AZOPT- brinzolamide_suspension/ drops

Carbonic anhydrase is an enzyme found in many tissues of the body, including the eye. It catalyzes the reversible reaction involving the hydration of carbon dioxide and the dehydration of carbonic acid. In humans, carbonic anhydrase exists as a number of isoenzymes, the most active being carbonic anhydrase II, found primarily in red blood cells (RBCs), but also in other tissues. Inhibition of carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport. The result is a reduction in IOP. AZOPT contains brinzolamide, an inhibitor of carbonic anhydrase II. Following topical ocular administration, brinzolamide inhibits aqueous humor formation and reduces elevated IOP. Elevated IOP is a major risk factor in the pathogenesis of optic nerve damage and glaucomatous visual field loss. Following topical ocular administration, brinzolamide is absorbed into the systemic circulation. Due to its affinity for carbonic anhydrase II, brinzolamide distributes extensively into the RBCs and exhibits a long half-life in whole blood (approximately 111 days). In humans, the metabolite N-desethyl brinzolamide is formed, which also binds to carbonic anhydrase and accumulates in RBCs. This metabolite binds mainly to carbonic anhydrase I in the presence of brinzolamide. In plasma, both parent brinzolamide and N-desethyl brinzolamide concentrations are low and generally below assay quantitation limits (less than 10 ng/mL). Binding to plasma proteins is approximately 60%. Brinzolamide is eliminated predominantly in the urine as unchanged drug. N-Desethyl brinzolamide is also found in the urine along with lower concentrations of the N-desmethoxypropyl and O-desmethyl metabolites. An oral pharmacokinetic study was conducted in which healthy volunteers received 1 mg capsules of brinzolamide twice per day for up to 32 weeks. This regimen approximates the amount of drug delivered by topical ocular administration of AZOPT dosed to both eyes 3 times per day and simulates systemic drug and metabolite concentrations similar to those achieved with long-term topical dosing. Red blood cell carbonic anhydrase activity was measured to assess the degree of systemic carbonic anhydrase inhibition. Brinzolamide saturation of RBC carbonic anhydrase II was achieved within 4 weeks (RBC concentrations of approximately 20 mcM). N-Desethyl brinzolamide accumulated in RBCs to steady-state within 20 to 28 weeks reaching concentrations ranging from 6 to 30 mcM. The inhibition of carbonic anhydrase II activity at steady-state was approximately 70% to 75%, which is below the degree of inhibition expected to have a pharmacological effect on renal function or respiration in healthy subjects.

AZOPT is a carbonic anhydrase inhibitor indicated in the treatment of elevated intraocular pressure (IOP) in patients with ocular hypertension or open-angle glaucoma. AZOPT is a carbonic anhydrase inhibitor indicated for the treatment of elevated intraocular pressure (IOP) in patients with ocular hypertension or open-angle glaucoma.

The recommended dose is one drop of AZOPT in the affected eye(s) 3 times daily. Shake well before use. AZOPT may be used concomitantly with other topical ophthalmic drug products to lower IOP. If more than one topical ophthalmic drug is being used, the drugs should be administered at least 10 minutes apart.

Most common adverse reactions (incidence 5% to 10%) are blurred vision and bitter, sour, or unusual taste. 1 To report SUSPECTED ADVERSE REACTIONS, contact Novartis Pharmaceuticals Corporation at 1-888-669-6682 or FDA at 1-800-FDA-1088 or www. gov/medwatch 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 the rates in the clinical trials of another drug and may not reflect the rates observed in practice. In clinical studies of AZOPT, the most frequently reported adverse reactions reported in 5% to 10% of patients were blurred vision and bitter, sour, or unusual taste. Adverse reactions occurring in 1% to 5% of patients were blepharitis, dermatitis, dry eye, foreign body sensation, headache, hyperemia, ocular discharge, ocular discomfort, ocular keratitis, ocular pain, ocular pruritus, and rhinitis. The following adverse reactions were reported at an incidence below 1%: allergic reactions, alopecia, chest pain, conjunctivitis, diarrhea, diplopia, dizziness, dry mouth, dyspnea, dyspepsia, eye fatigue, hypertonia, keratoconjunctivitis, keratopathy, kidney pain, lid margin crusting or sticky sensation, nausea, pharyngitis, tearing, and urticaria. The following adverse reactions have been identified during postapproval use of brinzolamide containing products. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Serious skin and subcutaneous tissue reactions, such as Stevens-Johnson syndrome (SJS) and Toxic epidermal necrolysis (TEN) may occur with the use of brinzolamide due to its sulfonamide component [see Warnings and Precautions (5.

