Influence of new treatment modalities on adherence in glaucoma

Prostaglandin-based rAAV-mediated glaucoma gene therapy in Brown Norway rats

Prostaglandin analogs are first-line treatments for open angle glaucoma and while effective at lowering intraocular pressure, they are undermined by patient non-compliance, causing atrophy of the optic nerve and severe visual impairment. Herein, we evaluate the safety and efficacy of a recombinant adeno-associated viral vector-mediated gene therapy aimed at permanently lowering intraocular pressure through de novo biosynthesis of prostaglandin F2α within the anterior chamber. This study demonstrated a dose dependent reduction in intraocular pressure in normotensive Brown Norway rats maintained over 12-months. Crucially, therapy could be temporarily halted through off-type riboswitch activation, reverting intraocular pressure to normal. Longitudinal multimodal imaging, electrophysiology, and post-mortem histology revealed the therapy was well tolerated at low and medium doses, with no major adverse effects to anterior chamber health, offering a promising alternative to current treatment strategies leading to clinically relevant reductions in intraocular pressure without the need for adherence to a daily treatment regimen.

Suprachoroidal injection of polyzwitterion hydrogel for treating glaucoma

Glaucoma is the primary cause of irreversible blindness worldwide. The current treatments are primarily based on drug usage or surgical operation to reduce intraocular pressure (IOP). However, it is expensive and requires patients to insist on taking the medicine for a long time. The suprachoroidal space (SCS) is the space between the choroid and the sclera, which forms part of the uveovortex pathway in the circulation of aqueous humor. So far, it is still challenging to realize the injection of hydrogels into the SCS with long-term duration. In this work, an in situ-forming polyzwitterionic polycarboxybetaine hydrogel is designed and injected to expand SCS to increase the drainage of aqueous humor from the eye via the uveovortex pathway, thus reducing IOP for at least 6 weeks, while commercial hyaluronic acid hydrogel can only last for about 4 weeks. The clinical ophthalmological safety assessment examination shows that the treatment of polyzwitterion hydrogel is well-tolerated that leads to minimal inflammatory reaction, and histopathology assessment demonstrates that the SCS is expanded after injection of the hydrogel. Further analysis of ultrasound biomicroscopy reveals that there is a strong correlation between IOP reduction and SCS expansion. In short, the polyzwitterion hydrogel developed in this work can prolong the period of IOP reduction by expanding SCS, thus treating ocular hypertension and glaucoma without resorting to drugs or regular surgery.

MicroPulse Transscleral Laser Therapy Demonstrates Similar Efficacy with a Superior and More Favorable Safety Profile Compared to Continuous-Wave Transscleral Cyclophotocoagulation

Purpose. The aim of this study was to compare effectiveness and safety of MicroPulse transscleral laser therapy (MP-TLT) using the original MicroPulse P3® device and continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) using the G-Probe® device in glaucoma. Methods. Spherical equivalent, intraocular pressure (IOP), best-corrected visual acuity (BCVA), and number of topical or oral ophthalmic pressure-reducing medications were registered at every time point, up to the last follow-up at 12 months. A complete slit-lamp examination was conducted to record the following complications: corneal edema, persistent ocular hypotony (IOP ≤5 mmHg) on two consecutive follow-up visits, choroidal detachment, phthisis bulbi, sympathetic ophthalmia, cystoid macular edema, or other abnormal ocular findings. Success was defined as IOP between 6 and 21 mmHg and >20% reduction in IOP with or without antiglaucoma medications. Results. 47 eyes underwent MP-TLT and 150 CW-TSCPC. At 12 months, success was achieved in 88.6% in the CW-TSCPC group and 87.5% in the MP-TLT group ( $p$  = 0.883). In the CW-TSCPC group, eyes achieved a 42.4% IOP reduction (from 28.3 ± 12.3 mmHg to 15.3 ± 6.0 mmHg) and a 31.1% reduction (from 22.0 ± 7.2 mmHg to 15.7 ± 4.8 mmHg) in the MP-TLT group. Visual acuity remained primarily unaltered in both groups. Conclusion. MP-TLT was as effective in lowering IOP as CW-TSCPC and achieved comparable success. Additionally, MP-TLT demonstrated consistent and effective outcomes at every time point. The improved safety profile of MP-TLT allows the therapeutic spectrum to be broadened, granting ophthalmologists’ treatment of glaucoma in earlier stages of glaucoma than those typically treated with CW-TSCPC, i.e., early to moderate and to patients with good central-vision.

