one embodiment, is reduced by increasing the
flow to power the nebulizer. See, e.g., Clay et al. (1983). Lancet
2, pp. 592-594 and Hess et al. (1996). Chest 110, pp. 498-505.
[0100] In one embodiment, a reservoir bag is used to capture
aerosol during the nebulization process, and the aerosol is
subsequently provided to the subject via inhalation. In another
embodiment, the nebulizer provided herein includes a valved
open-vent design. In this embodiment, when the patient inhales
through the nebulizer, nebulizer output is increased. During the
expiratory phase, a one-way valve diverts patient flow away from
the nebulizer chamber.
[0101] In one embodiment, the nebulizer provided herein is a
continuous nebulizer. In other words, refilling the nebulizer with
the pharmaceutical formulation while administering a dose is not
needed. Rather, the nebulizer has at least an 8 mL capacity or at
least a 10 mL capacity.
[0102] In one embodiment, a vibrating mesh nebulizer is used to
deliver the aminoglycoside formulation of the invention to a
patient in need thereof. In one embodiment, the nebulizer membrane
vibrates at an ultrasonic frequency of about 100 kHz to about 250
kHz, about 110 kHz to about 200 kHz, about 110 kHz to about 200
kHz, about 110 kHz to about 150 kHz. In one embodiment, the
nebulizer membrane vibrates at a frequency of about 117 kHz upon
the application of an electric current.
[0103] In one embodiment, the nebulizer provided herein does not
use an air compressor and therefore does not generate an air flow.
In one embodiment, aerosol is produced by the aerosol head which
enters the mixing chamber of the device. When the patient inhales,
air enters the mixing chamber via one-way inhalation valves in the
back of the mixing chamber and carries the aerosol through the
mouthpiece to the patient. On exhalation, the patient's breath
flows through the one-way exhalation valve on the mouthpiece of the
device. In one embodiment, the nebulizer continues to generate
aerosol into the mixing chamber which is then drawn in by the
subject on the next breath--and this cycle continues until the
nebulizer medication reservoir is empty.
[0104] Although not limited thereto, the present invention, in one
embodiment, is carried out with one of the aerosol generators
(nebulizers) depicted in FIGS. 1, 2, 3 and 4. Additionally, the
systems of the invention, in one embodiment, include a nebulizer
described in European Patent Applications 11169080.6 and/or
10192385.2. These applications are incorporated by reference in
their entireties.
[0105] FIG. 1 shows a therapeutic aerosol device 1 with a
nebulizing chamber 2, a mouthpiece 3 and a membrane aerosol
generator 4 with an oscillating membrane 5. The oscillating
membrane may, for example, be brought to oscillation by annular
piezo elements (not shown), examples of which are described in WO
1997/29851.
[0106] When in use, the pharmaceutical formulation is located on
one side of the oscillating membrane 5, see FIGS. 1, 2 and 4, and
this liquid is then transported through openings in the oscillating
membrane 5 and emitted on the other side of the oscillating
membrane 5, see bottom of FIG. 1, FIG. 2, as an aerosol into the
nebulizing chamber 2. The patient is able to breathe in the aerosol
present in the nebulizing chamber 2 at the mouthpiece 3.
[0107] The oscillating membrane 5 comprises a plurality of through
holes. Droplets of the aminoglycoside formulation are generated
when the aminoglycoside pharmaceutical formulation passes through
the membrane. In one embodiment, the membrane is vibratable, a so
called active electronic mesh nebulizer, for example the eFlow.RTM.
nebulizer from PARI Pharma, HL100 nebulizer from Health and Life,
or the Aeroneb Got from Aerogen (Novartis). In a further
embodiment, the membrane vibrates at an ultrasonic frequency of
about 100 kHz to about 150 kHz, about 110 kHz to about 140 kHz, or
about 110 kHz to about 120 kHz. In a further embodiment, the
membrane vibrates at a frequency of about 117 kHz upon the
application of an electric current. In a further embodiment, the
membrane is fixed and the a further part of the fluid reservoir or
fluid supply is vibratable, a so called passive electronic mesh
nebulizer, for example the MicroAir Electronic Nebulizer Model U22
from Omron or the I-Neb I-neb AAD Inhalation System from Philips
Respironics.
[0108] In one embodiment, the length of the nozzle portion of the
through holes formed in the membrane (e.g., vibratable membrane)
influences the total output rate (TOR) of the aerosol generator. In
particular, it has been found that the length of the nozzle portion
is directly proportional to the total output rate, wherein the
shorter the nozzle portion, the higher the TOR and vice versa.
[0109] In one embodiment, the nozzle portion is sufficiently short
and small in diameter as compared to the upstream portion of the
through hole. In a further embodiment, the length of the portions
upstream of the nozzle portion within the through hole does not
have a significant influence on the TOR.
[0110] In one embodiment, the length of the nozzle portion
influences the geometric standard deviation (GSD) of the droplet
size distribution of the aminoglycoside pharmaceutical formulation.
Low GSDs characterize a narrow droplet size distribution
(homogeneously sized droplets), which is advantageous for targeting
aerosol to the respiratory system, for example for the treatment of
bacterial infections (e.g., Pseudomonas or Mycobacteria) in cystic
fibrosis patients, or the treatment of nontuberculosis
mycobacteria, bronchiectasis (e.g., the treatment of cystic
fibrosis or non- cystic fibrosis patients), Pseudomonas or
Mycobacteria in patients. That is, the longer the nozzle portion
the lower the GSD. The average droplet size, in one embodiment is
less than 5 .mu.m, and has a GSD in a range of 1.0 to 2.2, or about
1.0 to about 2.2, or 1.5 to 2.2, or about 1.5 to about 2.2.
[0111] In one embodiment, as provided above, the system provided
herein comprises a nebulizer which generates an aerosol of the
aminoglycoside pharmaceutical formulation at a rate greater than
about 0.53 g per minute, or greater than about 0.55 g per minute.
In a further embodiment, the nebulizer comprises a vibratable
membrane having a first side for being in contact with the fluid
and an opposite second side, from which the droplets emerge.
[0112] The membrane, e.g., a stainless steel membrane, may be
vibrated by means of a piezoelectric actuator or any other suitable
means. The membrane has a plurality of through holes penetrating
the membrane in an extension direction from the first side to the
second side. The through holes may be formed as previously
mentioned by a laser source, electroforming or any other suitable
process. When the membrane is vibrating, the aminoglycoside
pharmaceutical formulation passes the through holes from the first
side to the second side to generate the aerosol at the second side.
Each of the through holes, in one embodiment, comprises an entrance
opening and an exit opening. In a further embodiment, each of the
through holes comprises a nozzle portion extending from the exit
opening over a portion of the through holes towards the entrance
opening. The nozzle portion is defined by the continuous portion of
the through hole in the extension direction comprising a smallest
diameter of the through hole and bordered by a larger diameter of
the through hole. In one embodiment, the larger diameter of the
through hole is defined as that diameter that is closest to 3
times, about 3 times, 2 times, about 2 times, 1.5 times, or about
1.5 times, the smallest diameter.
[0113] The smallest diameter of the through hole, in one
embodiment, is the diameter of the exit opening. In another
embodiment, the smallest diameter of the through hole is a diameter
about 0.5.times., about 0.6.times., about 0.7.times., about
0.8.times. or about 0.9.times. the diameter of the exit
opening.
[0114] In one embodiment, the nebulizer provided herein comprises
through holes in which the ratio of the total length of at least
one of the through holes in the extension direction to the length
of the respective nozzle portion of the through hole in the
extension direction is at least 4, or at least about 4, or at least
4.5, or at least about 4.5, or at least 5, or at least about 5, or
greater than about 5. In another embodiment, the nebulizer provided
herein comprises through holes in which the ratio of the total
length of the majority of through holes in the extension direction
to the length of the respective nozzle portion of the through holes
in the extension direction is at least 4, or at least about 4, or
at least 4.5, or at least about 4.5, or at least 5, or at least
about 5, or greater than about 5.
[0115] The extension ratios set forth above provide, in one
embodiment, an increased total output rate, as compared to
previously known nebulizers, and also provides a sufficient GSD.
The ratio configurations, in one embodiment, achieve shorter
application periods, leading to greater comfort for the patient and
effectiveness of the aminoglycoside compound. This is particularly
advantageous if the aminoglycoside compound in the formulation, due
to its properties, is prepared at a low concentration, and
therefore, a greater volume of the aminoglycoside pharmaceutical
formulation must be administered in an acceptable time, e.g., one
dosing session.
[0116] According to one embodiment, the nozzle portion terminates
flush with the second side. Therefore, the length of the nozzle
portion, in one embodiment, is defined as that portion starting
from the second side towards the first side up to and bordered by
the diameter that it is closest to about triple, about twice, about
2.5.times., or about 1.5.times. the smallest diameter. The smallest
diameter, in this embodiment, is the diameter of the exit
opening.
