Brinzolamide

12.1 Mechanism of Action 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.

1 INDICATIONS AND USAGE 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. ( 1 )

2 DOSAGE AND ADMINISTRATION 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. • Instill one drop in the affected eye(s) 3 times daily. ( 2 ) • If more than one topical ophthalmic drug is being used, the drugs should be administered at least 10 minutes apart. ( 2 )

6 ADVERSE REACTIONS Most common adverse reactions (incidence 5% to 10%) are blurred vision and bitter, sour, or unusual taste. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Sandoz Inc. at 1-800-525-8747 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 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 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. 6.2 Postmarketing Experience 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 (5.1)] .

7 DRUG INTERACTIONS • There is a potential additive effect of the known systemic effects of carbonic anhydrase inhibition in patients receiving both oral and topical carbonic anhydrase inhibitors. ( 7.1 ) • Rare instances of acid-base alterations have occurred with high-dose salicylate therapy. ( 7.2 ) 7.1 Oral Carbonic Anhydrase Inhibitors 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. 7.2 High-Dose Salicylate Therapy 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.