CLINICAL PHARMACOLOGY
Mechanism Of Action
Azelastine hydrochloride, a
phthalazinone derivative, exhibits histamine H1-receptor antagonist activity in
isolated tissues, animal models, and humans. ASTEPRO is administered as a
racemic mixture with no difference in pharmacologic activity noted between the
enantiomers in in vitro studies. The major metabolite, desmethylazelastine,
also possesses H1-receptor antagonist activity.
Pharmacodynamics
Cardiac Effects
In a placebo-controlled trial (95 patients with allergic
rhinitis), there was no evidence of an effect of azelastine hydrochloride nasal
spray (2 sprays per nostril twice daily for 56 days) on cardiac repolarization
as represented by the corrected QT interval (QTc) of the electrocardiogram.
Following multiple dose oral administration of azelastine 4 mg or 8 mg twice
daily, the mean change in QTc was 7.2 msec and 3.6 msec, respectively.
Interaction studies investigating the cardiac
repolarization effects of concomitantly administered oral azelastine
hydrochloride and erythromycin or ketoconazole were conducted. Oral
erythromycin had no effect on azelastine pharmacokinetics or QTc based on
analysis of serial electrocardiograms. Ketoconazole interfered with the
measurement of azelastine plasma levels; however, no effects on QTc were
observed [see DRUG INTERACTIONS].
Pharmacokinetics
Absorption
After intranasal administration of 2 sprays per nostril
(548 mcg total dose) of ASTEPRO 0.1%, the mean azelastine peak plasma
concentration (Cmax) is 200 pg/mL, the mean extent of systemic exposure (AUC)
is 5122 pg•hr/mL and the median time to reach Cmax (tmax) is 3 hours. After
intranasal administration of 2 sprays per nostril (822 mcg total dose) of
ASTEPRO 0.15%, the mean azelastine peak plasma concentration (Cmax) is 409
pg/mL, the mean extent of systemic exposure (AUC) is 9312 pg•hr/mL and the
median time to reach Cmax (tmax) is 4 hours. The systemic bioavailability of
azelastine hydrochloride is approximately 40% after intranasal administration.
Distribution
Based on intravenous and oral administration, the
steady-state volume of distribution of azelastine is 14.5 L/kg. In vitro studies
with human plasma indicate that the plasma protein binding of azelastine and
its metabolite, desmethylazelastine, are approximately 88% and 97%,
respectively.
Metabolism
Azelastine is oxidatively metabolized to the principal
active metabolite, desmethylazelastine, by the cytochrome P450 enzyme system.
The specific P450 isoforms responsible for the biotransformation of azelastine
have not been identified. After a single-dose, intranasal administration of
ASTEPRO 0.1% (548 mcg total dose), the mean desmethylazelastine Cmax is 23
pg/mL, the AUC is 2131 pg•hr/mL and the median tmax is 24 hours. After a
single-dose, intranasal administration of ASTEPRO 0.15% (822 mcg total dose),
the mean desmethylazelastine Cmax is 38 pg/mL, the AUC is 3824 pg•hr/mL and the
median tmax is 24 hours. After intranasal dosing of azelastine to steady-state,
plasma concentrations of desmethylazelastine range from 20-50% of azelastine
concentrations.
Elimination
Following intranasal administration of ASTEPRO 0.1%, the
elimination half-life of azelastine is 22 hours while that of
desmethylazelastine is 52 hours. Following intranasal administration of ASTEPRO
0.15%, the elimination half-life of azelastine is 25 hours while that of
desmethylazelastine is 57 hours. Approximately 75% of an oral dose of
radiolabeled azelastine hydrochloride was excreted in the feces with less than
10% as unchanged azelastine.
Special Populations
Hepatic Impairment
Following oral administration, pharmacokinetic parameters
were not influenced by hepatic impairment.