[0117] In one embodiment, the smallest diameter (i.e., one border
of the nozzle portion) is located at the end of the nozzle portion
in the extension direction adjacent to the second side. In one
embodiment, the larger diameter of the through hole, located at the
other border of the nozzle portion, is located upstream of the
smallest diameter in the direction in which the fluid passes the
plurality of through holes during operation.
[0118] According to one embodiment, the smallest diameter is
smaller than about 4.5 .mu.m, smaller than about 4.0 .mu.m, smaller
than about 3.5 .mu.m, or smaller than about 3.0 .mu.m.
[0119] In one embodiment, the total length of at least one through
hole in the extension direction is at least about 50 .mu.m, at
least about 60 .mu.m, at least about 70 .mu.m, or at least about 80
.mu.m. In a further embodiment, the total length of at least one of
the plurality of through holes is at least about 90 .mu.m. In one
embodiment, the total length of a majority of the plurality of
through holes in the extension direction is at least about 50
.mu.m, at least about 60 .mu.m, at least about 70 um, or at least
about 80 .mu.m. In a further embodiment, the total length of a
majority of the plurality of through holes is at least about 90
.mu.m.
[0120] The length of the nozzle portion, in one embodiment, is less
than about 25 .mu.m, less than about 20 .mu.m or less than about 15
.mu.m.
[0121] According to one embodiment, the through holes are
laser-drilled through holes formed in at least two stages, one
stage forming the nozzle portion and the remaining stage(s) forming
the remainder of the through holes.
[0122] In another embodiment, the manufacturing methods used lead
to a nozzle portion which is substantially cylindrical or conical
with a tolerance of less than +100% of the smallest diameter, less
than +75% of the smallest diameter, less than +50% of the smallest
diameter, less than +30% of the smallest diameter, less than +25%
of the smallest diameter, or less than +15% of the smallest
diameter.
[0123] Alternatively or additionally, the through holes are formed
in an electroforming process. In one embodiment, the through holes
have a first funnel-shaped portion at the first side and a second
funnel-shaped portion at the second side with the nozzle portion
in-between the first and the second funnel-shaped portions and
defined between the exit opening and the larger diameter. In this
instance, the total length of the through holes may as well be
defined by the distances from the first side to the exit opening
(smallest diameter) only.
[0124] In addition, the total output rate (TOR) may be further
increased by increasing the number of through holes provided in the
membrane. In one embodiment, an increase in number of through holes
is achieved by increasing the active perforated surface of the
membrane and maintaining the distance of the through holes relative
to each other at the same level. In another embodiment, the number
of through holes is increased by reducing the distance of the
through holes relative to each other and maintaining the active
area of the membrane. In addition, a combination of the above
strategies may be used.
[0125] In one embodiment, the total output rate of the nebulizer
described herein is increased by increasing the density of through
holes in the membrane. In one embodiment, the average distance
between through holes is about 70 .mu.m, or about 60 .mu.m, or
about 50 .mu.m.
[0126] In one embodiment, the membrane comprises between about 200
and about 8,000 through holes, between about 1,000 and about 6,000
through holes, between about 2,000 and about 5,000 through holes or
about 2,000 and about 4,000 through holes. In one embodiment, the
number of through holes described above increases the TOR, and the
TOR is increased regardless of whether the nozzle parameters are
implemented as described above. In one embodiment, the nebulizer
provided herein comprises about 3,000 through holes. In a further
embodiment, the through holes are located in a hexagonal array,
e.g., at about the center of the membrane (e.g., stainless steel
membrane). In a further embodiment, the average distance between
through holes is about 70 .mu.m.
[0127] FIG. 3 shows an aerosol generator (nebulizer) as disclosed
in WO 2001/032246, which is hereby incorporated by reference in its
entirety. The aerosol generator comprises a fluid reservoir 21 to
contain the pharmaceutical formulation, to be emitted into the
mixing chamber 3 in the form of an aerosol and to be inhaled by
means of the mouth piece 4 through the opening 41.
[0128] The aerosol generator comprises a vibratable membrane 22
vibrated by means of a piezoelectric actuator 23. The vibratable
membrane 22 has a first side 24 facing the fluid container 21 and a
second opposite side 25 facing the mixing chamber 3. In use, the
first side 24 of the vibratable membrane 22 is in contact with the
fluid contained in the fluid container 21. A plurality of through
holes 26 penetrating the membrane from the first side 24 to the
second side 25 are provided in the membrane 22. In use, the fluid
passes from the fluid container 21 through the through holes 26
from the first 24 to the second side 25 when the membrane 22 is
vibrated for generating the aerosol at the second side 25 and
emitting it into the mixing chamber 3. This aerosol may then be
drawn by inhalation of a patient from the mixing chamber 3 via the
mouth piece 4 and its inhalation opening 41.
[0129] FIG. 5 shows a cross-sectional computed tomography scan
showing three of the through holes 26 of such a vibratable membrane
22. The through holes 26 of this particular embodiment are formed
by laser drilling using three stages of different process
parameters, respectively. In a first stage, the portion 30 is
formed. In a second stage the portion 31 is formed and in a third
stage the nozzle portion 32 is formed. In this particular
embodiment, the length of the nozzle portion 32 is about 26 .mu.m,
whereas the portion 31 has a length of about 51 .mu.m. The first
portion 30 has a length of about 24.5 .mu.m. As a result, the total
length of each through hole is the sum of the length of the portion
30, the portion 31 and the nozzle portion 32, that is in this
particular example, about 101.5 .mu.m. Thus, the ratio of the total
length of each through hole 26 in the extension direction E to the
length of a respective one of the nozzle portions 32 in the
extension direction E is approximately 3.9.
[0130] In the embodiment in FIG. 6, the first portion 30 has a
length of about 27 .mu.m, the portion 31a length of about 55 .mu.m
and a nozzle portion a length of about 19 .mu.m. As a result, the
total length of the through hole 26 is about 101 .mu.m. Thus, the
ratio of the total length of the through hole 26 to the length of
the corresponding nozzle portion 32 in this embodiment is
approximately 5.3.
[0131] Both the vibratable membranes in FIGS. 5 and 6 were
manufactured with 6,000 through holes 26. The below table (Table 3)
indicates the mass median diameter (MMD), as determined by laser
diffraction, of the particles emitted at the second side of the
membrane, the time required for completely emitting a certain
amount of liquid (Nebulization time) as well as the TOR. The tests
were performed with a liposomal formulation of amikacin.
TABLE-US-00007 TABLE 3 Properties of nebulizer membranes. # of MMD
Nebulization TOR through Membrane (.mu.m) time (min) (g/min.) holes
26 1 (shown in FIG. 5 with a 4.2 14.6 0.57 6,000 nozzle portion of
26 .mu.m) 2 (shown in FIG. 6 with a 4.3 9.3 0.89 6,000 nozzle
portion of 19 .mu.m) 3 (similar to FIG. 6) 4.4 13.4 0.62 3,000 4
(similar to FIG. 6, 4.4 11.9 0.7 3,000 nozzle shorter than membrane
3)
[0132] Table 3 shows that the membrane 2 with the shorter nozzle
portion provides for an increased TOR and a reduced nebulization
time by 5.3 minutes, which is approximately 36% less as compared to
the membrane 1. Table 3 also shows that the MMD did not vary
significantly for each membrane tested. This is in contrast to the
differences in TOR observed for each membrane. Thus, in one
embodiment, the nebulization time for the nebulizer described
herein is reduced significantly as compared to prior art
nebulizers, without affecting the droplet size, as measured by
MMD.
[0133] In addition to the membrane shown in FIGS. 5 and 6,
membranes were manufactured having the nozzle portion further
reduced, and with 3,000 through holes 26 (membranes 3 and 4, Table
3). In particular, a membrane 3 was laser-drilled with a shorter
nozzle portion, whereas membrane 4 was manufactured using a shorter
nozzle portion than membrane 3. Table 3 indicates that even with
3,000 holes (membrane 3 and 4) a reduction in the length of the
nozzle portion results in an increased TOR compared to membrane 1
with 6,000 holes. The comparison of the membrane 3 and 4 as
compared to the membrane 2 further shows that a combination of a
higher number of holes (6,000 as compared to 3,000) and a reduced
length of the nozzle portion increases the TOR for the
nebulizer.
[0134] In one embodiment, it is advantageous to use a laser
drilling process as compared to electroforming for manufacturing
the through holes. The through holes shown in FIGS. 5 and 6,
manufactured by laser drilling, are substantially cylindrical or
conical as compared to the funnel-shaped entrance and exit of
electro-formed through holes, e.g., as disclosed in WO 01/18280.
