Cross-linked actin networks (CLANs) in glaucoma.

One of the major causes of decreased vision, irreversible vision loss and blindness worldwide is glaucoma. Increased intraocular pressure (IOP) is a major risk factor associated with glaucoma and its molecular mechanisms are not fully understood. The trabecular meshwork (TM) is the primary site of injury in glaucoma, and its dysfunction results in elevated IOP. The glaucomatous TM has increased extracellular matrix deposition as well as cytoskeletal rearrangements referred to as cross-linked actin networks (CLANs) that consist of dome like structures consisting of hubs and spokes. CLANs are thought to play a role in increased aqueous humor outflow resistance and increased IOP by creating stiffer TM cells and tissue. CLANs are inducible by glucocorticoids (GCs) and TGFß2 in confluent TM cells and TM tissues. The signaling pathways of these induction agents give insight into the possible mechanisms of CLAN formation, but to date, the mechanism of CLANs regulation by these pathways has yet to be determined. Understanding the role CLANs play in IOP elevation and their mechanisms of induction and regulation may lead to novel treatment options to help prevent or intervene in glaucomatous damage to the trabecular meshwork.

Qualitative Research to Understand the Patient Experience and Evaluate Content Validity of the Chronic Ocular Pain Questionnaire (COP-Q).

INTRODUCTION: Chronic ocular surface pain (COSP) is described as a persistent, moderate-to-severe pain at the ocular surface lasting more than 3 months. Symptoms of COSP have a significant impact on patients' vision-dependent activities of daily living (ADL) and distal health-related quality of life (HRQoL). To adequately capture patient perspectives in clinical trials, patient-reported outcome (PRO) measures must demonstrate sufficient evidence of content validity in the target population. This study aimed to explore the patient experience of living with COSP and evaluate content validity of the newly developed Chronic Ocular Pain Questionnaire (COP-Q) for use in COSP clinical trials. METHODS: Qualitative, combined concept elicitation (CE) and cognitive debriefing (CD) interviews were conducted with 24 patients experiencing COSP symptoms in the USA. Interviews were supplemented with real-time data collection via a daily diary app task in a subset of patients (n = 15) to explore the day-to-day patient experience. Three healthcare professionals (HCPs) from the USA, Canada, and France were also interviewed to provide a clinical perspective. CE results were used to further inform development of a conceptual model and to refine PRO items/response options. CD interviews assessed relevance and understanding of the COP-Q. Interviews were conducted across multiple rounds to allow item modifications and subsequent testing. RESULTS: Eye pain, eye itch, burning sensation, eye dryness, eye irritation, foreign body sensation, eye fatigue, and eye grittiness were the most frequently reported symptoms impacting vision-dependent ADL (e.g., reading, using digital devices, driving) and wider HRQoL (e.g., emotional wellbeing, social functioning, work). COP-Q instructions, items, and response scales were understood, and concepts were considered relevant. Feedback supported modifications to instruction/item wording and confirmed the most appropriate recall periods. CONCLUSIONS: Findings support content validity of the COP-Q for use in COSP populations. Ongoing research to evaluate psychometric validity of the COP-Q will support future use of the instrument in clinical trial efficacy endpoints.

Possible Strategies to Mitigate Placebo or Vehicle Response in Dry Eye Disease Trials: A Narrative Review.

Many candidate drugs for dry eye disease (DED) have been assessed over the years in pursuit of demonstrating efficacy in both signs and symptoms. However, patients with DED have very limited treatment options for management of both signs and symptoms of DED. There are several potential reasons behind this including the placebo or vehicle response, which is a frequent issue observed in DED trials. A high magnitude of vehicle response interferes with the estimation of a drug's treatment effect and may lead to failure of a clinical trial. To address these concerns, Tear Film and Ocular Surface Society International Dry Eye Workshop II taskforce has recommended a few study design strategies to minimize vehicle response observed in DED trials. This review briefly describes the factors that lead to placebo/vehicle response in DED trials and focuses on the aspects of clinical trial design that can be improved to mitigate vehicle response. In addition, it presents the observations from a recent ECF843 phase 2b study, wherein the study design approach consisted of a vehicle run-in phase, withdrawal phase, and masked treatment transition, and led to consistent data for DED signs and symptoms and reduced vehicle response post randomization.

Characterization of a spontaneously immortalized bovine trabecular meshwork cell line.

Trabecular meshwork (TM) cells have widely been used as an in vitro model for glaucoma research. However, primary TM cells suffer the disadvantages of limited cell numbers and slow rates of proliferation. We discovered a spontaneously transformed bovine TM (BTM) cell line, BTM-28T. This cell line proliferated rapidly in low-glucose culture medium but also demonstrated contact inhibition in high-glucose culture medium. BTM-28T cells expressed key TM cell markers including α-smooth muscle actin (α-SMA), laminin and collagen IV (col IV). Also, 100 nM dexamethasone (DEX) enhanced the formation of cross-linked actin networks (CLANs) in confluent BTM-28T cell cultures. Transforming growth factor beta 2 (TGFß2) induced the expression of fibronectin (FN), plasminogen activator inhibitor-1 (PAI-1), and connective tissue growth factor (CTGF) in our cell cultures. This cell line will be helpful to better understand the aqueous humor outflow pathway as related to the pathophysiology of glaucoma.

Patient perspectives on dry eye disease and chronic ocular surface pain: Insights from a virtual community-moderated dialogue.

