Phase 3, Randomized, 20-Month Study of the Efficacy and Safety of Bimatoprost Implant in Patients with Open-Angle Glaucoma and Ocular Hypertension (ARTEMIS 2)

Sustained Release Therapies with the Prostaglandin Analogues Intracameral Implants

The travoprost intracameral implant was recently approved by the US Food and Drug Administration for sustained release medical treatment of open-angle glaucoma in the USA. The approval represents a substantial and progressive step forward in the area of sustained-release glaucoma therapy. Topical intraocular pressure-lowering medications for the treatment of glaucoma are faced with a host of challenges for long-term and usually lifelong care. A changing paradigm in glaucoma management involves first-line interventions with laser modalities, micro-invasive surgeries, and sustained-release treatment platforms. Future needs in the area of sustained-release therapy include a non-prostaglandin drug delivery platform and longer-term treatments that do not require surgical reintervention.

Cystoid macular edema occurring after intracameral bimatoprost implantation

PURPOSE

This case report aims to report the development of cystoid macular edema (CME) unilaterally following the administration of bimatoprost implant (Durysta) injections in both eyes for the treatment of primary open-angle glaucoma (POAG).

OBSERVATIONS

An 84-year-old female patient, previously diagnosed with POAG, underwent bimatoprost implant (Durysta) injections in both eyes, spaced one month apart. Subsequently, the patient experienced a gradual decline in visual acuity in her left eye attributed to the development of CME. The condition resolved following a treatment regimen involving topical dexamethasone and nepafenac.

CONCLUSION

The use of bimatoprost implant may lead to the occurrence of CME. Ophthalmologists must vigilantly monitor patients post-implantation, especially if they exhibit visual symptoms or have risk factors for a CME.

Bimatoprost SR for Glaucoma Therapy Implanted at the Slit-Lamp in a Real-World Setting

Purpose

To characterize clinical outcomes following a single administration of bimatoprost SR in eyes with glaucoma in a real-world setting implanted at the slit-lamp.

Setting

Tertiary care Glaucoma practice, Glaucoma Associates of Texas, Dallas, Texas.

Design

Retrospective interventional case series.

Methods

Data were analyzed from consecutive patients receiving a single bimatoprost SR implant from the time of its approval to the time of data collection. All eyes were implanted at the slit-lamp. Eyes with less than 1 month of follow-up were excluded. The primary outcome was median time to next intraocular pressure (IOP)-lowering intervention. Mean IOP and medication use, and changes from baseline, were also assessed through 12 months of follow-up.

Results

Overall 129 eyes of 81 patients were analyzed. Following bimatoprost SR administration (replacing a topical prostaglandin analogue [PGA] in most eyes), the median survival time without any further IOP-lowering interventions was between 6-9 months. Mean IOP remained unchanged from baseline at month 1 (consistent with switch from topical to intracameral PGA therapy) and began to rise at month 3. At month 12, 40.5% of eyes (52 eyes) remained intervention-free, mean medication reduction was 0.5 medications per eye, and 27.8% of eyes (36 eyes) were medication-free. Adverse events were uncommon and most were transient and resolved with or without intervention.

Conclusion

This real-world analysis of bimatoprost SR use for glaucoma therapy complements Phase 3 study findings and demonstrates that the implant can safely provide medication reduction through 6 months in most eyes and through 12 months in almost 40% of eyes.

Corneal endothelial safety profile in minimally invasive glaucoma surgery

PURPOSE

To compare 5-year corneal endothelial safety of 3 minimally invasive glaucoma surgery (MIGS) devices (iStent inject , Hydrus Microstent, CyPass Micro-Stent).

SETTING

U.S. multicenter trials.

DESIGN

Post hoc 5-year analysis from prospective randomized single-masked pivotal trials.

METHODS

Mild to moderate open-angle glaucoma subjects received a MIGS implant with phacoemulsification (implant + phaco) or phaco alone (control). In addition, 5-year end points comparing the implant and control groups included proportion of eyes with significant endothelial cell loss (ECL) (>30% or ≥30% vs baseline) and mean endothelial cell density (ECD).

