U.S. patent application number 11/570584 was filed with the patent office on 2008-09-04 for methods of treatment of endobronchial infections.
This patent application is currently assigned to NOVARTIS VACCINES AND DIAGNOSTICS, INC.. Invention is credited to Peter Challoner, John D. Lord, Carlos Rodriguez, Emil Samara, Thomas E. Tarara.
Application Number | 20080214481 11/570584 |
Document ID | / |
Family ID | 35782127 |
Filed Date | 2008-09-04 |
United States Patent
Application |
20080214481 |
Kind Code |
A1 |
Challoner; Peter ; et
al. |
September 4, 2008 |
Methods of Treatment of Endobronchial Infections
Abstract
The present invention provides methods for the treatment of an
endobronchial infection in a patient by administering to the
endobronchial system of the patient a dry powder aerosol
composition comprising from 90 to 130 mg of an aminoglycoside
antibiotic one to three times a day for a first treatment period of
20 to 36 days.
Inventors: |
Challoner; Peter;
(Emeryville, CA) ; Rodriguez; Carlos; (Emeryville,
CA) ; Samara; Emil; (Emeryville, CA) ; Tarara;
Thomas E.; (Burlingame, CA) ; Lord; John D.;
(Redwood City, CA) |
Correspondence
Address: |
CHIRON CORPORATION;INTELLECTUAL PROPERTY - R440
PO BOX 8097
EMERYVILLE
CA
94662-8097
US
|
Assignee: |
NOVARTIS VACCINES AND DIAGNOSTICS,
INC.
Emeryville
CA
NEKTAR THERAPEUTICS
San Carlos
CA
|
Family ID: |
35782127 |
Appl. No.: |
11/570584 |
Filed: |
June 20, 2005 |
PCT Filed: |
June 20, 2005 |
PCT NO: |
PCT/US05/21952 |
371 Date: |
September 4, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60580848 |
Jun 18, 2004 |
|
|
|
Current U.S.
Class: |
514/37 ; 514/35;
514/40; 514/41 |
Current CPC
Class: |
A61P 11/00 20180101;
A61P 31/04 20180101; A61P 3/00 20180101; A61K 31/70 20130101; A61P
31/00 20180101; A61P 31/02 20180101; A61K 9/0075 20130101 |
Class at
Publication: |
514/37 ; 514/35;
514/40; 514/41 |
International
Class: |
A61K 31/7036 20060101
A61K031/7036; A61P 31/04 20060101 A61P031/04 |
Claims
1. A method for the treatment of an endobronchial infection in a
patient, comprising administering to the endobronchial system of
the patient a dry powder aerosol composition comprising from 90 to
130 mg of an aminoglycoside antibiotic one to three times a day for
a first treatment period of 20 to 36 days.
2. A method of claim 1 wherein the first treatment period is
followed by a second non-treatment period wherein no aminoglycoside
antibiotic is administered to the endobronchial system of the
patient.
3. A method of claim 1 wherein the aminoglycoside antibiotic is
selected from the group consisting of gentamicin, amikacin,
kanamycin, streptomycin, neomycin, netilmicin and tobramycin, or a
pharmaceutically acceptable salt thereof.
4. A method of claim 3 wherein the aminoglycoside antibiotic is
tobramycin, or a pharmaceutically acceptable salt thereof.
5. A method of claim 4 wherein the aerosol powder composition
comprises from 100 to 120 mg of tobramycin.
6. A method of claim 5 wherein the aerosol powder composition
comprises from 110 to 115 mg of tobramycin.
7. A method of claim 1 wherein the aerosol powder composition
administered to the patient is divided into two to six unit
doses.
8. A method of claim 7 wherein the aerosol powder composition
administered to the patient is divided into three to five unit
doses.
9. A method of claim 8 wherein the aerosol powder composition is
divided into four unit doses.
10. A method of claim 2 wherein the second non-treatment period is
from 20 to 36 days.
11. A method of claim 2 wherein the first treatment period is from
26 to 30 days.
12. A method of claim 11 wherein the second non-treatment period is
from 26 to 30 days.
13. A method of claim 2 wherein the first treatment period is for
28 days.
14. A method of claim 13 wherein the second non-treatment period is
from 26 to 30 days.
15. A method of claim 2 wherein the treatment regime of the first
treatment period followed by the second non-treatment period is
repeated a multiplicity of times.
16. A method of claim 2 wherein the powder comprises particles at
least 50% of which have an aerodynamic diameter in the range of
from 1 .mu.m to 5 .mu.m.
17. A method of claim 2 wherein the patient is a cystic fibrosis
patient.
18. A method of claim 17 wherein the cystic fibrosis patient is
suffering from a Pseudomonas endobronchial infection.
19. A method of claim 1 wherein the aerosol powder is administered
to the patient using a dry powder inhaler.
20. A method of claim 1 wherein the aerosol powder is disposed
within a single container within the dry powder inhaler, and the
aerosol powder is delivered from the container into the lungs of
the human or animal subject by the inhaler.
21. A method of claim 20 wherein the aerosol powder is disposed
within multiple containers within the dry powder inhaler, and the
aerosol powder is delivered from the containers into the lungs of
the human or animal subject by the inhaler.
22. A method for the treatment of a cystic fibrosis patient
suffering from an endobronchial infection, comprising administering
to endobronchial system of the patient a dry powder aerosol
composition comprising from 110 to 115 mg of tobramycin antibiotic
twice a day for a first treatment period of 28 days, providing a
second non-treatment period of from 26 to 30 days wherein no
tobramycin antibiotic is administered to the endobronchial system
of the patient, and then repeating the first and second treatment
periods.
23. A method of claim 22 wherein the aerosol powder composition
administered to the patient is divided into three to five unit
doses.
24. A method of claim 23 wherein the aerosol powder composition is
divided into four unit doses.
25. A method of claim 22 wherein the cystic fibrosis patient is
suffering from a Pseudomonas endobronchial infection.
26. A method of claim 22 wherein the first and second treatment
periods are repeated a multiplicity of times.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/580,848, filed Jun. 18, 2004, which is
incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to new and improved methods
for treatment of susceptible endobronchial infections in patients
with dry powder formulations of aminoglycoside antibiotics, such as
tobramycin.
BACKGROUND OF THE INVENTION
[0003] Cystic fibrosis (CF) is the most common life-shortening
genetic disease in the United States and Northern Europe, affecting
approximately 30,000 individuals in the United States (Cunningham,
J. C. et al., "An Introduction to Cystic Fibrosis for Patients and
Families," 5th ed., Bethesda: Cystic Fibrosis Foundation (2003))
and a similar number of individuals in Western Europe. The genetic
defect in this autosomal recessive disease is a mutation in the CF
transmembrane conductance regulator (CFTR) gene, which codes for a
chloride-channel protein (Collins, F. S., "Cystic Fibrosis
Molecular Biology and Therapeutic Implications," Science
256:774-779 (1992)). Persons with CF typically suffer from chronic
endobronchial infections, sinusitis, and malabsorption due to
pancreatic insufficiency, increased salt loss in sweat, obstructive
hepatobiliary disease, and reduced fertility (FitzSimmons, S. C.,
"The Changing Epidemiology of Cystic Fibrosis," J Pediatr 122:1-9
(1993)). Respiratory disease is a major cause of morbidity and
accounts for 90% of mortality in persons with CF (Cystic Fibrosis
Foundation, Cystic Fibrosis Foundation Patient Registry 2003 Annual
Data Report, Bethesda, Md.: Cystic Fibrosis Foundation, (2004);
Davis, P. B. et al., "Cystic fibrosis," Amer J. Respir Crit Care
Med 154(5):1229-56 (1996)). Lung function (measured as forced
expiratory volume at 1 second (FEV.sub.1% predicted) is a
significant predictor of survival in CF. Two-year survival for a
given population of persons with CF is reduced 2-fold with each 10%
reduction in FEV.sub.1% predicted, and persons with FEV.sub.1 below
30% of predicted have a 2-year survival below 50% (Kerem, E. et
al., "Prediction of Mortality in Patients with Cystic Fibrosis," N
Engl J Med 326:1187-1191 (1992)). Rates of lung function loss vary
both between individuals and over time for a given individual.
Retrospective longitudinal analyses show rates of decline ranging
from less than 2% of FEV.sub.1% predicted per year to greater than
9% FEV.sub.1% predicted per year, with overall rate of decline
strongly associated with age of death (Corey, M. et al.,
"Longitudinal Analysis of Pulmonary Function Decline in Patients
with Cystic Fibrosis," J Pediatr 131(6):809-1 (1997)).
[0004] CF patients suffer from thickened mucus caused by perturbed
epithelial ion transport that impairs lung host defenses, resulting
in increased susceptibility to early endobronchial infections with
Staphylococcus aureus, Haemophilus influenzae, and P. aeruginosa.
By adolescence, a majority of persons with CF have P. aeruginosa
present in their sputum (Cystic Fibrosis Foundation Patient
Registry 2003 Annual Data Report (2004)). Chronic endobronchial
infections, particularly with P. aeruginosa, provoke a persistent
inflammatory response in the airway that accelerates progressive
obstructive disease characterized by diffuse bronchiectasis (Davis,
P. B. et al. (1996), supra; Winnie, G. B. et al., "Respiratory
Tract Colonization with Pseudomonas aeruginosa in Cystic Fibrosis:
Correlations Between Anti-Pseudomonas aeruginosa Antibody Levels
And Pulmonary Function," Pediatr Pulmonol 10:92-100 (1991);
Ballman, M. et al. "Long Term Follow Up of Changes in FEV.sub.1 and
Treatment Intensity During Pseudomonas Aeruginosa Colonisation in
Patients with Cystic Fibrosis," Thorax 53:732-737 (1998); Pamukcu,
A. et al., "Effects of Pseudomonas aeruginosa Colonization on Lung
Function and Anthropometric Variables in Children with Cystic
Fibrosis," Pediatr Pulmonol 19:10-15 (1995)). A link between
acquisition of chronic endobronchial P. aeruginosa infection, lung
inflammation, loss of lung function, and ultimate death is
suggested by significantly decreased survival associated with
chronic P. aeruginosa infection (Henry, R. L. et al., "Mucoid
Pseudomonas aeruginosa is a Marker of Poor Survival in Cystic
Fibrosis," Pediatr Pulmonol 12(3):158-61 (1992)), and by the
significant association of early acquisition of chronic P.
aeruginosa infection and childhood mortality (Demko, C. A. et al.,
"Gender Differences in Cystic Fibrosis: Pseudomonas aeruginosa
Infection," J Clin Epidemiol 48:1041-1049 (1995)). Chronic
Therapies that either suppress bacterial loads in the lung
(MacLusky, I. B. et al, "Long-term Effects of Inhaled Tobramycin in
Patients with Cystic Fibrosis Colonized with Pseudomonas
aeruginosa," Pediatr Pulmonol 7(1):42-8 (1989)) or suppress
resulting inflammation (Konstan, M. W. et al., "Effect of high-dose
Ibuprofen in Patients with Cystic Fibrosis," N Engl J Med
332(13):848-54 (1995)) have been shown to reduce rates of lung
function decline in infected patients.
[0005] Historically, the standard therapy for P. aeruginosa
endobronchial infections was 14 to 21 days of parenteral
antipseudomonal antibiotics, typically including an aminoglycoside.
However, parenteral aminoglycosides, as highly polar agents,
penetrate poorly into the endobronchial space. To obtain adequate
drug concentrations at the site of infection with parenteral
administration, serum levels approaching those associated with
nephro-, vestibule-, and oto-toxicity are required ("American
Academy of Otolaryngology. Guide for the evaluation of hearing
handicap," JAMA 241(19):2055-9 (1979); Brummett, R. E.,
"Drug-induced ototoxicity," Drugs 19:412-28 (1980)).
[0006] Inhalation administration of aminoglycosides offers an
attractive alternative, delivering high concentrations of
antibiotic directly to the site of infection in the endobronchial
space while minimizing systemic bioavailability (Touw, D. J. et
al., "Inhalation of Antibiotics in Cystic Fibrosis," Eur Respir J
8:1594-604 (1995); Rosenfeld, M. et al., "Aerosolized Antibiotics
for Bacterial Lower Airway Infections: Principles, Efficacy, and
Pitfalls," Clinical Pulmonary Medicine 4(2): 101-12 (1997)).
[0007] The current standard of treatment of P. aeruginosa
infections in CF patients is TOBI.RTM. tobramycin solution for
inhalation, a preservative-free, stable, and convenient formulation
of tobramycin (60 mg/mL tobramycin in 5 mL of 1/4 normal saline)
for administration via jet nebulizer, developed by PathoGenesis
Corporation, Seattle, Wash. (now Chiron Corporation, Emeryville,
Calif.). The combination of a 5 mL BID TOBI dose (300 mg
tobramycin) and the PARI LC PLUS/PulmoAide compressor delivery
system was approved by the FDA under NDA 50-753, December 1997, as
a chronic intermittent therapy for the management of P. aeruginosa
in CF patients, and remains the industry standard for this purpose.
The process of inhalation of the commercially available 300 mg TOBI
dose can take 20 minutes per dose with additional time required for
set-up and nebulizer cleaning. The aerosol administration of a 5 ml
dose of a formulation containing 300 mg of tobramycin in quarter
normal saline for the suppression of P. aeruginosa in the
endobronchial space of a patient is also disclosed in U.S. Pat. No.
5,508,269, the disclosure of which is incorporated herein in its
entirety by this reference.
[0008] Tobramycin is an aminoglycoside antibiotic produced by the
actinomycete, Streptomyces tenebrarius. Low concentrations of
tobramycin (<4 .mu.g/mL) are effective in inhibiting the growth
of many Gram-negative bacteria and under certain conditions may be
bactericidal (Neu, H. C., "Tobramycin: an overview," J Infect Dis
134: Suppl: S3-19 (1976)). Tobramycin is poorly absorbed across
mucosal surfaces, conventionally necessitating parenteral
administration. In addition, tobramycin activity is inhibited by
purulent sputum: high concentrations of divalent cations, acidic
conditions, increased ionic strength and macromolecules that bind
the drug all inhibit tobramycin in this environment. It is
estimated that 5 to 10 times higher concentrations of tobramycin
are required in the sputum to overcome these inhibitory effects
(Levy, J. et al., "Bioactivity of Gentamicin in Purulent Sputum
from Patients with Cystic Fibrosis or Bronchiectasis: Comparison
with Activity in Serum," J Infect Dis 148(6): 1069-76 (1983)).
[0009] The effectiveness of delivery of the poorly absorbed
antibiotic tobramycin to the airway by the aerosol route of cystic
fibrosis (CF) patients has been well documented. Much of this work
has been done toward treatment of chronic lung infections with P.
aeruginosa in cystic fibrosis (CF) patients. For example, a
multicenter, double blind, placebo-controlled, crossover trial of
600 mg tid of aerosolized tobramycin for endobronchial infections
due to P. aeruginosa in 71 CF patients demonstrated a significant
reduction in sputum density of this pathogen as well as improved
spirometry in the treatment group. Emergence of P. aeruginosa
strains highly resistant to tobramycin (defined as MIC .gtoreq.128
.mu.g/mL) was comparable in the placebo and treatment groups. The
presence in the sputum of Gram-negative organisms other than P.
aeruginosa intrinsically resistant to tobramycin occurred with
equal frequency during administration of tobramycin or placebo
(Ramsey, B. et al., "Response to Letter to the Editor: Aerosolized
Tobramycin in Patients with Cystic Fibrosis," N Engl J Med 329:1660
(1993)).
[0010] Although this regimen was found to be both safe and
efficacious, it is costly and inconvenient. A survey of the MICs
for P. aeruginosa isolates from initial sputum cultures for
patients at the Children's Hospital CF Center, Seattle, Wash., in
1993 found that 90% of isolates had MICs .ltoreq.16 .mu.g/mL and
98% of all isolates had MICs .ltoreq.128 .mu.g/mL. This survey
suggested that achieving a sputum tobramycin concentration of 128
.mu.g/mL should effectively treat endobronchial infections in CF
patients (Levy, J. et al., "Bioactivity of Gentamicin in Purulent
Sputum from Patients with Cystic Fibrosis or Bronchiectasis:
Comparison with Activity in Serum," J Infect Dis 148(6):1069-76
(1983)).