First and second transscleral cyclophotocoagulation treatments provide similar intraocular pressure-lowering efficacy in patients with refractory glaucoma

Purpose

The aim of this study is to address the safety and effectiveness of a second continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) treatment by comparing its outcome against a first CW-TSCPC treatment in the same patients with refractory glaucoma.

Methods

Twenty-one eyes with either primary or secondary glaucoma received a second CW-TSCPC laser session ≥ 3 months after the first treatment. Intraocular pressure (IOP), best-corrected visual acuity (BCVA), and number of topical or oral ophthalmic pressure-reducing medications were registered at every time point up to the last follow-up at 3 months. A complete slit-lamp examination was conducted to record for complications or other abnormal ocular findings. Success was defined as IOP between 6 and 21 mmHg and > 20% reduction in IOP with or without anti-glaucoma medications.

Results

At 3 months follow-up of the first CW-TSCPC treatment, a 24.8% decrease in IOP was observed, whereas a 45.6% IOP decrease was observed 3 months post the second CW-TSCPC treatment. Visual acuity did not decrease, and no major complications were observed post either treatment within the follow-up period. Time to failure was 79.5 ± 24.6 and 77.1 ± 29.4, respectively (P = 0.955). No serious complications were observed.

Conclusion

A second CW-TSCPC treatment proved to be a safe and effective treatment option when the first CW-TSCPC treatment was insufficient in maintaining the desired IOP level for a prolonged time (mean time between both sessions 6.4 ± 8.0 months).

Comparison of adherence between fixed and unfixed topical combination glaucoma therapies using Japanese healthcare/pharmacy claims database: a retrospective non-interventional cohort study

Background

Adherence to chronic therapies is crucial to prevent the progression of disease, such as glaucoma. However, only a limited number of studies have investigated them using real-world data in Japan. This study aimed to evaluate Japanese patients’ adherence to fixed- and unfixed-combination eye drops as a second-line therapy for glaucoma in real-world practice.

Methods

This retrospective, non-interventional cohort study utilized a commercially available Japanese healthcare database (MinaCare database). Medical/pharmacy claims data were collected from 2011 to 2016. The primary endpoint was adherence to medications, assessed by proportion of days covered (PDC) with medication during a 12-month post-index period. Meanwhile, the secondary endpoints included the persistence rate.

Results

A total of 738 patients were included in this study: 309 and 329 in the fixed- and unfixed-combination cohorts, respectively. Prostaglandin analog (PG)/β-blocker (BB) was most commonly claimed in 241/309 (78.0%) patients in the fixed-combination cohort. In the unfixed-combination cohort, PG and BB were claimed in 130/329 (39.5%) patients, whereas PG and α2-agonist were claimed in 87/329 (26.4%) patients. Patients were more adherent to the fixed-combination than the unfixed-combinations (mean PDCs [SD], 79.1% [32.1] vs. 62.2% [38.0]; P < 0.0001). The proportion of patients with good adherence (PDC ≥ 80%) was also higher in the fixed-combination cohort (69.6%) than in the unfixed-combination cohort (48.6%) (P < 0.0001). During the 12-month post-index period, the persistence rate was higher in the fixed-combination cohort than in the unfixed-combination cohort (47.6% [95% confidence intervals (CI): 41.9–53.0] vs. 24.9% [95% CI: 20.4–29.7], P < 0.0001).

Conclusions

Japanese patients with glaucoma preferred the fixed-combination therapies over the unfixed-combination therapies. Hence, fixed-combination therapies would contribute to the improvement of adherence.