RESULTS

Comparable proportions of eyes in the iStent inject + phaco and control groups had significant 60-month ECL (9.4% vs 6.3%, respectively, diff: 3.2%, 95% CI, -5.0% to 11.3%, P = .77). Hydrus (20.8% vs 10.6%, diff: 10.2%, 95% CI, 3.2% to 17.2%, P = .01) and CyPass (27.2% vs 10.0%, diff: 17.2%, 95% CI, 5.6% to 28.7%, P = .02) had more eyes with ECL vs controls (iStent inject 1.49X, Hydrus 1.96X, CyPass 2.72X vs controls). Mean ECD over 60 months for iStent inject was indistinguishable vs control, whereas greater ECL was observed primarily 3 months postoperative (Hydrus) or accelerated after 2 years (CyPass). No iStent inject or Hydrus subjects developed persistent corneal edema, whereas 7 CyPass-implanted eyes developed ECL-related complications.

CONCLUSIONS

Through 5 years postoperative, there were no differences in proportion of eyes with significant ECL or mean ECD between the iStent inject and control groups. There was greater 5-year ECL and lower ECD in the Hydrus and CyPass groups vs controls. The Hydrus ECL rate mirrored control after 3 months; the CyPass ECL rate accelerated vs control.

Travoprost Intracameral Implant for Open-Angle Glaucoma or Ocular Hypertension: 12-Month Results of a Randomized, Double-Masked Trial

INTRODUCTION

This prospective, multicenter, randomized, double-masked pivotal phase 3 trial evaluated the efficacy and safety of the travoprost intracameral SE-implant (slow-eluting implant, the intended commercial product) and FE-implant (fast-eluting implant, included primarily for masking purposes) compared to twice-daily (BID) timolol ophthalmic solution, 0.5% in patients with open-angle glaucoma (OAG) or ocular hypertension (OHT).

METHODS

The trial enrolled adult patients with OAG or OHT with an unmedicated mean diurnal intraocular pressure (IOP) of ≥ 21 and unmedicated IOP ≤ 36 mmHg at each diurnal timepoint (8 A.M., 10 A.M., and 4 P.M.) at baseline. The eligible eye of each patient was administered an SE-implant, an FE-implant or had a sham administration procedure. Patients who received an implant were provided placebo eye drops to be administered BID and patients who had the sham procedure were provided timolol eye drops to be administered BID. The primary efficacy endpoint, for which the study was powered, was mean change from baseline IOP at 8 A.M. and 10 A.M. at day 10, week 6, and month 3. Non-inferiority was achieved if the upper 95% confidence interval (CI) on the difference in IOP change from baseline (implant minus timolol) was < 1.5 mmHg at all six timepoints and < 1 mmHg at three or more timepoints. The key secondary endpoint was mean change from baseline IOP at 8 A.M. and 10 A.M. at month 12. Non-inferiority at month 12 was achieved if the upper 95% CI was < 1.5 mmHg at both timepoints. Safety outcomes included treatment-emergent adverse events (TEAEs) and ophthalmic assessments.

RESULTS

A total of 590 patients were enrolled at 45 sites and randomized to one of three treatment groups: 197 SE-implant (the intended commercial product), 200 FE-implant, and 193 timolol. The SE-implant was non-inferior to timolol eye drops in IOP lowering over the first 3 months, and was also non-inferior to timolol at months 6, 9, and 12. The FE-implant was non-inferior to timolol over the first 3 months, and also at months 6 and 9. Of those patients who were on glaucoma medication at screening, a significantly greater proportion of patients in the SE- and FE-implant groups (83.5% and 78.7%, respectively) compared to the timolol group (23.9%) were on fewer topical glaucoma medications at month 12 compared to screening (P < 0.0001, chi-square test). TEAEs, mostly mild, were reported in the study eyes of 39.5% of patients in the SE-implant group, 34.0% of patients in the FE-implant group and 20.1% of patients in the timolol group.

CONCLUSIONS

The SE-travoprost intracameral implant demonstrated non-inferiority to timolol over 12 months whereas the FE-implant demonstrated non-inferiority over 9 months. Both implant models were safe and effective in IOP lowering in patients with OAG or OHT.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03519386.

Currently available prostanoids for the treatment of glaucoma and ocular hypertension: A review

Recent advancements in prostaglandin analogs (PGAs) have reinforced their role in managing intraocular pressure (IOP). Latanoprost excels in 24-h IOP control, while various PGAs offer similar effectiveness and side effects, generic PGAs perform as well as branded ones, and a notable IOP rise observed upon PGA discontinuation. Formulations with or without preservatives show comparable IOP reduction and adherence, often surpassing benzalkonium chloride (BAK)-preserved options. Emergent PGAs, such as latanoprostene bunod, fixed-dose netarsudil combined with latanoprost, and omidenepag Isopropyl, offer enhanced or non-inferior IOP reduction. The bimatoprost implant introduces a novel administration method with effective IOP reduction. These developments underscore ongoing progress in PGA-focused ophthalmological research. This article offers a comprehensive review of available prostanoid analogs and explores new developments.