The vibration of the membrane, that is its vibration velocity, may
be transferred to the pharmaceutical formulation over a larger area
by means of friction when the through holes are substantially
cylindrical or conical as compared to the funnel-shaped entrance
and exit of electro-formed through holes. The pharmaceutical
formulation, because of its own inertia, is then ejected from the
exit openings of the through holes resulting in liquid jets
collapsing to form the aerosol. Without wishing to be bound by
theory, it is thought that because an electro-formed membrane
comprises extremely bent surfaces of the through holes, the surface
or area for transferring the energy from the membrane to the liquid
is reduced.
[0135] However, the present invention may also be implemented in
electro-formed membranes, wherein the nozzle portion is defined by
the continuous portion of the through hole in the extension
direction starting from the smallest diameter of the through hole
towards the first side until it reaches a diameter 2.times. or
3.times. of the smallest diameter of the hole. In one embodiment,
the total length of the through hole is measured from the smallest
diameter to the first side.
[0136] Referring again to FIG. 1, so that the patient does not have
to remove or to put down the therapeutic device from his mouth
after inhaling the aerosol, the mouthpiece 3 has an opening 6
sealed by an elastic valve element 7 (exhalation valve). If the
patient exhales into the mouthpiece 3 and hence into the nebulizing
chamber 2, the elastic valve element 7 opens so that the exhaled
air is able to escape from the interior of the therapeutic aerosol.
On inhalation, ambient air flows through the nebulizing chamber 2.
The nebulizing chamber 2 has an opening sealed (not shown) by a
further elastic valve element (inhalation valve). If the patient
inhales through the mouthpiece 3 and sucks from the nebulizing
chamber 2, the elastic valve element opens so that the ambient air
is able to enter into the nebulizing chamber and mixed with the
aerosol and leave the interior of the nebulizing chamber 2 to be
inhaled. Further description of this process is provided in U.S.
Pat. No. 6,962,151, which is incorporated by reference in its
entirety for all purposes.
[0137] The nebulizer shown in FIG. 2 comprises a cylindrical
storage vessel 10 to supply a liquid that is fed to the membrane 5.
As shown in FIG. 2, the oscillating membrane 5 may be arranged in
an end wall 12 of the cylindrical liquid reservoir 10 to ensure
that the liquid poured into the liquid reservoir comes into direct
contact with the membrane 5 when the aerosol generator is held in
the position shown in FIG. 1. However, other methods may also be
used to feed the liquid to the oscillating membrane without any
change being necessary to the design of the device according to the
invention for the generation of a negative pressure in the liquid
reservoir.
[0138] On the side facing the end wall 12, the cylindrical liquid
container 10 is open. The opening is used to pour the liquid into
the liquid reservoir 10. Slightly below the opening on the external
surface 13 of the peripheral wall 14 there is a projection 15 which
serves as a support when the liquid container is inserted in an
appropriately embodied opening in a housing 35.
[0139] The open end of the liquid container 10 is closed by a
flexible sealing element 16. The sealing element 16 lies on the end
of the peripheral wall 14 of the liquid container 10 and extends in
a pot-shaped way into the interior of the liquid container 10
whereby a conically running wall section 17 is formed in the
sealing element 16 and closed off by a flat wall section 18 of the
sealing element 16. As discussed further below, forces act via the
flat wall section 18 on the sealing element 16 and so in one
embodiment the flat wall section 18 is thicker than the other
sections of the sealing element 16. On the perimeter of the flat
wall section 18, there is a distance to the conical wall section 17
so that the conical wall section 17 may be folded when the flat
wall section 18 is moved upwards, relative to the representation in
FIG. 2.
[0140] On the side of the flat wall section 18 facing away from the
interior of the liquid container, there is a projection comprising
a truncated cone section 19 and a cylindrical section 20. This
design enables the projection to be introduced and latched into an
opening adapted to match the cylindrical section since the flexible
material of the sealing element 16 permits the deformation of the
truncated cone section 19.
[0141] In one embodiment, the aerosol generator 4 comprises a
slidable sleeve 21 equipped with an opening of this type which is
substantially a hollow cylinder open on one side. The opening for
the attachment of the sealing element 16 is embodied in an end wall
of the slidable sleeve 21. When the truncated cone 19 has latched
into place, the end wall of the slidable sleeve 21 containing the
opening lies on the flat sealing element wall section 18. The
latching of the truncated cone 19 into the slidable sleeve enables
forces to be transmitted from the slidable sleeve 21 onto the flat
wall section 18 of the sealing element 16 so that the sealing
section 18 follows the movements of the slidable sleeve 21 in the
direction of the central longitudinal axis of the liquid container
10.
[0142] In a generalized form, the slidable sleeve 21 may be seen as
a slidable element, which may, for example, also be implemented as
a slidable rod which may be stuck-on or inserted in a drill hole.
Characteristic of the slidable element 21 is the fact that it may
be used to apply a substantially linearly directed force onto the
flat wall element 18 of the sealing element 16. Overall, the
decisive factor for the mode of operation of the aerosol generator
according to the invention is the fact that a slidable element
transmits a linear movement onto the sealing element so that an
increase in volume occurs within the liquid reservoir 10. Since the
liquid reservoir 10 is otherwise gas-tight, this causes a negative
pressure to be generated in the liquid reservoir 10.
[0143] The sealing element 16 and the slidable element 21 may be
produced in one piece, i.e., in one operation, but from different
materials. The production technology for this is available so that
a one-piece component for the nebulizer is created, e.g., in a
fully automatic production step.
[0144] In one embodiment, the slidable sleeve 21 is open on the end
facing the drill hole for the truncated cone but at least two
diametrically opposite lugs 22 and 23 protrude radially into the
interior of the slidable sleeve 21. A collar 24 encircling the
slidable sleeve extends radially outwards. While the collar 24 is
used as a support for the slidable sleeve 21 in the position shown
in FIG. 5, the projections 22 and 23 protruding into the interior
of the slidable sleeve 21 are used to absorb the forces acting on
the slidable sleeve 21 in particular parallel to the central
longitudinal axis. In one embodiment, these forces are generated by
means of two spiral grooves 25 which are located on the outside of
the peripheral wall of a rotary sleeve 26.
[0145] In one embodiment, the nebulizer may be implemented with one
of the projections 22 or 23 and one groove 25. In a further
embodiment, a uniformly distributed arrangement of two or more
projections and a corresponding number of grooves is provided.
[0146] In one embodiment, the rotary sleeve 26 is also a cylinder
open on one side whereby the open end is arranged in the slidable
sleeve 21 and is hence facing the truncated cone 19 enabling the
truncated cone 19 to penetrate the rotary sleeve 26. In addition,
the rotary sleeve 26 is arranged in the slidable sleeve 21 in such
a way that the projections 22 and 23 lie in the spiral grooves 25.
The inclination of the spiral groove 25 is designed so that, when
the rotary sleeve 26 is rotated in relation to the slidable sleeve
21, the projections 22 and 23 slide along the spiral grooves 25
causing a force directed parallel to the central longitudinal axis
to be exerted on the sliding projections 22 and 23 and hence on the
slidable sleeve 21. This force displaces the slidable sleeve 21 in
the direction of the central longitudinal axis so that the sealing
element 16 which is latched into the slidable sleeve's drill hole
by means of the truncated cone is also substantially displaced
parallel to the central longitudinal axis.
[0147] The displacement of the sealing element 16 in the direction
of the central longitudinal axis of the liquid container 10
generates a negative pressure in the liquid container 10,
determined inter alia by the distance by which the slidable sleeve
21 is displaced in the direction of the central longitudinal axis.
The displacement causes the initial volume V.sub.RI of the
gas-tight liquid container 10 to increase to the volume V.sub.RN
and thereby a negative pressure to be generated. The displacement
is in turn defined by the design of the spiral grooves 25 in the
rotary sleeve 26. In this way, the aerosol generator according to
the invention ensures that the negative pressure in the liquid
reservoir 10 may be generated in the relevant areas by means of
simple structural measures.
[0148] To ensure that the forces to be applied to generate the
negative pressure when handling the device remain low, the rotary
sleeve 26 is embodied in one piece with a handle 27 whose size is
selected to enable the user to rotate the handle 27, and hence the
rotary sleeve 26, manually without great effort. The handle 27
substantially has the shape of a flat cylinder or truncated cone
which is open on one side so that a peripheral gripping area 28 is
formed on the external periphery of the handle 27 which is touched
by the user's hand to turn the handle 27.
[0149] Due to the design of the spiral grooves 25 and the overall
comparatively short distance to be travelled by the slidable sleeve
21 in the longitudinal direction to generate a sufficient negative
pressure, in one embodiment, it is sufficient to turn the handle 27
and hence the rotary sleeve 26 through a comparatively small angle
of rotation. In one embodiment, the angle of rotation lies within a
range from 45 to 360 degrees. This embodiment allows for the ease
of handling of the device according to the invention and the
therapeutic aerosol generator equipped therewith.
