Tafluprost

Absorption

Following instillation, tafluprost is absorbed through the cornea and is hydrolyzed to the biologically active acid metabolite, tafluprost acid. Tafluprost is an ester which makes the drug lipophillic enough to be quickly absorbed through. When administered to the eye, the peak plasma concentration (Cmax) and time to peak plasma concentration (Tmax) of tafluprost acid in healthy subjects was 26 pg/mL and 10 minutes respectively. a AUC, tafluprost acid = 394 pgmin/mL - 432 pgmin/mL.

Toxicity

Most common ocular adverse reaction is conjunctival hyperemia (range 4% – 20%).

Description

Glaucoma is second only to cataracts as a causative factor of blindness. By 2010, it is estimated that approximately 60 million people worldwide will be afflicted by glaucoma, so effective treatments should garner a large market. PG analogs have been widely used for lowering IOP by increasing uveoscleral outflow through agonism of the prostanoid FP receptor, and currently marketed versions include latanoprost, unoprostone isopropyl ester, bimatoprost, and travoprost. Compared to the carboxylic acid of latanaprost (K_i=4.7 nM), the carboxylic acid of tafluprost displayed a 10-fold greater affinity for the prostanoid FP receptor (K_i=0.4 nM). The synthesis of tafluprost begins with a Wittig condensation of the protected bicyclic lactone carbaldehyde with a dimethyl phosphonate ketone derivative.
Compared to the carboxylic acid of latanaprost (Ki 4.7 nM), the carboxylic acid of tafluprost displayed a 10-fold greater affinity for the prostanoid FP receptor (Ki 0.4 nM). The synthesis of tafluprost begins with a Wittig condensation of the protected bicyclic lactone carbaldehyde with a dimethyl phosphonate ketone derivative. The bottom appendage is then completed by the fluorination of the ketone with morpholino-sulfur trifluoride. Hydrolysis of the benzoate ester protecting group liberates the hydroxy group, and reduction of the lactone is accomplished with aluminum hydride to generate the lactol. Condensation of this intermediate with the phosphonium salt of the acid side chain generates the free acid, or active ingredient, which is subsequently esterified with 2-iodopropane in the presence of DBU. .

The Uses of Tafluprost

Tafluprost is a novel prostanoid used in the treatment of glaucoma and is the first prostanoid to be released in a preservative free-formula.

Background

A prostaglandin analogue ester prodrug used topically (as eye drops) to control the progression of glaucoma and in the management of ocular hypertension. Chemically, tafluprost is a fluorinated analog of prostaglandin F2-alpha. Tafluprost was approved for use in the U.S. on February 10, 2012.

Indications

Tafluprost is indicated for reducing elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension.

What are the applications of Application

Tafluprost is an FP receptor agonist

Pharmacokinetics

Tafluprost is a novel prostaglandin analog with a high affinity for the fluoroprostaglandin (FP) receptor PGF2α. Tafluprost has an affinity for the FP receptor that is approximately 12 times higher than that of the carboxylic acid of latanoprost, but with almost no potential to bind to other receptors.

Metabolism

Tafluprost is an ester prodrug which is rapidly hydrolyzed by corneal esterases to form its biologically active acid metabolite. Tafluprost acid is further metabolized via fatty acid β-oxidation and phase II conjugation into 1,2,3,4-tetranor acid.