Ocular drug delivery systems: glaucoma patient perceptions from a German university hospital eye clinic

PURPOSE

This study aimed to report on glaucoma patients' beliefs and illness perceptions and to investigate their opinion on ocular drug delivery devices (ODD).

METHODS

We performed a cross-sectional study in a large tertiary-referral outpatient glaucoma clinic, with 102 patients. Validated anonymized questionnaires were used. We investigated the awareness and acceptance regarding ODD (contact lenses (CLs), punctal plugs (PPs), subconjunctival implants, anterior chamber (AC) injections, and drug-emitting stents) and looked at factors that could influence a patient's decision for having an ODD.

RESULTS

Sixty-three patients (61.8%) confirmed they would rather have ODD than keep their eye-drops (38.2%). The most important factors influencing their decision were effectiveness and long-lasting effect. A large proportion of patients reported a preference for CLs (48.0%), PPs (52.9%), or drug-emitting stents (44.1%). When comparing patients who preferred ODD (group-1) versus eye-drops (group-2), significantly more patients in group-1 were worried (p < 0.001) or felt disrupted (p < 0.001) by their use of eye-drops. A significantly greater share of patients in group-1 showed acceptance towards CLs (60.3% vs. 38.5%; p = 0.032), AC injections (38.1% vs. 12.8%, p = 0.006), or drug-emitting stents (54% vs. 28.2%, p = 0.023), whilst there were no significant differences regarding the acceptance of PPs (p = 0.363) or subconjunctival implants (p = 0.058).

CONCLUSION

ODD for the treatment of glaucoma were broadly deemed acceptable by patients in this study. Effectiveness and long-lasting effect were the most important factors for a decision towards having an ODD. The majority of patients who preferred an ODD felt severely affected by their disease and were negatively influenced by their glaucoma medication intake.

Real-World Study of the Effectiveness and Safety of Intracameral Bimatoprost Implant in a Clinical Setting in the United States

Purpose

A sustained-release, biodegradable, intracameral 10-µg bimatoprost implant (Durysta) is approved for single administration per eye to lower intraocular pressure (IOP) in open-angle glaucoma (OAG) and ocular hypertension (OHT). The purpose of this study was to evaluate the IOP-lowering effectiveness and safety of a single implant administration per eye in patients with OAG or OHT in a real-world clinical setting.

Methods

This was a retrospective, single-site study involving 105 consecutive adult patients with OAG or OHT treated with the bimatoprost implant in 1 or both eyes in routine clinical practice. Available medical records of the patients for 12 months or longer after the initial implant administration were reviewed, and data including IOP, IOP-lowering medication and procedure use, and safety outcomes were collected and analyzed. The analysis used ranges of follow-up because of the real-world setting.

Results

The study included 197 eyes (85.3% diagnosed with OAG, 94.9% pseudophakic, and 83.8% with angle grade 4). IOP reduction was observed through 1 year after the bimatoprost implant administration. Mean IOP was 16.6 mmHg at baseline and 13.3 mmHg at 11-13 months, with the mean number of topical IOP-lowering medications used reduced from 1.4 at baseline to 0.2 at 11-13 months. IOP and IOP-lowering medication use were similarly reduced in eyes treated with both selective laser trabeculoplasty (SLT) and bimatoprost implant (including 66 eyes with their last SLT before implant administration and 28 eyes with their last SLT after implant administration). There were no cases of treatment-emergent corneal edema after bimatoprost implant administration, and no eye required implant removal.

Conclusion

A single bimatoprost implant administration safely and effectively reduced IOP for up to 1 year and decreased the need for topical IOP-lowering medications in eyes with OAG or OHT with or without previous or subsequent SLT.

Qualitative Development of the Allergan Satisfaction with Treatment Experience Questionnaire (ASTEQ) Instrument, a Patient-Reported Outcome Measure in Glaucoma and Ocular Hypertension

INTRODUCTION

Sustained-release intraocular implants provide a therapeutic option for open-angle glaucoma (OAG) and ocular hypertension (OHT) patients who are non-compliant with eyedrops. Currently, there are no published patient-reported outcome (PRO) measures that assess treatment satisfaction with intraocular implants. To address this gap, a new PRO instrument, the Allergan Satisfaction with Treatment Experience Questionnaire (ASTEQ), has been developed in accordance with Food and Drug Administration guidance.