[0011] A randomized, crossover study compared the ability of
several nebulizers to deliver tobramycin by measuring peak sputum
tobramycin concentrations in samples collected ten minutes after
completion of the aerosol dose. This study administered TOBI.RTM.
tobramycin solution for inhalation, PathoGenesis Corporation,
Seattle, Wash. (now Chiron Corporation, Emeryville, Calif.),
containing 60 mg/mL tobramycin in 5 mL one quarter (1/4) normal
saline, using the PARI.RTM. LC jet nebulizer, PARI Respiratory
Equipment, Inc., Richmond, Va. This delivery system was shown to
deliver a mean peak sputum tobramycin concentration of 678.8
.mu.g/g (s.d. 661.0 .mu.g/g), and a median peak sputum
concentration of 433.0 .mu.g/g. Only 13% of patients had sputum
levels .ltoreq.128 .mu.g/g; 87% of patients achieved sputum levels
of .gtoreq.128 .mu.g/g (Eisenberg, J. et al., "A Comparison of Peak
Sputum Tobramycin Concentration in Patients With Cystic Fibrosis
Using Jet and Ultrasonic Nebulizer Systems. Aerosolized Tobramycin
Study Group," Chest 111(4):955-962 (1997)). Recently, the PARI.RTM.
LC jet nebulizer has been modified with the addition of one-way
flow valves, and renamed the PARI.RTM. LC PLUS. The one-way valves
in the PARI.RTM. LC PLUS have been described as permitting the
delivery of more drug than the PARI.RTM. LC jet nebulizer, while
decreasing the potential for accidental spillage and allowing for
the use of an expiratory filter. Experience has shown that mean
peak sputum tobramycin concentrations achieved using the PARI LC
PLUS jet nebulizer are significantly higher than those using the
PARI.RTM. LC jet nebulizer as described in Eisenberg et al. (1997),
supra.
[0012] In addition to the foregoing, two placebo-controlled,
multicenter, randomized, double blind clinical trials of
intermittent administration of inhaled liquid aerosol tobramycin in
cystic fibrosis patients with P. aeruginosa infection were reported
in Ramsey, B. W. et al., "Intermittent Administration of Inhaled
Tobramycin in Patients with Cystic Fibrosis. Cystic Fibrosis
Inhaled Tobramycin Study Group." N. Engl. J. Med. 340(1):23-30
(1999). In these studies, five hundred twenty subjects were
randomized to receive either 300 mg inhaled tobramycin or placebo
twice daily for 28 days followed by 28 days off study drug.
Subjects continued on treatment or placebo for three "on-off"
cycles for a total of 24 weeks. Efficacy variables included sputum
P. aeruginosa density. Tobramycin-treated patients had an average
0.8 log.sub.10 decrease in P. aeruginosa density from Week 0 to
Week 20, compared with a 0.3 log.sub.10 increase in placebo-treated
patients (P<0.001). Tobramycin-treated patients had an average
1.9 log.sub.10 decrease in P. aeruginosa density from Week 0 to
Week 4, compared with no change in placebo-treated patients
(P<0.001).
[0013] U.S. Pat. No. 6,890,907 and United States Published Patent
Application 2003/0143162 A1 disclose that patients suffering from
an endobronchial infection can be effectively treated by
administering to the patient for inhalation a dose of 4.0 ml, or
less, of a nebulized liquid aerosol formulation comprising from
about 60 to about 200 mg/ml of an aminoglycoside antibiotic, such
as tobramycin, in a physiologically acceptable carrier, in a time
period of less than about 10 minutes. The more efficient
administration of the aminoglycoside formulation permits
substantially smaller volumes of liquid aminoglycoside than the
conventional administration regime to be administered in
substantially shorter periods of time, thereby reducing the costs
of administration and drug waste. Moreover, the formulations were
shown to contain a minimal yet efficacious amount of aminoglycoside
formulated in a relatively small volume of a physiologically
acceptable solution, thereby reducing irritation of the lungs after
inhalation of the aminoglycoside formulation.
[0014] In addition to inhaled antibiotics such as the commercially
available TOBI.RTM. product, a variety of other chronic therapies
are routinely prescribed to reduce the destructive cycles of
obstruction, infection, and inflammation in the CF lung. Aggressive
Airway Clearance Therapy (Reisman, J. J. et al., "Role of
conventional physiotherapy in cystic fibrosis," J Pediatr
113(4):632-6 (1988)), inhaled bronchodilators (Konig P et al.,
"Short-term and Long-term Effects of Albuterol Aerosol Therapy in
Cystic Fibrosis: A Preliminary Report," Pediatr Pulmonol
20(4):205-14 (1995)), and mucolytics such as recombinant human
domase alpha (rhDNase; Fuchs, H. J. et al., "Effect of Aerosolized
Recombinant Human DNase on Exacerbations of Respiratory Symptoms
and on Pulmonary Function in Patients with Cystic Fibrosis. The
Pulmozyme Study Group," N Engl J Med 331(10):637-42 (1994)) are all
prescribed chronically, creating a potential for significant
treatment burden for persons with CF. It has been shown that
adherence to therapies is a significant problem for persons with CF
(Conway, S. P. et al., "Compliance with treatment in adult patients
with cystic fibrosis," Thorax 51(1):29-33 (1996)) and that lack of
compliance can vary by specific treatment (Abbott J et al.,
"Treatment Compliance in Adults with Cystic Fibrosis," Thorax
49(2):115-20 (1994)).
[0015] As described above, the commercially available TOBI.RTM.
liquid aerosol tobramycin solution for inhalation has proven to be
highly effective in treating P. aeruginosa infections in CF
patients. Given the treatment burden and adherence challenges
associated with preservation of lung function in persons with CF,
improvements in existing therapies that reduce treatment
administration time or increase convenience of treatment for
patients will facilitate patient adherence and resulting
therapeutic efficacy. Accordingly, there is a need for new and
improved methods and devices for the delivery of aminoglycoside
antibiotic compounds to a patient by inhalation to reduce
administration costs, increase patient compliance and enhance
overall effectiveness of the inhalation therapy.
SUMMARY OF THE INVENTION
[0016] The present invention provides methods for the treatment of
endobronchial infections in a patient, comprising administering to
the endobronchial system of the patient a dry powder aerosol
composition comprising from 90 to 130 mg of an aminoglycoside
antibiotic one to three times a day for a first treatment period of
20 to 36 days. In the practice of the invention, the first
treatment period may be followed by a second non-treatment period
wherein no aminoglycoside antibiotic is administered to the
endobronchial system of the patient. For the treatment of virulent
infections, the cycle of the first treatment period of
aminoglycoside treatment followed by the second non-treatment
period wherein no aminoglycoside antibiotic is administered to the
endobronchial system of the patient may be repeated two or more
times until the desired antibacterial effect is obtained. In the
case of chronic infections, such as infections occurring in cystic
fibrosis patients, the first and second treatment periods may be
repeated a multiplicity of times throughout the medical treatment
of the patient.
[0017] The methods of the invention are useful for treating any
endobronchial infection that is susceptible to an aminoglycoside
antibiotic, such as a pseudomonal endobronchial infection
associated with cystic fibrosis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing aspects and many of the attendant advantages
of this invention will become more readily appreciated as the same
become better understood by reference to the following detailed
description, when taken in conjunction with the accompanying
drawings, wherein:
[0019] FIG. 1 shows mean serum concentration of tobramycin in
subjects at various times after administration of a defined dosage
of TPI and TOBI.
[0020] FIG. 2 shows a plot of dosage of Tobramycin Powder for
Inhalation (TPI) and Tobramycin Solution for Inhalation (TOBI)
versus Area Under the Curve (AUC) (0,12).
[0021] FIG. 3 shows a plot of dosage of TPI and TOBI versus AUC
(0,.infin.).
[0022] FIG. 4 shows the average concentration of tobramycin in
sputum of subjects who had received a defined dosage of TOBI or
TPI.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Unless specifically defined herein, all terms used herein
have the same meaning as they would to one skilled in the art of
the present invention. The following abbreviations are used
herein:
[0024] Abbreviation Meaning [0025] AE adverse event [0026] ALT
alanine aminotransferase [0027] AUC area under curve [0028] BID
twice daily [0029] BUN blood urea nitrogen [0030] CaCl.sub.2
calcium chloride [0031] CF cystic fibrosis [0032] CFC
chlorofluorocarbon [0033] C.sub.max maximum concentration [0034]
CFTR cystic fibrosis transmembrane conductance regulator [0035] DPI
dry powder inhaler [0036] DSPC 1, 2
distearoyl-sn-glycero-3-phosphocholine [0037] FDA United States
Food and Drug Administration [0038] FEV.sub.1 forced expiratory
volume at 1 second [0039] FVC forced vital capacity [0040]
FEF.sub.25-75 forced expiratory flow between 25% and 75% [0041]
HPMC 2-hydroxyproplymethylcellulose [0042] IRB Institutional Review
Board [0043] IVRS Interactive Voice Response System [0044] MedDRA
Medical Dictionary for Regulatory Activities [0045] MIC minimal
inhibitory concentration [0046] P. aeruginosa Pseudomonas
aeruginosa [0047] PFOB perfluorooctyl bromide [0048] QPIT
quantitative pilocarpine iontophoresis test [0049] SAE serious
adverse event [0050] t.sub.max time to maximum concentration [0051]
TOBI.RTM. 300 mg Tobramycin Solution for Inhalation, Chiron
Corporation, Emeryville, Calif. [0052] TIP Tobramycin Inhalation
Powder
[0053] In one aspect the present invention provides methods for the
treatment of endobronchial infections in a patient, comprising
administering to the endobronchial system of the patient a dry
powder aerosol composition comprising from 90 to 130 mg of an
aminoglycoside antibiotic one to three times a day for a first
treatment period of 20 to 36 days. In the practice of the
invention, the first treatment period may be followed by a second
non-treatment period wherein no aminoglycoside antibiotic is
administered to the endobronchial system of the patient. For the
treatment of virulent infections, the cycle of the first treatment
period of aminoglycoside treatment followed by the second
non-treatment period wherein no aminoglycoside antibiotic is
administered to the endobronchial system of the patient may be
repeated two or more times until the desired antibacterial effect
is obtained. In the case of chronic infections, such as infections
occurring in cystic fibrosis patients, the first and second
treatment periods may be repeated a multiplicity of times
throughout the medical treatment of the patient.
[0054] In another aspect, the present invention provides the use of
an aminoglycoside antibiotic in the preparation of a medicament for
the treatment of endobronchial infections in a patient by
administering to the endobronchial system of the patient in a first
treatment period a dry powder aerosol composition comprising from
90 to 130 mg of an aminoglycoside antibiotic one to three times a
day for a first treatment period of 20 to 36 days. In the practice
of this aspect of the invention, the first treatment period may
similarly be followed by a second non-treatment period wherein no
aminoglycoside antibiotic is administered to the endobronchial
system of the patient, and the first and second treatment periods
may be repeated, substantially as described herein.
[0055] The methods of this aspect of the invention each include the
step of administering, by inhalation, to a human or animal subject,
in need of such administration, a therapeutically effective amount
of an aerosol powder comprising 20% by weight to 90% by weight of
an aminoglycoside antibiotic and a physiologically acceptable
carrier, wherein the powder comprises particles, and wherein at
least 50% of the particles have an aerodynamic diameter in the
range of from 1 .mu.m to 5 .mu.m.
[0056] The term "endobronchial infection" refers to a bacterial
infection located within a bronchus of the lungs. Examples of
endobronchial infections that can be treated using the methods of
the present invention include infections by gram negative
organisms, such as Pseudomonas aeruginosa, Staphylococcus aureus,
Haemophilus influenzae, Burkholderia cepacia, Stenotrophomonas
maltophilia, and Alcaligenes xiloxidants. The methods of this
aspect of the present invention can be used, for example, to treat
human beings suffering from an endobronchial infection associated
with cystic fibrosis, such as, e.g., a Pseudomonas aeruginosa
infection.
[0057] Aminoglycoside antibiotics useful in the practice of the
invention, include, for example, gentamicin, amikacin, kanamycin,
streptomycin, neomycin, netilmicin, paramecin and tobramycin. A
presently preferred aminoglycoside antibiotic for use in the
practice of the present invention is tobramycin. The aminoglycoside
antibiotic is typically administered in the form of a
pharmaceutically acceptable salt (e.g., sulfate, citrate,
ascorbate, gluconate, carbonate, tartarate, succinate, acetate, or
phosphate) or ester.
[0058] In the practice of the present invention, the aerosol powder
is inhaled by the human or animal subject, and thereby enters the
lungs of the human or animal subject. The aerosol powder comprises
particles that comprise the aminoglycoside antibiotic. It has been
found that aerosol powders (comprising an aminoglycoside
antibiotic) wherein at least 50% of the particles have an
aerodynamic diameter in the range of from 1 .mu.m to 5 .mu.m
effectively penetrate into the lungs of the human or animal
subject, thereby effectively delivering the aminoglycoside
antibiotic to the lungs of the subject. By way of example, some
aerosol powders (comprising an aminoglycoside antibiotic) useful in
the practice of the present invention comprise particles wherein at
least 60% of the particles, or at least 70% of the particles, or at
least 80% of the particles, or at least 90% of the particles, or at
least 95% of the particles, have an aerodynamic diameter in the
range of from 1 .mu.m to 5 .mu.m.
[0059] The term "aerodynamic diameter" refers to the diameter of a
unit-density sphere having the same terminal settling velocity as
the particle in question (see, e.g., "Aerosol Measurement:
Principles, Techniques and Applications". Edited by Klaus Willeke
and Paul A. Baron. Van Nostrand Reinhold, New York, 1993).
Aerodynamic diameter is used, for example, to predict where such
particles will be deposited in the respiratory tract.
[0060] "Mass median aerodynamic diameter" (abbreviated as MMAD) is
a measure of the aerodynamic size of a dispersed particle. The
aerodynamic size distribution defines the manner in which an
aerosol deposits during inhalation, and is the diameter of a unit
density sphere having the same settling velocity, generally in air,
as the particle. The aerodynamic diameter encompasses particle
shape, density and physical size of a particle. When there is a
log-normal distribution, the aerodynamic size distribution may be
characterized by the mass median aerodynamic diameter (MMAD). As
used herein, MMAD refers to the midpoint or median of the
aerodynamic particle size distribution of an aerosolized powder
determined by Anderson cascade impaction.
[0061] In brief, cascade impaction devices include a series of
screens of decreasing pore size. The screens trap particles within
a moving jet that passes through the impactor. The amount of
particulate material (having particle sizes within a defined size
range) that is trapped on each screen can be determined by washing
the screen and measuring the amount of eluted material. Examples of
cascade impactors, and their use, are described in Chapter 601
(Aerosols) of the Pharmacopoeia of the United States (26th
Revision), the cited portion of which publication is incorporated
herein by reference.
[0062] The powdered aminoglycoside antibiotic formulations useful
in the practice of the present invention typically contain less
than 15% by weight moisture, usually below about 11% by weight, and
preferably below about 8% by weight.
[0063] In the practice of the present invention a therapeutically
effective amount of an aerosol powder comprising an aminoglycoside
antibiotic is administered by inhalation to a patient suffering
from an endobronchial infection. A therapeutically effective amount
of an aerosol powder contains sufficient aminoglycoside antibiotic
to completely or partially inhibit the growth of susceptible
bacteria in the lungs of the patient. As a representative example,
for the aminoglycoside tobramycin therapeutically effective amounts
are obtained by administering to a patient from once daily to three
times a day, and in preferred aspects of the invention twice a day,
an aerosol powder compositions comprising a dosage from about 90 mg
to about 130 mg, more preferably from about 100 mg to about 120 mg,
and most preferably from about 110 mg to about 115 mg of tobramycin
(determined as free-base weight excluding the weight of
counterion(s) that may be present).
[0064] The dosage of administered aminoglycoside, such as
tobramycin, may be administered from a single container as a single
unit dose, or it may be divided into multiple containers or units
doses for sequential administration, depending of the inhalation
device used for delivery of the antibiotic. For example, the
administered dosage of aminoglycoside antibiotic may be divided
into two to six unit doses, more preferably three to five unit
doses and even more preferably four unit doses. In one
representative embodiment a dosage for administration of 112 mg of
tobramycin (determined as free-base weight excluding the weight of
counterion(s) that may be present) is loaded into 4 separate #2
HPMC capsules at fill weights of 27 mg of tobramycin as free base
per capsule.
[0065] The dry powder aerosol compositions of the invention are
administered to a patient for a first treatment period of from 20
to 36 days, more preferably from 26 to 30 days, and even more
preferably for about 28 days. This first treatment period is
followed by a second non-treatment period wherein no aminoglycoside
antibiotic is administered to the endobronchial system of the
patient. In one aspect of the invention, the second non-treatment
period will continue for about 20 to 36 days, more preferably from
about 26 to about 30 days, and most preferably for about 28
days.
[0066] In one representative embodiment, the methods of the
invention are used to treat cystic fibrosis patients for management
of chronic Pseudomonas aeruginosa infections. In this aspect, the
invention contemplates the treatment of a cystic fibrosis patient
suffering from an endobronchial infection, comprising administering
to endobronchial system of the patient a dry powder aerosol
composition comprising from 110 to 115 mg of tobramycin antibiotic
twice a day for a first treatment period of 28 days, providing a
second non-treatment period of from 26 to 30 days wherein no
tobramycin antibiotic is administered to the endobronchial system
of the patient, and then repeating the first and second treatment
periods. In this aspect of the invention, the 110 to 115 mg dosage
of tobramycin may be divided into three to five unit doses,
preferably into four unit doses, for sequential administration.
