Effect of benzalkonium chloride-free latanoprost ophthalmic solution on ocular surface in patients with glaucoma

COMfort Eye Trial (COMET) results - a non-inferiority, randomized, investigator-masked, two-parallel group, phase III clinical trial, to evaluate the efficacy and safety of a preservative free formulation of latanoprost versus a reference drug (Xalatan®) in patients with primary open-angle glaucoma (POAG) or ocular hypertension (OHT)

AIM

To prove non-inferiority of preservative-free (PF) latanoprost versus benzalkonium chloride (BAK) containing latanoprost in lowering intraocular pressure (IOP) in primary open-angle glaucoma (POAG) or ocular hypertension (OHT) patients.

DESIGN AND METHODS

This phase III, randomized, investigator-masked trial primarily aimed to demonstrate non-inferiority of YSLT PF latanoprost 50 μg/ml (Yonsung GmbH) to latanoprost (Xalatan®) 50 μg/ml (Pfizer) in reducing IOP from Baseline to Week 12. Secondary aims included conjunctival hyperemia evaluation and difference in ocular comfort levels. Total 130 patients with POAG or OHT were enrolled and randomized (1:1 ratio) to receive YSLT or latanoprost, instilling eye drops daily for 12 weeks.

RESULTS

At Week 12, mean diurnal IOP reduction was -7.67 ± 2.104 mmHg for YSLT PF latanoprost and -7.77 ± 2.500 for latanoprost. The 97.5% confidence interval of between-treatment group difference in IOP reduction from Baseline to Week 12 was [-0.846, +∞), not crossing the non-inferiority margin of -1.5 mmHg. A low incidence of mild topical treatment emergent adverse events (TEAEs) was observed in both groups, while no serious TEAEs were reported.

CONCLUSIONS

YSLT eye drops demonstrated non-inferiority to latanoprost in reducing IOP. Both products were well tolerated without serious TEAEs reported.

Posaconazole micelles for ocular delivery: in vitro permeation, ocular irritation and antifungal activity studies

Posaconazole (PSC) is a triazole group anti-fungal agent with the widest spectrum. Although there is no commercially available ocular dosage form, its diluted oral suspension preparation (Noxafil®) is used as off-label in topical treatment of severe keratitis and sclerokeratitis in the clinic. However, ocular bioavailability of PSC suspension form is extremely low due to its highly lipophilic character. Thus, there is a clinical need to improve its ocular bioavailability and to develop novel delivery system for the treatment of ocular fungal infections. Herein, we studied ex vivo permeation, penetration, anti-fungal activity, and Hen's Egg Test-Chorioallantoic Membrane (HET-CAM) toxicity tests in order to assess ocular targeting of PSC micelles, which were optimized in our previous study. The results indicated that micellar carrier system increased the permeability of PSC to eye tissues. Micelles showed higher affinity to ocular tissues than that of commercial oral suspension of PSC (Noxafil®). In vitro anti-fungal activity data also confirmed the efficacy of PSC loaded micellar formulations against Candida. albicans strains. The relative safety of the optimized micelles on the ocular tissue was shown with the HET-CAM toxicity test. In conclusion, micellar systems could be a promising strategy for the effective and safe delivery of PSC in the treatment of ocular fungal infections.

Optimization of the Micellar-Based In Situ Gelling Systems Posaconazole with Quality by Design (QbD) Approach and Characterization by In Vitro Studies