[0150] In order to create a unit which may be operated simply and
uniformly from the slidable sleeve 21 and the rotary sleeve 26
including the handle 27, in one embodiment, the aerosol generator
described here has a bearing sleeve 29 for bearing the slidable
sleeve 21, which substantially comprises a flat cylinder open on
one side. The diameter of the peripheral wall 30 of the bearing
sleeve 29 is smaller than the internal diameter of the handle 27
and, in the example of an embodiment described, is aligned on the
internal diameter of a cylindrical latching ring 31 which is
provided concentrically to the gripping area 28 of the handle 27
but with a smaller diameter on the side of the handle 27 on which
the rotary sleeve 26 is also arranged. Embodied on the side of the
cylindrical latching ring 31 facing the rotary sleeve is a
peripheral latching edge 32 which may be brought into engagement
with latching lugs 33 situated at intervals on the peripheral wall
30 of the bearing sleeve 29. This allows the handle 27 to be
located on the bearing sleeve 29 whereby, as shown in FIG. 5, the
handle 27 is placed on the open end of the bearing sleeve 29 and
the latching edge 32 is interlatched with the latching lugs 33.
[0151] To hold the slidable sleeve 21, an opening is provided in
the centre of the sealed end of the bearing sleeve 29 in which the
slidable sleeve 21 is arranged, as may be identified in FIG. 2. The
collar 24 of the slidable sleeve 21 lies in the position shown in
FIG. 2 on the surface of the end wall of the bearing sleeve 29
facing the handle. Extending into the bearing opening are two
diametrically opposite projections 51 and 52, which protrude into
two longitudinal grooves 53 and 54 on the peripheral surface of the
slidable sleeve 21. The longitudinal grooves 53 and 54 run parallel
to the longitudinal axis of the slidable sleeve 21. The guide
projections 51 and 52 and the longitudinal grooves 53 and 54
provide anti-rotation locking for the slidable sleeve 21 so that
the rotational movement of the rotary sleeve 26 results not in
rotation but in the linear displacement of the slidable sleeve 21.
As is evident from FIG. 2, this ensures that the slidable sleeve 21
is held in the combination of the handle 27 and the bearing sleeve
29 in an axially displaceable way but locked against rotation. If
the handle 27 is rotated in relation to the bearing sleeve 29, the
rotary sleeve 26 also rotates in relation to the slidable sleeve 21
whereby the sliding projections 22 and 23 move along the spiral
grooves 25. This causes the slidable sleeve 21 to be displaced in
an axial direction in the opening of the bearing sleeve 29.
[0152] It is possible to dispense with the guide projections 51 and
52 in the bearing opening and the longitudinal grooves 53 and 54 in
the slidable sleeve 21. In one embodiment, the guide projections 51
and 52 and the longitudinal grooves 53 and 54 are not present in
the aerosol generator, and the truncated cone 19, the cylinder
sections 20 of the sealing elements 16 and the large-area support
for the slidable sleeve 21 holding the truncated cone on the flat
sealing element section 18 achieves anti-rotation locking of the
slidable sleeve 21 by means of friction. In a further embodiment,
the sealing element 16 is fixed so it is unable to rotate in
relation to the bearing sleeve 29.
[0153] In one embodiment, provided on the surface of the sealed end
of the bearing sleeve 19 facing away from the handle, is an annular
first sealing lip 34 concentric to the opening holding the slidable
sleeve. The diameter of the first sealing lip 34 corresponds to the
diameter of the peripheral wall 14 of the liquid container 10. As
provided in FIG. 2, this ensures that the first sealing lip 34
presses the sealing element 16 on the end of the peripheral wall
against the liquid reservoir 10 in such a way that the liquid
reservoir 10 is sealed. In addition, the first sealing lip 34 may
also fix the sealing element 16 so that it is unable to rotate in
relation to the liquid reservoir 10 and the bearing sleeve 29. In
one embodiment, excessive force need not be applied in order to
ensure that the aforesaid components of the device are unable to
rotate in relation to each other.
[0154] In one embodiment, the forces required are generated at
least to some extent by means of an interaction between the handle
27 and the housing 35 in which the pharmaceutical formulation
reservoir is embodied as one piece or in which the pharmaceutical
formulation (liquid) reservoir 10 is inserted as shown in FIG. 2.
In this case, the pharmaceutical formulation reservoir 10 inserted
in the casing with the peripheral projection 15 lies at intervals
on a support 36 in the housing 35 which extends radially into the
interior of the housing 35. This allows the liquid reservoir 10 to
be easily removed from the housing 35 for purposes of cleaning. In
the embodiment shown in FIG. 2, support is only provided at
intervals, and therefore, openings are provided for ambient air
when the patient inhales, described in more detail below.
[0155] Identifiable in FIG. 2 is the rotary lock, which is
implemented by means of the handle 27 on the one hand and the
housing 35 on the other. Shown are the locking projections 62 and
63 on the housing 35. However, there are no special requirements
with regard to the design of the rotary lock as far as the device
according to invention is concerned for the generation of the
negative pressure in the liquid reservoir 10.
[0156] In one embodiment, the liquid reservoir 10 is configured to
have a volume V.sub.RN of at least at least 16 mL, at least about
16 mL, at least 18 mL, at least about 18 mL, at least 20 mL or at
least about 20 mL so that when for example, an amount of 8 mL of
liquid (e.g., aminoglycoside pharmaceutical formulation) to be
emitted in the form of an aerosol is contained in (filled or poured
into) the liquid reservoir 10, an air cushion of 8 mL or about 8 mL
is provided. That is, the ratio of the volume V.sub.RN to the
initial volume of liquid V.sub.L within the liquid reservoir 10 is
at least 2.0 and the ratio between the volume V.sub.A of a gas and
V.sub.L of the liquid is at least 1.0. It has been shown that a
liquid reservoir having a volume V.sub.RN of about 15.5 mL, about
19.5 mL and about 22.5 mL are efficient, and that efficiency
increases with the increase in V.sub.RN.
[0157] In one embodiment, the ratio between V.sub.RN and V.sub.L is
at least 2.0, at least about 2.0, at least 2.4, at least about 2.4,
at least 2.8 or at least about 2.8. In one embodiment, the ratio
between V.sub.A and V.sub.L is at least 1.0, at least 1.2, at least
1.4, at least 1.6 or at least 1.8. In another embodiment, the ratio
between V.sub.A and V.sub.L is at least about 1.0, at least about
1.2, at least about 1.4, at least about 1.6 or at least about
1.8.
[0158] The volume of the air cushion, in one embodiment, is at
least 2 mL, at least about 2 mL, at least 4 mL, at least about 4
mL, is at least 6 mL, at least about 6 mL, at least 8 mL, at least
about 8 mL, at least 10 mL, at least about 10 mL, at least 11 mL,
at least about 11 mL, at least 12 mL, at least about 12 mL, at
least 13 mL, at least about 13 mL, at least 14 mL or at least about
14 mL. In one embodiment, the volume of the air cushion is at least
about 11 mL or at least about 14 mL. In one embodiment, the volume
of the air cushion is from about 6 mL to about 15 mL, and the ratio
between V.sub.RN and V.sub.L is at least about 2.0 to at least
about 3.0. In a further embodiment, the between V.sub.RN and
V.sub.L is at least about 2.0 to about at least about 2.8.
[0159] The volume of the air cushion, in one embodiment, is about 2
mL, about 4 mL, about 6 mL, about 8 mL, about 10 mL, about 11 mL,
about 12 mL, about 13 mL, or about 14 mL.
[0160] In one embodiment, the ratio of the volume V.sub.RN to the
initial volume of liquid V.sub.L is at least 2.0. Theoretically an
unlimited enlargement of the increased volume V.sub.RN of the
liquid reservoir 10 will result in a nearly stable negative
pressure range. In one embodiment, the ratio of the volume V.sub.RN
to the initial volume of liquid V.sub.L is within the range between
2.0 and 4.0 and in a further embodiment is between 2.4 and 3.2. Two
examples of the ratio ranges (V.sub.RN/V.sub.L) for different
initial volume of liquid V.sub.L between 4 mL and 8 mL are given in
Table 4, below.