Renal Impairment
Based on oral, single-dose studies, renal insufficiency
(creatinine clearance < 50 mL/min) resulted in a 70-75% higher Cmax and AUC
compared to healthy subjects. Time to maximum concentration was unchanged.
Age
Following oral administration, pharmacokinetic parameters
were not influenced by age.
Gender
Following oral administration, pharmacokinetic parameters
were not influenced by gender.
Race
The effect of race has not been evaluated.
Drug-Drug Interactions
Erythromycin
Co-administration of orally administered azelastine (4 mg
twice daily) with erythromycin (500 mg three times daily for 7 days) resulted
in Cmax of 5.36 ± 2.6 ng/mL and AUC of 49.7 ± 24 ng•h/mL for azelastine,
whereas, administration of azelastine alone resulted in Cmax of 5.57 ± 2.7
ng/mL and AUC of 48.4 ± 24 ng•h/mL for azelastine [see DRUG INTERACTIONS].
Cimetidine and Ranitidine
In a multiple-dose, steady-state drug interaction trial
in healthy subjects, cimetidine (400 mg twice daily) increased orally
administered mean azelastine (4 mg twice daily) concentrations by approximately
65%. Co-administration of orally administered azelastine (4 mg twice daily)
with ranitidine hydrochloride (150 mg twice daily) resulted in Cmax of 8.89
±3.28 ng/mL and AUC of 88.22 ± 40.43 ng•h/mL for azelastine, whereas,
administration of azelastine alone resulted in Cmax of 7.83 ± 4.06 ng/mL and
AUC of 80.09 ± 43.55 ng•h/mL for azelastine [see DRUG INTERACTIONS].
Theophylline
No significant pharmacokinetic interaction was observed
with the coadministration of an oral 4 mg dose of azelastine hydrochloride
twice daily and theophylline 300 mg or 400 mg twice daily.
Clinical Studies
Seasonal Allergic Rhinitis
ASTEPRO 0.1%
The efficacy and safety of ASTEPRO 0.1% was evaluated in
a 2-week, randomized, multicenter, double-blind, placebo-controlled clinical
trial including 834 adult and adolescent patients 12 years of age and older
with symptoms of seasonal allergic rhinitis. The population was 12 to 83 years
of age (60% female, 40% male; 69% white, 16% black, 12% Hispanic, 2% Asian, 1%
other).
Patients were randomized to one of six treatment groups:
1 spray per nostril of either ASTEPRO 0.1%, Astelin (azelastine hydrochloride)
Nasal Spray or vehicle placebo twice daily; or 2 sprays per nostril of ASTEPRO
0.1%, Astelin or vehicle placebo twice daily.
Assessment of efficacy was based on the 12-hour
reflective total nasal symptom score (rTNSS) assessed daily in the morning and
evening, in addition to the instantaneous total nasal symptom score (iTNSS) and
other supportive secondary efficacy variables. TNSS is calculated as the sum of
the patients' scoring of the four individual nasal symptoms (rhinorrhea, nasal
congestion, sneezing, and nasal itching) on a 0 to 3 categorical severity scale
(0 = absent, 1 = mild, 2 = moderate, 3 = severe). The rTNSS required patients
to record symptom severity over the previous 12 hours. For the primary efficacy
endpoint, the mean change from baseline rTNSS, morning (AM) and evening (PM)
rTNSS scores were summed for each day (maximum score of 24) and then averaged
over the 2 weeks. The iTNSS, recorded immediately prior to the next dose, were
assessed as an indication of whether the effect was maintained over the dosing
interval.
In this trial, ASTEPRO 0.1% two sprays twice a day
demonstrated a greater decrease in rTNSS and iTNSS than placebo and the
difference was statistically significant. The trial results are presented in
Table 4 (Trial 1).
The efficacy of ASTEPRO 0.1% one spray per nostril twice
daily for seasonal allergic rhinitis is supported by two, 2-week,
placebo-controlled clinical trials with Astelin (azelastine hydrochloride) Nasal
Spray in 413 patients with seasonal allergic rhinitis. In these trials,
efficacy was assessed using the TNSS (described above). Astelin demonstrated a
greater decrease from baseline in the summed AM and PM rTNSS compared with
placebo and the difference was statistically significant.