AZOPT is contraindicated in patients who are hypersensitive to any component of this product. Hypersensitivity to any component of this product.

Risk Summary There are no adequate and well-controlled studies in pregnant women to inform drug-associated risk. In reproductive toxicity studies, brinzolamide administered orally to rats induced fetal toxicity at 375 times the recommended human ophthalmic dose (RHOD) based on mg/kg. In rabbits, no fetal toxicity was observed following oral administration (see Data) The background risk of major birth defects and miscarriage for the indicated population is unknown; however, in the U. general population, the estimated background risk of major birth defects is 2% to 4%, and of miscarriage is 15% to 20%, of clinically recognized pregnancies. Data Animal Data A peri-/postnatal study was conducted in rats administered brinzolamide by oral gavage from gestation day 16 through lactation day 20. Decreased pup body weight was observed at 15 mg/kg/day (313 times the RHOD based on mg/kg). The NOAEL for developmental toxicity was 5 mg/kg/day (104 times the RHOD). Following oral administration of 14 Risk Summary There are no data on the presence of brinzolamide in human milk, the effects on the breastfed infant, or the effects on milk production. Brinzolamide has been detected in the milk of lactating rats. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for AZOPT and any potential adverse effects on the breastfed child from AZOPT. A 3-month controlled clinical study was conducted in which AZOPT was dosed only twice a day in pediatric patients 4 weeks to 5 years of age. Patients were not required to discontinue their IOP-lowering medication(s) until initiation of monotherapy with AZOPT. IOP-lowering efficacy was not demonstrated in this study in which the mean decrease in elevated IOP was between 0 mmHg and 2 mmHg. Five out of 32 patients demonstrated an increase in corneal diameter of one millimeter. No overall differences in safety or effectiveness have been observed between elderly and younger patients.

2 There is a potential for an additive effect on the known systemic effects of carbonic anhydrase inhibition in patients receiving an oral carbonic anhydrase inhibitor and AZOPT. The concomitant administration of AZOPT and oral carbonic anhydrase inhibitors is not recommended. Carbonic anhydrase inhibitors may produce acid-base and electrolyte alterations. These alterations were not reported in the clinical trials with brinzolamide. However, in patients treated with oral carbonic anhydrase inhibitors, rare instances of acid-base alterations have occurred with high-dose salicylate therapy. Therefore, the potential for such drug interactions should be considered in patients receiving AZOPT.

OVERDOSAGE
Although no human data are available, electrolyte imbalance, development of an acidotic state, and possible nervous system effects may occur following oral administration of an overdose. Serum electrolyte levels (particularly potassium) and blood pH levels should be monitored.
NONCLINICAL TOXICOLOGY
Carcinogenesis Brinzolamide caused urinary bladder tumors in female mice at oral doses of 10 mg/kg/day and in male rats at oral doses of 8 mg/kg/day in 2-year studies. Brinzolamide was not carcinogenic in male mice or female rats dosed orally for up to 2 years. The carcinogenicity appears secondary to kidney and urinary bladder toxicity. These levels of exposure cannot be achieved with topical ophthalmic dosing in humans. Mutagenesis The following tests for mutagenic potential were negative: (1) in vivo in vivo E. coli in vitro Impairment of Fertility In reproduction studies of brinzolamide in rats, there were no adverse effects on the fertility or reproductive capacity of males or females at doses up to 18 mg/kg/day (375 times the RHOD based on mg/kg).
CLINICAL STUDIES
In two, 3-month clinical studies, AZOPT dosed 3 times per day in patients with elevated IOP, produced significant reductions in IOPs (4 mmHg to 5 mmHg). These IOP reductions are equivalent to the reductions observed with TRUSOPT* (dorzolamide hydrochloride ophthalmic solution) 2% dosed 3 times per day in the same studies. In 2 clinical studies in patients with elevated IOP, AZOPT was associated with less stinging and burning upon instillation than TRUSOPT* 2%.

Novartis Pharmaceuticals Corporation

AZOPT- brinzolamide_suspension/ drops Product manual source documgent