CLINICAL PHARMACOLOGY
Mechanism of Action
Olopatadine is a histamine H1 -receptor antagonist. The
antihistaminic activity of olopatadine has been documented in isolated tissues,
animal models, and humans.
Pharmacodynamics
Cardiac effects
In a placebo-controlled cardiovascular safety study, 32
healthy volunteers received 20 mg oral solution of olopatadine twice daily for
14 days (8-fold greater daily dose than the recommended daily nasal dose). The
mean QTcF (QT corrected by Fridericia's correction method for heart rate)
change from baseline was -2.7 msec and -3.8 msec for olopatadine, and placebo,
respectively. In this study, 8 subjects treated with olopatadine had a QTcF
change from baseline of 30 – 60 msec, 1 subject had a QTcF change from baseline
greater than 60 msec, and no subjects had QTcF values greater than 500 msec.
Eight subjects treated with placebo had a QTcF change from baseline of 30 – 60
msec, no subjects had a QTcF change from baseline greater than 60 msec, and no
subjects had QTcF values greater than 500 msec. In a 12month study in 429
perennial allergic rhinitis patients treated with PATANASE Nasal Spray 2 sprays
per nostril twice daily, no evidence of any effect of olopatadine hydrochloride
on QT prolongation was observed.
Pharmacokinetics
The pharmacokinetic properties of olopatadine were studied
after administration by the nasal, oral, intravenous, and topical ocular
routes. Olopatadine exhibited linear pharmacokinetics across the routes studied
over a large dose range.
Absorption
Healthy Subjects: Olopatadine was absorbed with
individual peak plasma concentrations observed between 30 minutes and 1 hour
after twice daily intranasal administration of PATANASE Nasal Spray. The mean (
± SD) steady-state peak plasma concentration (Cmax) of olopatadine was 16.0 ± 8.99
ng/mL. Systemic exposure as indexed by area under the curve (AUC0-12) averaged
66.0 ± 26.8 ng·h/mL. The average absolute bioavailability of intranasal
olopatadine is 57%. The mean accumulation ratio following multiple intranasal
administration of PATANASE Nasal Spray was about 1.3.
Seasonal Allergic Rhinitis (SAR) Patients: Systemic
exposure of olopatadine in SAR patients after twice daily intranasal
administration of PATANASE Nasal Spray was comparable to that observed in
healthy subjects. Olopatadine was absorbed with peak plasma concentrations
observed between 15 minutes and 2 hours. The mean steady-state Cmax was 23.3 ± 6.2
ng/mL and AUC0-12 averaged 78.0 ± 13.9 ng•h/mL.
Distribution
The protein binding of olopatadine was moderate at
approximately 55% in human serum, and independent of drug concentration over
the range of 0.1 to 1000 ng/mL. Olopatadine was bound predominately to human
serum albumin.
Metabolism
Olopatadine is not extensively metabolized. Based on plasma
metabolite profiles following oral administration of [14C]
olopatadine, at least six minor metabolites circulate in human plasma.
Olopatadine accounts for 77% of peak plasma total radioactivity and all
metabolites amounted to < 6% combined. Two of these have been identified as
the olopatadine N-oxide and N-desmethyl olopatadine. In in vitro studies with
cDNA-expressed human cytochrome P450 isoenzymes (CYP) and flavin-containing
monooxygenases (FMO), N-desmethyl olopatadine (Ml) formation was catalyzed
mainly by CYP3A4, while olopatadine N-oxide (M3) was primarily catalyzed by
FMO1 and FMO3. Olopatadine at concentrations up to 33,900 ng/mL did not inhibit
the in vitro metabolism of specific substrates for CYP1A2, CYP2C9, CYP2C19,
CYP2D6, CYP2E1 and CYP3A4. The potential for olopatadine and its metabolites to
act as inducers of CYP enzymes has not been evaluated.
Elimination
The plasma elimination half-life of olopatadine is 8 to 12
hours. Olopatadine is mainly eliminated through urinary excretion.
Approximately 70% of a [14C] olopatadine hydrochloride oral dose was
recovered in urine with 17% in the feces. Of the drug-related material
recovered within the first 24 hours in the urine, 86% was unchanged olopatadine
with the balance comprised of olopatadine N-oxide and N-desmethyl olopatadine.
Special Population
Hepatic Impairment: No specific pharmacokinetic study
examining the effect of hepatic impairment was conducted. Since metabolism of
olopatadine is a minor route of elimination, no adjustment of the dosing
regimen of PATANASE Nasal Spray is warranted in patients with hepatic
impairment.