TABLE-US-00008 TABLE 4 Nebulizer Reservoir specifications V.sub.L
V.sub.RN Ratio (V.sub.RN/V.sub.L) 4 mL 8.0-16.0 2.0-4.0 4 mL
9.5-12.8 2.4-3.2 5 mL 10.0-20.0 2.0-4.0 5 mL 12.0-16.0 2.4-3.2 6 mL
12.0-24.0 2.0-4.0 6 mL 14.5-19.2 2.4-3.2 8 mL 16.0-32.0 2.0-4.0 8
mL 19.5-25.6 2.4-3.2
[0161] The systems provided herein may be used to treat a variety
of pulmonary infections in subjects in need thereof. Among the
pulmonary infections (such as in cystic fibrosis patients) that can
be treated with the methods of the invention are gram negative
infections. In one embodiment, infections caused by the following
bacteria are treatable with the systems and formulations provided
herein: Pseudomonas (e.g., P. aeruginosa, P. paucimobilis, P.
putida, P. fluorescens, and P. acidovorans), Burkholderia (e.g., B.
pseudomallei, B. cepacia, B. cepacia complex, B. dolosa, B.
fungorum, B. gladioli, B. multivorans, B. vietnamiensis, B.
pseudomallei, B. ambifaria, B. andropogonis, B. anthina, B.
brasilensis, B. caledonica, B. caribensis, B. caryophylli),
Staphylococcus (e.g., S. aureus, S. auricularis, S. carnosus, S.
epidermidis, S. lugdunensis), Methicillin-resistant Staphylococcus
aureus (MRSA), Streptococcus (e.g., Streptococcus pneumoniae),
Escherichia coli, Klebsiella, Enterobacter, Serratia, Haemophilus,
Yersinia pestis, Mycobacterium, nontuberculous mycobacterium (e.g.,
M avium, M. avium subsp. hominissuis (MAH), M abscessus, M.
chelonae, M. bolletii, M. kansasii, M ulcerans, M. avium, M avium
complex (MAC) (M. avium and M. intracellulare), M conspicuum, M.
kansasii, M peregrinum, M. immunogenum, M. xenopi, M marinum, M.
malmoense, M marinum, M mucogenicum, M nonchromogenicum, M.
scrofulaceum, M simiae, M smegmatis, M szulgai, M terrae, M terrae
complex, M haemophilum, M. genavense, M. asiaticum, M shimoidei, M
gordonae, M. nonchromogenicum, M triplex, M lentiflavum, M celatum,
M. fortuitum, M. fortuitum complex (M. fortuitum and M
chelonae)).
[0162] In one embodiment, the systems described herein are used to
treat an infection caused by a nontuberculous mycobacterial
infection. In one embodiment, the systems described herein are used
to treat an infection caused by Pseudomonas aeruginosa,
Mycobacterium abscessus, Mycobaterium avium or M avium complex. In
a further embodiment, a patient with cystic fibrosis is treated for
a Pseudomonas aeruginosa, Mycobacterium abscessus, Mycobaterium
avium, or Mycobaterium avium complex infection with one or more of
the systems described herein. In even a further embodiment, the
Mycobaterium avium infection is Mycobacterium avium subsp.
hominissuis.
[0163] In one embodiment, a patient with cystic fibrosis is treated
for a pulmonary infection with one of the systems provided herein.
In a further embodiment, the pulmonary infection is a Pseudomonas
infection. In yet a further embodiment, the Pseudomonas infection
is P. aeruginosa. In a further embodiment, the aminoglycoside in
the system is amikacin.
[0164] In one embodiment, the system provided herein is used for
the treatment or prophylaxis of Pseudomonas aeruginosa,
Mycobacterium abscessus, Mycobaterium avium or Mycobaterium avium
complex lung infection in a cystic fibrosis patient or a non-cystic
fibrosis patient. In a further embodiment, the system provided
herein comprises a liposomal aminoglycoside formulation. In a
further embodiment, the aminoglycoside is selected from amikacin,
apramycin, arbekacin, astromicin, capreomycin, dibekacin,
framycetin, gentamicin, hygromycin B, isepamicin, kanamycin,
neomycin, netilmicin, paromomycin, rhodestreptomycin, ribostamycin,
sisomicin, spectinomycin, streptomycin, tobramycin, verdamicin or a
combination thereof. In even a further embodiment, the
aminoglycoside is amikacin, e.g., amikacin sulfate.
[0165] An obstacle to treating infectious diseases such as
Pseudomonas aeruginosa, the leading cause of chronic illness in
cystic fibrosis patients is drug penetration within the
sputum/biofilm barrier on epithelial cells (FIG. 7). In FIG. 7, the
donut shapes represent liposomal/complexed aminoglycoside, the "+"
symbol represents free aminoglycoside, the "-" symbol mucin,
alginate and DNA, and the solid bar symbol represents Pseudomonas
aeruginosa. This barrier comprises both colonized and planktonic P.
aeruginosa embedded in alginate or exopolysaccharides from
bacteria, as well as DNA from damaged leukocytes, and mucin from
lung epithelial cells, all possessing a net negative charge. The
negative charge binds up and prevents penetration of positively
charged drugs such as aminoglycosides, rendering them biologically
ineffective (Mendelman et al., 1985). Without wishing to be bound
by theory, entrapment of aminoglycosides within liposomes or lipid
complexes shields or partially shields the aminoglycosides from
non-specific binding to the sputum/biofilm, allowing for liposomes
or lipid complexes (with entrapped aminoglycoside) to penetrate
(FIG. 7).
[0166] In another embodiment, a patient is treated for
nontuberculous mycobacteria lung infection with one of the systems
provided herein. In a further embodiment, the system provided
herein comprises a liposomal amikacin formulation.
[0167] In another embodiment, the system provided herein is used
for the treatment or prophylaxis of one or more bacterial
infections in a cystic fibrosis patient. In a further embodiment,
the system provided herein comprises a liposomal aminoglycoside
formulation. In a further embodiment, the aminoglycoside is
amikacin.
[0168] In another embodiment, the system provided herein is used
for the treatment or prophylaxis of one or more bacterial
infections in a patient with bronchiectasis. In a further
embodiment, the system provided herein comprises a liposomal
aminoglycoside formulation. In a further embodiment, the
aminoglycoside is amikacin or amikacin sulfate.
[0169] In yet another embodiment, the system provided herein is
used for the treatment or prophylaxis of Pseudomonas aeruginosa
lung infections in non-CF bronchiectasis patients. In a further
embodiment, the system provided herein comprises a liposomal
aminoglycoside formulation. In a further embodiment, the
aminoglycoside is amikacin.
[0170] As provided herein, the present invention provides
aminoglycoside formulations administered via inhalation. In one
embodiment, the MMAD of the aerosol is about 3.2 .mu.m to about 4.2
.mu.m, as measured by the Anderson Cascade Impactor (ACI), or about
4.4 .mu.m to about 4.9 .mu.m, as measured by the Next Generation
Impactor (NGI).
[0171] In one embodiment, the nebulization time of an effective
amount of an aminoglycoside formulation provided herein is less
than 20 minutes, less than 18 minutes, less than 16 minutes or less
than 15 minutes. In one embodiment, the nebulization time of an
effective amount of an aminoglycoside formulation provided herein
is less than 15 minutes or less than 13 minutes. In one embodiment,
the nebulization time of an effective amount of an aminoglycoside
formulation provided herein is about 13 minutes.
[0172] In one embodiment, the formulation described herein is
administered once daily to a patient in need thereof.
EXAMPLES
[0173] The present invention is further illustrated by reference to
the following Examples. However, it should be noted that these
Examples, like the embodiments described above, are illustrative
and are not to be construed as restricting the scope of the
invention in any way.
Example 1
Comparison Of Nebulizer Reservoir Volumes
[0174] In this example, the aerosol generator was an
investigational eFlow.RTM. nebulizer, modified for use with
liposomal aminoglycoside formulations provided herein, of Pari
Pharma GmbH, Germany. A first aerosol generator had an initial
volume of the liquid reservoir V.sub.RI of 13 mL (A), a second one
of 17 mL (B), a third one of 22 mL (C) and a fourth one of 20 mL
(D). That is the increased volume V.sub.RN of the first one had
15.5 mL, the second one 19.5 mL, the third 24.5 mL and the fourth
22.5 mL.
[0175] 8 mL of a liposomal amikacin formulation was poured into the
liquid reservoir 10. As shown in FIG. 8, an air cushion of 8 mL
resulted in an aerosol generation time period upon complete
emission of 8 mL of the formulation in the liquid reservoir of
between 14 and 16 minutes. An air cushion of 12 mL, however,
decreased the aerosol generation time to a range between 12 and
approximately 13 minutes. The air cushion of 17 mL further
decreases the aerosol generation time to an amount between 10 and
12 minutes (FIG. 6).
[0176] Further, the first (A) and third (C) version of the aerosol
generator had been used together with 8 mL of the liposomal
amikacin formulation. An initial negative pressure of equal to or
less than 50 mbar was generated within the liquid reservoir. In
addition, the negative pressure was measured during the aerosol
generation and is shown over the aerosol generation time in FIG. 9.
In other words, FIG. 9 shows experimental data comparing the
negative pressure range during the aerosol generation time for a
liquid reservoir (C) having a volume V.sub.RN of 24.5 mL and a
liquid reservoir (A) having a volume V.sub.RN of 15.5 mL. The
initial amount of amikacin formulation V.sub.L was 8 mL and the
initial negative pressure was about 50 mbar. The graph indicates
that a larger air cushion prevents the negative pressure from
increasing above a critical value of 300 mbar.