Since cystic fibrosis patients tend to be chronically infected with
P. aeruginosa, the cycle of treatment for the first treatment
period followed by the second non-treatment period will typically
be repeated a plurality or multiplicity of times, and may be
continued indefinitely for long term management of endobronchial
infections in the cystic fibrosis patient.
[0067] The aerosol powder typically comprises from 20% (by weight)
to 90% (by weight) of aminoglycoside antibiotic. Thus, in some
embodiments of the present invention the aerosol powder comprises
from 30% (by weight) to 80% (by weight) of an aminoglycoside
antibiotic. In some embodiments of the present invention the
aerosol powder comprises from 40% (by weight) to 70% (by weight) of
an aminoglycoside antibiotic. In this context, the percentage (by
weight) of the aminoglycoside antibiotic refers to the amount of
the free antibiotic, excluding the weight of counterion(s) that may
be present.
[0068] Aerosol powders of the invention typically, but not
necessarily, include at least one physiologically acceptable
carrier. For example, the aerosol powder can include one or more
excipients, and/or any other component that improves the
effectiveness of the aminoglycoside antibiotic. Such excipients may
serve simply as bulking agents when it is desired to reduce the
active agent concentration in the powder which is being delivered
to a patient. Such excipients may also serve to improve the
dispersability of the powder within a powder dispersion device in
order to provide more efficient and reproducible delivery of the
active agent and to improve the handling characteristics of the
active agent (e.g., flowability and consistency) to facilitate
manufacturing and powder filling. In particular, the excipient
materials can often function to improve the physical and chemical
stability of the aminoglycoside, to minimize the residual moisture
content and hinder moisture uptake, and to enhance particle size,
degree of aggregation, surface properties (e.g., rugosity), ease of
inhalation, and targeting of the resultant particles to the deep
lung.
[0069] Pharmaceutical excipients and additives useful in the
aminoglycoside compositions useful in the practice of the present
invention include, but are not limited to, proteins, peptides,
amino acids, lipids, polymers, and carbohydrates (e.g., sugars,
including monosaccharides, di-, tri-, tetra-, and oligosaccharides;
derivatized sugars such as alditols, aldonic acids, esterified
sugars; and polysaccharides or sugar polymers), which may be
present singly or in combination. Exemplary protein excipients
include serum albumin such as human serum albumin (HSA),
recombinant human albumin (rHA), gelatin, and casein.
Representative amino acid/polypeptide components, which may also
function in a buffering capacity, include alanine, glycine,
arginine, betaine, histidine, glutamic acid, aspartic acid,
cysteine, lysine, leucine, proline, isoleucine, valine, methionine,
phenylalanine, and aspartame, although arginine is less preferred.
Polyamino acids of the representative amino acids such as
di-leucine and tri-leucine are also suitable for use with the
present invention.
[0070] Carbohydrate excipients suitable for use in the invention
include, for example, monosaccharides such as fructose, maltose,
galactose, glucose, D-mannose, and sorbose; disaccharides, such as
lactose, sucrose, trehalose, cellobiose; polysaccharides, such as
raffinose, melezitose, maltodextrins, dextrans, and starches; and
alditols, such as mannitol, xylitol, maltitol, lactitol, xylitol
sorbitol (glucitol), and myoinositol.
[0071] The aminoglycoside compositions may also include a buffer or
a pH adjusting agent; typically, the buffer is a salt prepared from
an organic acid or base. Representative buffers include organic
acid salts such as salts of citric acid, ascorbic acid, gluconic
acid, carbonic acid, tartaric acid, succinic acid, acetic acid, or
phthalic acid; Tris, tromethamine hydrochloride, or phosphate
buffers.
[0072] Additionally, the aminoglycoside compositions useful in the
practice of the invention may include polymeric
excipients/additives such as polyvinylpyrrolidones, hydroxypropyl
methylcellulose, methylcellulose, ethylcellulose, Ficolls (a
polymeric sugar), dextran, dextrates (e.g., cyclodextrins, such as
2-hydroxypropyl-.beta.-cyclodextrin, hydroxyethyl starch),
polyethylene glycols, pectin, salts (e.g., sodium chloride),
antioxidants, antistatic agents, surfactants (e.g., polysorbates
such as "TWEEN 20" and "TWEEN 80", lecithin, oleic acid,
benzalkonium chloride, and sorbitan esters), lipids (e.g.,
phospholipids, fatty acids), steroids (e.g., cholesterol), and
chelating agents (e.g., EDTA). Other examples of pharmaceutical
excipients and/or additives suitable for use in the aminoglycoside
compositions are listed in "Remington: The Science & Practice
of Pharmacy", 19th ed., Williams & Williams, (1995), and in the
"Physician's Desk Reference", 52nd ed., Medical Economics,
Montvale, N.J. (1998), the disclosures of which are herein
incorporated by reference.
[0073] A presently preferred combination of excipients is lecithin
and calcium chloride. Lecithin is a member of the
phosphatidylcholine group of naturally-occurring phospholipids that
act as surfactants in mammalian (including human) lungs.
[0074] The aminoglycoside compositions useful in the practice of
the invention may include a dispersing agent for improving the
intrinsic dispersability properties of the aminoglycoside powders.
Suitable agents are disclosed in PCT applications WO 95/31479, WO
96/32096, and WO 96/32149, hereby incorporated in their entirety by
reference. As described therein, suitable agents include water
soluble polypeptides and hydrophobic amino acids such as
tryptophan, leucine, phenylalanine, and glycine. Leucine and
tri-leucine are particularly preferred for use according to this
invention.
[0075] The solid state matrix formed by the aminoglycoside and
excipient imparts a stabilizing environment to the aminoglycoside.
The stabilizing matrix may be crystalline, an amorphous glass, or a
mixture of both forms. Most suitable are dry powder formulations
which are a mixture of both forms. For aminoglycoside dry powder
formulations which are substantially amorphous, preferred are those
formulations exhibiting glass transition temperatures (T.sub.g)
above about 35.degree. C., preferably above about 45.degree. C.,
and more preferably above about 55.degree. C. Preferably, T.sub.g
is at least 20.degree. C. above the storage temperature. According
to a preferred embodiment, the aminoglycoside compositions comprise
a phospholipid as the solid state matrix as disclosed in WO
99/16419 and WO 01/85136, hereby incorporated in their entirety by
reference.
[0076] Dry powder aminoglycoside compositions may be prepared by
spray drying under conditions which result in a substantially
amorphous glassy or a substantially crystalline bioactive powder as
described above. Spray drying of the aminoglycoside-solution
formulations is carried out, for example, as described generally in
the "Spray Drying Handbook," 5th ed., K. Masters, John Wiley &
Sons, Inc., NY, N.Y. (1991), and in WO 97/41833, the contents of
which are incorporated herein by reference.
[0077] To prepare an aminoglycoside solution for spray-drying
according to one embodiment of the invention, an aminoglycoside is
generally dissolved in a physiologically acceptable solvent such as
water. The pH range of solutions to be spray-dried is generally
maintained between about 3 and 10, preferably 5 to 8, with near
neutral pHs being preferred, since such pHs may aid in maintaining
the physiological compatibility of the powder after dissolution of
powder within the lung. The aqueous formulation may optionally
contain additional water-miscible solvents, such as alcohols,
acetone, and the like. Representative alcohols are lower alcohols
such as methanol, ethanol, propanol, isopropanol, and the like.
Aminoglycoside solutions will generally contain aminoglycoside
dissolved at a concentration from 0.05% (weight/volume) to about
20% (weight/volume), usually from 0.4% to 5.0% (weight/volume).
[0078] The aminoglycoside-containing solutions are then spray dried
in a conventional spray drier, such as those available from
commercial suppliers such as Niro A/S (Denmark), Buchi
(Switzerland), and the like, resulting in a stable, aminoglycoside
dry powder. Optimal conditions for spray drying the aminoglycoside
solutions will vary depending upon the formulation components, and
are generally determined experimentally. The gas used to spray dry
the material is typically air, although inert gases such as
nitrogen or argon are also suitable. Moreover, the temperature of
both the inlet and outlet of the gas used to dry the sprayed
material is such that it does not cause deactivation of
aminoglycoside in the sprayed material. Such temperatures are
typically determined experimentally, although generally, the inlet
temperature will range from about 50.degree. C. to about
200.degree. C. while the outlet temperature will range from about
30.degree. C. to about 150.degree. C.
[0079] Aminoglycoside dry powders may also be prepared by
lyophilization, vacuum drying, spray freeze drying, super critical
fluid processing, or other forms of evaporative drying or by
blending, grinding, or jet milling formulation components in dry
powder form. In some instances, it may be desirable to provide the
aminoglycoside dry powder formulation in a form that possesses
improved handling/processing characteristics, e.g., reduced static,
better flowability, low caking, and the like, by preparing
compositions composed of fine particle aggregates, that is,
aggregates or agglomerates of the above-described aminoglycoside
dry powder particles, where the aggregates are readily broken back
down to the fine powder components for pulmonary delivery, as
described, e.g., in U.S. Pat. No. 5,654,007, incorporated herein by
reference. Alternatively, the aminoglycoside powders may be
prepared by agglomerating the powder components, sieving the
materials to obtain the agglomerates, spheronizing to provide a
more spherical agglomerate, and sizing to obtain a uniformly-sized
product, as described, e.g., in WO 95/09616, incorporated herein by
reference. The aminoglycoside dry powders are preferably maintained
under dry (i.e., relatively low humidity) conditions during
manufacture, processing, and storage.
[0080] According to one embodiment, an exemplary powdered
tobramycin formulation useful in the practice of the present
invention may be made according to the emulsification/spray drying
process disclosed in WO 99/16419 and WO 01/85136 cited above.
Formulations according to such embodiments are engineered to
comprise dry powder particles comprising at least 75% w/w
tobramycin, preferably at least 85% w/w tobramycin, 2-25% w/w of a
phospholipid, preferably 8-18% w/w, and 0-5% w/w of a metal ion
such as calcium chloride. The particles of this embodiment
generally have an MMAD of from 1 micron to 5 microns, and a bulk
density of greater than 0.08 g/cm.sup.3, preferably greater than
0.12 g/cm.sup.3.
[0081] Another exemplary powdered tobramycin formulation useful in
the practice of the present invention may be produced by creating
an emulsion containing active tobramycin,
1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), CaCl.sub.2 and
perfluorooctyl bromide (PFOB). This feedstock emulsion is then
sprayed through an atomizer nozzle, producing fine droplets. As the
droplets dry, water and PFOB evaporate yielding phospholipid-based
spherical particles with porous structure. These spheres are of low
density and thus demonstrate favorable aerodynamic characteristics
(e.g., the spherical particles have an aerodynamic diameter in the
range of from 1 .mu.m to 5 .mu.m). Their high surface porosity also
reduces particle-to-particle contact, decreasing the energy
required for aerosol suspension.
[0082] The aerosol powder (comprising an aminoglycoside antibiotic)
can be administered using a dry powder inhaler that uses a
patient's (e.g., human's or animal's) inhaled breath to deliver the
powdered aminoglycoside antibiotic formulation to the lungs. An
example of a useful dry powder inhaler is the model T-326 inhaler
(Nektar Therapeutics, 150 Industrial Road, San Carlos, CA 94070,
U.S.A.). Other examples of useful dry powder inhalation devices are
described in U.S. Pat. Nos. 5,458,135; 5,740,794; 5,775,320; and
5,785,049, each of which patents are incorporated herein by
reference. When administered using a device of this type, the
powdered medicament is contained in a receptacle having a
puncturable lid or other access surface, preferably a blister
package or cartridge, where the receptacle may contain a single
dosage unit or multiple dosage units. Exemplary methods for filling
large numbers of cavities with metered doses of dry powder
medicament are described in U.S. Pat. No. 5,826,633, incorporated
herein by reference.
[0083] Also suitable for delivering the aminoglycoside powders
described herein are dry powder inhalers of the type described, for
example, in U.S. Pat. Nos. 3,906,950, 4,013,075, 4,069,819, and
4,995,385, each of which patents are incorporated herein by
reference, wherein a premeasured dose of aminoglycoside dry powder
for delivery to a subject is contained within a capsule, such as a
hard gelatin capsule. The size of the capsule, such as 00, 0, No.
1, or No. 3 sized capsules, depends, among other factors, upon the
inhalation device used to administer the powders.
[0084] Other dry powder dispersion devices for pulmonarily
administering aminoglycoside dry powders include those described,
for example, in EP 129985, EP 472598, EP 467172, and U.S. Pat. No.
5,522,385, each of which patents are incorporated herein in their
entirety by reference. Also suitable for delivering the
aminoglycoside dry powders of the invention are inhalation devices
such as the Astra-Draco "TURBUHALER". This type of device is
described in detail in U.S. Pat. Nos. 4,668,218, 4,667,668, and
4,805,811, all of which are incorporated herein by reference.
[0085] Also suitable are devices which employ the use of a piston
to provide air for either entraining powdered medicament, lifting
medicament from a carrier screen by passing air through the screen,
or mixing air with powder medicament in a mixing chamber with
subsequent introduction of the powder to the patient through the
mouthpiece of the device, such as described in U.S. Pat. No.
5,388,572, incorporated herein by reference.
[0086] In view of the foregoing, it will be understood that a
therapeutically effective amount of an aerosol powder (comprising
an aminoglycoside antibiotic) can be administered from a single
container, or from more than one container, disposed within a dry
powder inhalation device. For example, a dry powder inhalation
device may be loaded with a single container containing a
therapeutically effective amount of an aerosol powder (comprising
an aminoglycoside antibiotic), and the contents of the container
are inhaled by a human or animal subject. Again by way of example,
a dry powder inhaler may be loaded with multiple unit dose
containers (e.g., 2, 3, or 4 containers), such as #2 HPMC capsules,
that separately contain less than a therapeutically effective
amount of an aerosol powder (comprising an aminoglycoside
antibiotic), but which together contain a therapeutically effective
amount of the aerosol powder. The dry powder inhaler discharges the
contents of all of the containers disposed therein, and thereby
provides the user with a therapeutically effective amount of the
aerosol powder.
[0087] The aminoglycoside treatment regimen of the present
invention may be used alone or in combination with one or more
additional agents for the treatment of endobronchial infections,
particularly infections by P. aeruginosa. In this aspect of the
invention, the one or more additional agents for the treatment of
endobronchial infections may be administered during the first
treatment period of aminoglycoside treatment, during the second
non-treatment period wherein no aminoglycoside antibiotic is
administered to the endobronchial system of the patient, or during
both the first and second treatment periods. In one embodiment of
this aspect of the invention, the one or more additional agents for
the treatment of endobronchial infections is administered during
the second non-treatment period wherein no aminoglycoside
antibiotic is administered to the endobronchial system of the
patient. Suitable additional agents for the treatment of
endobronchial infections include, for example, non-aminoglycoside
antiinfective agents, such as monobactam, .beta.-lactam, macrolide,
fluoroquinolone and/or glycopeptide antibiotic compounds. For
example, the non-aminoglycoside antiinfective agent may be
aztreonam.
[0088] The emitted dose (ED) of the powdered aminoglycoside
antibiotic formulations will generally be greater than 50%. More
preferably, the ED of the powdered aminoglycoside antibiotic
formulations useful in the practice of the present invention is
greater than 70%, and is often greater than 80%. As used herein,
the term "emitted dose" or "ED" refers to an indication of the
delivery of dry powder from a suitable inhaler device after a
firing or dispersion event from a powder unit, capsule, or
reservoir. ED is defined as the ratio of the dose delivered by an
inhaler device to the nominal dose (i.e., the mass of powder per
unit dose placed into a suitable inhaler device prior to firing).
The ED is an experimentally-determined amount, and is typically
determined using an in-vitro device set up which mimics patient
dosing. To determine an ED value, a nominal dose of dry powder (as
defined above) is placed into a suitable dry powder inhaler, which
is then actuated, dispersing the powder. The resulting aerosol
cloud is then drawn by vacuum from the device, where it is captured
on a tared filter attached to the device mouthpiece. The amount of
powder that reaches the filter constitutes the delivered dose. For
example, for a 50 mg, dry powder-containing #2 capsule placed into
an inhalation device, if dispersion of the powder results in the
recovery of 40 mg of powder on a tared filter as described above,
then the ED for the dry powder composition is: 40 mg (delivered
dose)/50 mg (nominal dose).times.100=80%.