Renal Impairment: The mean Cmax values for
olopatadine following single intranasal doses were not markedly different
between healthy subjects (18.1 ng/mL) and patients with mild, moderate and
severe renal impairment (range 15.5 to 21.6 ng/mL). Mean plasma AUC0-12 was
two-fold higher in patients with severe impairment (creatinine clearance < 30
mL/min/1.73 m²). In these patients, peak steady-state plasma concentrations of
olopatadine are approximately 10-fold lower than those observed after higher 20
mg oral doses, twice daily, which were well-tolerated. These findings indicate
that no adjustment of the dosing regimen of PATANASE Nasal Spray is warranted
in patients with renal impairment.
Gender: The mean systemic exposure (Cmax and AUC0-12)
in female SAR patients following multiple administration of olopatadine was 40%
and 27% higher, respectively than those values observed in male SAR patients.
Race: The effects of race on olopatadine
pharmacokinetics have not been adequately investigated.
Age: Pediatric Patients 6 to 11 Years of Age:
The systemic pharmacokinetics of olopatadine, olopatadine N-oxide and
Ndesmethyl olopatadine in patients 6 through 11 years of age were characterized
using data from 42 pediatric patients administered PATANASE Nasal Spray, one
spray per nostril twice daily for a minimum of 14 days. The mean Cmax (15.4 ±
7.3 ng/mL) of olopatadine was approximately 2-fold less than was comparable to
that observed in adults (78.0 ± 13.9 ng·h/mL). The Cmax and AUC0-12 of
olopatadine N-oxide were comparable to that observed in adults. The Cmax and
AUC0-12 of N-desmethyl olopatadine are approximately 18% and 37% higher than
that observed in adults, respectively.
Pediatric Patients 2 to 5 Years of Age: The systemic
pharmacokinetics of olopatadine, olopatadine N-oxide, and N-desmethyl
olopatadine were characterized using population pharmacokinetic methods applied
to sparse data (approximately 5 samples per patient) obtained from 66 pediatric
patients (2 to less than 6 years of age) administered one-half the recommended
adult dose (1 spray per nostril) of PATANASE Nasal Spray twice daily for a
minimum of 14 days. The mean Cmax and AUC0-12 of olopatadine were 13.4 ± 4.6
ng/mL and 75.0± 26.4 ng*hr/mL respectively. The mean Cmax and AUC0-12 of
olopatdine N-oxide and Ndesmethyl olopatadine were similar to that of patients
6 to 11 years of age.
Drug Interaction Studies
Drug interactions with inhibitors of liver enzymes are not
anticipated because olopatadine is eliminated predominantly by renal excretion.
Olopatadine did not inhibit the in vitro metabolism of specific substrates for
CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4. Based on these data, drug
interactions involving P450 inhibition are not expected. Due to the modest
protein binding of olopatadine (55%), drug interactions through displacement
from plasma proteins are also not expected.
Animal Toxicology
Reproductive Toxicology Studies
Olopatadine was not teratogenic in rabbits and rats at oral
doses of up to 400 or 600 mg/kg/day, respectively (approximately 1,400 and
1,000 times the MRHD for adults on a mg/m² basis, respectively). However, a
decrease in the number of live fetuses was observed in rabbits at the oral
olopatadine doses of 25 mg/kg (approximately 88 times the MRHD for adults on a
mg/m² basis) and above, and in rats at oral doses of 60 mg/kg (approximately
100 times the MRHD for adults on a mg/m² basis) and above. In rats, viability
and body weights of pups were reduced on day 4 post partum at the oral doses of
60 mg/kg (approximately 100 times the MRHD for adults on a mg/m² basis) and
above, but no effect on viability was observed at the dose of 20 mg/kg
(approximately 35 times the MRHD for adults on a mg/m² basis).
Clinical Studies
Adult and Adolescent Patients 12 Years of Age and Older
The efficacy and safety of PATANASE Nasal Spray were
evaluated in three randomized, double blind, parallel group, multicenter,
placebo (vehicle nasal spray)-controlled clinical trials of 2 weeks duration in
adult and adolescent patients, 12 years of age and older with symptoms of
seasonal allergic rhinitis. The three clinical trials were conducted in the
United States and included 1,598 patients (556 males, and 1,042 females) 12
years of age and older. In these three trials 587 patients were treated with
PATANASE Nasal Spray 0.6%, 418 patients were treated with PATANASE Nasal Spray
0.4%, and 593 patients were treated with vehicle nasal spray. Assessment of
efficacy was based on patient recording of 4 individual nasal symptoms (nasal congestion,
rhinorrhea, itchy nose, and sneezing) on a 0 to 3 categorical severity scale (0
= absent, 1 = mild, 2 = moderate, 3 = severe) as reflective or instantaneous
scores. Reflective scoring required patients to record symptom severity over
the previous 12 hours; the instantaneous scoring required patients to record
symptom severity at the time of recording. The primary efficacy endpoint was
the difference from placebo in the percent change from baseline in the average
of morning and evening reflective total nasal symptom score (rTNSS) averaged
for the 2-week treatment period. In all 3 trials, patients treated with
PATANASE Nasal Spray, two sprays per nostril, twice-daily, exhibited
statistically significantly greater decreases in rTNSS compared to vehicle
nasal spray. Results for the rTNSS from two representative trials are shown in
Table 3.
