XALATAN - latanoprost solution
Dispensing Solutions, Inc.
DESCRIPTION
Latanoprost is a prostaglandin F2? analogue. Its chemical name is isopropyl-(Z)-7[(1R,2R,3R,5S)3,5-dihydroxy-2-[(3R)-3-hydroxy-5-phenylpentyl]cyclopentyl]-5-heptenoate. Its molecular formula is C26 H40 O5
Latanoprost is a colorless to slightly yellow oil that is very soluble in acetonitrile and freely soluble in acetone, ethanol, ethyl acetate, isopropanol, methanol and octanol. It is practically insoluble in water.
XALATAN Sterile Ophthalmic Solution (latanoprost ophthalmic solution) is supplied as a sterile, isotonic, buffered aqueous solution of latanoprost with a pH of approximately 6.7 and an osmolality of approximately 267 mOsmol/kg. Each mL of XALATAN contains 50 micrograms of latanoprost. Benzalkonium chloride, 0.02% is added as a preservative. The inactive ingredients are: sodium chloride, sodium dihydrogen phosphate monohydrate, disodium hydrogen phosphate anhydrous and water for injection. One drop contains approximately 1.5 �g of latanoprost.
CLINICAL PHARMACOLOGY
Mechanism of Action
Latanoprost is a prostanoid selective FP receptor agonist that is believed to reduce the intraocular pressure (IOP) by increasing the outflow of aqueous humor. Studies in animals and man suggest that the main mechanism of action is increased uveoscleral outflow. Elevated IOP represents a major risk factor for glaucomatous field loss. The higher the level of IOP, the greater the likelihood of optic nerve damage and visual field loss.
Pharmacokinetics/Pharmacodynamics
Absorption
Latanoprost is absorbed through the cornea where the isopropyl ester prodrug is hydrolyzed to the acid form to become biologically active. Studies in man indicate that the peak concentration in the aqueous humor is reached about two hours after topical administration.
Distribution
The distribution volume in humans is 0.16 � 0.02 L/kg. The acid of latanoprost can be measured in aqueous humor during the first 4 hours, and in plasma only during the first hour after local administration.
Metabolism
Latanoprost, an isopropyl ester prodrug, is hydrolyzed by esterases in the cornea to the biologically active acid. The active acid of latanoprost reaching the systemic circulation is primarily metabolized by the liver to the 1,2-dinor and 1,2,3,4-tetranor metabolites via fatty acid ?-oxidation.
Excretion
The elimination of the acid of latanoprost from human plasma is rapid (t1/2 =17 min) after both intravenous and topical administration. Systemic clearance is approximately 7 mL/min/kg. Following hepatic ?-oxidation, the metabolites are mainly eliminated via the kidneys. Approximately 88% and 98% of the administered dose is recovered in the urine after topical and intravenous dosing, respectively.
Xalatan Indications and Usage
XALATAN Sterile Ophthalmic Solution is indicated for the reduction of elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension.
DOSAGE AND ADMINISTRATION
The recommended dosage is one drop (1.5 �g) in the affected eye(s) once daily in the evening. If one dose is missed, treatment should continue with the next dose as normal.
The dosage of XALATAN Sterile Ophthalmic Solution should not exceed once daily; the combined use of two or more prostaglandins, or prostaglandin analogs including XALATAN Sterile Ophthalmic Solution is not recommended. It has been shown that administration of these prostaglandin drug products more than once daily may decrease the intraocular pressure lowering effect or cause paradoxical elevations in IOP.
Reduction of the intraocular pressure starts approximately 3 to 4 hours after administration and the maximum effect is reached after 8 to 12 hours.
XALATAN may be used concomitantly with other topical ophthalmic drug products to lower intraocular pressure. If more than one topical ophthalmic drug is being used, the drugs should be administered at least five (5) minutes apart.
HOW SUPPLIED
XALATAN Sterile Ophthalmic Solution is a clear, isotonic, buffered, preserved colorless solution of latanoprost 0.005% (50 �g/mL). It is supplied as a 2.5 mL solution in a 5 mL clear low density polyethylene bottle with a clear low density polyethylene dropper tip, a turquoise high density polyethylene screw cap, and a tamper-evident clear low density polyethylene overcap.
2.5 mL fill, 0.005% (50 �g/mL)
Package of 1 bottle NDC 0013-8303-04
Storage
Protect from light. Store unopened bottle(s) under refrigeration at 2� to 8�C (36� to 46�F). During shipment to the patient, the bottle may be maintained at temperatures up to 40�C (104�F) for a period not exceeding 8 days. Once a bottle is opened for use, it may be stored at room temperature up to 25�C (77�F) for 6 weeks.
Rx only
