5.1 Worsening of Urinary Retention

Qbrexza should be used with caution in patients with a history or presence of documented urinary retention. Prescribers and patients should be alert for signs and symptoms of urinary retention (e.g., difficulty passing urine, distended bladder), especially in patients with prostatic hypertrophy or bladder-neck obstruction. Instruct patients to discontinue use immediately and consult a physician should any of these signs or symptoms develop.

Patients with a history of urinary retention were not included in the clinical studies.

5.2 Control of Body Temperature

In the presence of high ambient temperature, heat illness (hyperpyrexia and heat stroke due to decreased sweating) can occur with the use of anticholinergic drugs such as Qbrexza. Advise patients using Qbrexza to watch for generalized lack of sweating when in hot or very warm environmental temperatures and to avoid use if not sweating under these conditions.

5.3 Operating Machinery or an Automobile

Transient blurred vision may occur with use of Qbrexza. If blurred vision occurs, the patient should discontinue use until symptoms resolve. Patients should be warned not to engage in activities that require clear vision such as operating a motor vehicle or other machinery, or performing hazardous work until the symptoms have resolved.

6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

In two double-blind, vehicle-controlled clinical trials (Trial 1 [NCT02530281] and Trial 2 [NCT02530294]) of 459 subjects treated with Qbrexza once daily and 232 treated with vehicle, subjects were 9 to 76 years of age, 47% male, and the percentages of White, Black (including African Americans), and Asian subjects were 82%, 12%, and 1%, respectively.

Table 1 summarizes the most frequent adverse reactions (≥2%) in subjects with primary axillary hyperhidrosis treated with Qbrexza.

Table 2 shows the most frequently reported local skin reactions, which were relatively common in both the Qbrexza and vehicle groups.

In an open-label safety trial (NCT02553798), 564 subjects were treated for up to an additional 44 weeks after completing Trial 1 or Trial 2. Adverse reactions occurring at a frequency ≥2.0% were: dry mouth (16.9%), vision blurred (6.7%), nasopharyngitis (5.8%), mydriasis (5.3%), urinary hesitation (4.2%), nasal dryness (3.6%), dry eye (2.9%), pharyngitis (2.2%), and application site reactions (pain [6.4%], dermatitis [3.8%], pruritus [3.8%], rash [3.8%], erythema [2.4%]).

7.1 Anticholinergics

Coadministration of Qbrexza with anticholinergic medications may result in additive interaction leading to an increase in anticholinergic adverse effects [see Warnings and Precautions (5) and Adverse Reactions (6)]. Avoid coadministration of Qbrexza with other anticholinergic-containing drugs.

8.1 Pregnancy

Risk Summary

There are no available data on Qbrexza use in pregnant women to inform a drug-associated risk for adverse developmental outcomes. In pregnant rats, daily oral administration of glycopyrrolate (glycopyrronium bromide) during organogenesis did not result in an increased incidence of gross external or visceral defects [see Data]. When glycopyrrolate was administered intravenously to pregnant rabbits during organogenesis, no adverse effects on embryo-fetal development were seen. The available data do not support relevant comparisons of systemic glycopyrronium exposures achieved in the animal studies to exposures observed in humans after topical use of Qbrexza.

The estimated background risks of major birth defects and miscarriage for the indicated population are unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

Data

Animal Data

Glycopyrrolate was orally administered to pregnant rats at dosages of 50, 200, and 400 mg/kg/day during the period of organogenesis. Glycopyrrolate had no effect on maternal survival, but significantly reduced mean maternal body weight gain over the period of dosing at all dosages evaluated. Mean fetal weight was significantly reduced in the 200 and 400 mg/kg/day dose groups. There were two litters with all resorbed fetuses in the 400 mg/kg/day dose group. There were no effects of treatment on the incidence of gross external or visceral defects. Minor treatment-related skeletal effects included reduced ossification of various bones in the 200 and 400 mg/kg/day dose groups; these skeletal effects were likely secondary to maternal toxicity.

Glycopyrrolate was intravenously administered to pregnant rabbits at dosages of 0.1, 0.5, and 1.0 mg/kg/day during the period of organogenesis. Glycopyrrolate did not affect maternal survival under the conditions of this study. Mean maternal body weight gain and mean food consumption over the period of dosing were lower than the corresponding control value in the 0.5 and 1.0 mg/kg/day treatment groups. There were no effects of treatment on fetal parameters, including fetal survival, mean fetal weight, and the incidence of external, visceral, or skeletal defects.

Female rats that were pregnant or nursing were orally dosed with glycopyrrolate daily at dosages of 0, 50, 200, or 400 mg/kg/day, beginning on day 7 of gestation, and continuing until day 20 of lactation. Mean body weight of pups in all treatment groups was reduced compared to the control group during the period of nursing, but eventually recovered to be comparable to the control group, post-weaning. No other notable delivery or litter parameters were affected by treatment in any group, including no effects on mean duration of gestation or mean numbers of live pups per litter. No treatment-related effects on survival or adverse clinical signs were observed in pups. There were no effects of maternal treatment on behavior, learning, memory, or reproductive function of pups.

8.2 Lactation

Risk Summary

There are no data on the presence of glycopyrrolate or its metabolites in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Qbrexza and any potential adverse effects on the breastfed infant from Qbrexza or from the underlying maternal condition.

8.4 Pediatric Use

The safety, effectiveness and pharmacokinetics of Qbrexza have been established in pediatric patients age 9 years and older for topical treatment of primary axillary hyperhidrosis [see Clinical Pharmacology (12.3)]. Use of Qbrexza in this age group is supported by evidence from two multicenter, randomized, double-blind, parallel-group, vehicle-controlled 4-week trials which included 34 pediatric subjects 9 years and older [see Adverse Reactions (6.1) and Clinical Studies (14)]. The safety and effectiveness of Qbrexza have not been established in pediatric patients under 9 years of age.

