Tafluprost is a synthetic fluorinated prostaglandin analogue used as an ophthalmic active pharmaceutical ingredient for lowering elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension. It is also identified by the development code AFP-168 and is marketed in ophthalmic products including ZIOPTAN. PubChem and FDA records identify Tafluprost with CAS 209860-87-7, molecular formula C25H34F2O5, and molecular weight approximately 452.5 g/mol.
Tafluprost is a structurally modified analogue of prostaglandin F2α. The molecule contains a difluorinated phenoxybutenyl side chain and isopropyl ester functionality, giving it the physicochemical characteristics associated with a lipophilic prostaglandin analogue.
Tafluprost is an optically active, stereochemically defined small molecule. Its chemical name is propan-2-yl (Z)-7-[(1R,2R,3R,5S)-2-[(E)-3,3-difluoro-4-phenoxybut-1-enyl]-3,5-dihydroxycyclopentyl]hept-5-enoate. FDA GSRS identifies Tafluprost under UNII 1O6WQ6T7G3.
The API is distinct from tafluprost free acid, which has the molecular formula C22H28F2O5 and molecular weight 410.5 g/mol. Tafluprost itself is the isopropyl ester drug substance.
Tafluprost is a selective FP prostanoid receptor agonist. Following topical ocular administration, tafluprost is hydrolyzed to its active metabolite, tafluprost acid. Tafluprost acid activates FP receptors and lowers intraocular pressure primarily by increasing uveoscleral outflow of aqueous humor.
The mechanism makes Tafluprost an important prostaglandin analogue API for ophthalmic pharmaceutical development.
Tafluprost is primarily used in ophthalmic formulations intended for the treatment of open-angle glaucoma and ocular hypertension. FDA labeling describes a 0.0015% ophthalmic solution administered as one drop in the affected eye(s) once daily in the evening.
The marketed U.S. formulation contains 0.015 mg/mL Tafluprost, equivalent to the 0.0015% ophthalmic solution. The finished formulation also contains glycerol, sodium dihydrogen phosphate dihydrate, disodium edetate, polysorbate 80 and water for injection, with hydrochloric acid or sodium hydroxide used for pH adjustment.
Tafluprost is described by FDA as a colorless to light-yellow viscous liquid and is practically insoluble in water.
A pharmaceutical industry technical source reports that Tafluprost is very soluble in acetone, acetonitrile, dichloromethane, diethyl ether, ethanol and methanol, while being practically insoluble in water and n-heptane. It also reports an optical rotation of +24.0° to +29.0° under its stated measurement conditions. This is useful as a reference characteristic, but should not automatically be substituted for a registered API specification.
Tafluprost drug substance requires control of identity, assay, related substances, residual solvents, water content and stereochemical/enantiomeric purity. FDA's original review specifically identifies IR identity, optical rotation, related substances, residual solvents, water content, assay and enantiomeric impurity among the sponsor's drug-substance quality tests.
However, the numerical acceptance criteria for these tests in the FDA review are redacted. Therefore, numerical API release limits should not be invented for CMS publication.
Tafluprost is a chemically synthesized small-molecule API requiring control of stereochemistry, reaction-related impurities, residual solvents and final physical characteristics. The manufacturing process should incorporate validated analytical procedures capable of confirming molecular identity and controlling related substances and enantiomeric impurities.
Tafluprost API should be stored in suitable pharmaceutical-grade, well-closed containers under validated conditions that protect the material from light, moisture and other environmental exposure. Because Tafluprost is a viscous liquid and is sensitive to physicochemical degradation, appropriate container-closure compatibility and stability controls are important.
The finished ZIOPTAN ophthalmic solution is a separate formulation and should not be confused with the API's own storage specification. FDA describes the finished product as a sterile solution with pH 5.5–6.7 and osmolality 260–300 mOsmol/kg.
A pharmaceutical-grade Tafluprost API package may include a Certificate of Analysis, specification sheet, analytical methods, residual-solvent data, impurity profile, stability information, safety documentation and regulatory documentation applicable to the intended market.
A qualified Tafluprost API manufacturer in India should maintain stringent control of identity, assay, related substances, residual solvents, water content and stereochemical purity. For this ophthalmic prostaglandin analogue, reliable control of the drug substance is essential for consistent quality of finished ophthalmic formulations.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Melting Point | +24.0° to +29.0 |