[0089] In yet other aspects, the invention provides for kits for
use in the treatment of endobronchial infections in a patient, the
kits comprising one or more doses of from 90 to 130 mg of a dry
powder aminoglycoside antibiotic together with instructions for
administration of a dosage to the endobronchial system of the
patient using a dry powder inhalation device one to three times a
day for a first treatment period of 20 to 36 days. In this aspect
of the invention, the instructions may further provide that the
first treatment period may be followed by a second non-treatment
period wherein no aminoglycoside antibiotic is administered to the
endobronchial system of the patient, and that the cycle of the
first treatment period of aminoglycoside treatment followed by the
second non-treatment period wherein no aminoglycoside antibiotic is
administered to the endobronchial system of the patient may be
repeated two or more times until the desired antibacterial effect
is obtained, substantially as described herein. In the kits of the
invention, the one or more doses may be contained in a single
container as a single unit dose, or it may be divided into multiple
containers or units doses for sequential administration, depending
of the inhalation device used for delivery of the antibiotic. For
example, the administered dosage of aminoglycoside antibiotic may
be divided into two to six unit doses, more preferably three to
five unit doses and even more preferably four unit doses. In one
representative embodiment the kits of the invention contain dosages
for administration of 112 mg of tobramycin (determined as free-base
weight excluding the weight of counterion(s) that may be present)
loaded into 4 separate #2 HPMC capsules at fill weights of 27 mg of
tobramycin as free base per capsule.
[0090] The following examples merely illustrate the best mode now
contemplated for practicing the invention, but should not be
construed to limit the invention.
Example 1
Preparation of Tobramycin Powder for Inhalation (TPI)
[0091] A tobramycin sulfate dry powder composition is prepared
according to the following procedure. Sterile Water for Irrigation
(SWFI) is heated above the gel to liquid crystal temperature (about
80.degree. C.) of disteroyl phosphatidylcholine (DSPC). DSPC and
calcium chloride dihydrate are then added to the heated water. The
resulting lipid dispersion is mixed in an UltraTurrax T-50 (IKA
Labortechnik) at 8,000 rpm for 5 min. Perfluorooctyl bromide (PFOB)
is then added dropwise (15 ml/min) to the lipid dispersion under
mixing. After the addition is complete the resulting PFOB-in-water
emulsion is mixed for an additional 10 min at 10,000 rpm.
Emulsification in the UltraTurrax produces droplets in the
micron-size range. Tobramycin sulfate is then dissolved in the
continuous phase of the emulsion and the resulting dispersion is
used as the feedstock for spray drying. The feedstock is then spray
dried to obtain a dry powder formulation having the composition set
forth in Table 1 below.
TABLE-US-00001 TABLE 1 TPI Formulation. Component Amount Tobramycin
63.1% w/w Sulfate 21.9% w/w DSPC 14.02% w/w CaCl.sub.2 0.98 w/w
[0092] The powder is placed into a capsule filling station at a
relative humidity of 10 to 15% and allowed to equilibrate for 10
minutes, and then filled into #2 HPMC capsules at a fill weight of
50 mg (27 mg of tobramycin as free base) per capsule.
Example 2
[0093] This Example describes a clinical study that demonstrates
that single dose administration of a tobramycin dry powder
composition of the invention results in a more efficient delivery
of tobramycin than administration of a tobramycin solution, while
maintaining similar tobramycin pharmacokinetics.
[0094] Overall Study Design and Plan
[0095] The study was designed as a randomized, open-label,
sequential-cohort, active-controlled, single-dose, dose-escalation
study. In each sequential cohort, subjects were randomized in a 3:1
ratio to receive either a single dose of Tobramycin Powder for
Inhalation (TPI) administered using a T-326 Inhaler (Nektar
Therapeutics, San Carlos, CA, USA), according to the dosing
schedule shown below, or a single dose of 300 mg Tobramycin
Solution for Inhalation (TOBI), aerosolized by a PARI LC PLUS.TM.
jet nebulizer with a DeVilbiss PulmoAide.TM. compressor. Subjects
were allowed to participate in one cohort only.
[0096] Escalation to the next TPI treatment cohort proceeded after
review by a Data Monitoring Committee (DMC) of all
treatment-emergent adverse events (AEs) and other safety results of
the completed cohort and if neither of the following criteria were
met: Three or more subjects within a cohort treated with TPI
experience at least a 20% relative decline in FEV.sub.1 within 30
minutes after the end of dosing; any TPI-dosed subject experienced
a study drug-related Serious Adverse Event (SAE).
[0097] Experimental Treatment
[0098] A single dose of TPI was administered using the T-326
Inhaler: [0099] Cohort 1: Two capsules of TPI (14 mg dosage
strength of tobramycin as free base per capsule ("dosage
strength")) [0100] Cohort 2: Four capsules of TPI (14 mg dosage
strength) [0101] Cohort 3: Two capsules of TPI (28 mg dosage
strength) [0102] Cohort 4: Four capsules of TPI (28 mg dosage
strength) [0103] Cohort 5: Three capsules of TPI (28 mg dosage
strength)
[0104] Control Treatment
[0105] A single dose of TOBI at 300 mg/5 mL [preservative free
tobramycin 60 mg/mL (excipient 5 mL of 1/4 normal saline adjusted
to a pH of 6.0.+-.0.5)] aerosolized by a PARI LC PLUS jet nebulizer
with a DeVilbiss PulmoAide compressor.
[0106] Up to 80 subjects of at least 6 years of age with a
confirmed diagnosis of cystic fibrosis (CF) were randomized and
treated in the study. Each cohort randomized 12 subjects to the TPI
arm and 4 subjects to the TOBI arm for a total of 16 subjects per
cohort.
[0107] Subjects were screened for eligibility 7 to 9 days prior to
study drug administration. Subjects were evaluated for safety and
for sputum and serum tobramycin concentrations at predose, at 30
minutes, and at 1, 2, 4, 8, and 12 hours after the single dose of
study drug was administered under supervision. A 7-day (.+-.2 days)
follow-up visit was conducted.
[0108] Discussion of Study Design, Including Choice of Control
Group
[0109] The primary outcome measure for this study was the general
safety and tolerability of the experimental treatment. To better
assess this outcome, a 3:1 randomization scheme was chosen to
maximize enrollment into the experimental treatment arm.
[0110] The active concurrent control for this study was 300 mg/5 mL
TOBI delivered by a PARI LC PLUS jet nebulizer driven by a
DeVilbiss PulmoAide compressor. TOBI is indicated for the
management of cystic fibrosis patients with P. aeruginosa.
[0111] Inclusion Criteria for Selection of Study Population
[0112] Subjects were eligible to participate in the study if they
met all of the following inclusion criteria. [0113] Provide written
informed consent and HIPAA authorization prior to the performance
of any study-related procedure. [0114] Male and female subjects
.gtoreq.6 years of age at the time of screening. [0115] Diagnosis
of cystic fibrosis (CF) with documented sweat chloride .gtoreq.60
meq/L by quantitative pilocarpine iontophoresis test (QPIT) and/or
genotype with two identifiable mutations consistent with CF,
accompanied by one or more clinical features consistent with CF.
[0116] For female subjects who are .gtoreq.11 years of age or who
have reached menarche: A negative serum pregnancy test. Sexually
active females of childbearing age must agree to use contraception
during the study period. [0117] Able to expectorate sputum samples
on command. [0118] FEV.sub.1.gtoreq.40% of predicted value
(calculated using Knudson equations based on gender, age, and
height). [0119] Able to comply with all protocol requirements.
[0120] Clinically stable in the opinion of the investigator.
[0121] Exclusion Criteria for Selection of Study Subjects
[0122] Subjects were excluded from participating in the study if
they met any of the following exclusion criteria. [0123]
Administration of inhaled or intravenous aminoglycosides within 14
days prior to study drug administration and throughout the study
period. [0124] Administration of any investigational treatment
within 14 days prior to study drug administration and throughout
the study period. [0125] Administration of loop diuretics within 7
days prior to study drug administration and throughout the study
period. [0126] Hemoptysis more than 60 cc at any time within 30
days prior to study drug administration. [0127] Known local or
systemic hypersensitivity to aminoglycosides or inhaled
antibiotics. [0128] Serum creatinine 2 mg/dl or more, BUN 40 mg/dl
or more, or an abnormal urine analysis defined as 2+ or greater
proteinuria.
[0129] Removal of Subjects from Therapy or Assessment
[0130] Subjects or their parents or legal guardians could withdraw
their consent to participate in the study at any time without
prejudice. The investigator could withdraw a subject if, in his or
her clinical judgment, it was in the best interest of the subject
or if the subject could not comply with the protocol. Whenever
possible, the tests and evaluations listed for the termination
visit were carried out.
[0131] If a subject failed to return for the necessary visits, an
effort was to be made to determine the reason(s). This information
was to be recorded on the appropriate case report form (CRF).
[0132] Randomized subjects who withdrew from the study without
being dosed were replaced. Any randomized subject who withdrew
after dosing was not replaced. The reason for withdrawal and the
date of withdrawal were to be recorded on the CRF. The reasons for
withdrawal were classified as follows: [0133] Adverse event; [0134]
Protocol violation; [0135] Lost to follow-up; [0136] Withdrawal of
consent; [0137] Death; [0138] Inappropriate enrollment; [0139]
Administrative reason; [0140] Other, not specified above.
[0141] Treatments Administered
[0142] Up to 80 subjects were randomized and treated. Each subject
received a single dose of either the control treatment or the
experimental treatment as listed below.
[0143] Experimental Treatment: Administered Using the T-326
Inhaler
[0144] Cohort 1: Two capsules of TPI (14 mg dosage strength)
[0145] Cohort 2: Four capsules of TPI (14 mg dosage strength)
[0146] Cohort 3: Two capsules of TPI (28 mg dosage strength)
[0147] Cohort 4: Four capsules of TPI (28 mg dosage strength)
[0148] Cohort 5: Three capsules of TPI (28 mg dosage strength)
[0149] Control Treatment
[0150] TOBI at 300 mg/5 mL [preservative free tobramycin 60 mg/mL
(excipient 5 mL of 1/4 normal saline adjusted to a pH of
6.0.+-.0.5)] aerosolized by a PARI LC PLUS jet nebulizer with a
DeVilbiss PulmoAide compressor.
[0151] Investigational Product Characteristics
[0152] TPI used in this study is a dry powder formulation of
tobramycin and two excipients: 1,2
distearoyl-sn-glycero-3-phosphocholine (DSPC) and calcium chloride
(CaCl.sub.2). TPI was filled into individual size
2-hydroxypropylmethylcellulose (HPMC) capsules containing either 25
mg or 50 mg of powder. Two dosage strengths of tobramycin powder
were used in the present study: 14 mg tobramycin per capsule and 28
mg tobramycin per capsule.
[0153] TOBI.RTM. Tobramycin Solution for Inhalation (300 mg/5 mL)
is a sterile, non-pyrogenic, preservative-free antibiotic prepared
for aerosolization. Each mL of study drug contains 60 mg tobramycin
and 2.25 mg sodium chloride in sterile water for injection, pH
6.0.+-.0.5.
[0154] Directions for Administration
[0155] Subjects randomized to the control treatment received 300 mg
of TOBI.RTM. Tobramycin Solution for Inhalation at 60 mg/mL.
TOBI.RTM. Tobramycin Solution for Inhalation was administered to
subjects via a PARI LC PLUS jet nebulizer and DeVilbiss PulmoAide
Compressor. The 300 mg dose of TOBI.RTM. Tobramycin Solution for
Inhalation was supplied as a commercial ampoule of TOBI.RTM.
Tobramycin Solution for Inhalation. Two 5 mL ampoules of study drug
were provided in a foil pouch. Although this was a single-dose
study, a foil pouch containing two 5-mL ampoules of study drug was
provided to subjects in the event that there was accidental
spillage of the study medication during preparation and set-up of
the nebulizer and delivery system.
[0156] Subjects randomized to the experimental treatment received a
single dose of TPI consisting of two or four capsules of 14 mg
dosage strength or two, three, or four capsules of 28 mg dosage
strength. TPI was administered to subjects via a T-326 Inhaler. TPI
capsules were sealed in a double foil-wrapped, moisture-proof
container and were to be administered within 30 minutes of opening
the container. For cohorts 1, 2, and 3, only one T-326 Inhaler
device was to be used to complete the single dose administration.
For cohorts 4 and 5, the T-326 Inhaler device was to be replaced
after the second capsule was administered; therefore, two T-326
Inhalers were to be used to complete the single dose administration
for these cohorts.
[0157] Detailed instructions on the preparation and use of both the
control and experimental treatment were provided to research staff
at the study sites.
[0158] Method of Assigning Subjects to Treatment Groups
[0159] Eligible subjects were randomly assigned in a 3:1 ratio to
either the experimental or control treatment group. Once the
investigator or research coordinator confirmed that the subject met
eligibility criteria, staff completed a randomization worksheet for
the subject and received a subject number and treatment assignment
via an Interactive Voice Response System (IVRS).
[0160] At the outset of the study, up to 80 subjects in five
cohorts were expected to be randomized, 60 to the experimental
treatment (12 subjects in each cohort) and 20 to the control
treatment (4 subjects in each cohort).
[0161] Selection of Doses Used in the Study
[0162] The dose for the control treatment was the FDA-approved dose
of 300 mg TOBI for the management of P. aeruginosa in CF patients 6
years of age and older. Using PK modeling, the systemic
bioavailability of the 300 mg dose of TOBI delivered via the PARI
LC PLUS jet nebulizer/DeVilbiss PulmoAide compressor was estimated
to be 11.7% of the nebulized dose. The mean and standard deviation
of the serum concentration of the 300 mg TOBI dose, one hour after
inhalation, was 1.0.+-.0.58 .mu.g/mL, suggesting a wide range of
deposition.
[0163] The dose for the experimental treatment was two or four TPI
capsules containing 14 mg tobramycin/capsule; or two, three, or
four TPI capsules containing 28 mg tobramycin/capsule.
[0164] Selection and Timing of Dose for Each Subject
[0165] Subjects were given a single dose of either 300 mg TOBI.RTM.
Tobramycin Solution for Inhalation at 60 mg/mL or a single dose of
TPI consisting of two or four capsules of 14 mg dosage strength, or
two, three, or four capsules of 28 mg dosage strength. There was no
restriction on the timing of dosing in relation to meals.
[0166] Blinding
[0167] The study was an open-label clinical investigation. The use
of two different delivery systems makes blinding of the treatment
identity impractical.
[0168] Prior and Concomitant Therapy
[0169] Additional supportive therapy was administered in accordance
with standard practice at each study site. Medications listed in
the exclusion criteria were not administered to the subject from
the time of screening through the follow-up visit.
[0170] Subjects were allowed to use bronchodilators before taking
the study drug. Bronchodilators were administered only to subjects
who routinely used bronchodilators for clinical therapy. Routine
use is defined as once or more daily for two weeks prior to
screening. Subjects on short-acting bronchodilators were
administered the medication 15 to 60 minutes prior to the
initiation of the study drug. Subjects on long-acting
bronchodilators took the medication as prescribed in the preceding
24 hours.
[0171] The use of the following drugs was prohibited: any form of
aminoglycosides or any investigational treatment within 14 days
prior to study drug administration and throughout the study period;
loop diuretics within seven days prior to study drug administration
and throughout the study period.
[0172] Treatment Compliance
[0173] The subject self-administered the single dose of study drug
in the presence of the investigator or research coordinator.
Reasons for any premature termination, interruption, or delay in
study drug administration were recorded on the source documentation
and CRF. Total study drug administration time was recorded on the
source documentation and CRF.
[0174] Each subject (or parent/legal guardian if appropriate) in
the care of the investigator provided written informed consent,
including HIPAA authorization, and the subject assented (if
appropriate) to participate in the study, before any study-related
procedures were performed. Investigators screened subjects at visit
1, seven to nine days before day 1 (visit 2) study drug
administration, to determine eligibility for enrollment.
Investigators reviewed and recorded subjects' relevant medical
history, including history of current disease and other pertinent
respiratory history, baseline signs and symptoms, inhaled dry
powder use and inhaled antibiotic use within 6 months before
screening, and current medications and therapies ongoing at
screening.
[0175] Investigators performed a screening physical examination of
subjects, including measures of height, body weight, and vital
signs. Vital signs included heart rate, respiratory rate, oral
temperature, and sitting arterial blood pressure. Heart rate and
respiratory rate were taken for 1 minute after the subject had
rested for at least 10 minutes. Blood pressures were measured while
the subject was seated after resting for at least 10 minutes.
[0176] All subjects whose regular medication regimen included
routine use of short-acting bronchodilators for clinical therapy at
least once or more daily for two weeks prior to screening were
administered a bronchodilator 15 to 30 minutes before a screening
spirometry test and 15 to 60 minutes before study drug
administration. Subjects on long-acting bronchodilators took the
medication as prescribed within 24 hours before study drug.
[0177] Subjects completed a routine spirometry test according to
the 1994 American Thoracic Society guidelines to measure forced
expiratory volume in 1 second (FEV.sub.1), forced vital capacity
(FVC), and mid-range forced expiratory flow rate (FEF.sub.25-75),
to document their ability to reliably perform spirometry, and to
ensure that they met the inclusion requirement that FEV.sub.1 equal
or exceed 40% of the predicted value, calculated using Knudson
equations based on gender, age, and height.
