AG-920 (Articaine) Ophthalmic Solution: A Masked, Active-Controlled Evaluation of Its Local Anesthetic Efficacy and Safety in Pediatric Patients.

Purpose: The safety and efficacy of a novel topical ocular anesthetic (AG-920 sterile ophthalmic solution, 8%) was previously evaluated in adults. For both clinical and regulatory purposes, this new agent was evaluated in children. Methods: This was a Phase 3, randomized, active-controlled, single-masked, parallel-group design study in healthy pediatric subjects performed at a private practice retina clinic in the United States. The safety and anesthetic efficacy of AG-920 was compared with proparacaine hydrochloride ophthalmic solution 0.5% in 60 children undergoing ophthalmic examinations. The primary efficacy endpoint was whether the investigator was able to perform the eye examination. Results: In all subjects in each treatment group, the investigator was able to perform the eye examination without additional local anesthetic. There were no adverse events reported in this study. In both the study eye and fellow eye, there were no notable changes after dosing, and both treatment groups were similar. All external eye exams in all subjects in both treatment groups were normal. Conclusions: In this pediatric population aged 7 months to >11 years, AG-920 was therapeutically equivalent to marketed proparacaine with respect to having an ophthalmic examination performed without needing additional local anesthetic. Further, AG-920 was well tolerated, and there were no clinically significant safety findings.

Two Randomized, Double-masked, Placebo-controlled Studies of the Local Anesthetic Effect of Articaine Ophthalmic Solution.

Background: We wanted to develop a new topical ocular anesthetic with good bioavailability in anterior segment tissues. Given concerns about contamination and sterility in multi-dose products, we selected a unit-dose, nonpreserved presentation of AG-920 (articaine ophthalmic solution) in blow-fill-seal containers (similar to currently marketed pharmacological therapies for dry eye disease). Methods: Consistent with US Food and Drug Administration guidance, two pivotal, Phase 3, randomized, placebo-controlled, double-masked, parallel design studies conducted at two US private practices in 240 healthy subjects. A single dose of AG-920 or identical looking placebo into one (study) eye (2 drops 30 s apart). Subjects underwent a conjunctival pinch procedure and assessment of the pain associated with the pinch. The main outcome measure was the proportion of subjects with rating of "No pain at 5 minutes". Results: AG-920 provided a rapid onset of local anesthesia (less than one minute) with clinically and statistically significantly greater effect in AG-920 (68% and 83%) than placebo (3% and 18% for Study 1 and Study 2, respectively, P<0.0001). The most frequent adverse event was instillation site pain (27% vs 3%) followed by conjunctival hyperemia (probably related to the pinch, 9% vs 10%) in the AG-920 and placebo groups, respectively. Conclusion: AG-920 was found to be have a rapid onset and useful duration of local anesthesia with no major safety issues, and may be useful for the eye-care professional. Registered with clinicaltrials.gov as NCT04513652 and NCT04829344.

Early Nonclinical and Clinical Development of AG-920, a Repurposed Topical Ocular Anesthetic.

Purpose: To evaluate the preclinical effects, and preclinical and clinical ocular and systemic pharmacokinetics of a new topical, non-preserved ocular anesthetic, AG-920 (articaine ophthalmic solution). Methods: Five studies: one in vitro melanin binding study; three studies in rabbits receiving an ocular dose of AG-920 evaluating corneal sensitivity, ocular tolerability, and systemic exposure to articaine and its inactive metabolite, articainic acid; and one clinical study in 14 healthy adult volunteers receiving an ocular dose of AG-920, with blood samples over 24 h. A liquid chromatography with tandem mass spectrometry (LC-MS-MS) method was used to detect both parent and metabolite with a lower limit of quantitation (LLOQ) of 0.1 and 0.2 ng/mL, respectively. Results: Melanin binding of articaine was up to 7.4%. A decrease in corneal sensitivity was noted for 20 min post-treatment in all active groups, and returned to baseline by 60 min post-dose. No dose-response relationship was observed. Concentrations of articaine in ocular matrices generally peaked early and then decreased over time. Both parent and metabolite were observed in blood at early time points. There were no ocular safety issues with AG-920. Conclusions: These early stage development studies showed that AG-920 was well tolerated in the standard preclinical models and did not cause any toxicity. AG-920 ophthalmic solution elicited a rapid onset and potentially clinically useful duration of corneal anesthesia. The studies supported the clinical evaluation of the 8% strength. Registered with clinicaltrials.gov as NCT04759339.

Endoscopic Cyclophotocoagulation and Pars Plana Ablation (ECP-plus) to Treat Refractory Glaucoma.

