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To evaluate the ocular penetration of ISV-304 (ketorolac tromethamine) formulated in DuraSite(®) or DuraSite(®) 2 compared to Acular LS(®) (0.4% ketorolac ophthalmic solution) in rabbits.The left eye of rabbits received a single topical instillation of either ISV-304 (0.2% and 0.4% ketorolac) in DuraSite, ISV-304 (0.2% and 0.4% ketorolac) in DuraSite 2, or Acular LS. At predetermined time points, aqueous humor (AH) levels of ketorolac were measured by HPLC-MS/MS, and Cmax, Tmax, and AUC0.25-24h were determined.The highest mean concentration of ketorolac was achieved in ISV-304 (0.4%) formulated in DuraSite 2 with a Cmax value of 1889 ± 884 ng/mL, compared to Cmax values for ISV-304 (0.4%) formulated in DuraSite (1212 ± 435 ng/mL) or Acular LS (275 ± 83 ng/mL). ISV-304 (0.2%) formulations also achieved higher AH Cmax values (801 ± 205 ng/mL and 1077 ± 415 ng/mL) compared to Acular LS. There was a significant increase in drug exposure in the ISV-304 (0.4%) formulated in DuraSite 2 or DuraSite formulations with AUC0.25-24h values 6836 ng/mL*h and 5684 ng/mL*h, respectively, compared to Acular LS with an AUC0.25-24h value of 1424 ng/mL*h. ISV-304 (0.2%) formulations also had high AUC0.25-24h values (3241 ng/mL*h and 4490 ng/mL*h), which were a 2.3-3.2-fold increase over the Acular LS AUC0.25-24h value.DuraSite and DuraSite 2 delivery systems markedly improved the ketorolac ocular pharmacokinetic parameters in rabbits. DuraSite formulations may lessen the side effects associated with topical nonsteroidal anti-inflammatory drug use by maintaining efficacy with a reduced dosing regimen and reduced active ingredient.

The purpose of this study was to compare the ocular pharmacokinetics of experimental solutions of bromfenac in DuraSite(®) to Xibrom™ (bromfenac ophthalmic solution) 0.09%.The bromfenac content was measured in the aqueous humor of 84 Dutch Belted rabbits after a single dose of either 0.045% or 0.09% bromfenac in DuraSite in the left eye and the commercial preparation in the right eye. The drug content in the aqueous humor was measured at 0.5, 1, 2, 4, 8, 12, and 24 h after instillation. In a separate multi-dose study, rabbits received one drop of the 0.09% experimental or commercial preparation, 3 times daily for 14 days. For both experiments the drug content in ocular tissues was analyzed using liquid chromatography atmospheric pressure ionization tandem mass spectrometry.In single-dose experiments, the concentration of bromfenac in the aqueous humor was higher with the experimental preparations than with the commercial solution. The area under the concentration-time curve of 0.045% and 0.09% bromfenac in DuraSite was ∼2 and 4-fold higher than that of commercial bromfenac ophthalmic solution, 0.09%. After multi-dose experiments, ocular tissue concentrations of bromfenac were ∼3 times higher for the experimental than for the commercial formulation.The study demonstrates that the DuraSite topical drug delivery system can deliver bromfenac to various ocular tissues and attain considerably higher concentrations than the commercially available eye drop formulation. The higher aqueous concentration sustained with these experimental formulations could broaden the utility of bromfenac and/or reduce the currently approved dosing frequency of this drug.

Azithromycin is an azalide class of antibiotic with pharmacodynamics that have made it a valuable agent in the treatment of soft tissue infections. In ophthalmology, oral administration of azithromycin has been proven effective for the treatment of trachoma. However, topical formulations of azithromycin to treat ocular surface infections have been challenging to develop because of the drug's hydrophobicity and instability in aqueous solutions at pH levels that are comfortable in the eye. The design of a polycarbophil polymer-based delivery system for a topical formulation of azithromycin was evaluated for its ability to provide drug stability, comfort, and increased retention of the formulation in the eye.Formulations of 0.5% and 1.0% azithromycin were created in polycarbophil, a lightly cross-linked polyacrylic acid polymer that was adjusted to a viscosity, pH, and osmolality that are suitable for dispensing in the eye.The polycarbophil-based ophthalmic delivery system, DuraSite (InSite Vision, Alameda, CA), helps solubilize azithromycin and retard its degradation in aqueous solution. The formulation was stable at room temperature as well as 5 degrees C. Upon administration of a single drop of 1% azithromycin in DuraSite ophthalmic solution in rabbits' eyes, tear concentrations of azithromycin ranged from 87 to 288 microg/g and high concentrations were sustained for over a 24-h period.Azithromycin can be developed as an eyedrop in an aqueous ocular delivery system for the treatment of ocular surface infections. The ocular delivery system, DuraSite solubilizes azithromycin at a high concentration in an aqueous solution and protects it from degradation during manufacture and storage. The development of azithromycin in this delivery system enhances the antibiotic's usefulness in ophthalmology for the topical treatment of ocular surface bacterial infections and lid margin diseases.