METHODS

Qualitative research interviews were conducted among patients with OAG/OHT who had received three intraocular injections of a sustained-release bimatoprost (10 or 15 µg) implant within the clinical trial setting. A preliminary conceptual framework capturing treatment satisfaction concepts in glaucoma, as identified from the literature, was used to develop a semi-structured interview guide. A concept elicitation (CE) interview to identify aspects of the glaucoma treatment experience pertinent to intraocular implants provided content for a draft instrument. A cognitive debriefing (CD) interview to test the instrument's interpretability, relevance, and validity informed its subsequent refinement. Interview analysis followed a grounded theory approach to identify data patterns and relationships.

RESULTS

CE interviews (n = 19) indicated that participants' main considerations in rating satisfaction with implant treatment were physical comfort during preparation for the implant and implant administration, anxiety about the procedure, frequency of implant administration, possible side effects, convenience and accessibility of the implant, relationship with the clinician, and lifestyle fit. Draft ASTEQ revision based on CD interviews (n = 20) and readability tests yielded a nine-item ASTEQ instrument comprising satisfaction with overall implant experience and frequency of administration, occurrence/bother of immediate and long-term side effects, worry about implant administration and possible risks/side effects, and physical discomfort during preparation for the implant and implant administration.

CONCLUSION

The ASTEQ instrument has demonstrated content validity in patients with OAG/OHT treated with a sustained-release bimatoprost implant. Further research is necessary to evaluate its psychometric properties.

Efficacy and Safety of the Travoprost Intraocular Implant in Reducing Topical IOP-Lowering Medication Burden in Patients with Open-Angle Glaucoma or Ocular Hypertension

PURPOSE

A randomized, double-masked, multicenter, phase 2 trial to evaluate the long-term safety and efficacy of travoprost intraocular implant, an extended-release drug delivery system designed to provide uninterrupted sustained intraocular pressure (IOP)-lowering therapy, thereby reducing patient treatment burden and improving adherence with IOP-lowering medication.

METHODS

Patients with open-angle glaucoma or ocular hypertension were administered a fast-eluting implant (FE implant, n = 51) and received twice-daily (BID) placebo eye drops, a slow-eluting (SE implant, n = 54) and received BID placebo eye drops, or underwent a sham surgical procedure and received BID timolol 0.5% (n = 49). IOP was measured at baseline, day 1-2, day 10, week 4, week 6, month 3, and every 3 months thereafter through 36 months. Efficacy was evaluated by mean change from 8:00 AM unmedicated baseline IOP through month 36, and the percentage of patients receiving the same or fewer topical IOP-lowering medications as at screening (pre-study). Safety was evaluated by adverse events and ophthalmic parameters.

RESULTS

Clinically and statistically relevant IOP-lowering treatment effects were observed through month 36 after a single administration of the travoprost implant compared with BID timolol with mean IOP reductions ranging from 7.6 to 8.8 mmHg for the FE implant group, from 7.3 to 8.0 mmHg for the SE implant group, and from 7.3 to 7.9 for the timolol group at the 8:00 AM timepoint (P < 0.0001 for all treatment groups at all visits). At months 12, 24, and 36, a greater percentage of FE and SE implant patients versus timolol patients were well controlled on the same or fewer topical IOP-lowering medications compared with screening with 63 and 69% for the FE and SE implants groups, respectively, versus 45% for the timolol group at month 36. The safety profile of the implant was favorable; there were no dislodgements, no explantations, no adverse events of conjunctival hyperemia or periorbital fat atrophy, no discontinuations due to study eye adverse events, nor any serious adverse events in the study eye. Comparable changes from baseline in corneal endothelial cell counts were observed in the three treatment groups over the 36 months.

CONCLUSION

The travoprost intraocular implant demonstrated robust IOP-lowering and substantially reduced topical IOP-lowering medication burden for up to 36 months following a single administration, while maintaining a favorable safety profile. The travoprost intraocular implant promises to be a meaningful addition to the interventional glaucoma armamentarium by addressing the key shortcomings of topical IOP-lowering medications, including low adherence and topical side effects while controlling IOP for up to 36 months.

TRIAL REGISTRY

ClinicalTrials.gov identifier NCT02754596 registered 28 April 2016.