PURPOSE: To report clinical outcomes after pars plana endoscopic cyclophotocoagulation of the ciliary processes and pars plana (ECP-plus), a novel treatment for refractory glaucoma. DESIGN: Retrospective, noncomparative interventional case series. SETTING: multicenter tertiary referral academic and clinical practice. STUDY POPULATION: fifty-three eyes of 53 consecutive subjects undergoing ECP-plus who had uncontrolled intraocular pressure (IOP) despite prior glaucoma surgeries and maximally tolerated medical therapy. OBSERVATION PROCEDURE: retrospective analysis of clinical data after ECP-plus and pars plana vitrectomy. MAIN OUTCOME MEASURES: primary outcome was IOP at 6 and 12 months. Secondary outcomes were number of glaucoma medications and postoperative complications. RESULTS: Diagnoses were primary open-angle glaucoma (32%), chronic angle-closure glaucoma (26%), and secondary open-angle glaucoma (OAG, 42%); 50/53 of subjects had 6 months' and 28/53 had 12 months' follow-up data. Preoperative IOP was 27.9±7.5 mm Hg (mean±SD). Postoperative IOP at 6 mo was 10.2±5.6 and at 12 mo was 10.7±5.2 lower than preoperative levels (all P<0.0001). Cumulative treatment success was 81% at 6 mo and 78% at 12 mo. Number of medications fell from 3.4±1.2 pretreatment to 0.8±1.0 at 1 to 6 mo and 0.7±1.2 at 12 mo postoperatively (all P<0.0001). Complications in the initial postoperative period (<3 mo) were hypotony (3/53, 6%), fibrinous uveitis (2/53, 4%), and cystoid macular edema without hypotony (CME; 4/53, 6%). Complications beyond 6 mo occurred in 8/50 (16%) subjects as hypotony (4/50, 8%), choroidal detachment (4/50, 3 with IOP<5 and 1 with IOP≥5; 8%), CME without hypotony (3/50, 6%), and failed corneal graft (1/50, 2%). CONCLUSIONS: The mean IOP was lowered by at least 61% after ECP-plus and IOP lowering was sustained over the follow-up period. Fewer glaucoma medications were needed. Complication rates were comparable with or slightly higher than anterior endoscopic cyclophotocoagulation and acceptable given the refractory nature of disease being treated.

Endoscopic ophthalmic surgery of the anterior segment.

We summarize the uses of anterior segment endoscopic techniques and the basic science and technology of endoscopic cyclophotocoagulation (ECP) as compared with transscleral cyclophotocoagulation. This is followed by an analysis of patient selection for ECP, a description of surgical techniques, and clinical results. In addition, the ophthalmic endoscope has other uses in anterior segment surgeries. We discuss the techniques for these endoscope-assisted surgeries.

Injection parameters affect cell viability and implant volumes in automated cell delivery for the brain.

The technique of central nervous system cell implantation can affect the outcome of preclinical or clinical studies. Our goal was to evaluate the impact of various injection parameters that may be of consequence during the delivery of solute-suspended cells. These parameters included (1) the type and concentration of cells used for implantation, (2) the rate at which cells are injected (flow rate), (3) the acceleration of the delivery device, (4) the period of time between cell loading and injection into the CNS (delay), and (5) the length and gauge of the needle used to deliver the cells. Neural progenitor cells (NPCs) and bone marrow stromal cells (BMSCs) were injected an automated device. These parameters were assessed in relation to their effect on the volume of cells injected and cell viability. Longer and thinner cannulae and higher cell concentrations were detrimental for cell delivery. Devices and techniques that optimize these parameters should be of benefit.

Manual vs automated delivery of cells for transplantation: accuracy, reproducibility, and impact on viability.

BACKGROUND: Cellular transplantation holds promise for the management of a variety of neurological disorders. However, there is great variability in cell type, preparation methods, and implantation technique, which are crucial to clinical outcomes. OBJECTIVE: We compared manual injection with automated injection using a prototype device to determine the possible value of a mechanized delivery system. METHODS: Neural progenitor cells and bone marrow stromal cells were injected using manual or automated methods. Consistency of injection volumes and cell number and viability were evaluated immediately or 1 day after injection. RESULTS: When cells were delivered as a series of 3 manual injections from the same syringe, the variation in fluid volume was greater than for single manual injections. Automated delivery of a series of 3 injections resulted in a lower variability in the amount of delivery than manual injection for both cell lines (1.2%-2.6% coefficient of variability for automated delivery vs 4.3%-24.0% for manual delivery). The amount delivered from injection 1 to injection 3 increased significantly with manual injections, whereas the amount injected did not vary over the 3 injections for the automated unit. Cell viability 1 day after injection was typically 30% to 40% of the value immediately after injection for the bone marrow stromal cells and 30% to 70% for the neural progenitor cells. There were no significant differences in viability attributed to the method of injection. CONCLUSION: The automated delivery device led to enhanced consistency of volumetric cell delivery but did not improve cell viability in the methods tested. Automated techniques could be useful in standardizing reproducible procedures for cell transplantation and improve both preclinical and clinical research.

Cellular transplantation for the nervous system: impact of time after preparation on cell viability and survival.

OBJECT: Cell transplantation has shown promise for the treatment of various neurological disorders, but the factors that influence cell survival and integration following transplantation are poorly understood. In fact, little is known regarding how simple but potentially critical variables, including the method of cellular preparation and administration, might affect transplant success. The goal of the present study was to determine the impact of time between tissue preparation and implantation on cellular viability. Time can vary with cell preparation, delivery to the operating room, and surgical technique. This study was also designed to evaluate the sensitivity of various methods of assessing implant viability. METHODS: Cell lines of neural progenitor cells and bone marrow stromal cells were generated from healthy adult mice. On the day of experimentation, the cells were collected, suspended in a balanced salt solution, and sequentially assessed for viability for up to 3.5 hours based on their appearance under phase-contrast microscopy, their ability to retain a fluorescent dye, and their attachment to a cultivation surface for 24 hours. RESULTS: When viability was measured based on the ability of cells to retain a fluorescent dye, there was a decrease in viability of 10-15% each hour. Based on the ability of the cells to attach to a culture surface and grow for 24 hours, viability decreased more rapidly at approximately 20% per hour. In addition, only about one-third of the cells judged viable based on phase-contrast microscopy or acute dye retention were found to be viable based on plating, and only 10% of the cells initially judged as viable were still capable of survival after 3 hours in suspension. CONCLUSIONS: The authors' results indicate that that there can be significant losses in viability between preparation and implantation and that more sophisticated methods of evaluation, such as the ability of cells to attach to a substrate and grow, may be required to detect decreases in viability. The time between preparation and implantation will be an important factor in clinical trial design.