The efficacy of ASTEPRO 0.1% and ASTEPRO 0.15% in
children 6 months to 5 years of age with allergic rhinitis was explored in a 4
week, randomized, open-label safety trial in 191 patients. While the primary
objective was to determine the safety of ASTEPRO in this age group, the study
included an exploratory efficacy assessment of daily overall allergy symptom
scores. Efficacy in children 6 months to 5 years of age was supported by a
numerical decrease in the overall allergy symptom score in both treatment
groups. There was no statistically significant difference between the two
treatment groups.
ASTEPRO 0.1 5%
The efficacy and safety of ASTEPRO 0.15% in seasonal
allergic rhinitis was evaluated in five randomized, multicenter, double-blind,
placebo-controlled clinical trials in 2499 adult and adolescent patients 12
years and older with symptoms of seasonal allergic rhinitis (Trials 2, 3, 4, 5,
and 6). The population of the trials was 12 to 83 years of age (64% female, 36%
male; 81% white, 12% black, < 2% Asian, 5% other; 23% Hispanic, 77%
non-Hispanic). Assessment of efficacy was based on the rTNSS, iTNSS as
described above, and other supportive secondary efficacy variables. The primary
efficacy endpoint was the mean change from baseline in rTNSS over 2 weeks.
Two 2-week seasonal allergic rhinitis trials evaluated
the efficacy of ASTEPRO Nasal Spray 0.15% dosed at 2 sprays twice daily. The
first trial (Trial 2) compared the efficacy of ASTEPRO 0.15% and Astelin
(azelastine hydrochloride) Nasal Spray to vehicle placebo. The other trial
(Trial 3) compared the efficacy of ASTEPRO 0.15% and ASTEPRO 0.1% to vehicle
placebo. In these two trials, ASTEPRO 0.15% demonstrated greater decreases in
rTNSS than placebo and the differences were statistically significant (Table
4).
Three 2-week seasonal allergic rhinitis trials evaluated
the efficacy of ASTEPRO 0.15% dosed at 2 sprays once daily compared to the
vehicle placebo. Trial 4 demonstrated a greater decrease in rTNSS than placebo
and the difference was statistically significant (Table 4). Trial 5 and Trial 6
were conducted in patients with Texas mountain cedar allergy. In Trial 5 and
Trial 6, ASTEPRO 0.15% demonstrated a greater decrease in rTNSS than placebo
and the differences were statistically significant (Trials 5 and 6; Table 4).
Instantaneous TNSS results for the once daily dosing regimen of ASTEPRO 0.15%
are shown in Table 5. In Trials 5 and 6, ASTEPRO 0.15% demonstrated a greater
decrease in iTNSS than placebo and the differences were statistically
significant.