Single Administration of Bimatoprost Implant: Effects on 24-Hour Intraocular Pressure and 1-Year Outcomes

PURPOSE

To evaluate the effects of a single bimatoprost implant administration on 24-hour intraocular pressure (IOP) lowering at 8 weeks, and 1-year IOP-lowering efficacy and safety outcomes.

DESIGN

Multicenter, open-label, 12-month, phase 3b study (NCT04285580).

PARTICIPANTS

Adults with open-angle glaucoma or ocular hypertension.

METHODS

Participants (n = 31) received 10-μg bimatoprost implant in the study eye on day 1; IOP (sitting and/or supine) was measured with pneumatonometry every 2 hours throughout a 24-hour period at baseline and week 8. IOP was measured by Goldmann applanation tonometry (GAT) at hour 0 (8 am ± 1 hour) at baseline, weeks 8 and 16, and months 6, 9, and 12.

MAIN OUTCOME MEASURES

The primary endpoint was the week-8 hour-matched change from baseline in habitual position IOP over 24 hours assessed with pneumatonometry. Hour 0 IOP change from baseline measured with GAT in study eyes that received no additional (rescue) IOP-lowering treatment, treatment-emergent adverse events (TEAEs), and central corneal endothelial cell density (CECD) were evaluated through 12 months.

RESULTS

The mean (standard deviation [SD]) baseline IOP at hour 0 was 24.2 (2.70) mmHg and 25.3 (7.15) mmHg by GAT and pneumatonometry, respectively. Pneumatonometer measurements of IOP taken over 24 hours at week 8 with the participant in habitual position (sitting from 8 am to 10 pm, supine from 12 am to 6 am) showed consistent IOP lowering through the day and night and reduced fluctuation in IOP. The range in IOP measurements over 24 hours was reduced from baseline by a mean (SD) of -1.6 (2.98) mmHg. All 31 bimatoprost implant-treated participants completed the 12-month study; 23 (74%) required no rescue IOP-lowering treatment. The mean (SD) IOP reduction from baseline at month 12 in nonrescued eyes was -4.3 (3.35) mmHg. The most common TEAE was conjunctival hyperemia (incidence 35.5%, 11/31). No implant-treated eye had a ≥ 15% loss in CECD from baseline.

CONCLUSIONS

A single intracameral administration of the bimatoprost implant lowered IOP in the habitual position consistently throughout the day and night at week 8. The majority of participants continued to have reduced IOP for 1 year without additional therapy. The 1-year safety profile was favorable.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Phase 3, Randomized Study Comparing Intracameral Bimatoprost Implant 15 µg and Selective Laser Trabeculectomy in Patients with Open-Angle Glaucoma or Ocular Hypertension

Purpose

We evaluate the safety and intraocular pressure (IOP)-lowering effect of 15-µg bimatoprost implant (higher dose than the currently approved product) compared with selective laser trabeculoplasty (SLT) in patients with open-angle glaucoma or ocular hypertension.

Methods

Randomized, phase 3, 12-month, multicenter, paired-eye, patient- and efficacy evaluator-masked noninferiority study. Patients with inadequate IOP control were randomized to receive 360° SLT (day 1) or up to 3 administrations of 15-µg bimatoprost implant (day 4, weeks 16 and 32) in the primary eye and the alternative treatment in the contralateral eye. The primary endpoint was IOP change from baseline at weeks 4, 12, and 24.

Results

At weeks 4, 12, and 24, mean IOP change from baseline ranged from -7.01 to -6.65 mm Hg in implant-treated eyes (N=138) and -6.45 to -6.26 mm Hg in SLT-treated eyes (N=138). Differences in IOP change from baseline ranged from -0.70 to -0.25 mm Hg favoring implant; the upper limit of the 95% confidence interval of the difference (implant minus SLT) was <1.0 mm Hg at all 3 visits. The probability of requiring no additional (rescue) IOP-lowering treatment in implant-treated versus SLT-treated eyes was 93.6% versus 86.5% at day 180 and 74.6% versus 77.1% at day 360. Corneal endothelial cell loss was more common in implant-treated eyes and typically occurred after repeated implant administration.

Conclusion

Bimatoprost implant 15 µg met prespecified criteria for statistical and clinical noninferiority to SLT in lowering IOP, and after 1, 2, or 3 administrations, demonstrated a duration of IOP lowering similar to SLT. Bimatoprost implant 15 µg was associated with corneal adverse events in some patients, especially after repeated administrations at a fixed interval, and has been discontinued from development. A lower dose strength of implant (bimatoprost implant 10 µg, Durysta) is US Food and Drug Administration-approved for single administration.