[0178] Subjects provided a blood sample for screening chemistry and
hematology tests and a urine sample for dipstick proteinuria
evaluation. Female subjects who were 11 years or older or who had
reached menarche provided a urine sample for pregnancy testing.
[0179] Subjects who satisfied all inclusion and exclusion
requirements were eligible to participate in the study and were
randomized to treatments as described in the protocol. Randomized
subjects were to return to the clinic 7 to 9 days later (visit 2)
to receive study treatment and treatment-related procedures.
[0180] At visit 2, before administration of day 1 study treatments,
all randomized subjects completed predose procedures, which
included assessments of change in baseline symptoms, change in
concomitant therapies, and measurement of vital signs.
Investigators performed a repeat physical examination if any of the
body systems were abnormal and clinically significant at screening
or if the subject had any clinically significant change in health
status from the time of screening. The urine dipstick test for
proteinuria was to be repeated before dosing, if trace or 1+ at
screening; serum chemistry and hematology were also to be repeated
if abnormal at screening. Investigators performed a predose
spirometry test (15 to 30 minutes after subjects' usual
short-acting bronchodilator, if applicable) and collected serum and
sputum samples for predose tobramycin assays.
[0181] Before administration of study treatments, TPI subjects
currently using a short-acting bronchodilator either regularly or
on demand could be pretreated with their short-acting
bronchodilator at the discretion of the investigator. Subjects not
currently using a short-acting bronchodilator could be pretreated
with one if they had a 10% or greater relative decline in FEV.sub.1
between the screening and pre-dose pulmonary function tests.
Relative percent change from screening in FEV.sub.1 was calculated
as follows.
Relative % FEV.sub.1 change from screening=[(predose
FEV.sub.1-screening FEV.sub.1)/screening FEV.sub.1].times.100
[0182] A single dose of study treatments was administered within 60
minutes after predose bronchodilator administration, if applicable,
or spirometry, and subjects were evaluated for aerosol delivery and
safety objectives of the protocol as described in following
sections. At the time of dosing, subjects were instructed to sit
upright, breathe normally, and use nose clips during inhalation of
study treatment. The research coordinator recorded start and stop
times for study treatment administration. If the subject
experienced prolonged cough (greater than 10 seconds), the research
coordinator stopped the timer and restarted it when the subject
resumed treatment. For TPI subjects, the Investigator and/or
research coordinator noted whether a rattling sound emanating from
the inhaler was heard on the second inhalation of the study drug.
Immediately after completing study drug administration, subjects
rinsed their mouths with 30 mL of normal saline, gargled for 5 to
10 seconds, and expectorated the rinse; this rinse procedure was
performed three times.
[0183] Subjects remained at the clinic to complete safety
assessments for 12 hours after the start of administration of study
treatments. Subjects were then discharged from the clinic and
scheduled to return to the clinic for visit 3 follow-up on day 8
(.+-.2 days). Flexible scheduling of follow-up visits due to
subject constraints (the follow-up visit is designated as "day 8"
throughout this Example was permitted). Slight deviations from the
protocol schedule were considered to have minimal or no effect on
the evaluation of study objectives.
[0184] During the day 8 follow-up visit, the research coordinator
reviewed any changes in subjects' medical history, including
concurrent illnesses, new or worsening adverse events,
CF-associated symptoms, current medications and dosages, and
over-the-counter medications. Subjects with clinically significant,
study drug-related adverse events (AEs) were followed with repeated
evaluations (either via phone or at clinic visits) until
satisfactory resolution. The investigator performed a physical
examination of the subject, measured height, weight, vital signs,
and spirometry results, and collected blood and urine specimens for
chemistry, hematology, and dipstick proteinuria tests.
[0185] Primary Aerosol Delivery Variable(s)
[0186] Estimation of the comparable dose of TPI to TOBI 300 mg/5 mL
was based on evaluation of the aerosol delivery characteristics of
the test treatment and the control treatment. Aerosol delivery
characteristics of test and control treatments were determined on
the basis of serum and sputum tobramycin concentrations over time,
calculation of certain serum and sputum pharmacokinetic parameters
as described in this Example, measurement of treatment
administration time, and evaluation of T-326 Inhaler device and
capsule performance.
[0187] Serum Tobramycin Concentrations
[0188] Blood samples were collected at predose and at 0.5, 1, 2, 4,
8, and 12 hours after the start of the first tidal breath during
inhalation of study treatment. Samples were to be collected as
close as possible to specified times and were considered to have
been drawn on time if collected within .+-.2 minutes of the
scheduled 0.5-hour posttreatment collection time and within .+-.10
minutes of scheduled times for the ensuing posttreatment
collections. Samples collected outside these intervals were
considered protocol deviations.
[0189] Serum was harvested and stored at -20.degree. C. or below
until analysis. Concentrations of tobramycin in serum were analyzed
with a modified fluorescence polarization immunoassay (FPIA) method
using the Abbott TDx.RTM./TDxFLx.RTM. System. Samples were added
directly to the dilution well of the sample cartridge. The net
polarization was acquired by the TDx/TDxFLx apparatus. A weighted
four-parameter logistic equation was used to calculate the
concentrations of tobramycin. The concentrations of tobramycin were
reported in terms of free base equivalents.
[0190] For assaying the subject samples of the study, calibration
standards (0.05, 0.10, 0.40, 0.80, and 0.90 .mu.g/mL) and quality
control samples (0.10, 0.40, and 0.80 .mu.g/mL) were prepared. The
assay was completed in 6 runs.
[0191] The lower limit of quantitation was 0.05 .mu.g/mL. The
precision of the assay, as reflected by the CV of the quality
control samples, was 4.9%, 5.7%, and 5.6% for the 0.10, 0.40, and
0.80 .mu.g/mL samples, respectively. The accuracy of the method,
reflected by the mean interassay recoveries of the quality control
samples, was 103%, 103%, and 101% for the 0.10, 0.40, and 0.80
.mu.g/mL samples, respectively. Overall, this method exhibited
suitable accuracy and precision for pharmacokinetic analysis.
[0192] Calculation of serum pharmacokinetic parameters and
estimation of the comparable dose of TPI are described in this
Example.
[0193] Sputum Tobramycin Concentrations
[0194] Sputum samples were expectorated by subjects from a deep
cough and collected before day 1 dosing (predose) and at 0.5, 1, 2,
4, 8, and 12 hours after the start of the first tidal breath during
inhalation of study treatment. Sputum samples were collected as
close as possible to specified times and within the same time
windows as the serum collections. Samples collected outside these
intervals were considered protocol deviations.
[0195] A sputum sample (minimum of 100 mg) was collected before the
single dose of study treatment to determine the baseline tobramycin
concentration.
[0196] Sputum samples were stored at -70.degree. C. or below until
analysis. The concentration of tobramycin was analyzed using a
validated, reverse-phase, high-performance liquid chromatography
(HPLC) method with ultraviolet detection.
[0197] Subject sputum samples were first liquefied with 1/5 normal
sodium hydroxide and diluted with Tris buffer (20.0 g Trizma
base/L). Sputum standard samples were prepared by spiking diluted
pooled sputum from CF subjects with tobramycin to final
concentrations of 0, 20, 40, 100, 200, 400, and 1000 .mu.g/g of
sputum. Assay quality control samples were prepared by spiking
diluted pooled sputum to contain 40, 300, and 800 .mu.g/g. The
internal standard sisomycin (100 .mu.L, 0.15 mg/mL in Tris buffer)
was added to 100 .mu.L of each standard, control, and subject
sample, followed by 400 .mu.L of acetonitrile and 50 .mu.L of
2,4-dinitrofluorobenzene (0.17 g/mL). The sample reaction mixtures
were heated in a dry-block heater for 1 h at 80.degree. C. After
addition of 600 .mu.L of 60/40 acetonitrile/water (v/v), 50 .mu.L
was analyzed by HPLC.
[0198] Samples were injected onto a Waters Nova-Pak.RTM. C-18,
3.9.times.150 mm, 4 .mu.m column connected to a Waters HPLC with
600E pump, 486 or 2487 ultraviolet detector (.lamda.max=360 nm) and
717 Plus autosampler. The mobile phase consisted of 0.2% acetic
acid in acetonitrile (39/61, v/v), pumped at a rate of 1.5 mL/min
for 5 min, 2.0 mL/min for an additional 9 or 10 min, depending on
the length of the run. Waters Millennium-32 C/S LC Software
(version 3.20) was used to operate the Waters HPLC instruments as
well as acquire raw data, process, compute, and report the
analytical results. The ratio of the peak height of tobramycin to
the internal standard sisomycin (PHR) was calculated. The assay was
completed in 17 runs.
[0199] Retention time ranges of 3.8 to 4.1 min and 10.0 to 10.6 min
were observed for tobramycin and sisomycin, respectively. A linear
relationship existed between PHR and concentration from 20 to 1000
.mu.g/g for sputum. The regression model was PHR=Bx+A (x=tobramycin
concentration), weighted 1/x. The lower limit of quantitation was
20 .mu.g/g. The concentrations of the standard samples were within
97 to 102% of the nominal concentration, with coefficients of
variation (CV) not higher than 5.2%. The precision of the assay, as
reflected by the CV of the quality control samples, was 5.2%, 3.9%
and 2.0%, for the 40, 300, and 800 .mu.g/g samples, respectively.
The accuracy of the method, reflected by the interassay recoveries
of the quality control samples, was 107%, 99%, and 97% for the 40,
300, and 800 .mu.g/g quality control samples, respectively.
Overall, this method exhibited suitable accuracy and precision for
pharmacokinetic analysis.
[0200] Treatment Administration Time
[0201] Treatment administration time was defined as the length of
time from the start of the subject's first inhalation to completion
of treatment administration. Treatment administration was complete
when the test T-326 Inhaler began to rattle and when the control
PARI LC PLUS nebulizer began to sputter. The investigator noted,
for TPI capsules, whether rattling was heard on the second breath
by the subject, an indication that the capsule had been
emptied.
[0202] If treatment administration was interrupted for any reason,
the time of interruption and start and stop times of continued
administration were to be recorded. If dosing was interrupted,
total treatment administration time was not to include the duration
of the interruption. If dosing was interrupted and either the stop
time at interruption or the dose restart time was missing,
treatment administration time was considered to be not
calculable.
[0203] Inspection and Residual Tobramycin Analyses of Used T-326
Inhaler Devices and TPI Capsules
[0204] Although not specified in the study protocol, used T-326
Inhaler devices and used TPI capsules were analyzed after use for
performance evaluation.
[0205] Adverse Events
[0206] An adverse event (AE) is defined as any untoward medical
occurrence in a clinical investigation subject administered a
pharmaceutical product, at any dose, that does not necessarily have
to have a causal relationship with this treatment. An AE could
therefore be any unfavorable and unintended sign (including
abnormal laboratory findings), symptom, or disease temporally
associated with the use of a medicinal product, whether or not
considered related to the medicinal product. This definition
includes intercurrent illnesses or injuries, and exacerbation of
pre-existing conditions. An unexpected AE is an event the nature or
severity of which is not consistent with the applicable product
information.
[0207] AEs may have been volunteered spontaneously by the subject
or discovered as a result of general questioning by the
investigator or research coordinator.
[0208] All AEs were to be monitored until resolution or, if the AE
was determined to be chronic, a cause was identified. If an AE
remained unresolved at the conclusion of the study, a clinical
assessment was to be made by the investigator and medical monitor
whether continued follow-up of the AE was warranted.
[0209] The severity of events reported on the AE CRF was determined
by the investigator as follows:
TABLE-US-00002 Mild: No limitation of usual activities. Moderate:
Some limitation of usual activities. Severe: Inability to carry out
usual activities.
[0210] The relationship of the study treatment to an AE was
determined by the investigator based on the following
definitions:
Not Related Exposure to the investigational product did not occur,
or the occurrence of the AE is not reasonably related in time, or
the AE is considered unlikely to be related to the investigational
product. Possibly Related The study product administration and the
AE were reasonably related in time, and the AE could be explained
equally well by causes other than exposure to the investigational
product. Probably Related: The study treatment and the AE were
reasonably related in time, and the AE was more likely explained by
exposure to the study product than by other causes, or the
investigational product was the most likely cause of the AE.
[0211] Serious Adverse Events (SAEs)
[0212] No SAEs were reported in this study.
[0213] Clinical Laboratory Tests
[0214] Laboratory tests to measure baseline hematology, serum
chemistry, and dipstick proteinuria were performed at the time of
screening and at the follow-up visit on day 8. At the dosing visit
on day 1, blood urea nitrogen (BUN) and serum creatinine were
measured 12 hours after the start of study drug administration. In
addition, the urine dipstick test for proteinuria was repeated
before dosing, if trace or 1+ at screening; serum chemistry and
hematology were also repeated if abnormal at screening.
[0215] Hematology tests performed for this study included white
blood cell count (WBC), red blood cell count (RBC), hemoglobin,
hematocrit, differential, and platelet count.
[0216] Serum chemistry tests performed included sodium, potassium,
chloride, bicarbonate, BUN, creatinine, glucose, calcium,
phosphorus, gamma glutamyl transferase (GGT), alanine transaminase
(ALT or SGPT), aspartate transaminase (AST or SGOT), alkaline
phosphatase, lactic dehydrogenase (LDH), total bilirubin, direct
bilirubin, indirect bilirubin, total protein, albumin, and serum
human chorionic gonadotrophin (HCG).
[0217] Bronchospasm and Spirometry
[0218] Spirometry testing (forced expiratory volume in one second
[FEV.sub.1 in liters], forced vital capacity [FVC in liters], and
forced expiratory flow rate during the middle two quarters of the
forced vital capacity [FEF.sub.25-75]) was performed before the day
1 single dose and at 30 minutes after completion of dosing to
assess airway response to study treatments. A routine spirometry
test was also performed at the day 8 follow-up visit.
[0219] The study protocol prospectively defined bronchospasm as a
relative decline of 20% or more in FEV.sub.1% predicted from
predose to 30 minutes after the end of dosing. Subjects with a
relative decline of 10% or more in FEV.sub.1% predicted were also
noted.
[0220] At 30 minutes after dosing, if the relative % FEV.sub.1
decline was 20% or more, spirometry (FEV.sub.1, FVC.sub.1 and
FEF.sub.25-75) measurements were to be repeated according to a
schedule defined by the investigator until the FEV.sub.1 decrease
was less than 10% (this was not done for subject 12/317, the only
subject who experienced a 20% or greater decline in FEV.sub.1
percent predicted). All instances of decline in FEV.sub.1%
predicted of 20% or more were to be recorded as AEs (this was not
done for subject 12/317). Treatment with appropriate medications
and further follow-up were at the discretion of the
investigator.
[0221] Vital Signs
[0222] Vital signs were measured before the day 1 dose and at 30
minutes and 1, 4, 8, and 12 hours after the start of dosing and
included sitting arterial blood pressure, heart rate, and
respiratory rate taken after 10 minutes rest, and body temperature.
Vital signs were also measured at the day 8 follow-up visit.
[0223] Physical Examinations
[0224] Physical examination of subjects was performed at the day 8
follow-up visit and consisted of physician review of subjects'
general appearance, skin, lymph nodes, HEENT, lungs,
cardiovascular, abdomen, extremities, musculoskeletal, neurologic,
and genitourinary (optional) body systems.
[0225] Appropriateness of Measurements
[0226] The measures of efficacy used in this study are standard,
i.e., widely used and generally recognized as reliable, accurate,
relevant, and discriminatory between effective and ineffective
agents. The measures of safety used in this study are standard
clinical and laboratory procedures.
[0227] Pharmacokinetics
[0228] The concentration (C) versus time (t) data from sputum and
serum tobramycin assays were analyzed by model-independent methods
to obtain the pharmacokinetic parameters. The maximum concentration
(C.sub.max) and the time to maximum concentration (t.sub.max) were
obtained by inspection. The terminal rate constants (.lamda..sub.z)
were determined by log-linear regression of the terminal phase. The
half-life was calculated as t.sub.1/2=ln(2)/.lamda..sub.z.
Concentrations below the lower limit of quantitation were treated
as zero for all calculations. The areas under the sputum and serum
concentration-time curves from time zero (predose) to 12 hours,
AUC(0,12), was calculated by the trapezoidal rule. The AUC to
infinity, AUC(0,.infin.), was calculated as
AUC(0,12)+C(12)/.lamda..sub.z where C(12) is the concentration 12 h
after the start of dosing.
[0229] All pharmacokinetic parameters were expressed as the mean
.+-.SD. A harmonic half-life was estimated as
t.sub.1/2=ln(2)/ .lamda..sub.z,
[0230] in which .lamda..sub.z is the arithmetic mean of the
terminal rate constants at each dose. The standard deviation of the
harmonic mean half-life, SD( t.sub.1/2), was obtained as
SD ( t 1 / 2 ) _ = ln ( 2 ) .lamda. z _ .times. SD ( .lamda. z ) _
.lamda. z _ , ##EQU00001##
[0231] where SD( .lamda..sub.z) is the standard error of the mean
terminal rate constant at each dose.