Purpose: The pharmacokinetics of a 2% ocular solution of azithromycin in DuraSite was evaluated in rabbits to determine whether the PK/PD parameters support a once-a-day for three-day therapeutic regimen against bacterial conjunctivitis. Materials and Methods: Mean levels of azithromycin were determined in tears, bulbar conjunctiva, cornea, and plasma following a single drop of 2% azithromycin. The levels were determined by HPLC-MS. Results: Concentrations of azithromycin peaked at 30 minutes. At the end of 24 hours, ocular tissue concentrations exceeded the MIC breakpoint for the most common causative pathogens of bacterial conjunctivitis by at least 7-fold. Conclusion: The PK/PD profile of 2% azithromycin suggests efficacy against common causative bacteria with just one dose per day for three days.

To analyze the effect of azithromycin 1% ophthalmic solution in DuraSite (InSite Vision, Inc, Alameda, California, USA) on bacterial conjunctivitis.Prospective, randomized, vehicle-controlled, parallel-group, double-masked multicenter clinical study.Eligible male or female participants with a clinical diagnosis of acute bacterial conjunctivitis were randomized to either 1% azithromycin in DuraSite or vehicle for five days. Infected eyes were dosed twice daily on days 1 and 2 and once daily on days 3 through 5. Conjunctival cultures were obtained at baseline, visit 2 (day 3 or 4), and visit 3 (day 6 or 7). The primary end point was clinical resolution of signs and symptoms (rating of zero on ocular discharge, bulbar and palpebral injection) at visit 3. Efficacy measures were clinical resolution and bacterial eradication as evaluated in the per-protocol population. Safety was assessed by adverse events, slit-lamp findings, and ophthalmoscopy.Two hundred and seventy-nine participants (n = 130, 1% azithromycin in DuraSite; n = 149, vehicle), age one to 96 years, were evaluated for efficacy. Clinical resolution with azithromycin ophthalmic solution was statistically significant compared with that of vehicle (P = .030) at visit 3. Bacterial eradication rates with azithromycin ophthalmic solution reached 88.5% at visit 3 (P.001) and included some pathogens resistant to azithromycin in vitro. Overall, adverse event rates were similar in both treatment groups.Azithromycin 1% ophthalmic solution in DuraSite showed statistically significant differences in clinical resolution and bacterial eradication rates when compared with vehicle. Because it was well tolerated in this population, it may be a viable treatment option for children and adults with bacterial conjunctivitis.

Afshin Shafiee,1 Lyle M Bowman,2 Eddie Hou,2 Kamran Hosseini1,3 1Preclinical, 2Development, 3Clinical, InSite Vision, Alameda, CA, USA Purpose: To compare the aqueous humor (AH) and iris-ciliary body (ICB) concentration of bimatoprost in rabbit eyes treated with ISV-215 (0.03% bimatoprost formulated in DuraSite) with the marketed product bimatoprost 0.03% ophthalmic solution. Methods: The left eye of rabbits received a single topical instillation of either ISV-215 (n = 32 eyes) or bimatoprost 0.03% (n = 32 eyes). At predetermined time points, levels of bimatoprost and bimatoprost acid in the AH and the ICB were quantified by HPLC-MS/MS. Results: Both bimatoprost and bimatoprost acid were detected in the AH and the ICB within 15 minutes of dosing. Bimatoprost acid concentrations in both compartments were markedly higher than bimatoprost. There was a statistically significant (P < 0.01) increase in the concentration of the prodrug in the AH and its acid form in the ICB in animals treated with ISV-215 compared to bimatoprost 0.03%. In the ISV-215-treated rabbit eyes, the highest concentrations of bimatoprost and bimatoprost acid were in the ICB and AH, respectively, while in the bimatoprost 0.03%-treated eyes, no differences in the drug content of the selected ocular tissues were observed. Conclusions: Bimatoprost 0.03% formulated in DuraSite has superior ocular distribution and area under the curve compared to bimatoprost 0.03% in rabbit eyes. This improvement in the pharmacokinetic parameters of ISV-215 may provide us with a better platform to optimize a bimatoprost formulation that offers the same degree of efficacy in lowering intraocular pressure and improved therapeutic index in glaucomatous patients by lessening the ocular side effects associated with long-term use of topical prostaglandin F2α analogs. Keywords: drug delivery, intraocular pressure, glaucoma, aqueous humor, prostaglandin (PGF2α) analogs