PURPOSE: To understand patients' perspectives on living with dry eye disease (DED), and on the unmet needs in DED and chronic ocular surface pain (COSP) management. METHODS: A moderated, structured discussion with patients with ocular surface diseases and healthcare professionals (HCPs) was conducted using a virtual platform to capture patients' journey with DED, their opinion on unmet needs, and design and conduct of clinical trials in DED and COSP. RESULTS: Nine participants, including four patient representatives from patient organisations, one ophthalmologist and one optometrist participated in the discussion. Patients had DED of varying severity and aetiology; three patients had Sjögren's. Over 4 weeks, 785 posts were entered on the platform. Prior to diagnosis, patients rarely associated their symptoms with DED. Convenience and symptomatic relief scored higher than treating the disease. Patients expressed the need for plain language information and dialogue with knowledgeable and sensitive HCPs. Online forums and social media were suggested as key recruitment resources, whereas convenience and safety concerns were highlighted as main barriers to enrolment. The need for the inclusion of outcome measures that have a real impact on patients' experience of their condition was highlighted. Both target product profiles were received positively by participants, highlighting the twice-daily dosing regimen and convenience of the products. Participants acknowledged the value of digital tools and suggested the need to feel valued post-trial. CONCLUSIONS: This moderated dialogue provided actionable insights on the unmet needs in DED and useful inputs for consideration when designing future clinical trials for DED and COSP.

TGFß2 Induces the Formation of Cross-Linked Actin Networks (CLANs) in Human Trabecular Meshwork Cells Through the Smad and Non-Smad Dependent Pathways.

Purpose: Increased intraocular pressure results from increased aqueous humor (AH) outflow resistance at the trabecular meshwork (TM) due to pathologic changes including the formation of cross-linked actin networks (CLANs). Transforming growth factor ß2 (TGFß2) is elevated in the AH and TM of primary open angle glaucoma (POAG) patients and induces POAG-associated TM changes, including CLANs. We determined the role of individual TGFß2 signaling pathways in CLAN formation. Methods: Cultured nonglaucomatous human TM (NTM) cells were treated with control or TGFß2, with or without the inhibitors of TGFß receptor, Smad3, c-Jun N-terminal kinases (JNK), extracellular signal regulated kinase (ERK), P38, or Rho-associated protein kinase (ROCK). NTM cells were cotreated with TGFß2 plus inhibitors for 10 days or pretreated with TGFß2 for 10 days followed by 1-hour inhibitor treatment. NTM cells were immunostained with phalloidin-Alexa-488 and 4',6-diamidino-2-phenylindole (DAPI). Data were analyzed using 1-way ANOVA and Dunnett's post hoc test. Results: TGFß2 significantly induced CLAN formation (n = 6 to 12, P < 0.05), which was completely inhibited by TGFß receptor, Smad3, and ERK inhibitors, as well as completely or partially inhibited by JNK, P38, and ROCK inhibitors, depending on cell strains. One-hour exposure to ROCK inhibitor completely resolved formed CLANs (P < 0.05), whereas TGFß receptor, Smad3 inhibitor, and ERK inhibitors resulted in partial or complete resolution. The JNK and P38 inhibitors showed partial or no resolution. Among these inhibitors, the ROCK inhibitor was the most disruptive to the actin stress fibers, whereas ERK inhibition showed the least disruption. Conclusions: TGFß2-induced CLANs in NTM cells were prevented and resolved using various pathway inhibitors. Apart from CLAN inhibition, some of these inhibitors also had different effects on actin stress fibers.

Ocular surface disease in patients with glaucoma or ocular hypertension treated with either BAK-preserved latanoprost or BAK-free travoprost.

PURPOSE: The preservative benzalkonium chloride (BAK) may adversely affect ocular surface health. This study evaluated symptoms of ocular surface disease (OSD) in patients previously treated with a BAK-preserved therapy to lower their intraocular pressure, who either continued that therapy or switched to a BAK-free therapy. METHODS: Eligible adult patients with ocular hypertension or open-angle glaucoma that had been controlled with BAK-preserved latanoprost 0.005% monotherapy (Xalatan ®) for at least one month and had a score of ≥ 13 (0 = none, 100 = most severe) on the Ocular Surface Disease Index (OSDI) questionnaire were entered into this prospective, double-masked, randomized, active-controlled, multicenter trial. By random assignment, patients either continued with BAK-preserved latanoprost 0.005% or transitioned to BAK-free travoprost 0.004% (Travatan Z ® ophthalmic solution). OSDI scores were assessed again after six and 12 weeks. RESULTS: For the 678 evaluable patients, mean change in OSDI score from baseline to week 12 favored the travoprost 0.004% BAK-free group, but was not statistically different between groups (P = 0.10). When patients with mild OSD at baseline were assessed after 12 weeks, the mean OSDI score was significantly lower (P = 0.04) in the BAK-free travoprost 0.004% group (score = 11.6 ± 10.8 units) than in the BAK-preserved latanoprost 0.005% group (score = 14.4 ± 11.9 units), and a significantly larger percentage (P < 0.01) improved to normal OSDI scores in the BAK-free travoprost 0.004% group (62.9% of group) than in the BAK-preserved latanoprost 0.005% group (47.0% of group). Patients pretreated with BAK-preserved latanoprost 0.005% for >24 months were significantly more likely (P = 0.03) to improve to a normal OSDI score after 12 weeks if they were switched to BAK-free travoprost 0.004% (47.9% of group) than if they remained on BAK-preserved latanoprost 0.005% (33.9% of group). CONCLUSIONS: Switching from BAK-preserved latanoprost 0.005% to BAK-free travoprost 0.004% yielded significant improvements in symptoms of OSD in patients with glaucoma or ocular hypertension.