New Devices in Glaucoma

Glaucoma remains a leading cause of blindness globally. Minimally invasive treatment techniques are rapidly expanding the availability of therapeutic options for glaucoma. These include devices aimed at enhancing outflow through the subconjunctival space, Schlemm's canal, and suprachoroidal space, sustained-release drug delivery devices, and extraocular devices aiming to reduce glaucomatous progression through other novel means. In this review, we provide an overview of several novel devices either newly available or in development for the medical and surgical management of glaucoma. Further studies are required to determine the long-term efficacy of these devices and how they will integrate into the current landscape of glaucoma management.

Short-Term Outcomes of Bimatoprost Sustained-Release Intracameral Implant in Glaucoma

PRCIS

This retrospective study found a statistically significant reduction in mean intraocular pressure (IOP) and the number of medications after intracameral Bimatoprost sustained release (SR) injection in patients with glaucoma. A history of selective laser trabeculoplasty (SLT) did not impact treatment outcomes.

PURPOSE

To determine outcomes of Bimatoprost SR on IOP and the number of topical IOP-lowering medications in patients with glaucoma. A secondary objective was to determine the outcomes of Bimatoprost SR in patients with a prior history of SLT.

METHODS

Retrospective case series. One hundred eighteen eyes from 84 patients that received Bimatoprost SR by 6 glaucoma specialists at Wills Eye Hospital from March 2020 to September 2021 were examined. The intervention was a single injection of intracameral Bimatoprost SR. The main outcome measures included IOP and the number of medications.

RESULTS

The most recent mean follow-up time for all eyes was 27.8 ± 18.6 weeks. The mean posttreatment IOP at the most recent follow-up of 16.6 ± 5.3 mm Hg was significantly lower than the mean under-therapy pretreatment IOP of 18.5 ± 5.7 mm Hg for all eyes ( P < 0.01). The mean posttreatment number of medications at the most recent follow-up of 1.3 ± 1.3 decreased compared with the number of pretreatment medications of 2.1 ± 1.4 for all eyes ( P < 0.01). Analysis of multilevel models controlling for demographic variables demonstrated a statistically significant reduction in IOP and number of medications posttreatment ( P < 0.01). A prior history of SLT (n = 54) had no impact on treatment for both IOP and the number of medications ( P > 0.1 for both).

CONCLUSIONS

Intracameral Bimatoprost SR reduced IOP and decreased the number of medications. Prior history of SLT did not impact Bimatoprost SR treatment outcomes.

Biodegradable Polymer-Based Drug-Delivery Systems for Ocular Diseases

Ocular drug delivery is a challenging field due to the unique anatomical and physiological barriers of the eye. Biodegradable polymers have emerged as promising tools for efficient and controlled drug delivery in ocular diseases. This review provides an overview of biodegradable polymer-based drug-delivery systems for ocular diseases with emphasis on the potential for biodegradable polymers to overcome the limitations of conventional methods, allowing for sustained drug release, improved bioavailability, and targeted therapy. Natural and synthetic polymers are both discussed, highlighting their biodegradability and biocompatibility. Various formulation strategies, such as nanoparticles, hydrogels, and microemulsions, among others, are investigated, detailing preparation methods, drug encapsulation, and clinical applications. The focus is on anterior and posterior segment drug delivery, covering glaucoma, corneal disorders, ocular inflammation, retinal diseases, age-related macular degeneration, and diabetic retinopathy. Safety considerations, such as biocompatibility evaluations, in vivo toxicity studies, and clinical safety, are addressed. Future perspectives encompass advancements, regulatory considerations, and clinical translation challenges. In conclusion, biodegradable polymers offer potential for efficient and targeted ocular drug delivery, improving therapeutic outcomes while reducing side effects. Further research is needed to optimize formulation strategies and address regulatory requirements for successful clinical implementation.