Background: Fungal ocular infections can cause serious consequences, despite their low incidence. It has been reported that Posaconazole (PSC) is used in the treatment of fungal infections in different ocular tissues by diluting the oral suspension, and successful results were obtained despite low ocular permeation. Therefore, we optimized PSC-loaded ocular micelles and demonstrated that the permeation/penetration of PSC in ocular tissues was enhanced. Methods: The micellar-based in situ gels based on the QbD approach to increase the ocular bioavailability of PSC were developed. Different ratios of Poloxamer 407 and Poloxamer 188 were chosen as CMAs. Tsol/gel, gelling capacity and rheological behavior were chosen as CQA parameters. The data were evaluated by Minitab 18, and the formulations were optimized with the QbD approach. The in vitro release study, ocular toxicity, and anti-fungal activity of the optimized formulation were performed. Results: Optimized in situ gel shows viscoelastic property and becomes gel form at physiological temperatures even when diluted with the tear film. In addition, it has been shown that the formulation had high anti-fungal activity and did not have any ocular toxicity. Conclusions: In our previous studies, PSC-loaded ocular micelles were developed and optimized for the first time in the literature. With this study, the in situ gels of PSC for ocular application were developed and optimized for the first time. The optimized micellar-based in situ gel is a promising drug delivery system that may increase the ocular permeation and bioavailability of PSC.

Pharmacokinetics and Pharmacology of Latanoprost 0.005% without Benzalkonium Chloride Vs Latanoprost 0.005% with Benzalkonium Chloride in New Zealand White Rabbits and Beagles

Purpose: Many intraocular pressure (IOP)-lowering medications contain benzalkonium chloride (BAK), a preservative associated with unfavorable outcomes.A formulation of latanoprost 0.005% ophthalmic without BAK is approved by the FDA and indicated for reduction of IOP in patients with open-angle glaucoma or ocular hypertension. We present two preclinical studies of latanoprost 0.005% BAK-free vs latanoprost with BAK; one examining plasma and ocular tissue pharmacokinetics (PK) in New Zealand white rabbits, and one comparing in vivo IOP-lowering efficacy in healthy beagles.Methods: In the PK study, one drop of treatment (latanoprost BAK-free or latanoprost with BAK) was instilled into both eyes of rabbits in each treatment group (n = 18). At 0.25, 0.5, 1, 4, 6, and 24 hours postdose, three rabbits per study group underwent terminal blood and tissue collection.In the IOP study, in the first dosing period, both eyes of each beagle received either 1 drop latanoprost BAK-free or latanoprost with BAK, once daily for 10 days. After a 10-day washout period, a second 10-day dosing period was conducted and latanoprost BAK-free or latanoprost with BAK were dosed in the opposite eyes, respectively. IOP measurements were taken at 1, 6, and 12 hours postdose.Results: The maximum plasma concentration for latanoprost BAK-free and latanoprost with BAK occurred 0.25 hours after administration (174.1 vs 217.2 pg/mL, respectively). Area under the concentration time curve from zero to infinity was highest in aqueous humor for latanoprost BAK-free and latanoprost with BAK (133.1 vs 119.6 hr·ng/mL, respectively) and was not estimable in vitreous humor. In beagles, once-daily administration of latanoprost BAK-free or latanoprost with BAK led to a significant reduction in IOP vs baseline (P < .001); there was no difference between groups (P > .05).Conclusions: Latanoprost BAK-free showed comparable activity in reducing IOP, and comparable plasma and ocular PK parameters to latanoprost with BAK.

Physiochemical Properties and Cytotoxicity of a Benzalkonium Chloride-Free, Micellar Emulsion Ophthalmic Formulation of Latanoprost

Purpose

Prostaglandin derivatives are used widely to reduce intraocular pressure associated with open-angle glaucoma. The most widely used prostaglandin derivative, latanoprost, is available in an ophthalmic solution that is solubilized and preserved with 0.02% benzalkonium chloride (BAK), which has been shown to be cytotoxic to corneal cells. Latanoprost ophthalmic solution with BAK requires specific storage temperatures, which can impact the supply cycle. Here, we describe the production, physicochemical characteristics, and cytotoxicity profile of a micelle formulation that solubilizes latanoprost without the need for BAK.

Methods

The optimum concentration of castor oil with the surfactant polyethylene glycol (15) hydroxystearate was determined, and the mixture stirred. Various surfactants were tested to determine the ideal mixture to form a micelle formulation. Viscosity, zeta potential, surface tension, droplet size, and osmolality of the batches were tested. The cytotoxicity of the micelle formulation was determined in a corneal cell viability assay that compared positive and negative controls, latanoprost without BAK, latanoprost with BAK, and placebo.