Table 4: Mean Change from Baseline in Reflective TNSS
over 2 Weeks* in Adults and Children ≥ 12 years with Seasonal Allergic
Rhinitis
|
Treatment (sprays per nostril) |
n |
Baseline LS Mean |
Change from Baseline |
Difference From Placebo |
LS Mean |
95% CI |
P value |
Trial 1 |
Two sprays twice daily |
ASTEPRO 0.1% |
146 |
18.0 |
-5.0 |
-2.2 |
.2 -1. < N -3. |
< 0.001 |
Astelin Nasal Spray |
137 |
18.2 |
-4.2 |
-1.4 |
-2.4,-0.4 |
0.01 |
Vehicle Placebo |
138 |
18.2 |
-2.8 |
|
One spray twice daily |
ASTEPRO 0.1% |
139 |
18.2 |
-4.2 |
-0.7 |
-1.7, 0.3 |
0.18 |
Astelin Nasal Spray |
137 |
18.1 |
-4.0 |
-0.4 |
-1.5, 0.6 |
0.41 |
Vehicle Placebo |
137 |
18.0 |
-3.5 |
|
Trial 2 |
Two sprays twice daily |
ASTEPRO 0.15% |
153 |
18.2 |
-4.3 |
-1.2 |
.3 -0. -2. |
0.01 |
Astelin Nasal Spray |
153 |
17.9 |
-3.9 |
-0.9 |
-1.8, 0.1 |
0.07 |
Vehicle Placebo |
153 |
18.1 |
-3.0 |
|
Trial 3 |
Two sprays twice daily |
ASTEPRO 0.15% |
177 |
17.7 |
-5.1 |
-3.0 |
.1 -2. G) -3. |
< 0.001 |
ASTEPRO 0.1% |
169 |
18.2 |
-4.2 |
-2.1 |
.2 -1. 0, -3. |
< 0.001 |
Vehicle Placebo |
177 |
17.7 |
-2.1 |
|
Trial 4 |
Two sprays once daily |
ASTEPRO 0.15% |
238 |
17.4 |
-3.4 |
-1.0 |
.3 -0. rC 1. |
0.008 |
Vehicle Placebo |
242 |
17.4 |
-2.4 |
|
Trial 5 |
Two sprays once daily |
ASTEPRO 0.15% |
266 |
18.5 |
-3.3 |
-1.4 |
.8 -0. -2. |
< 0.001 |
Vehicle Placebo |
266 |
18.0 |
-1.9 |
|
Trial 6 |
Two sprays once daily |
ASTEPRO 0.15% |
251 |
18.5 |
-3.4 |
-1.4 |
-2.1, -0.7 |
< 0.001 |
Vehicle Placebo |
254 |
18.8 |
-2.0 |
|
*Sum of AM and PM rTNSS for
each day (Maximum score=24) and averaged over the 14 day treatment period |
Table 5: Mean Change from
Baseline AM Instantaneous TNSS over 2 Weeks* in Adults and Children ≥ 12 years with Seasonal Allergic Rhinitis
|
Treatment (sprays per nostril once daily) |
n |
Baseline LS Mean |
Change from Baseline |
Difference From Placebo |
LS Mean |
95% CI |
P value |
Trial 4 |
Two sprays once daily |
ASTEPRO 0.15% |
238 |
8.1 |
-1.3 |
-0.2 |
-0.6, 0.1 |
0.15 |
Vehicle Placebo |
242 |
8.3 |
-1.1 |
|
Trial 5 |
Two sprays once daily |
ASTEPRO 0.15% |
266 |
8.7 |
-1.4 |
-0.7 |
.4 -0. O. 1. |
< 0.001 |
Vehicle Placebo |
266 |
8.3 |
-0.7 |
|
Trial 6 |
Two sprays once daily |
ASTEPRO 0.15% |
251 |
8.9 |
-1.4 |
-0.6 |
.3 -0. -0. |
< 0.001 |
Vehicle Placebo |
254 |
8.9 |
-0.8 |
|
*AM iTNSS for each day (Maximum
score=12) and averaged over the 14 day treatment period |
ASTEPRO 0.15% at a dose of 1
spray twice daily was not studied. The ASTEPRO 0.15% 1 spray twice daily dosing
regimen is supported by previous findings of efficacy for Astelin (azelastine
hydrochloride) Nasal Spray and a favorable comparison of ASTEPRO 0.15% to
Astelin Nasal Spray and ASTEPRO 0.1% (Table 4).
The efficacy and safety of
ASTEPRO 0.1% and 0.15% in children 6 to 11 years of age with seasonal allergic
rhinitis was evaluated in a clinical study that enrolled pediatric patients
with perennial allergic rhinitis, with or without concomitant seasonal allergic
rhinitis (described below in Section 14.2).