Recently Approved Drugs for Lowering and Controlling Intraocular Pressure to Reduce Vision Loss in Ocular Hypertensive and Glaucoma Patients

Serious vision loss occurs in patients affected by chronically raised intraocular pressure (IOP), a characteristic of many forms of glaucoma where damage to the optic nerve components causes progressive degeneration of retinal and brain neurons involved in visual perception. While many risk factors abound and have been validated for this glaucomatous optic neuropathy (GON), the major one is ocular hypertension (OHT), which results from the accumulation of excess aqueous humor (AQH) fluid in the anterior chamber of the eye. Millions around the world suffer from this asymptomatic and progressive degenerative eye disease. Since clinical evidence has revealed a strong correlation between the reduction in elevated IOP/OHT and GON progression, many drugs, devices, and surgical techniques have been developed to lower and control IOP. The constant quest for new pharmaceuticals and other modalities with superior therapeutic indices has recently yielded health authority-approved novel drugs with unique pharmacological signatures and mechanism(s) of action and AQH drainage microdevices for effectively and durably treating OHT. A unique nitric oxide-donating conjugate of latanoprost, an FP-receptor prostaglandin (PG; latanoprostene bunod), new rho kinase inhibitors (ripasudil; netarsudil), a novel non-PG EP2-receptor-selective agonist (omidenepag isopropyl), and a form of FP-receptor PG in a slow-release intracameral implant (Durysta) represent the additions to the pharmaceutical toolchest to mitigate the ravages of OHT. Despite these advances, early diagnosis of OHT and glaucoma still lags behind and would benefit from further concerted effort and attention.

Emerging glaucoma treatments: are we seeing an improvement in adherence?

Introduction

Non-adherence to glaucoma medication and poor follow-up is a global health concern.

Areas covered

Glaucoma remains one of the largest causes of irreversible blindness worldwide. Traditional treatment guidelines suggest topical eye drop medication as first line therapy followed by addition of supplementary medications before proceeding to more invasive glaucoma surgeries. Unfortunately, poor glaucoma self-management remains high, leading to disease progression and blindness. Recent advancements in the field of pharmacotherapies, surgeries, and behavioral approaches have taken aim at increasing support for glaucoma self-management. We review the current and emerging approaches towards glaucoma management, with the exception of bleb-based surgical approaches, to investigate if they have had an impact on adherence. Literature searches were conducted via MEDLINE (PubMed), Embase (Elsevier), Cochrane Library (Wiley), and Preprints from January 1st, 2018, to January 26th, 2023.

Expert opinion

The ability to offer patients a multitude of choices enables patients to tailor their glaucoma treatment to their values and lifestyle. Offering personalized patient education and coaching to support chronic glaucoma self-management would better enable patient engagement in whichever treatment path is chosen. Currently, literature regarding the impact of these new advancements on treatment engagement is lacking; this field is ripe for additional intervention and assessment.

Proposed Mechanism of Long-Term Intraocular Pressure Lowering With the Bimatoprost Implant

Purpose

The purpose of this study was to evaluate the effects of pharmacologically relevant bimatoprost and bimatoprost free acid (BFA) concentrations on matrix metalloproteinase (MMP) gene expression in cells from human aqueous outflow tissues.

Methods

MMP gene expression by human trabecular meshwork (TM), scleral fibroblast (SF), and ciliary muscle (CM) cells exposed to 10 to 1000 µM bimatoprost or 0.1 to 10 µM BFA (intraocular concentrations after intracameral bimatoprost implant and topical bimatoprost dosing, respectively) was measured by polymerase chain reaction array.

Results

Bimatoprost dose-dependently upregulated MMP1 and MMP14 mRNA in all cell types and MMP10 and MMP11 mRNA in TM and CM cells; in TM cells from normal eyes, mean MMP1 mRNA levels were 62.9-fold control levels at 1000 µM bimatoprost. BFA upregulated MMP1 mRNA only in TM and SF cells, to two- to three-fold control levels. The largest changes in extracellular matrix (ECM)-related gene expression by TM cells derived from normal (n = 6) or primary open-angle glaucoma (n = 3) eyes occurred with 1000 µM bimatoprost (statistically significant, ≥50% change for 9-11 of 84 genes on the array, versus 1 gene with 10 µM BFA).

Conclusions

Bimatoprost and BFA had differential effects on MMP/ECM gene expression. Dramatic upregulation in MMP1 and downregulation of fibronectin, which occurred only with bimatoprost at high concentrations observed in bimatoprost implant-treated eyes, may promote sustained outflow tissue remodeling and long-term intraocular pressure reduction beyond the duration of intraocular drug bioavailability. Variability in bimatoprost-stimulated MMP upregulation among cell strains from different donors may help explain differential long-term responses of patients to bimatoprost implant.