[0232] Estimation of the Comparable Dose of TPI to TOBI
[0233] A linear regression model was fitted for log AUC(0,12) vs.
log (TPI dose) of TPI serum concentration data from all cohorts to
estimate the comparable dose of TPI to TOBI. The comparable dose
and the 95% confidence interval were determined by taking the
inverse of the fitted regression line and the upper and lower 95%
confidence bands at the mean log AUC(0,12) of TOBI data.
[0234] Monitoring
[0235] The study was conducted according to the principles of Good
Clinical Practice (GCP).
[0236] Data Handling
[0237] Case report form data were entered in duplicate into a
Clintrial.RTM. database.
[0238] Data quality control was performed using Procedural
Language/Sequential Query Language (PL/SQL) and SAS.RTM. software
version 8.2 or higher (SAS Institute, Cary, N.C.). Analysis was
performed using SAS software version 8.2 or higher, based on a
predefined analysis plan. The estimated overall database error rate
was 0.022% with an upper 95% confidence limit of 0.157% (rounded).
This upper confidence limit is below the chosen standard of
0.5%.
[0239] Statistical Methods and Determination of Sample Size
[0240] The objectives of this phase 1 study were to assess the
safety of test TPI and control TOBI treatments and to estimate the
dose of TPI that would produce a comparable pharmacokinetic profile
to that of TOBI 300 mg/5 mL. There were no efficacy objectives
defined for this study. All planned summaries and analyses were
exploratory in nature. There were no planned statistical
comparisons between TPI and TOBI treatment groups and no planned
statistical hypothesis tests for differences between the two
treatments. Due to the small number of subjects available for
enrollment at each center, the Analysis Plan for the study
prospectively specified that data were to be pooled across centers
for analyses.
[0241] All summaries and analyses were produced for each of the six
treatment groups. Unless otherwise specified, frequencies and
percentages were calculated for categorical variables, and the
number of non-missing values, mean, standard deviation, minimum,
median, and maximum were calculated for continuous variables. All
data recorded on CRFs were presented in individual subject data
listings.
[0242] Three subject populations were defined. [0243] All-Enrolled
Population: subjects who were enrolled and randomized in the study.
[0244] Safety-Evaluable Population: subjects who were randomized
and took all or part of the prescribed study drug. [0245]
Pharmacokinetic-Evaluable Population: subjects who were randomized
and took all of the prescribed study drug.
[0246] Baseline and demographic characteristics were summarized for
the all-enrolled subject population. Assessments of the
pharmacokinetics of tobramycin were conducted using the
pharmacokinetic-evaluable population. Estimation of the dose of TPI
that provided systemic tobramycin exposure that was comparable to
TOBI was undertaken on the TPI comparable dose-evaluable
population. Analyses of all other variables were undertaken using
the safety-evaluable population.
[0247] SAS version 8.2 was used for all analyses. Microsoft Excel
was used for graphic display of study results.
[0248] Aerosol Delivery Analysis and Estimation of Comparable TPI
Dose
[0249] All subjects who received the single dose treatment were
included in the analysis and evaluation of aerosol delivery
characteristics, which were characterized on the basis of sputum
and serum tobramycin concentrations, estimated serum
pharmacokinetic parameters, and treatment administration time.
[0250] Serum AUC(0,12) was used to estimate the comparable TPI dose
to TOBI. A linear regression analysis with log AUC(0,12) as the
dependent variable and log (TPI dose) as the independent variable
was performed using the data from all TPI groups. The comparable
dose of TPI was determined by taking the inverse of the fitted
regression line at the mean log AUC(0,12) of TOBI serum tobramycin
concentrations from the five combined TOBI cohorts.
[0251] Secondary Aerosol Delivery Analyses
[0252] The study protocol identified no secondary aerosol delivery
variables.
[0253] Safety Analyses
[0254] All subjects who received a dose of study treatment were
evaluable for safety based on AEs, change in pulmonary function,
clinical laboratory results, vital signs, and physical
examinations.
[0255] Evaluation of Adverse Events
[0256] Baseline symptoms and treatment-emergent adverse events (AE)
were coded using the MedDRA thesaurus. The total incidence of
individual treatment-emergent AEs (percent of subjects who
experienced the event at least once during or after study
treatment) was evaluated descriptively for any noteworthy
differences between TPI and TOBI treatments. No statistical tests
were planned. AEs were also summarized by severity (mild, moderate,
severe) and drug relationship (unrelated, possibly related) for
test and control treatments. For drug relationship evaluations, the
classification, "possibly related", included individual AEs that
were judged to be probably related, possibly related, and of
unknown relationship to study treatment by the investigator.
[0257] Change in Pulmonary Function
[0258] Normal values have been developed for FEV.sub.1, FVC.sub.1
and FEF.sub.25-75 (spirometry measurements) if subjects are free of
pulmonary disease. These norms are commonly used in studies of
subjects with pulmonary disease. Raw spirometry measurements were
converted to normative percent predicted values using Knudson
Equations, as described below. For each subject, the Knudson
normative value for FEV.sub.1, FVC.sub.1 or FEF.sub.25-75 is a
linear combination of the subject age (years) and height (cm) using
the following formula:
Knudson Normative
Value=C.sub.0+C.sub.1.times.Height+C.sub.2.times.Age
where the coefficients C.sub.0, C.sub.1, and C.sub.2 are determined
based on subject gender and age group.
[0259] Given a raw observed value from spirometry measurements and
the Knudson normative value, the percent (%) predicted value is
calculated by:
% predicted value=(Raw Observed Value/Knudson Normative
Value).times.100
[0260] Change and relative change in FEV.sub.1% predicted
(FEV.sub.1%) from predose to 30 minutes postdose after the end of
dosing were calculated using the following formulae:
Change=Postdose FEV.sub.1%-Predose FEV.sub.1%
Relative change=[(Postdose FEV.sub.1%-Predose FEV.sub.1%)/Predose
FEV.sub.1%].times.100
[0261] A subject was defined as experiencing bronchospasm when the
relative change from baseline was a decline of .gtoreq.20%.
[0262] Change and relative change, and the incidence of
bronchospasm, were compared descriptively between treatment groups.
Additionally, the following variables were derived and summarized
similarly: [0263] the incidence of subjects with a relative decline
of 10% or more in FEV.sub.1% predicted from predose to 30 minutes
after the end of dosing [0264] changes and relative changes in FVC
% predicted and FEF.sub.25-75% predicted from predose to 30 minutes
after the end of dosing [0265] changes and relative changes in
FEV.sub.1% predicted, FVC % predicted, and FEF.sub.25-75% predicted
from predose to the day 8 follow-up visit.
[0266] Other Safety Variables
[0267] Other safety variables including clinical laboratory
results, vital signs, concomitant medications, medical procedures,
physical examinations were summarized descriptively. Additionally,
changes from baseline to end of study were calculated and
summarized for laboratory data, vital signs, and spirometry
measurements; in these calculations, the baseline value was the
last available assessment prior to study dosing. Changes in the
incidence of laboratory results that were below and above the
respective normal ranges were also evaluated.
[0268] Determination of Sample Size
[0269] The sample size and the choice of parallel design were
determined on the basis of clinical and practical rather than
statistical power considerations. All analyses were considered
exploratory and were undertaken using descriptive methods. No
inferential statistical analyses were planned for this study.
[0270] Interim Analyses
[0271] At the end of each study cohort, summaries of key safety
variables were produced and provided to the Data Monitoring
Committee (DMC) to review and decide on dose escalation. The
following results were listed by subject and summarized by
treatment following completion of each cohort to support the
deliberations by the DMC: [0272] subject demography; [0273]
FEV.sub.1 percent predicted before and after dosing and percent
change; [0274] serious adverse events; [0275] treatment-emergent
AEs; [0276] respiratory system treatment-emergent AEs.
[0277] This interim analysis procedure was designed solely to
support the review of safety and the decision about dose escalation
by the DMC. No statistical tests of study data were planned, and no
statistical alpha-level adjustments were required as a result of
interim safety and dose escalation reviews.
[0278] Screening, Enrollment and Randomization of Subjects
[0279] A total of 97 subjects were screened for the study by the 15
investigators.
[0280] Ninety of the 97 screened subjects met entrance criteria and
were enrolled (Table 2) and randomized to one of the six
treatments. Seven of the 97 screened subjects did not meet study
entry criteria and were not enrolled.
TABLE-US-00003 TABLE 2 Enrollment and Randomization by Site and
Treatment Total TPI Dosage Regimens TOBI subjects Site 2 .times. 14
mg 4 .times. 14 mg 2 .times. 28 mg 3 .times. 28 mg 4 .times. 28 mg
300 mg by site 01 3 1 2 1 3 10 02 3 2m 1 1 1 8 03 3 2 1 6 04 2 3 1
3 9 05 2 1 2 2 1 8 06 2 2 1 1 6 07 1 1 2 1 5 08 2 1 3 09 1 1 1 2 3
8 10 1 1 1 3 11 1 1 2 4 12 1 1 1 1 4 13 2 3 5 16 2 3 2 1 1 1 10 17
1 1 Total 12 14 15 15 14 20 90 enrolled and randomized
[0281] Withdrawal of Subjects Before Treatment
[0282] Three of the 90 enrolled subjects were withdrawn before
treatment due to predose AEs and did not receive the single dose of
study treatment (Table 2). Eighty-seven of the 90 subjects were
dosed with study treatment.
TABLE-US-00004 TABLE 3 Subjects Enrolled But Withdrawn Before Study
Treatment Reason Subject Did Not Receive Treatment Disposition
Study Treatment 4 .times. 14 mg Withdrawn before Predose AE:
wheezing. dose 2 .times. 28 mg Withdrawn before Predose AE: cough
aggravated. dose 4 .times. 28 mg Withdrawn before Predose AEs:
cough aggravated, laryngitis dose NOS, pyrexia.
[0283] Study Completion
[0284] Eighty-six of 87 subjects who were dosed with study
treatment completed the study. One of the 87 dosed subjects was
withdrawn from the study due to treatment-emergent AEs.
[0285] One of the 86 completing subjects was dosed, but evaluation
of returned capsules after the study revealed that the capsules had
not been pierced by the T-326 Inhaler. Serum tobramycin
concentrations in this subject were below quantifiable limits
(BQL), confirming that the subject received no study treatment.
[0286] Data Sets Analyzed for Aerosol Delivery Evaluation
[0287] Eighty-six of the 90 enrolled subjects were randomized, were
administered a single dose of study treatment, and were evaluable
for safety objectives of the protocol. Three of the 90 subjects
were withdrawn from the study due to AEs before they received study
treatment and were excluded from safety evaluations. One additional
subject did not receive any study treatment due to the failure of
the T-326 Inhaler to pierce the treatment capsules and was excluded
from safety evaluations.
TABLE-US-00005 TABLE 4 Subjects Not Evaluable for Safety
Evaluations Reason Subject Treatment Subject Disposition Not
Evaluable for Safety Objectives 2 .times. 14 mg Completed Subject
received no study treatment: capsule was not pierced, and
tobramycin was not detected in serum. 4 .times. 14 mg Withdrawn
before Predose AE: wheezing. dose 2 .times. 28 mg Withdrawn before
Predose AE: cough aggravated. dose 4 .times. 28 mg Withdrawn before
Predose AEs: cough aggravated, dose laryngitis NOS, pyrexia.
[0288] Eighty-four of the 86 subjects who received study treatment
were evaluable for pharmacokinetic objectives and estimation of the
TPI dose considered to be pharmacokinetically comparable to the
TOBI dose. Two of the treated subjects were excluded from
pharmacokinetic and comparable dose evaluations.
TABLE-US-00006 TABLE 5 Dosed Subjects Not Evaluable for
Pharmacokinetic Evaluations Subject Reason Subject Treatment
Disposition Inevaluable for Pharmacokinetic Objectives 2 .times. 28
mg Completed Did not receive full dose due to technical
complications with T-326 Inhaler; one full capsule was returned to
sponsor. 4 .times. 28 mg Withdrawn Did not receive full dose due to
AE mid- way through dosing, which led to withdrawal of consent and
withdrawal from the study; insufficient number of serum
samples.
[0289] Subjects who received no study treatment were also not
evaluable for pharmacokinetic evaluations.
[0290] Demographic Characteristics
[0291] Forty-three male and 47 female subjects, 7 to 50 years of
age, diagnosed with cystic fibrosis, were enrolled in the study.
Mean ages were similar among the treatment groups, ranging from
19.5 years in the TOBI group to 24.1 years in the TPI 2.times.14 mg
group. Fifteen subjects were 7 to 12 years of age, 22 subjects were
13 to 17 years, and 53 subjects were 18 to 50 years of age.
[0292] Seventy-nine subjects were Caucasian, five subjects were
Hispanic, three subjects were black, and three subjects were of
other origins. Gender and race distributions were similar between
TPI and TOBI treatment groups, although a small gender disparity
was noted between TPI 4.times.14 mg and TOBI groups (TPI: 11
female, 3 male subjects; TOBI: 8 female, 12 male subjects). The
effect of this imbalance on study results is uncertain.
[0293] On the average, TPI and TOBI subjects were comparable in
height and weight at screening.
[0294] Other Baseline Characteristics
[0295] Enrolled subjects had documented laboratory (sweat chloride
.gtoreq.60 mEq/L by quantitative pilocarpine iontophoresis test
(QPIT) and/or genotype with two identifiable mutations) and
clinical evidence consistent with a diagnosis of clinically stable
cystic fibrosis. Medical history findings and signs and symptoms
present before the start of the study were similar between the
treatment groups.
[0296] Other inclusion and exclusion criteria were satisfied. Of
note, four subjects experienced mild to moderate, persistent
haemoptysis that was present before day 1 dosing. All subjects met
the inclusion criterion of screening FEV.sub.1 being 40% or greater
of the predicted value based on sex, age, and height. The median
FEV.sub.1 percent predicted was similar for subjects in the six
treatment groups (from 58.51% in the TPI 2.times.14 mg group to
82.40% in the TPI 3.times.28 mg group and 67.95% in the TOBI
group). All but three subjects met the entry requirement to have a
dipstick urine protein result of less than 2+; three subjects did
not provide a urine sample at screening.
[0297] Thirty-nine of 90 enrolled subjects had received dry powder
via inhalation within the 6 months before screening, ranging from
25% to 60% of subjects per treatment group. Sixty-seven of 90
subjects had received TOBI (between 40% and 100% of subjects per
treatment group), none of the subjects had received other inhaled
aminoglycosides, and 10 of the 90 subjects had received other
inhaled antibiotics within the previous 6 months.
[0298] Thirty-six of the 90 enrolled (i.e., both TPI and TOBI
subjects) subjects used a short-acting bronchodilator as a part of
their standard CF treatment within 15 to 60 minutes before study
treatment. In two instances, bronchodilator use was more than 60
minutes before administration of study treatment.
[0299] Measurements of Treatment Compliance
[0300] Compliance with the single-dose treatment administration
requirements of the protocol was acceptable, as 86 of 90 enrolled
subjects received study treatment (three subjects withdrew before
dosing due to baseline symptoms, and one subject was dosed but
received no treatment because the T-326 device did not puncture the
treatment capsules). Four additional subjects had dosing
non-compliance events as listed in Table 6.
TABLE-US-00007 TABLE 6 Subjects With Dosing Non-Compliance Events
Treatment Disposition Dosing Non-Compliance Events 2 .times. 28 mg
Completed Capsule dropped; subject did not take inhalations from
1.sup.st capsule 4 .times. 28 mg Completed Site used one T-326
Inhaler, instead of two Inhalers, for 4 .times. 28 mg capsules.
High level (>45%) of TPI residual found in T-326 Inhaler due to
improper dosing. Completed Site used one T-326 Inhaler, instead of
two Inhalers, for 4 .times. 28 mg capsules. Completed Subject was
instructed to take one complete breath from 1.sup.st TPI capsule,
instead of two breaths.
[0301] Serum Tobramycin Concentrations and Pharmacokinetic
Parameters
[0302] As shown in FIG. 1, mean serum concentration-time profiles
of tobramycin after administration of TPI and TOBI indicate that
the drug is rapidly absorbed: median t.sub.max was 1 h in all
treatments. The distribution of the drug appears to be very fast,
and the levels declined in a monoexponential fashion, with average
terminal half-lives ranging between 2.8 and 3.5 h. The values of
the pharmacokinetic parameters of tobramycin after TOBI
administration are consistent with previous studies.
[0303] Increases in the dose of TPI led to increases in the
exposure to tobramycin, as evidenced by the increasing values of
AUC(0,.infin.), AUC(0,12), and C.sub.max (Table 8). These increases
were slightly less than proportional with dose).