Perennial Allergic Rhinitis
ASTEPRO 0.1% and ASTEPRO 0.15%
The efficacy and safety of
ASTEPRO 0.15% in perennial allergic rhinitis was evaluated in one randomized,
multicenter, double-blind, placebo-controlled clinical trial in 578 adult and adolescent
patients 12 years and older with symptoms of perennial allergic rhinitis. The
population of the trial was 12 to 84 years of age (68% female, 32% male; 85%
white, 11% black, 1% Asian, 3% other; 17% Hispanic, 83% non-Hispanic).
Assessment of efficacy was based on the 12-hour
reflective total nasal symptom score (rTNSS) assessed daily in the morning and
evening, the instantaneous total nasal symptom score (iTNSS), and other
supportive secondary efficacy variables. The primary efficacy endpoint was the
mean change from baseline rTNSS over 4 weeks. The one 4-week perennial allergic
rhinitis trial evaluated the efficacy of ASTEPRO 0.15%, ASTEPRO 0.1%, and
vehicle placebo dosed at 2 sprays per nostril twice daily. In this trial,
ASTEPRO 0.15% demonstrated a greater decrease in rTNSS than placebo and the
difference was statistically significant (Table 6).
Table 6: Mean Change from Baseline in Reflective TNSS
over 4 Weeks* in Adults and Children ≥ 12 years with Perennial
Allergic Rhinitis
|
Treatment (sprays per nostril twice daily) |
n |
Baseline LS Mean |
Change from Baseline |
Difference From Placebo |
LS Mean |
95% CI |
P value |
Two sprays twice daily |
ASTEPRO 0.15% |
192 |
15.8 |
-4.0 |
-0.9 |
-1.7, -0.1 |
0.03 |
ASTEPRO 0.1% |
194 |
15.5 |
-3.8 |
-0.7 |
-1.5, 0.1 |
0.08 |
Vehicle Placebo |
192 |
14.7 |
-3.1 |
|
*Sum of AM and PM rTNSS for
each day (Maximum score=24) and averaged over the 28 day treatment period |
The efficacy and safety of
ASTEPRO 0.1% and ASTEPRO 0.15% in pediatric patients 6 to 11 years of age with
perennial allergic rhinitis, with or without concomitant seasonal allergic
rhinitis, was evaluated in a randomized, double-blind, placebo-controlled
clinical trial in 486 patients. All patients received one spray per nostril
twice daily. The study population was 58% males and 42% females; 78% white, 13%
black, 3% Asian, and 6% other.
Assessment of efficacy was
based on the 12-hour reflective total nasal symptom score (rTNSS) assessed
daily in the morning and evening. The primary efficacy endpoint was the mean change
from baseline rTNSS over 4 weeks (Table 7). Both active treatments demonstrated
statistically significant decreases in rTNSS compared to placebo. There was no
statistically significant difference between the two active-treatment groups.
There was also no difference in treatment effect between patients with
perennial allergic rhinitis only compared to those with perennial allergic
rhinitis and concomitant seasonal allergic rhinitis.
Table 7: Mean Change from
Baseline in Reflective TNSS over 4 Weeks* in Children 6 to 11 years with
Perennial Allergic Rhinitis
|
Treatment (sprays per nostril twice daily) |
n |
Baseline LS Mean |
Change from Baseline |
Difference From Placebo |
LS Mean |
95% CI |
P value |
One spray twice daily |
ASTEPRO 0.15% |
159 |
16.6 |
-3.5 |
-1.0 |
-1.7, -0.3 |
0.005 |
ASTEPRO 0.1% |
166 |
16.4 |
-3.4 |
-0.9 |
.2 -0. 1. |
0.015 |
Vehicle Placebo |
161 |
16.1 |
-2.5 |
|
*Sum of AM and PM rTNSS for
each day (Maximum score=24) and averaged over the 28 day treatment period |
The efficacy of ASTEPRO 0.1%
and ASTEPRO 0.15% in children 6 months to 5 years of age with allergic rhinitis
was explored in a clinical study (described above in Section 14.1).