8.5 Geriatric Use

Clinical trials of Qbrexza did not include sufficient numbers of subjects age 65 years and older to determine whether they respond differently from younger subjects.

8.6 Renal Impairment

The elimination of glycopyrronium is severely impaired in patients with renal failure [see Clinical Pharmacology (12.3)].

12.1 Mechanism of Action

Glycopyrronium is a competitive inhibitor of acetylcholine receptors that are located on certain peripheral tissues, including sweat glands. In hyperhidrosis, glycopyrronium inhibits the action of acetylcholine on sweat glands, reducing sweating.

12.2 Pharmacodynamics

The pharmacodynamics of Qbrexza are not known.

12.3 Pharmacokinetics

Absorption

The pharmacokinetics of glycopyrronium were evaluated in adult and pediatric patients with primary axillary hyperhidrosis following Qbrexza once daily applied to the axillae for 5 days. The mean ± SD exposures of glycopyrronium are presented in Tables 3 and 4. There was no evidence of accumulation.

Distribution

After IV administration, glycopyrronium has a mean volume of distribution in children aged 1 to 14 years of approximately 1.3 to 1.8 L/kg, with a range from 0.7 to 3.9 L/kg. In adults aged 60-75 years, the volume of distribution was lower (0.42 L/kg ± 0.22).

Elimination

Metabolism

A small proportion of glycopyrronium is metabolized following IV administration. The metabolic pathway for glycopyrronium is not characterized.

Excretion

Following administration of a single radiolabeled IV glycopyrronium dose to adult subjects who underwent surgery for cholelithiasis, approximately 85% of total radioactivity was excreted in urine and < 5% was present in bile drainage. Greater than 80% of the radioactivity in both urine and bile was unchanged drug.

Specific Populations

The pharmacokinetics of glycopyrronium were not evaluated in pregnant women or patients with hepatic impairment.

Pediatric Subjects

The mean ± SD exposures of glycopyrronium in pediatric subjects following Qbrexza once daily for 5 days are presented in Table 4. There was no evidence of accumulation.

Patients with Renal Impairment

Following a 4 mcg/kg IV dose of a glycopyrronium formulation for IV use, mean glycopyrronium AUC (10.6 mcg·h/L), CL (0.43 L/h/kg) and 3-hour urinary excretion (0.7%) were significantly different in uremic subjects undergoing renal transplantation surgery than those of healthy subjects (3.73 mcg·h/L, 1.14 L/h/kg, and 50%, respectively).

Pharmacokinetics of Qbrexza in subjects with renal impairment has not been studied.

In Vitro Studies

In vitro studies indicated that under the conditions of clinical use, Qbrexza is not expected to induce cytochrome P450 (CYP) enzymes 1A2, 2B6 and 3A4; or inhibit 1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

Glycopyrronium tosylate was not carcinogenic when topically applied to rats daily for up to 24 months in solution at concentrations of 1%, 2%, and 4% w/w.

When glycopyrrolate was administered via oral gavage to mice for up to 24 months at dosages of 2.5, 7, and 20 mg/kg/day in both genders, no significant changes in tumor incidence were observed when compared to control.

When glycopyrrolate was administered via oral gavage to rats for up to 24 months at dosages of 5, 15, and 40 mg/kg/day in both genders, no significant changes in tumor incidence were observed when compared to control.

Glycopyrrolate was negative in a battery of genetic toxicology studies that included a bacterial reverse mutation (Ames) assay, a mouse lymphoma assay conducted with L5178Y/TK+/- cells, and an in vivo micronucleus assay with mice. Glycopyrronium tosylate was negative in an Ames assay.

Glycopyrrolate was assessed for effects on fertility or general reproductive function in rats. Rats of both genders received glycopyrrolate at dosages up to 100 mg/kg/day via oral gavage. No treatment-related effects on fertility or reproductive parameters were observed in either gender.

14.1 Efficacy and Safety Trials

Two randomized, vehicle-controlled multicenter trials, Trial 1 (NCT02530281) and Trial 2 (NCT02530294), were conducted in subjects with primary axillary hyperhidrosis and enrolled a total of 697 subjects 9 years of age or older. Inclusion criteria required that prior to the start of treatment, all subjects produce at least 50 mg of sweat in each axilla over a 5-minute period and rate the severity of their sweating daily over a week with a mean score of 4 or higher on the ASDD item #2, a patient reported outcome instrument scored from 0 (no sweating) to 10 (worst possible sweating). The median sweat production over 5 minutes at baseline was 122 mg in the Qbrexza arm and 113 mg in the vehicle arm in Trial 1, and 127 mg in the Qbrexza arm and 117 mg in the vehicle arm in Trial 2. The average weekly mean score on the ASDD item #2 at baseline was approximately 7.2 across both trials.

Subjects were randomized to receive either Qbrexza or vehicle applied once daily to each axilla. The co-primary endpoints were the proportion of subjects having at least a 4-point improvement from baseline in the weekly mean ASDD item #2 score at Week 4 and the mean absolute change from baseline in gravimetrically measured sweat production at Week 4.

Clinical Response

The results of Trial 1 and Trial 2 are presented in Table 5 below.

16.1 How Supplied

Qbrexza is supplied as:

A single-use cloth pre-moistened with a 2.4% glycopyrronium solution in a pouch

Carton of 30 pouches      NDC 70428-011-12

16.2 Storage and Handling

Store at room temperature 20° - 25°C (68° - 77°F); excursions permitted to 15° - 30°C (59° - 86°F) [See USP Controlled Room Temperature].

Qbrexza is flammable; keep away from heat or flame.