The use of poly(methyl methacrylate) (PMMA) in corneal contact lenses led to the popularization of the contact lens in the early 1950s. PMMA is lighter than glass, clear, rigid, and relatively inert biologically. Its largest failing as a contact lens material is its lack of oxygen permeability, and a variety of materials have since been developed to overcome the oxygen deprivation problem that arises with PMMA lenses. More modern contact lens materials have much higher oxygen permeability than PMMA, and most of these materials fall into one of two categories: (1) soft hydrogels, or (2) rigid gas permeable. The chemical compositions and physical properties of both types of materials will be discussed.

In the development of contact lens material, characterization of the materials includes measurement of gas transport, and mechanical properties, including the modulus of elasticity, tensile strength, percent elongation and tear strength. Physical properties determined on contact lens plastics include percent hydration, wetting angles, glass transition temperature, percent visible transmission, indentation hardness, refractive index, and percent linear expansion. In addition to polymer measurements, the protein and lipid deposition must be measured to determine biocompatibility in the eye. Each of the measurements must be performed on a finished contact lens which weighs 10 mg at a thickness 0.01 cm. This paper will describe how each of the listed measurements is performed on a contact lens and representative measurements will be given for contact lens polymers. This data will include both rigid gas permeable and hydrogel contact lenses.

Every month, 4–5 new patents for contact lens materials appear in the international chemical literature. However, rarely do more than one or two new materials reach the market during the year. In addition, almost all new materials are minor variations of the basic lens polymers that have been available for the last 10 to 15 years. The problem which keeps the new materials from entering the marketplace is not a lack of demand for improved materials, but that most of the potential polymers satisfy only one or two of the requirements for clinical success. This paper will discuss 20 aspects of lens polymers which must be considered by investigators hoping to bring their new polymer to the ophthalmic market.

Purpose To compare the safety and tolerability of 1.0% azithromycin in a polymeric mucoadhesive delivery system with 0.3% tobramycin ophthalmic solution for the treatment of bacterial conjunctivitis. Methods This study was a prospective, randomized, active-controlled, double-masked, phase 3 trial conducted from August 6, 2004, to October 6, 2005, at 47 sites. Subjects with a clinical diagnosis of bacterial conjunctivitis were randomly assigned to receive either 1% azithromycin in DuraSite (AzaSite; InSite Vision, Alameda, CA) (n = 365) or 0.3% tobramycin (n = 378). Both groups received masked medication four times daily for 5 days, but participants received an active dose of 1% azithromycin in DuraSite only twice a day on days 1 and 2 and daily on days 3 to 5. Conjunctival cultures were taken, and ocular signs and symptoms were evaluated at baseline and at two follow-up visits. Results A total of 743 patients were randomized, and 710 (96%) completed the trial. Both study medications were well tolerated. The most frequently observed ocular adverse events in the azithromycin group were eye irritation (1.9%), conjunctival hyperemia (1.1%), and worsening bacterial conjunctivitis (1.1%). These rates compared favorably with those obtained with tobramycin. Rates of microbial eradication (an efficacy parameter) and bacterial infection recurrence (a safety parameter) were the same in both groups. Conclusions This is the first report of the safety and tolerability of a commercially manufactured preparation of azithromycin for ophthalmic use. Azithromycin 1% in DuraSite is safe and can be administered in a regimen of less frequent doses than can tobramycin, while producing an equivalent clinical outcome. The formulation is well tolerated in patients over the age of 1 year for the eradication of bacteria commonly associated with conjunctivitis. (ClinicalTrials.gov number, NCT00105469.).

The versatility of dense gases or supercritical fluids as solvents is briefly reviewed., It is pointed out that gas density is the key parameter controlling solvent power and it is argued that density programming should replace pressure programming for chro-matographlc and extractive separations. Our previous theory of dense gas solubility and solubility thresholds is then used to explain why relatively high pressures are desirable for dense gas separations. The theory is also used to examine peak spacing for linear density programs to develop a speeial density program for uniform peak spacing. An experimental linear density programming system utilizing CO2 at 40 C and at pressures up to 300 atmospheres is described and factors affecting separation efficiency are evaluated. A separation of four aromatic compounds is demonstrated using programmed density extraction alone. Chromatographic columns used with polystyrene oligomers and polynuclear aromatic compounds are shown to improve the separation....