Results

A castor oil concentration of 0.15% produced a micelle formulation with a diameter of <100 nm. This micelle formulation had unique characteristics that were not mimicked when either the surfactant or the oil was changed. The physicochemical characteristics in multiple batches of the micelle formulation did not vary significantly between batches. Long-term and accelerated stability studies showed latanoprost potency remained constant for 24 months at 25°C/75% relative humidity (RH) and at 40°C/25% RH for 6 months.

Conclusion

The micelle formulation technology system is capable of solubilizing latanoprost in an ophthalmic formulation without the need for BAK. The system is stable at room temperature.

Extracellular MMP-9-Based Assessment of Ocular Surface Inflammation in Patients with Primary Open-Angle Glaucoma

Purpose

Objective assessment of dry eye disease (DED) severity and ocular inflammation using the InflammaDry® test for extracellular matrix metalloproteinase-9 (MMP-9) and the impact of antiglaucoma eye drops in people with primary open-angle glaucoma (POAG).

Methods

Overall, 90 adults (180 eyes) were included: 60 had been diagnosed with POAG and were treated with prostaglandin analogue monotherapy and 30 were suspected of having POAG but did not receive any treatment (control group). Of those treated with prostaglandin eye drops, 30 received a preservative-free formulation (tafluprost) and 30 were treated with a formulation containing the preservative benzalkonium chloride (BAK) (latanoprost). Measurement of extracellular MMP-9 levels (InflammaDry test) provided a marker for ocular surface inflammation. Further assessments of disease severity and inflammation comprised Goldmann applanation tonometry for intraocular pressure (IOP), Schirmer's test with anesthesia, ocular surface staining with unpreserved fluorescein (Oxford scale index), tear breakup time (TBUT), McMonnies questionnaire, and the Ocular Surface Disease index (OSDI).

Results

Clinically significant MMP-9 levels (>40 ng/mL) were detected in tear film from 46.7% of subjects treated with BAK-containing medication. In contrast, only 16.7% of subjects treated with preservative-free medication or untreated individuals demonstrated similar MMP-9 levels. This difference was statistically significant (p < 0.05). MMP-9 results correlated with other indicators of inflammation and disease severity. BAK-containing medication was associated with rapid TBUT (<5 seconds) in 50% of cases, while only 10% of untreated subjects and individuals using preservative-free medication demonstrated comparable TBUT results.

Conclusion

Measurement of ocular surface MMP-9 level provides a useful marker for inflammation and DED in POAG. Use of a preservative-free topical prostaglandin formulation results in lower levels of ocular inflammation, compared with BAK-containing medication.

Ocular Surface Disease with BAK preserved Travoprost and Polyquaternium 1(Polyquad) preserved Travoprost

Introduction. The topical medications containing benzalkonium chloride (BAK) as preservative is known to induce corneal toxicity and ocular surface disease (OSD) in glaucoma patients. Newer preservatives like SofZia or polyquaternium-1 (Polyquad) have been developed to replace BAK in many medications. The present study aimed at comparing the OSD in glaucoma patients receiving BAK preserved travoprost versus travoprost with polyquad as preservative and controls not receiving any medications. Methods. This prospective, controlled, observational study was conducted on patients of primary open angle glaucoma (POAG) on medications for more than 6 months. The first group comprised of 40 patients receiving BAK preserved travoprost, the second group included 40 patients receiving polyquad preserved travoprost and 30 of control group not receiving any medical treatment. Ocular Surface Disease Index (OSDI) scores using Ocular Surface Disease Index (OSDI) Questionnaire were assessed and compared in all subjects. Results. The mean OSDI score was 29.09 ± 13.45 in BAK group, 12.4 ± 5.085 in polyquad group and 10.93 ± 7.36 in controls. The mean difference in OSDI scores between BAK and polyquad group 16.63 (p < 0.05) and between the BAK and control group was 18.96 (p < 0.05). The mean difference in OSDI scores between the polyquad and control group was 1.53 (p > 0.05). The mean IOP in the BAK group was 19.2 ± 3.5 and in polyquad group was 20.1 ± 4.2. The IOP measured at 12 months of treatment was 13.2 ± 2.1 in BAK group and 12.8 ± 3.3 in polyquad group. The IOP measured at baseline and 12 months showed statistically significant difference in both the groups (p <o.oo1, p=o.ooo, respectively). Conclusions. OSDI scores revealed significantly lesser symptoms in polyquad preserved travoprost when compared to BAK preserved travoprost. The OSDI scores in polyquad group were also comparable to the control group. Hence, for long term glaucoma management polyquad containing travoprost should be preferred over the BAK preserved travoprost.