Medical anti-glaucoma therapy: Beyond the drop

Barriers to effective medical therapy are numerous and include difficulties with effective and sustained control of intraocular pressure (IOP) and adherence to prescribed anti-glaucoma drop regimens. In an effort to circumvent these challenges, a number of new anti-glaucoma therapies with sustained effects have emerged. Methods for sustained delivery of prostaglandin analogs are being intensely investigated and many are in human clinical trials. Intracameral devices include the following: Allergan's Durysta^™ Bimatoprost SR, Envisia Therapeutics' ENV515 travoprost implant, Glaukos' iDose^™ , Ocular Therapeutix's OTX-TIC travoprost implant, and Santen's polycaprolactone implant with PGE2-derivative DE-117. Other prostaglandin-based technologies include Allergan's bimatoprost ring (placed in the conjunctival fornix), Ocular Therapeutics' OTX-TP intracanalicular travoprost implant, subconjunctival latanoprost in a liposomal formulation, and the PGE2 derivative PGN 9856-isopropyl ester that is applied to the periorbital skin. Exciting breakthroughs in gene therapy include using viral vectors to correct defective genes such as MYOC or to modulate gonioimplant fibrosis, CRISPR technology to edit MYOC or to alter aquaporin to reduce aqueous humor production, and siRNA technology to silence specific genes. Stem cell technology can repopulate depleted tissues or, in the case of Neurotech's Renexus® NT-501 intravitreal implant, serve as a living drug delivery device that continuously secretes neurotrophic factors. Other unique approaches involve nanotechnology, nasal sprays that deliver drug directly to the optic nerve and noninvasive alternating current stimulation of surviving cells in the optic nerve. Over time these modalities are likely to challenge the preeminent role that drops currently play in the medical treatment of glaucoma in animals.

Influence of Cost of Care and Adherence in Glaucoma Management: An Update

The costs for glaucoma care are rising worldwide. The main reason is the increase of life expectancy and the increasing variety of diagnostic tests and therapeutically options by implants and devices. How can we influence the increase in costs? Does a relationship exist between the rising costs and the behavior of patients especially in regard to adherence of patients to the prescribed therapy? Are there ways to improve adherence? The costs of a disease can be estimated by adding the direct costs and the indirect costs deriving from the disease. Many studies have been looking at the direct costs, for example, the costs of diagnostic tests and treatment modalities. Unfortunately, not many studies investigated the indirect costs, i.e., costs related to the need of a person to accompany the patient during his or her outpatient visits or the costs deriving from loss of work capacity because of the disease itself or the outpatient visits. Adherence or the synonym compliance has been discussed since many years, and it seems that it remains a major problem in the management of many chronic diseases. Despite all efforts to improve adherence, the adherence rate in chronic diseases such as glaucoma or arterial hypertension remains considerably low. One of the main factors in improving adherence is raising patient's awareness of the disease by providing general understanding of their disease. Other important factors are simplified therapeutic regimens, e.g., fixed combination drops, sustained drug release techniques, or new glaucoma surgical procedures with a more favorable risk profile.

Amphiphilic Acrylic Nanoparticles Containing the Poloxamer Star Bayfit® 10WF15 as Ophthalmic Drug Carriers

Topical application of drops containing ocular drugs is the preferred non-invasive route to treat diseases that affect the anterior segment of the eye. However, the formulation of eye drops is a major challenge for pharmacists since the access of drugs to ocular tissues is restricted by several barriers. Acetazolamide (ACZ) is a carbonic anhydrase inhibitor used orally for the treatment of ocular hypertension in glaucoma. However, large ACZ doses are needed which results in systemic side effects. Recently, we synthesized copolymers based on 2-hydroxyethyl methacrylate (HEMA) and a functionalized three-arm poloxamer star (Bayfit-MA). The new material (HEMA/Bayfit-MA) was engineered to be transformed into nanoparticles without the use of surfactants, which represents a significant step forward in developing new ophthalmic drug delivery platforms. Acetazolamide-loaded nanocarriers (ACZ-NPs) were prepared via dialysis (224 ± 19 nm, -17.2 ± 0.4 mV). The in vitro release rate of ACZ was constant over 24 h (cumulative delivery of ACZ: 83.3 ± 8.4%). Following standard specifications, ACZ-NPs were not cytotoxic in vitro in cornea, conjunctiva, and macrophages. In normotensive rabbits, ACZ-NPs generated a significant intraocular pressure reduction compared to a conventional solution of ACZ (16.4% versus 9.6%) with the same dose of the hypotensive drug (20 µg). In comparison to previously reported studies, this formulation reduced intraocular pressure with a lower dose of ACZ. In summary, HEMA:Bayfit-MA nanoparticles may be a promising system for ocular topical treatments, showing an enhanced ocular bioavailability of ACZ after a single instillation on the ocular surface.