[0177] The dependence of aerosol generator efficiency (proportional
to liquid output rate or total output rate) on different negative
pressures was measured with the nebulizer described above. A
liposomal amikacin formulation having a viscosity in the range of
5.5 to 14.5 mPa.times.s at sheer forces between 1.1 and 7.4 Pa
(thixotrope) was used in the experiment. As shown in FIG. 10, the
efficiency is optimum in a negative pressure range between 150 mbar
and 300 mbar. As also shown in FIG. 10, the efficiency decreases at
a negative pressure below approximately 150 mbar and at a negative
pressure of above 300 mbar.
[0178] Furthermore, the same liposomal amikacin formulation as in
FIG. 8 was used in four different aerosol generators based on the
modified eFlow.RTM., wherein the first aerosol generator (A) is a
modified eFlow.RTM. with an increased volume V.sub.RN of the liquid
reservoir of 19.5 mL and filled with 8 mL of the liposomal amikacin
formulation.
[0179] The second aerosol generator (B) had a reservoir with an
increased volume V.sub.RN of 16 mL filled with 8 mL of the
mentioned liposomal amikacin formulation, the third aerosol
generator (C) one had an increased volume V.sub.RN of 24.5 mL,
filled with 8 mL of the mentioned liquid. The fourth aerosol
generator had an increased volume V.sub.RN of the liquid reservoir
of 22.5 mL, and was filled with 8 mL of the aforementioned
liposomal amikacin formulation.
[0180] FIG. 11 shows experimental data of these four aerosol
generators filled with 8 mL of the liposomal amikacin formulation.
The results show the aerosol generation time for complete emission
of the liposomal amikacin formulation within the liquid reservoir
in relation to the ratio of the increased volume of the liquid
reservoir (V.sub.RN) to the initial volume of liquid in the liquid
reservoir before use (V.sub.L). FIG. 11 indicates that with the
modified aerosol generator device (A) an aerosol generation time of
approximately 16 minutes was required, whereas the aerosol
generation time decreased with an increased ratio V.sub.RN/V.sub.L.
The data also shows that the aerosol generation time could be
reduced by approximately 4 minutes to below 12 minutes with the
third aerosol generator device (C).
[0181] The data provided in Example 1 therefore indicates that a
larger air cushion enables the operation of the aerosol generator
for a longer time in an efficient negative pressure range so that
the total aerosol generation time may significantly be reduced.
Therefore, even large amounts of liquid such as 8 mL may be
nebulized (emitted in form of aerosol) in a period of time below 12
minutes.
Example 2
Aerosol Properties of Amikacin Formulation
[0182] Eleven different lots of the liposomal amikacin formulation
were examined with the modified eFlow.RTM. nebulizer (i.e.,
modified for use with the liposomal aminoglycoside formulations
described herein) having a modified 40 mesh membrane fabricated as
described herein, and a reservoir with an 8 mL liquid capacity and
aforementioned air cushion. Cascade impaction was performed using
either the ACI (Anderson Cascade Impactor) or the NGI (Next
Generation Impactor) to establish aerosol properties: mass median
aerodynamic diameter (MMAD), geometric standard deviation (GSD),
and Fine-Particle-Fraction (FPF). Mass Median Aerodynamic Diameter
(MMAD) measurement with ACI
[0183] An Anderson Cascade Impactor (ACI) was used for MMAD
measurements and the nebulization work was conducted inside a
ClimateZone chamber (Westech Instruments Inc., Ga.) to maintain
temperature and relative humanity % during nebulization. The
ClimateZone was pre-set to a temperature of 18.degree. C. and a
relative humanity of 50%. The ACI was assembled and loaded inside
the ClimateZone. A probe thermometer (VWR dual thermometer) was
attached to the surface of ACI at stage 3 to monitor the
temperature of ACI. Nebulization was started when the temperature
of the ACI reached 18.+-.0.5.degree. C.
[0184] With the 8 mL handsets loaded with 8 mL, it was found that
the ACI could not handle the whole 8 mL dose; i.e., amikacin
liposomal formulation deposited on ACI plate 3 overflowed. It was
determined that the percent drug distribution on each ACI stage was
not affected by the amount of liposomal amikacin formulation
collected inside the ACI as long as there was no liquid overflow at
ACI stage 3 (data not shown). Therefore for nebulization, the
nebulizer was either filled with 4 mL liposomal amikacin
formulation and nebulized until empty or filled with 8 mL of
liposomal amikacin formulation and nebulized for about 6 minutes of
collection time (i.e., .about.4 mL).
[0185] The nebulizate was collected at a flow rate of 28.3 L/min in
the ACI which was cooled to 18.degree. C. The nebulization time was
recorded and the nebulization rate calculated based on the
difference in weight (amount nebulized) divided by the time
interval.
[0186] After the nebulizate was collected, ACI collection plates 0,
1, 2, 3, 4, 5, 6 and 7 were removed, and each was loaded into its
own petri dish. An appropriate amount of extraction solution (20 mL
for plates 2, 3, and 4, and 10 mL for plates 0, 1, 5, 6, and 7) was
added to each Petri dish to dissolve the formulation deposited on
each plate. Samples from plates 0, 1, 2, 3, 4, 5 and 6 were further
diluted appropriately with mobile phase C for HPLC analysis. Sample
from plate 7 was directly analyzed by HPLC without any further
dilution. The ACI Filter was also transferred to a 20 mL vial and
10 mL extraction solution was added, and the capped vial vortexed
to dissolve any formulation deposited on it. Liquid samples from
the vial were filtered (0.2 jam) into HPLC vials for HPLC analysis.
The induction port with connector was also rinsed with 10 mL
extraction solution to dissolve the formulation deposited on it,
and the sample was collected and analyzed by HPLC with 2 time
dilution. Based on the amikacin amount deposited on each stage of
the impactor, mass median aerodynamic diameter (MMAD), geometric
standard deviation (GSD) and fine particle fraction (FPF) were
calculated.
[0187] In the cases for nebulizers loaded with 8 mL and nebulized
for 6 minutes fine particle dose (FPD) was normalized to the volume
of formulation nebulized in order to compare FPD across all
experiments. FPD (normalized to the volume of formulation
nebulized) was calculated according to the following equation:
FPD ( normalized to volume nebulized ) ( mg mL ) = Amikacin
Recovered ACI .times. FPF ( mg ) Arikace Nebulized ( g ) / Density
( g mL ) ##EQU00001##
Mass Median Aerodynamic Diameter (MMAD) measurement with NGI
[0188] A Next Generation Impactor (NGI) was also used for MMAD
measurements and the nebulization work was conducted inside a
ClimateZone chamber (Westech Instruments Inc., Ga.) to maintain
temperature and RH % during nebulization. The ClimateZone was
pre-set to a temperature of 18.degree. C. and a relative humanity
of 50%. The NGI was assembled and loaded inside the ClimateZone. A
probe thermometer (VWR dual thermometer) was attached to the
surface of NGI to monitor the temperature of NGI. Nebulization was
started when the temperature of the NGI reached 18.+-.0.5.degree.
C.
[0189] 8 mL of the liposomal amikacin formulation was added to the
nebulizer and nebulized. When there was no more aerosol observed,
the timer was stopped. The nebulizate was collected at a flow rate
of 15 L/min in the NGI which was cooled to 18.degree. C. The
nebulization time was recorded and the nebulization rate calculated
based on the difference in weight (amount nebulized) divided by the
time interval.
[0190] After aerosol collection was done, the NGI tray with tray
holder was removed from NGI. An appropriate amount of extraction
solution was added to NGI cups 1, 2, 3, 4, 5, 6, 7 and MOC to
dissolve the formulation deposited on these cups. This material was
transferred to a volumetric flask respectively. For NGI cups 1, 2,
and 6, 25 ml volumetric flasks were used; for NIG cups 2, 3, 4, 50
ml volumetric flasks were used. More extraction solution was added
to the cups and again transferred to the volumetric flask. This
procedure was repeated several times in order to transfer
formulation deposited on the NGI cup to the volumetric flask
completely. The volumetric flasks were topped up to bring the final
volume to either 25 ml or 50 ml and shaken well before sampled.
Samples from cups 1, 2, 3, 4, 5, 6 and 7 were further diluted
appropriately with mobile phase C for HPLC analysis. Sample from
MOC was directly analyzed by HPLC without any further dilution. The
NGI Filter was also transferred to a 20 mL vial and 10 mL
extraction solution was added, and the capped vial vortexed to
dissolve any formulation deposited on it. Liquid samples from the
vial were filtered (0.2 micron) into HPLC vials for HPLC analysis.
The Induction port with connector was also rinsed with 10 mL
extraction solution to dissolve the formulation deposited on it,
and the sample was collected and analyzed by HPLC with 11 time
dilution.
[0191] Based on the amikacin amount deposited on each stage of the
impactor, MMAD, GSD and FPF were calculated.