Effects of sustained daily latanoprost application on anterior chamber anatomy and physiology in mice

Latanoprost is a common glaucoma medication. Here, we study longitudinal effects of sustained latanoprost treatment on intraocular pressure (IOP) in C57BL/6J mice, as well as two potential side-effects, changes in iris pigmentation and central corneal thickness (CCT). Male C57BL/6J mice were treated daily for 16 weeks with latanoprost. Control mice were treated on the same schedule with the preservative used with latanoprost, benzalkonium chloride (BAK), or handled, without ocular treatments. IOP and CCT were studied at pre-treatment, 2 "early" time points, and 2 "late" time points; slit-lamp analysis performed at a late time point; and expression of corneal and iridial candidate genes analyzed at the end of the experiment. Latanoprost lowered IOP short, but not long-term. Sustained application of BAK consistently resulted in significant corneal thinning, whereas sustained treatment with latanoprost resulted in smaller and less consistent changes. Neither treatment affected iris pigmentation, corneal matrix metalloprotease expression or iridial pigment-related genes expression. In summary, latanoprost initially lowered IOP in C57BL/6J mice, but became less effective with sustained treatment, likely due to physiological adaptation. These results identify a new resource for studying changes in responsiveness associated with long-term treatment with latanoprost and highlight detrimental effects of commonly used preservative BAK.

Tear biomarkers in latanoprost and bimatoprost treated eyes

Purpose

Prostaglandin analogues (PGA’s) are the mainstay and first line of treatment in current glaucoma practise. Though latanoprost and bimatoprost are the most commonly used PGA’s with minimal side effects at lower concentrations like bimaotoprost 0.01%, direct comparison of their cytokine/MMP profile in tears has not been evaluated earlier. The study intends to ascribe PGA to the upregulation of MMPs, Cytokines and Chemokines mediating varied pathways to result in side effects of the drugs.

Methods

Tear sample collection was done from outer canthus of 30 eyes of 30 patients (primary open angle glaucoma (n = 26 and n’ = 20), normal tension glaucoma (n = 4 and n’ = 10), in latanoprost (n) 0.005% and bimatoprost (n’) 0.01% group respectively, with a mean age of 62±10.5 years) on >6 months of PGA use using Tear flo^TM Schirmer filter strip. Tear samples from 30 eyes of 30 cataract patients without drug treatment were used as the control. Gelatinolytic activity of MMP-9 and MMP-2 were examined by substrate gelatine zymography MMP-1 and TIMP-1 concentrations from tears samples with PGAs were evaluated by ELISA while cytokine concentration in the eluted tears was evaluated using a convenient bioplex kit assay (Milliplex MAP kit, HCYTMAG-60K-PX41, Millipore, Massachusetts, United States). The mean duration of use of PGA in both groups did not differ significantly (median 1.3 years in bimatoprost and 1.1 years in latanoprost eyes, p = 0.6).

Results

The tear MMP-9 expression was higher in eyes receiving latanoprost while the MMP-2 expression was higher in eyes receiving bimatoprost with MMP1 protein levels being higher in the former. Latanoprost treated eyes had marginally elevated tear cytokines involved in tissue remodelling while bimatoprost eyes showed elevated cytokines regulating allergic pathways.

Conclusion

Differential cytokine and MMP expression indicates differential signalling pathways mediating different cellular effects (evident as clinical and side effects) with the two drugs which can be explored further.