[0304] Four subjects experienced cough, which caused an
interruption in dosing. The interruptions were seen at TPI doses
4.times.14 mg, 3.times.28 mg, and 4.times.28 mg. In all evaluable
subjects with cough, the values of AUC(0,.infin.), AUC(0,12), and
C.sub.max were within the range of other subjects in their dosing
group who completed dosing without interruption.
[0305] No differences in exposure to tobramycin, as measured by AUC
and C.sub.max, were detected between subjects receiving 4.times.14
mg manual-fill capsules vs. 2.times.28 mg automatic-fill capsules
(P>0.5). Therefore, the bioavailability of the hand- and
automatic-fill capsules was comparable, and these two groups were
consolidated.
[0306] In general, there was a weak negative correlation between
the percentage of powder left in the device and AUC(0,.infin.)
(r=-0.22, P=0.0771), AUC(0,12) (r=-0.23, P=0.0707), and C.sub.max
(r=-0.22, P=0.0838). Lower exposures were associated with higher
residual amounts of TPI in the device. One of the subjects in the
4.times.28 mg TPI dosing group (subject 04/409) had more than 45%
residual powder in the device and had exposures of tobramycin that
were among the lowest in his treatment group.
[0307] There were no significant correlations between change from
baseline in FEV.sub.1 and serum AUC and C.sub.max [for TPI
subjects: AUC(0,.infin.) (P=0.9838), AUC(0,12) (P=0.9990), and
C.sub.max (P=0.9110); for TOBI subjects: AUC(0,.infin.) (P=0.5216),
AUC(0,12) (P=0.4337), and C.sub.max (P=0.3878)].
TABLE-US-00008 TABLE 7 Selected Pharmacokinetic Parameters of
Tobramycin in Serum After Administration of TOBI (300 mg) and TPI
(28 mg, 56 mg, 84 mg, and 112 mg) TOBI TPI TPI TPI TPI TPI
Parameter 300 mg 2 .times. 14 mg 4 .times. 14 mg 2 .times. 28 mg 3
.times. 28 mg 4 .times. 28 mg AUC (0, .infin.) 5.3 .+-. 2.6 1.7
.+-. 0.6 3.1 .+-. 0.8 2.9 .+-. 1.2 4.1 .+-. 1.5 5.1 .+-. 2.0 (.mu.g
h/mL) AUC (0, 12) 4.8 .+-. 2.5 1.3 .+-. 0.6 2.8 .+-. 0.9 2.5 .+-.
1.2 3.5 .+-. 1.3 4.6 .+-. 2.0 (.mu.g h/mL) C.sub.max (.mu.g/mL)
1.04 .+-. 0.58 0.33 .+-. 0.09 0.56 .+-. 0.23 0.50 .+-. 0.21 0.70
.+-. 0.33 1.02 .+-. 0.53 t.sub.max.sup.a (h) 1 (0.5-2) 1 (0.5-2) 1
(0.5-1) 1 (0.5-2) 1 (1-2) 1 (0.5-2) t1/2 (h) 3.0 .+-. 0.8 2.8 .+-.
1.1 3.5 .+-. 0.8 3.3 .+-. 0.8 3.4 .+-. 1.0 3.1 .+-. 0.4 n PK 20 11
13 13 15 12 n total 20 12 13 14 15 13 .sup.amedian (range). Except
for number of subjects in last 2 rows, other entries are mean .+-.
standard deviation.
[0308] Comparable Dose Analysis of TPI and TOBI
[0309] The exposures achieved after administration of TOBI 300 mg
were very similar to that seen after administration of 4.times.28
mg capsules of TPI (FIGS. 2 and 3). When the AUC(0,12) data from
all cohorts was examined as a function of dose (FIG. 2), the
results indicate that a dose of 115 mg of TPI would produce a mean
AUC(0,12) similar to TOBI. When AUC(0,.infin.) was considered (FIG.
3), a dose of 112 mg would be expected to achieve a similar
AUC(0,.infin.) to TOBI. Based on these results, it appears that
four capsules of 28 mg of TPI (total dose of 112 mg) would produce
systemic exposure very close to that of TOBI.
[0310] Sputum Tobramycin Concentrations and Pharmacokinetic
Parameters
[0311] After administration of TPI and TOBI, maximum concentrations
in sputum were achieved on average at 30 min (FIG. 4), declining
thereafter with an average half-life of 0.8 to 2.2 h (Table 8).
[0312] The variability in pharmacokinetic parameters was higher in
sputum, as compared to serum. In addition to the inherent
variability in sputum-derived pharmacokinetic parameters, some
subjects were unable to produce sputum on demand (no more than
three subjects per group with a missing sputum sample at any one
time). This would have an impact on the calculation of exposure
measurements: AUC(0,.infin.), AUC(0,12), and C.sub.max. As a
consequence, while there is a trend of increasing exposure in
sputum with increases in dose, dose proportionality based on sputum
levels could not be confirmed.
TABLE-US-00009 TABLE 8 Selected Pharmacokinetic Parameters of
Tobramycin in Sputum after Administration of TOBI (300 mg) and TPI
(28 mg, 56 mg, and 112 mg) TOBI TPI TPI TPI TPI TPI Parameter 300
mg 2 .times. 14 mg 4 .times. 14 mg 2 .times. 28 mg 3 .times. 28 mg
4 .times. 28 mg AUC (0, .infin.) 1302 .+-. 1127 390 .+-. 139 1714
.+-. 1173 855 .+-. 469 2044 .+-. 1334 1740 .+-. 809 (.mu.g h/g) AUC
(0, 12) 974 .+-. 1143 261 .+-. 168 1195 .+-. 1224 652 .+-. 421 1340
.+-. 1320 1307 .+-. 978 (.mu.g h/g) C.sub.max (.mu.g/g) 737 .+-.
1028 258 .+-. 194 515 .+-. 421 574 .+-. 527 1092 .+-. 1052 1048
.+-. 1080 t.sub.max.sup.a (h) 0.5 (0.5-2.0) 0.5 (0.5-0.5) 0.5
(0.5-1.0) 0.5 (0.5-4.0) 0.5 (0.5-2.0) 0.5 (0.5-1.0) t1/2 (h) 1.7
.+-. 1.6 0.9 .+-. 0.8 1.8 .+-. 0.9 1.3 .+-. 1.5 0.8 .+-. 0.8 2.2
.+-. 1.7 n PK.sup.b 20 11 12 13 15 11 n total 20 12 13 14 15 13
.sup.amedian (range). Except for number of subjects in last 2 rows,
other entries are mean .+-. standard deviation. .sup.bn may be
different for different parameters. The maximum number of subjects
used in any single analysis is listed.
[0313] Study Drug Administration Time
[0314] Drug administration time averaged nearly 16 minutes in TOBI
subjects (Table 9). By comparison, administration time for two
capsules of TPI averaged 1.7 and 2.5 minutes for the 2.times.14 mg
and 2.times.28 mg doses, respectively. Administration times
averaged 4.2, 4.5, and 4.9 minutes for TPI 4.times.14 mg,
3.times.28 mg, and 4.times.28 mg doses, but in these cohorts a
second device was unpacked and utilized for dosing of the third and
fourth capsules, respectively. Thus, TPI administration time
increased primarily as the number of capsules increased and,
secondarily, as the dosage strength increased.
TABLE-US-00010 TABLE 9 Study Drug Administration Time TOBI TPI TPI
TPI TPI TPI 300 mg 2 .times. 14 mg 4 .times. 14 mg 2 .times. 28 mg
3 .times. 28 mg 4 .times. 28 mg Parameter (N = 20) (N = 11) (N =
13) (N = 14) (N = 15) (N = 13) Inhalation 15.8 .+-. 4.0 1.7 .+-.
0.6 4.2 .+-. 1.4 2.5 .+-. 1.1 4.5 .+-. 1.1 4.9 .+-. 1.8 Time (min):
Mean .+-. SD
[0315] Evaluation of T-326 Inhaler and TPI Capsule Performance
[0316] All but two TPI capsules were administered as required
(exception: 3.sup.rd and 4.sup.th capsules for one subject in the
TPI 4.times.28 mg group). Rattling was heard on the second breath
in 85% or more of the capsules.
[0317] There were no device failures reported by the sites or upon
inspection by the Nektar analysts. The sum of the residual
tobramycin in the subjects' inhaler(s) and capsules averaged 10.5%
of the nominal dose. This analysis included subject 04/409, who had
more than 45% residual powder in the device due to improper dosing,
so more than likely, the actual amount of residual powder in the
device was less.
[0318] Handling of Dropouts or Missing Data
[0319] During the study, three randomized subjects withdrew before
they received study treatment due to predose AEs. Another
randomized subject completed the study but was later found to have
not inhaled study treatment because both TPI capsules were not
pierced. Screening and enrollment continued until these subjects
were replaced; replacement subjects were assigned the next
available subject number in the randomization code.
[0320] One subject withdrew prematurely from the study. No
last-result-carried-forward (LRCF) strategy was employed in the
analyses to account for the early withdrawal.
[0321] Tobramycin concentrations below the lower limit of
quantitation were treated as zero for all calculations.
[0322] Use of an "Aerosol Delivery Subset" of Subjects
[0323] The protocol indicated that subjects who were randomized and
who took the complete dose of study treatment were evaluable for
pharmacokinetics. As the study proceeded, unanticipated dosing and
TPI capsule status issues led to revision of the evaluability
criteria for pharmacokinetics. A total of six subjects were
excluded from pharmacokinetic and comparable dose analyses (four
subjects received no study treatment, and two subjects did not
receive the full dose of study treatment). Eighty-four subjects
were evaluable for pharmacokinetic and comparable dose
evaluations.
[0324] All 86 enrolled subjects who were administered study
treatments by inhalation were included in the evaluation of study
treatment administration time and in the evaluation of residual
tobramycin in capsules and T-326 Inhalers.
[0325] Active-Control Studies Intended to Show Equivalence
[0326] The study was not designed or powered to show clinical or
pharmacokinetic equivalence between the test product and the
control.
[0327] Examination of Subgroups
[0328] The following subgroup analyses were performed on
dose-normalized serum exposure (AUC(0,12), AUC(0,.infin.), and
C.sub.max) of tobramycin after administration of TPI: [0329]
subjects less than 12 years old vs. subjects 12 and older
(P>0.4); [0330] previous dry powder users vs. nonusers
(P>0.8); [0331] males and females (P>0.1); [0332] body weight
(P>0.2).
[0333] None of these variables appeared to influence the exposure
of tobramycin.
[0334] The exposure of tobramycin, as measured by AUC and
C.sub.max, in TPI subjects (N=27) using bronchodilators from 15 to
60 minutes after dosing was slightly higher than in subjects not
using them (N=37). AUC(0,.infin.), AUC(0,12), and C.sub.max values
were 19% (P=0.0685), 27% (P=0.0240), and 38% (P=0.0038) higher.
Bronchodilator use may increase the amount of the tobramycin that
eventually reaches systemic circulation, perhaps by an increase in
the amount deposited in the lungs.
[0335] Aerosol Delivery Summary
[0336] Mean serum concentration-time profiles of tobramycin after
administration of TPI and TOBI indicate that the drug is rapidly
absorbed: t.sub.max was 1 hour in all treatments. The distribution
of the drug appears to be very fast, and the levels declined in a
monoexponential fashion, with average terminal half-lives ranging
between 2.8 and 3.5 hours. The values of the pharmacokinetic
parameters of tobramycin after TOBI administration are consistent
with previous studies.
[0337] Increases in the dose of TPI led to increases in the
exposure to tobramycin, as evidenced by the increasing values of
AUC(0,.infin.), AUC(0,12), and C.sub.max. These increases were
slightly less than proportional to dose. No differences in exposure
to tobramycin were detected between subjects receiving 4.times.14
mg manual-fill capsules vs. 2.times.28 mg automatic-fill capsules.
Therefore, these two groups were consolidated for the comparable
dose analyses. In general, there was a weak negative correlation
between the percentage of powder left in the device and
AUC(0,.infin.) (P=0.0707), AUC(0,12) (P=0.0771), and C.sub.max
(P=0.0838). There were no significant correlations between changes
in FEV.sub.1 from baseline and AUC(0,.infin.) (P=0.9838), AUC(0,12)
(P=0.9990), and C.sub.max (P=0.9110).
[0338] The exposures achieved after administration of TOBI 300 mg
were between the exposures seen after administration of 3.times.28
mg and 4.times.28 mg capsules of TPI. Based on the results, it
appears that four capsules of 28 mg of TPI (total dose of 112 mg)
produce the closest systemic exposure to TOBI.
[0339] Subgroup analyses in TPI subjects showed that age, previous
dry powder use, sex, and body weight did not influence the exposure
to tobramycin in TPI, indicating that the pharmacokinetics of
tobramycin is similar in these TPI subgroups. The exposure to
tobramycin in TPI subjects using bronchodilators (N=27) was
slightly higher on the average than in TPI subjects not receiving
bronchodilators (N=37).
[0340] After administration of TPI and TOBI, maximum concentrations
in sputum were achieved on average at 30 min, and average estimates
of half-life ranged from 0.8 to 2.2 hours.
[0341] The variability in pharmacokinetic parameters was higher in
sputum than in serum.
[0342] Drug administration time averaged nearly 16 minutes in TOBI
subjects. By comparison, administration time for two capsules of
TPI averaged 1.7 and 2.5 minutes for the 2.times.14 mg and
2.times.28 mg doses, respectively; administration times averaged
4.2, 4.5, and 4.9 minutes for TPI 4.times.14 mg, 3.times.28 mg, and
4.times.28 mg doses. Thus, TPI administration time increased
primarily as the number of capsules increased and, secondarily, as
the dosage strength increased.
[0343] Extent of Exposure
[0344] Eighty-six of 90 enrolled subjects received a single dose of
study treatments, as summarized below. [0345] 12 subjects received
up to 28 mg of TPI in a 2.times.14 mg single dose [0346] 13
subjects received up to 56 mg of TPI in a 4.times.14 mg single dose
[0347] 14 subjects received up to 56 mg of TPI in a 2.times.28 mg
single dose [0348] 15 subjects received up to 84 mg of TPI in a
3.times.28 mg single dose [0349] 13 subjects received up to 112 mg
of TPI in a 4.times.28 mg single dose [0350] 20 subjects received
up to 300 mg of TOBI in 5 mL single dose of a 60 mg/mL solution
[0351] Brief Summary of Adverse Events
[0352] More TPI subjects (40 of 66 subjects, 60.6%) than TOBI
subjects (6 of 20, 30.0%) experienced treatment-emergent AEs during
or after administration of single-dose study treatments. The
percent of subjects with any AE was similar among the TPI dose
levels (TPI 2.times.14 mg=45%; 4.times.14 mg=54%, 2.times.28
mg=64%, 3.times.28 mg=67%, 4.times.28 mg=69%); sample sizes were
too small to determine whether a trend was present for increasing
any-AE incidence with increasing TPI dose. All treatment-emergent
AEs were mild or moderate in intensity.
[0353] One TPI 4.times.28 mg subject experienced moderate cough and
sputum increased on day 2 which persisted and led to
hospitalization on the eighth day after the single-dose study
treatment was administered. Therefore, on day 8 after the subject
completed the study, these AEs were determined to be SAEs. Neither
of these SAEs, which occurred in the same subject, was considered
related to TPI treatment. Another TPI 4.times.28 mg subject
experienced the non-serious AEs of moderate, probably-related cough
aggravated, dysgeusia, and lacrimation increased that caused study
drug administration to be interrupted and then stopped; the subject
then withdrew consent and was withdrawn from the study. Four
subjects experienced non-serious AEs of coughing during inhalation
of TPI that led to a modification, interruption, or delay in dosing
(one subject each at TPI 4.times.14 mg and 4.times.28 mg and two
subjects at 3.times.28 mg); each AE was considered to be probably
related to TPI treatment by the investigator.
[0354] AEs experienced by the largest number of TPI subjects were
cough or cough aggravated (13 of 66 subjects=19.7%; 12 of the 13
TPI subjects previously reported cough as a baseline symptom before
the start of study treatment); dysgeusia (11 subjects, 16.7%);
pharyngitis, haemoptysis, and rhinorrhea (4 subjects, 6.1% each);
sputum increased, crackles lung, lacrimation increased, abdominal
pain upper, dizziness, headache NOS, and throat irritation (3
subjects, 4.5% each). The incidence of cough, cough aggravated, and
dysgeusia increased slightly with increasing TPI dose, but no
conclusive trend in the incidence of any individual AE was observed
in the data. By comparison, no more than one TOBI subject
experienced any AE. TOBI subjects experienced no cough, cough
aggravated, or dysgeusia. However, most subjects dosed with TOBI
(17 of 20, 85%) received TOBI as part of their usual therapy.
