Clinical Pharmacology for Patanase Nasal Spray
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 Electrophysiology
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 12-month study in 429 perennial allergic rhinitis patients treated with PATANASE two 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. 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 was about 1.3.
Seasonal Allergic Rhinitis Patients
Systemic exposure of olopatadine in SAR patients after twice daily intranasal administration of PATANASE 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.
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.
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.
Specific Populations
Patients With 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 is warranted in patients with hepatic impairment.
Patients With Renal Impairment
The mean Cmax values for olopatadine following single nasal 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). The mean plasma AUC0-12 was 2-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 welltolerated. These findings indicate that no adjustment of the dosing regimen of PATANASE is warranted in patients with renal impairment.
Male And Female Patients
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.
Racial Or Ethnic Groups
The effects of race on olopatadine pharmacokinetics have not been adequately investigated.
Pediatric Patients 6 To 11 Years Of Age
The systemic pharmacokinetics of olopatadine, olopatadine N-oxide and N-desmethyl olopatadine in patients 6 through 11 years of age were characterized using data from 42 pediatric patients administered PATANASE, 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 Ndesmethyl 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 (one spray per nostril) of PATANASE 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·h/mL respectively. The mean Cmax and AUC0-12 of olopatadine N-oxide and N-desmethyl 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.
Clinical Studies
Adult And Adolescent Patients 12 Years Of Age And Older
The efficacy and safety of PATANASE were evaluated in 3 randomized, double blind, parallel group, multicenter, placebo-controlled clinical trials (vehicle nasal spray) of 2 weeks duration in adult and adolescent patients, 12 years of age and older with symptoms of seasonal allergic rhinitis. The 3 clinical trials were conducted in the United States and included 1598 patients (556 males, and 1042 females) 12 years of age and older. In these 3 trials, 587 patients were treated with PATANASE 0.6%, 418 patients were treated with PATANASE 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, two sprays per nostril, twice-daily, exhibited statistically significantly greater decreases in rTNSS compared to vehicle nasal spray. Results for the rTNSS from 2 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
| Study No. |
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 |
8.90 |
-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 |
-2.90 |
-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 |
|
|
|
| Abbreviation: CI, confidence interval. |
Itchy eyes and watery eyes were evaluated as secondary endpoints but eye redness was not evaluated. In 2 of the studies, patients treated with PATANASE 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 3 environmental exposure unit studies with single doses of PATANASE. In these studies, patients with SAR were exposed to high levels of pollen in the environmental exposure unit and then treated with either PATANASE 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 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 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 1188 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, one or two 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 in Pediatric Patients 6 to 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%, one spray per nostril twice daily |
294 |
8.99 |
-2.24 |
-0.55 |
(-0.90, -0.19) |
0.0015 |
| Vehicle Nasal Spray, one spray per nostril twice daily |
294 |
9.09 |
-1.70 |
|
|
|
| Abbreviation: CI, confidence interval. |
Itchy eyes and watery eyes were evaluated as secondary endpoints in the same study but eye redness was not evaluated. Patients treated with PATANASE had significantly greater decreases in reflective symptom scores for itchy eyes and watery eyes, compared to vehicle nasal spray.