[0192] FPD was normalized to the volume of formulation nebulized in
order to compare FPD across all experiments. FPD (normalized to the
volume of formulation nebulized) was calculated according to the
following equation:
FPD ( normalized to volume nebulized ) ( mg mL ) = Amikacin
Recovered ACI .times. FPF ( mg ) Arikace Nebulized ( g ) / Density
( g mL ) ##EQU00002##
[0193] The results of these experiments are provided in FIGS. 12
and 13 and Table 5, below.
TABLE-US-00009 TABLE 5 Aerosol Characteristics ACI APSD Data NGI
APSD Data Nebulization Data Aerosol Neb. FPF <5 Aerosol Neb. FPF
<5 Aerosol Neb. % Assoc. Amikacin Head Rate MMAD .mu.m Head Rate
MMAD .mu.m Head Rate Amikacin Conc. Run ID (g/min) (.mu.m) GSD (%)
ID (g/min) (.mu.m) GSD (%) ID (g/min) Post-Neb 66.9 1 J 0.66 3.7
1.7 70.4 J 0.68 4.7 1.7 55.5 A 0.63 69.1 mg/mL 2 K 0.62 3.7 1.7
71.7 K 0.63 4.5 1.7 57.5 B 0.60 68.2 3 L 0.65 4.0 1.8 66.1 L 0.71
4.8 1.7 52.6 C 0.56 69.9 70.8 1 M 0.64 3.9 1.7 67.1 M 0.74 4.7 1.7
54.8 M 0.65 64.5 mg/mL 2 N 0.68 4.0 1.8 64.8 N 0.78 4.9 1.7 52.0 N
0.67 66.3 3 O 0.69 3.9 1.7 67.4 O 0.75 4.8 1.7 52.7 O 0.64 69.4
64.6 1 C 0.78 4.0 1.8 65.5 A 0.74 4.7 1.7 54.6 G 0.72 71.9 mg/mL 2
D 0.64 3.7 1.7 70.2 B 0.73 4.7 1.7 55.2 H 0.64 71.5 3 H 0.62 3.7
1.7 70.6 C 0.78 4.7 1.7 54.4 J 0.68 71.8 68.5 1 E 0.69 3.8 1.7 69.4
E 0.70 4.6 1.7 56.2 E 0.60 69.1 mg/mL 2 F 0.78 4.0 1.8 66.2 F 0.83
4.7 1.7 54.8 F 0.67 70.4 3 G 0.65 3.8 1.7 69.1 G 0.69 4.6 1.7 57.2
G 0.61 69.5 65.7 1 V 0.74 3.8 1.7 69.1 V 0.84 4.7 1.7 54.3 M 0.64
69.2 mg/mL 2 W 0.72 3.8 1.7 68.3 W 0.78 4.7 1.7 55.1 N 0.74 67.9 3
X 0.70 3.9 1.7 68.0 X 0.74 4.7 1.7 54.5 O 0.63 68.6 66.8 1 J 0.63
3.7 1.8 70.6 A 0.77 4.8 1.7 53.3 A 0.70 73.2 mg/mL 2 K 0.59 3.7 1.8
70.4 D 0.55 4.7 1.7 55.1 B 0.70 72.4 3 L 0.64 3.9 1.8 66.6 H 0.65
4.7 1.7 55.3 C 0.83 72.8 69.2 1 S 0.66 3.8 1.7 68.6 U 0.80 4.8 1.7
53.0 S 0.69 70.7 mg/mL 2 T 0.73 3.8 1.7 68.3 V 0.78 4.5 1.7 58.2 T
0.75 71.0 3 U 0.54 4.0 1.8 65.5 W 0.78 4.7 1.7 55.3 U 0.80 71.1
71.4 1 Q 0.66 3.8 1.7 68.4 M 0.75 4.6 1.7 56.7 P 0.71 72.4 mg/mL 2
R 0.71 3.9 1.8 66.6 N 0.78 4.8 1.7 52.9 Q 0.68 70.0 3 S 0.66 3.8
1.7 68.5 O 0.78 4.6 1.7 55.7 R 0.74 71.7 69.9 1 C 0.77 4.1 1.8 64.3
J 0.68 4.4 1.7 59.4 A 0.68 73.8 mg/mL 2 D 0.62 3.8 1.7 68.6 K 0.69
4.4 1.7 59.7 B 0.63 73.6 3 H 0.61 3.7 1.7 70.3 L 0.77 4.7 1.7 55.6
C 0.70 75.7 72.2 1 T 0.70 3.8 1.7 69.8 T 0.74 4.6 1.7 55.8 M 0.65
67.9 mg/mL 2 U 0.76 3.9 1.7 67.0 U 0.74 4.7 1.7 54.8 N 0.71 70.3 3
X 0.67 3.9 1.7 67.9 X 0.70 4.7 1.7 54.9 P 0.57 71.8 70.4 1 C 0.66
3.6 1.7 73.1 J 0.65 4.5 1.7 58.0 H 0.59 60.1 mg/mL 2 D 0.57 3.5 1.7
74.1 K 0.65 4.5 1.7 59.1 J 0.69 59.3 3 E 0.63 3.5 1.7 75.2 L 0.66
4.7 1.7 55.6 K 0.63 58.5
Example 3
Nebulization Rate Study
[0194] Nebulization rate studies (grams of formulation nebulized
per minute) were conducted in a biosafety cabinet (Model 1168, Type
B2, FORMA Scientific). The assembled nebulizer (handset with mouth
piece and aerosol head) was first weighed empty (W.sub.1), then a
certain volume of formulation was added and the nebulizer device
was weighed again (W.sub.2). The nebulizer and timer were started
and the formulations nebulized were collected in a chilled impinger
at a flow rate of .about.8 L/min (see FIG. 14 for details of
experimental setup). When there was no more aerosol observed, the
timer was stopped. The nebulizer was weighed again (W.sub.3), and
the time of nebulization (t) was recorded. Total formulation
nebulized was calculated as W.sub.2-W.sub.3 and total drug residue
after nebulization was calculated as W.sub.3-W.sub.1. The
nebulization rate of formulation was calculated according to the
following equation:
Nebulization Rate ( g min ) = W 2 - W 3 t ##EQU00003##
[0195] Nebulization rates in g/min., as well as other related
results, for liposomal amikacin nebulized using a nebulizer
fabricated according to the specification (twenty four aerosol
heads were selected and were used in these studies) are captured in
Table 6.
TABLE-US-00010 TABLE 6 Formulation nebulization rates (g/min)
Formulation Neb Aerosol Neb Time Nebulized Rate Run Head # (min)
(g) (g/min) 1 1 11.90 7.7346 0.65 2 2 11.58 8.0573 0.70 3 3 10.87
8.0029 0.74 4 4 13.63 7.9359 0.58 5 5 12.60 8.0577 0.64 6 6 12.62
8.0471 0.64 7 7 14.23 8.073 0.57 8 8 14.67 8.0872 0.55 9 9 13.58
7.9235 0.58 10 10 12.28 7.9649 0.65 11 11 12.33 8.1872 0.66 12 12
13.17 8.1694 0.62 13 1 11.22 7.9991 0.71 14 2 11.90 8.1392 0.68 15
3 12.17 8.0162 0.66 16 4 12.90 8.0174 0.62 17 5 11.22 7.893 0.70 18
6 10.23 8.0401 0.79 19 7 12.55 8.0988 0.65 20 8 14.88 7.8781 0.53
21 9 13.68 8.1678 0.60 22 10 12.33 8.2253 0.67 23 11 12.60 8.0783
0.64 24 12 11.83 7.946 0.67 25 1 11.92 8.1703 0.69 26 2 11.95
7.9837 0.67 27 3 13.63 8.1536 0.60 28 4 11.90 7.9376 0.67 29 5
12.27 8.1727 0.67 30 6 12.27 8.0875 0.66 31 7 13.65 8.0767 0.59 32
8 15.80 8.1183 0.51 33 9 13.65 8.1373 0.60 34 10 12.98 7.8864 0.61
35 11 11.63 8.1445 0.70 36 12 12.95 8.0232 0.62 37 13 12.80 7.9098
0.62 38 14 10.25 8.0328 0.78 39 15 12.13 7.9911 0.66 40 16 12.33
8.1756 0.66 41 17 12.47 7.9417 0.64 42 18 13.17 7.9046 0.60 43 19
13.92 7.5367 0.54 44 20 11.47 8.1466 0.71 45 21 11.67 7.9366 0.68
46 22 13.17 8.0613 0.61 47 23 12.77 7.8596 0.62 48 24 12.25 8.0552
0.66 49 13 13.67 7.9379 0.58 50 14 10.55 8.0221 0.76 51 15 11.80
8.0555 0.68 52 16 10.08 8.1639 0.81 53 17 11.08 7.9121 0.71 54 18
12.28 8.017 0.65 55 19 11.40 7.9415 0.70 56 20 12.17 8.211 0.67 57
21 11.45 8.18 0.71 58 22 12.03 7.8946 0.66 59 23 12.83 8.0771 0.63
60 24 11.97 7.9936 0.67 61 13 12.38 8.0054 0.65 62 14 10.53 8.0492
0.76 63 15 11.82 7.8161 0.66 64 16 11.83 8.1169 0.69 65 17 12.67
8.1778 0.65 66 18 12.03 8.2436 0.69 67 19 13.17 7.8821 0.60 68 20
12.17 8.2397 0.68 69 21 11.78 8.1814 0.69 70 22 11.78 8.3443 0.71
71 23 13.17 8.1699 0.62 72 24 11.50 8.0413 0.70 Average 12.4 .+-.