[0355] The investigators considered most instances of cough and
cough aggravated, all instances of dysgeusia, and most instances of
haemoptysis and throat irritation to be possibly or probably
related to TPI treatment. By comparison, single instances of chest
tightness, herpes simplex, eosinophil count increased, dry throat,
pharyngitis, sputum increased, and sputum viscosity increased were
considered related to TOBI treatment.
[0356] Treatment-Emergent Adverse Events: All Causes
[0357] Forty of 66 TPI subjects and six of 20 TOBI subjects
experienced treatment-emergent AEs during or after treatment. The
percent of subjects with any AE was similar among the TPI dose
levels. All treatment-emergent AEs were mild or moderate in
intensity.
[0358] AEs experienced by the largest number of TPI subjects were
cough or cough aggravated (13 of 66 subjects=19.7%); dysgeusia (11
subjects, 16.7%); pharyngitis, haemoptysis, and rhinorrhea (4
subjects, 6.1% each); sputum increased, crackles lung, lacrimation
increased, abdominal pain upper, dizziness, headache NOS, and
throat irritation (3 subjects, 4.5% each).
[0359] No more than one TOBI subject experienced any AE. TOBI
subjects experienced no cough, cough aggravated, or dysgeusia.
[0360] Treatment-Emergent Adverse Events Considered Related to
Treatments
[0361] Twenty-four of 66 TPI subjects (36.4%) and 2 of 20 TOBI
subjects (10%) had AEs that were considered to be possibly or
probably related to treatments by the investigators (Table 12). The
investigators considered most instances of cough and cough
aggravated (10 of 66 TPI subjects=15.2%) and all instances of
dysgeusia (16.7%) to be possibly or probably related to TPI
treatment (Table 11). Haemoptysis and throat irritation (both 4.5%)
and lacrimation increased (3.0%) were also considered related to
TPI treatment. By comparison, single instances of chest tightness,
herpes simplex, eosinophil count increased, dry throat,
pharyngitis, sputum increased, and sputum viscosity increased were
considered related to TOBI treatment.
[0362] Other Serious Adverse Events
[0363] One TPI 4.times.28 mg subject experienced SAEs on day 2
(moderate cough and sputum increased) that led to hospitalization
for exacerbation of CF lung disease on the eighth day after the
single-dose study treatment. Neither of these SAEs, which occurred
in the same subject, was considered related to TPI treatment.
[0364] Withdrawal of Subjects from the Study Due to
Treatment-Related Adverse Events
[0365] One TPI 4.times.28 mg subject experienced moderate cough
aggravated, dysgeusia, and lacrimation increased that caused study
drug administration to be interrupted and then stopped, and the
subject was withdrawn from the study. Each AE was considered to be
probably related to TPI treatment by the investigator.
[0366] Dose Interventions Due to Treatment-Related Adverse
Events
[0367] Four subjects experienced coughs that led to a modification,
interruption, or delay in dosing (one subject each at TPI
4.times.14 mg and 4.times.28 mg and two subjects at 3.times.28 mg.
Each AE was considered to be probably related to TPI treatment by
the investigator.
TABLE-US-00011 TABLE 10 Dose Interventions Due to Adverse Events
Study Treatment Day of Subject Drug (Sex/Age).sup.b AE.sup.a
Adverse event.sup.a Dose interrupt.sup.a SAE.sup.a withdrew.sup.c
related.sup.a TPI 4 .times. 14 mg 1 Cough aggravated Modified No No
Probable (F/11) TPI 3 .times. 28 mg 1 Cough Modified No No Probable
(F/13) (F/25) 1 Cough Modified No No Probable TPI 4 .times. 28 mg 1
Cough aggravated, throat Modified No No Probable (F/22)
irritation
[0368] Analysis and Discussion of Deaths, Other Serious Adverse
Events, and Other Significant Adverse Events
[0369] No deaths were reported in this study. The only SAEs were
moderate cough and sputum increased reported by a single subject on
day 2, leading to hospitalization on day 8 after the subject
completed the study; these events were considered unrelated to
study treatment. Five TPI subjects developed moderate cough or
cough aggravated within minutes after inhalation of TPI, which led
one subject (who also had dysgeusia and increased lacrimation) to
withdraw from the study and four subjects to interrupt dosing. All
subjects reported baseline respiratory symptoms, and, of those who
reported cough as an AE, all but one also noted it as a baseline
symptom. These AEs resolved within 5 to 35 minutes with no or
minimal intervention. The four latter subjects restarted and
successfully completed dosing within minutes of the original
interruptions. These AEs were probably related to the underlying
bronchial irritability that often accompanies cystic fibrosis,
although the investigator considered each event to be probably
related to study drug administration. Thus, in this study, TPI at
each dose level and TOBI 300 mg/5 mL were well-tolerated.
[0370] Hematology
[0371] No notable mean changes from baseline to follow-up
hematology results were observed in TOBI or TPI treatment groups.
There were no important differences between TOBI and TPI groups in
mean change from baseline and no patterns of increasing mean change
with increasing dose of TPI for any hematology test.
[0372] No notable increases from baseline to follow-up were
observed for TOBI or TPI groups in the frequencies of above-normal
or below-normal hematology results. There were no important
differences between TOBI and TPI groups and no patterns of
increasing frequencies of outlier hematology results with
increasing dose of TPI.
[0373] One TOBI subject had a clinically significant follow-up
eosinophil count that was recorded as an AE.
[0374] Serum Chemistry
[0375] No notable mean changes from baseline to follow-up serum
chemistry results were observed in TOBI or TPI treatment groups.
There were no important differences between TOBI and TPI groups in
mean change from baseline and no patterns of increasing mean change
with increasing dose of TPI for any chemistry test.
[0376] No notable increases from baseline to follow-up were
observed for TOBI or TPI groups in the frequencies of above-normal
or below-normal serum chemistry results. There were no important
differences between TOBI and TPI groups and no patterns of
increasing frequencies of outlier chemistry results with increasing
dose of TPI.
[0377] One subject had a clinically significant follow-up glucose
result; this result was attributed to CF-related diabetes, was not
recorded as an AE, and was not attributed to TPI treatment.
[0378] Dipstick Urine Protein
[0379] Quantitative changes from baseline to follow-up results were
not calculated since the dipstick urine protein test is a
qualitative test. No notable increases from baseline to follow-up
were observed for TOBI or TPI groups in the frequency of dipstick
urine protein results of positive 2+ or greater.
[0380] A single positive 3+ result was noted in a subject who
received TPI 4.times.28 mg dose.
[0381] Individual Hematology Abnormalities
[0382] With one exception, no clinically significant hematology
results were observed during the study. TOBI subject 12/405 had a
clinically significant follow-up eosinophil result of 9.0% (normal
range, 0 to 6%) that was recorded as an AE and was considered
possibly related to TOBI treatment by the investigator. The
subject's baseline eosinophil result was at the upper limit of
normal (5.9%), but the subject had elevated eosinophils 8 days
before the baseline result. The clinical importance of the final
eosinophil result of 9.0% is uncertain.
[0383] Serum Chemistry
[0384] With one exception, no clinically significant serum
chemistry results were observed during the study. One subject (TPI
3.times.28 mg) had a clinically significant follow-up glucose
result; this result was attributed to CF-related diabetes.
[0385] Dipstick Urine Protein
[0386] With one exception, no clinically significant dipstick urine
protein results were observed during the study. One subject (TPI
4.times.28 mg) had a positive 3+ result at day 6 follow-up; the
subject had a positive 1+ result at screening and at an unscheduled
repeat test on the day of dosing. The study coordinator felt that
the 3+ urine protein result was consistent with SAEs (cough and
sputum increased) beginning on day 2 that led to hospitalization of
the subject.
[0387] Bronchospasm and Acute Decrease in Pulmonary Function
[0388] A single instance of asymptomatic bronchospasm (20.9%
reduction in FEV.sub.1 percent predicted within 30 minutes after
the subject inhaled a single dose of TPI 2.times.28 mg; (Table 11)
was observed during a spirometry procedure that was not performed
according to American Thoracic Society (ATS) specifications. Had
the procedure been performed to specification, the FEV.sub.1
reduction could have been less (11%). A similar asymptomatic
reduction in FEV.sub.1 percent predicted was also observed in a
TOBI subject (19.1% decrease).
[0389] One other TOBI subject and six other TPI subjects
experienced a decrease of more than 10% but less than 20% in
FEV.sub.1 percent predicted (Table 11). Three of the six TPI
subjects (subject 02/507 at the TPI 3.times.28 mg dose and subjects
01/415 and 08/406 at the TPI 4.times.28 mg dose) experienced cough
or cough aggravated within minutes after dosing.
TABLE-US-00012 TABLE 11 Subjects with Acute Decreases in Pulmonary
Function Associated AEs (especially 30-minute cough, wheeze,
Predose Postdose Percent Change or dyspnea) FEV.sub.1 % FEV.sub.1 %
in FEV.sub.1 % before/during Treatment Predicted Predicted
Predicted spirometry? TPI 52.3 44.3 -15.3.sup.a No 4 .times. 14 mg
TPI 69.9 55.3 -20.9.sup.b No 2 .times. 28 mg TPI 54.3 47.6
-12.3.sup.a No 3 .times. 28 mg 87.4 77.1 -11.8.sup.a Cough at time
of spirometry TPI 73.3 64.0 -12.7.sup.a Cough 4 .times. 28 mg
aggravated, lacrimation increased at time of spirometry 77.2 67.8
-12.1.sup.a No 67.8 60.0 -11.4.sup.a Cough aggravated, dizziness
ending about 30 minutes before spirometry TOBI 39.3 34.1
-13.2.sup.a No 300 mg 104.3 84.3 -19.1.sup.a No .sup.aDecrease in
FEV.sub.1 % predicted is 10% or more but less than 20%.
.sup.bDecrease in FEV.sub.1 % predicted is 20% or more.
[0390] Quantitative Changes in Pulmonary Function
[0391] Mean changes in FEV.sub.1 percent predicted, FVC percent
predicted, and FEF.sub.25-75 percent predicted in TOBI and all TPI
groups were relatively stable from screening to before day 1 dosing
and from predose day 1 to day 8 follow-up. There were no apparent
differences between TOBI and TPI groups, and no apparent
dose-related differences between TPI groups, in mean changes in
FEV.sub.1, FVC.sub.1 or FEF.sub.25-75 percent predicted from before
to 30 minutes after dosing.
[0392] Vital Signs
[0393] There were no large or consistent differences between TPI
and TOBI groups in vital signs or changes in vital signs throughout
the study.
[0394] Concomitant Medications
[0395] Thirty-eight of 90 subjects took concomitant medications and
therapies after dosing. No differences were apparent in the
frequencies or types of concomitant medications and therapies.
[0396] Safety Conclusions
[0397] More TPI subjects (60.6%) than TOBI subjects (30.0%)
experienced treatment-emergent AEs during or after treatment. The
percent of subjects with any AE was similar among the TPI dose
levels (45% to 69%); sample sizes were too small to determine
whether a trend was present for increasing any-AE incidence with
increasing TPI dose. All treatment-emergent AEs were mild or
moderate in intensity.
[0398] One TPI 4.times.28 mg subject experienced two SAEs (moderate
cough and sputum increased indicative of an exacerbation of CF lung
disease) that led to hospitalization on the eighth day after the
single-dose study treatment was administered; neither of these SAEs
was considered related to TPI treatment. Another TPI 4.times.28 mg
subject experienced moderate, probably-related cough aggravated,
dysgeusia, and lacrimation increased that caused study drug
administration to be interrupted and then stopped; the subject then
withdrew consent and was withdrawn from the study. Four subjects
experienced coughing during inhalation of TPI that led to a
modification, interruption, or delay in dosing (one subject each at
TPI 4.times.14 mg and 4.times.28 mg and two subjects at 3.times.28
mg); each AE was considered to be probably related to TPI treatment
by the investigator. However, in all four cases, dosing was only
interrupted briefly, and the subjects resumed and completed dosing
without mishap. All subjects in this study reported respiratory
baseline symptoms, with .about.90% in each cohort reporting cough.
Furthermore the reporting of mild cough is not unexpected from the
first administration of a dry powder inhaler, especially when
airway irritability is already present.
[0399] AEs experienced by the largest number of TPI subjects were
cough or cough aggravated (13 of 66 subjects=19.7%); dysgeusia (11
subjects, 16.7%); pharyngitis, haemoptysis, and rhinorrhea (4
subjects, 6.1% each); sputum increased, crackles lung, lacrimation
increased, abdominal pain upper, dizziness, headache NOS, and
throat irritation (3 subjects, 4.5% each). The incidence of cough,
cough aggravated, and dysgeusia increased slightly with increasing
TPI dose. No more than one TOBI subject experienced any AE. TOBI
subjects experienced no cough, cough aggravated, or dysgeusia, but
85% of the TOBI recipients were chronic TOBI users.
[0400] The investigators considered most instances of cough and
cough aggravated, all instances of dysgeusia, and most instances of
haemoptysis and throat irritation to be possibly or probably
related to TPI treatment. By comparison, single instances of chest
tightness, herpes simplex, eosinophil count increased, dry throat,
pharyngitis, sputum increased, and sputum viscosity increased were
considered related to TOBI treatment.
[0401] A single instance of asymptomatic bronchospasm (20.9%
reduction in FEV.sub.1) was recorded, similar to an asymptomatic
19.1% reduction in a TOBI subject.
[0402] There were no notable changes from baseline in clinical
laboratory results, no patterns of increasing change with
increasing dose of TPI, no increases in the frequency of
above-normal or below-normal results, and no apparent TPI vs. TOBI
differences. In a single TOBI subject, an elevated eosinophil count
was recorded as an AE.
[0403] Discussion and Overall Conclusions
[0404] Single dose administration of TPI results in a more
efficient delivery of tobramycin than TOBI.RTM. Tobramycin Solution
for Inhalation, while maintaining similar tobramycin
pharmacokinetics. Systemic exposures achieved after administration
of TOBI.RTM. Tobramycin Solution for Inhalation were very similar
to that seen after administration of 4.times.28 mg capsules of TPI,
with an equivalent dose calculation of 115 mg of TPI. Hence, four
capsules of 28 mg TPI (112 mg total) should produce systemic
exposures that are comparable to 300 mg of TOBI.RTM. Tobramycin
Solution for Inhalation.
[0405] Minimal dosing interruptions (temporary in all but one case)
due to cough were observed and did not appear to alter the single
dose pharmacokinetics of tobramycin in serum after administration
of TPI.
[0406] Approximately 20% of subjects reported cough with TPI, in
most cases mild, occasionally causing brief dose interruption, and
generally settling quickly. Cough is an expected AE with all
inhaled dry powder therapy and was present in the majority of
subjects at baseline. While the incidence of AEs was higher in
TPI-treated than TOBI-treated subjects, the majority of subjects in
most cohorts received chronic cycling TOBI.RTM. Tobramycin Solution
for Inhalation.
[0407] In one case, a young subject forgot to take his usual
medication (consisting of a long-acting bronchodilator) and
experienced moderate cough after dosing, which led to his
withdrawal. The loss of usual bronchoprotection is likely the cause
of this reaction.
[0408] Administration of single doses of TPI in total doses of 28
mg to 112 mg was well-tolerated by CF subjects during the study.
One hundred twelve milligrams of TPI powder gives a close systemic
exposure to tobramycin to that from TOBI.RTM. Tobramycin Solution
for Inhalation.
[0409] This study demonstrated that the inhalation using the
methods of the invention with a simple inhaler device is much more
rapid and efficient than the standard dose of TOBI.RTM. Tobramycin
Solution for Inhalation by nebulization. The side effects of
increased cough and throat irritation after inhalation of TPI were
not unexpected, given the amount of powder contained in each dose.
However, in most cases the effects were mild, and the subjects
voiced an appreciation for how quick and simple the dosing was for
TPI. The lack of complaint of cough and bad taste from the
TOBI.RTM. Tobramycin Solution for Inhalation group may be related
to the fact that 85% of those subjects had been taking TOBI.RTM.
Tobramycin Solution for Inhalation on a routine basis prior to the
study. These subjects may have acclimated to the effects of the wet
aerosol form of tobramycin.
[0410] Thus, single dose administration of dry powder tobramycin
resulted in a more efficient delivery of tobramycin than TOBI.RTM.
Tobramycin Solution for Inhalation, while maintaining similar
tobramycin pharmacokinetics. Systemic exposures achieved after
administration of TOBI.RTM. Tobramycin Solution for Inhalation were
very similar to that seen after administration of 4.times.28 mg
capsules of TIP, with an equivalent dose calculation of 115 mg of
TIP. Hence, four capsules of 28 mg TIP (112 mg total) should
produce systemic exposures that are comparable to 300 mg of
TOBI.RTM. Tobramycin Solution for Inhalation.
[0411] While the preferred embodiment of the invention has been
illustrated and described, it will be appreciated that various
changes can be made therein without departing from the spirit and
scope of the invention.
* * * * *