Table 3: Mean Reflective Total Nasal Symptom Score
(rTNSS) in Adult and Adolescent Patients with Seasonal Allergic Rhinitis
|
Treatment |
N |
Baseline |
Change from Baseline |
Difference from Placebo |
Estimate |
95% CI |
p-value |
Study 1 |
PATANASE Nasal Spray 0.6% |
183 |
8.71 |
-3.63 |
-0.96 |
(-1.42, -0.51) |
< 0.0001 |
PATANASE Nasal Spray 0.4% |
188 |
8.9 |
-3.38 |
-0.71 |
(-1.17, -0.26) |
0.0023 |
Vehicle Nasal Spray |
191 |
8.75 |
-2.67 |
|
|
|
Study 2 |
PATANASE Nasal Spray 0.6% |
220 |
9.17 |
-2.9 |
-0.98 |
(-1.37, -0.59) |
< 0.0001 |
PATANASE Nasal Spray 0.4% |
228 |
9.26 |
-2.63 |
-0.72 |
(-1.11, -0.33) |
0.0003 |
Vehicle Nasal Spray |
223 |
9.07 |
-1.92 |
|
|
|
Itchy eyes and watery eyes were evaluated as secondary
endpoints but eye redness was not evaluated. In two
of the studies, Patients treated with PATANASE Nasal Spray had significantly
greater decreases in reflective symptom scores for itchy eyes and watery eyes,
compared to vehicle nasal spray.
In the 2-week seasonal allergy
trials, onset of action was also evaluated by instantaneous TNSS assessments
twice-daily after the first dose of study medication. In these trials, onset of
action was seen after 1 day of dosing. Onset of action was evaluated in three
environmental exposure unit studies with single doses of PATANASE Nasal Spray.
In these studies, patients with seasonal allergic rhinitis were exposed to high
levels of pollen in the environmental exposure unit and then treated with
either PATANASE Nasal Spray or vehicle nasal spray, two sprays in each nostril,
after which they self-reported their allergy symptoms hourly as instantaneous
scores for the subsequent 12 hours. PATANASE Nasal Spray 0.6% was found to have
an onset of action of 30 minutes after dosing in the environmental exposure
unit.
Pediatric Patients 6 to 11 Years
of Age
There were 3 clinical trials of 2
weeks duration with olopatadine nasal spray in patients 6 to 11 years of age
with seasonal allergic rhinitis. Efficacy of Patanase Nasal Spray was evaluated
in 2 of the 3 trials. One of the 2 trials that showed efficacy was a
randomized, double blind, parallel group, multicenter, placebo (vehicle nasal
spray)-controlled clinical trial of 2 weeks duration including 1,188 children
ages 6 to < 12 years with seasonal allergic rhinitis. Assessment of efficacy
was based on patient/caregiver recording of 4 individual nasal symptoms (nasal
congestion, rhinorrhea, itchy nose, and sneezing) on a 0 to 3 categorical
severity scale (0 = absent, 1 = mild, 2 = moderate, 3 = severe) as reflective
or instantaneous scores. Reflective scoring captured symptom severity over the
previous 12 hours; the instantaneous scoring captured symptom severity at the
time of recording. The primary efficacy endpoint was the difference from
placebo in the percent change from baseline in the average of
patient/caregiver-reported morning and evening reflective total nasal symptom
score (rTNSS) averaged for the 2-week treatment period. Patients treated with
PATANASE Nasal Spray, 1 or 2 sprays per nostril twice daily, had statistically
significantly greater decreases in rTNSS compared to vehicle nasal spray.
Results for rTNSS are shown in Table 4.
Table 4: Mean Reflective Total
Nasal Symptom Score (rTNSS) in Pediatric Patients 6-11 Years of Age with
Seasonal Allergic Rhinitis
Treatment |
N |
Baseline |
Change from Baseline |
Difference from Placebo |
Estimate |
95% CI |
p-value |
PATANASE Nasal Spray 0.6%, 1 spray per nostril twice daily |
294 |
8.99 |
-2.24 |
-0.55 |
(-0.90, -0.19) |
0.0015 |
Vehicle Nasal Spray, 1 spray per nostril twice daily |
294 |
9.09 |
-1.7 |
|
|
|
Itchy eyes and watery eyes were
evaluated as secondary endpoints in the same study but eye redness was not
evaluated. Patients treated with PATANASE Nasal Spray had significantly greater
decreases in reflective symptom scores for itchy eyes and watery eyes, compared
to vehicle nasal spray.