1.1 8.0 .+-. 0.1 0.66 .+-. 0.06
Example 4
Percent of Associate Amikacin Post-Nebulization and Nebulizate
Characterization
[0196] The free and liposomal complexed amikacin in the nebulizate
of Example 3 was measured. As mentioned in Example 3, the
nebulizate was collected in a chilled impinger at a flow rate of 8
L/min (FIG. 14).
[0197] The nebulizate collected in the impinger was rinsed with
1.5% NaCl and transferred to a 100 mL or 50-mL volumetric flask.
The impinger was then rinsed several times with 1.5% NaCl in order
to transfer all the formulation deposited in the impinger to the
flask. To measure the free amikacin concentration of the
nebulizate, 0.5 mL of the diluted nebulizate inside the volumetric
flask was taken and loaded to an Amicon.RTM. Ultra-0.5 mL 30K
centrifugal filter device (regenerated cellulose, 30K MWCO,
Millipore) and this device was centrifuged at 5000 G at 15.degree.
C. for 15 minutes. An appropriate amount of filtrate was taken and
was diluted 51 times with mobile phase C solution. Amikacin
concentration was determined by HPLC. To measure total amikacin
concentration of the nebulizate, an appropriate amount of the
diluted nebulizate inside the volumetric flask was taken and
diluted (also dissolved) 101 times in extraction solution
(perfluoropentanoic acid:1-propanol:water (25:225:250, v/v/v)) and
the amikacin concentration determined by HPLC.
[0198] The percent associated amikacin post-nebulization was
calculated by the following equation:
% Associated = Concentration Total - Concentration Free
Concentration Total .times. 100 ##EQU00004##
[0199] The percent associated amikacin post-nebulization and total
dose recovery from nebulization experiments described in Table 6
are summarized in Table 7. Corresponding nebulization rates were
also included in Table 7.
TABLE-US-00011 TABLE 7 Percent associated amikacin
post-nebulization and total dose recovered Aerosol % Recovered Neb
Rate Run Head # Associated % (g/min) 1 1 65.7 104 0.65 2 2 65.1 97
0.70 3 3 64.5 96 0.74 4 4 66.1 97 0.58 5 5 62.1 92 0.64 6 6 65.5 95
0.64 7 7 63.5 94 0.57 8 8 60.4 92 0.55 9 9 65.0 93 0.58 10 10 72.7
102 0.65 11 11 64.9 92 0.66 12 12 66.7 97 0.62 13 1 67.1 102 0.71
14 2 64.2 97 0.68 15 3 68.8 98 0.66 16 4 65.5 94 0.62 17 5 66.1 98
0.70 18 6 65.7 94 0.79 19 7 65.5 100 0.65 20 8 64.8 95 0.53 21 9
60.3 94 0.60 22 10 59.1 95 0.67 23 11 63.3 95 0.64 24 12 66.3 98
0.67 25 1 66.4 104 0.69 26 2 63.5 93 0.67 27 3 62.9 93 0.60 28 4
64.2 93 0.67 29 5 64.9 99 0.67 30 6 68.2 98 0.66 31 7 61.0 96 0.59
32 8 59.9 96 0.51 33 9 63.0 95 0.60 34 10 58.1 95 0.61 35 11 66.1
98 0.70 36 12 64.2 98 0.62 37 13 65.6 100 0.62 38 14 68.9 96 0.78
39 15 63.7 97 0.66 40 16 64.7 97 0.66 41 17 69.1 97 0.64 42 18 70.2
94 0.60 43 19 61.2 93 0.54 44 20 63.4 91 0.71 45 21 67.7 99 0.68 46
22 66.7 96 0.61 47 23 67.2 93 0.62 48 24 69.6 98 0.66 49 13 66.2
102 0.58 50 14 66.9 97 0.76 51 15 66.7 96 0.68 52 16 64.7 96 0.81
53 17 65.1 96 0.71 54 18 67.6 98 0.65 55 19 66.7 97 0.70 56 20 63.6
99 0.67 57 21 68.1 101 0.71 58 22 64.8 99 0.66 59 23 66.2 97 0.63
60 24 67.4 103 0.67 61 13 64.2 99 0.65 62 14 68.7 101 0.76 63 15
66.0 100 0.66 64 16 67.7 103 0.69 65 17 66.4 100 0.65 66 18 66.2 98
0.69 67 19 68.3 100 0.60 68 20 67.9 101 0.68 69 21 67.1 98 0.69 70
22 66.2 101 0.71 71 23 67.0 97 0.62 72 24 68.0 100 0.70 Average
65.5 .+-. 2.6 97 .+-. 3 0.66 .+-. 0.06
[0200] The total concentration of amikacin in the liposomal
amikacin formulation was measured during this study with the rest
of the samples using the same HPLC and amikacin standards. The
value obtained was 64 mg/mL amikacin. The % associated amikacin
post-nebulization values ranged from 58.1% to 72.7%, with an
average value of 65.5 .+-.2.6%; for 8 mL liposomal amikacin
formulation nebulized, the total recovered amount of amikacin
ranged from 426 mg to 519 mg, with an average value of 476.+-.17
mg; the calculated amount of amikacin nebulized (according to the
weight of the liposomal amikacin formulation nebulized in Table 7)
ranged from 471 mg to 501 mg, with an average value of 490.+-.8 mg;
the total amikacin recovery ranged from 91% to 104%, with an
average value of 97.+-.3% (n=72).
Liposome Size
[0201] The liposomal amikacin formulation (64 mg/mL amikacin),
either pre-nebulized or post-nebulized, was diluted appropriately
with 1.5% NaCl and the liposome particle size was measured by light
scattering using a Nicomp 380 Submicron Particle Sizer (Nicomp,
Santa Barbara, Calif.).
[0202] The liposome sizes post-nebulization of the liposomal
amikacin formulation aerosolized with twenty four nebulizer aerosol
heads with 8 mL reservoir handsets were measured. The liposome size
ranged from 248.9 nm to 288.6 nm, with an average of 264.8.+-.6.7
nm (n=72). These results are provided in Table 8. The
pre-nebulization liposome mean diameter was approximately 285 nm
(284.5 nm.+-.6.3 nm).
TABLE-US-00012 TABLE 8 Liposome size post-nebulization Aerosol Mean
Diameter Run Head # (nm) 1 1 270.9 2 2 274.6 3 3 253.9 4 4 256.3 5
5 274.0 6 6 273.6 7 7 260.0 8 8 268.1 9 9 264.7 10 10 254.8 11 11
266.9 12 12 270.0 13 1 269.6 14 2 271.2 15 3 254.6 16 4 270.7 17 5
260.8 18 6 252.3 19 7 267.8 20 8 265.0 21 9 261.5 22 10 258.0 23 11
248.9 24 12 262.4 25 1 266.0 26 2 270.4 27 3 268.6 28 4 266.6 29 5
259.4 30 6 265.2 31 7 262.4 32 8 257.7 33 9 264.1 34 10 258.5 35 11
273.4 36 12 260.2 37 13 266.0 38 14 270.2 39 15 268.2 40 16 266.2
41 17 265.5 42 18 268.5 43 19 263.3 44 20 257.8 45 21 271.3 46 22
266.2 47 23 270.6 48 24 269.7 49 13 269.1 50 14 265.7 51 15 258.7
52 16 268.0 53 17 266.2 54 18 254.0 55 19 263.9 56 20 265.3 57 21
264.5 58 22 266.5 59 23 264.8 60 24 271.7 61 13 259.8 62 14 268.8
63 15 265.9 64 16 274.7 65 17 256.2 66 18 269.7 67 19 257.7 68 20
255.7 69 21 264.8 70 22 288.6 71 23 252.1 72 24 263.4 Average 264.8
.+-. 6.7
[0203] All, documents, patents, patent applications, publications,
product descriptions, and protocols which are cited throughout this
application are incorporated herein by reference in their
entireties for all purposes.
[0204] The embodiments illustrated and discussed in this
specification are intended only to teach those skilled in the art
the best way known to the inventors to make and use the invention.
Modifications and variation of the above-described embodiments of
the invention are possible without departing from the invention, as
appreciated by those skilled in the art in light of the above
teachings. It is therefore understood that, within the scope of the
claims and their equivalents, the invention may be practiced
otherwise than as specifically described.
* * * * *