Bimatoprost Implant Biodegradation in the Phase 3, Randomized, 20-Month ARTEMIS Studies

Purpose: To evaluate the time course of biodegradation of an intracameral, biodegradable, sustained-release bimatoprost implant that lowers intraocular pressure without the need for daily eye drops. Methods: In 2 identically designed, randomized, phase 3 clinical trials, adults with open-angle glaucoma or ocular hypertension and open iridocorneal angles inferiorly in the study eye were administered 10- or 15-μg bimatoprost implant (day 1 and weeks 16 and 32) or twice-daily topical timolol 0.5%. Implants were assessed on gonioscopy throughout the studies. Investigators reported whether implants were visible, estimated the size of visible implants relative to their initial size at implantation, and reported the implant location. Data for 10-μg implant placed on day 1 were pooled from both studies for analysis. Results: A total of 372 patients received the 10-μg bimatoprost implant. The degree of implant biodegradation at each follow-up time point was variable among patients. The implant frequently swelled during the initial phase of biodegradation from 6 to 28 weeks. Accelerated biodegradation occurred between 31 and 52 weeks, resulting in 82% of implants absent or ≤25% of initial size by 52 weeks. By month 20, 95% of implants had biodegraded to absent or ≤25% of initial size. The implant was predominantly located inferiorly in the iridocorneal angle. Conclusions: Bimatoprost implant biodegradation in phase 3 studies showed some degree of variability among patients. Clinically significant implant biodegradation was observed in the majority of patients by 12 months. Clinical studies are in progress to further understand implant biodegradation and the ideal timing for implant re-administration. ClinicalTrials.gov NCT02247804; ClinicalTrials.gov NCT02250651.

Devices and Treatments to Address Low Adherence in Glaucoma Patients: A Narrative Review

Poor adherence to topical glaucoma medications has been linked to worse visual field outcomes in glaucoma patients. Therefore, identifying and overcoming the adherence barriers are expected to slow down the progression of disease. The most common barriers to adherence, in addition to the lack of knowledge, include forgetfulness, side effects of medications, difficulties with drop instillation and low self-efficacy. Symptoms and signs of ocular surface disease, which importantly reduce patients' quality of life, are decreased by using preservative-free topical medications. Sustained drug delivery systems using different vehicles seem promising for relieving the burden of drop administration. Currently, only the bimatoprost sustained-release intracameral implant is available for clinical use and single administration. In the era of digitalization, smart drug delivery-connected devices may aid adherence and, by sharing data with care providers, improve monitoring and adjusting treatment. Selective laser trabeculoplasty as first-line treatment delays the need for drops, whereas minimally invasive glaucoma procedures with and without devices combined with cataract surgery increase the likelihood of patients with early-to-moderate glaucoma to remain drop free or reduce the number of drops needed to control intraocular pressure. The aim of this narrative review is to present and discuss devices and treatments that may improve adherence by reducing the need for drops and side effects of medications and aiding in glaucoma monitoring. For the future, there is a need for studies focusing on clinically important outcomes, quality of life and the cost of intervention with longer post-interventional follow up.

Single Administration of Intracameral Bimatoprost Implant 10 µg in Patients with Open-Angle Glaucoma or Ocular Hypertension

Introduction

This study evaluated the intraocular pressure (IOP)-lowering efficacy and safety of a single intracameral administration of bimatoprost implant 10 µg in adults with open-angle glaucoma or ocular hypertension.

Methods

Two identically designed, randomized, 20-month, parallel-group, phase 3 clinical trials (one study eye/patient) compared three administrations of 10- or 15-µg bimatoprost implant (day 1, weeks 16 and 32) with twice-daily topical timolol maleate 0.5%. An open-label, 24-month, phase 1/2 clinical trial compared one or two implants administered in the study eye with once-daily topical bimatoprost 0.03% in the fellow eye. Separate analyses of the pooled phase 3 and phase 1/2 study datasets evaluated outcomes in the 10-µg bimatoprost implant and comparator treatment arms after a single implant administration, up to the time of implant re-administration or rescue with IOP-lowering medication.

Results

In the phase 3 studies, 10-µg bimatoprost implant single administration demonstrated IOP reductions (hour 0) of 4.9–7.0 mmHg through week 15 from a mean (standard deviation, SD) baseline IOP of 24.5 (2.6) mmHg (n = 374); IOP in the topical timolol BID group was reduced by 6.0–6.3 mmHg from a mean (SD) baseline IOP of 24.5 (2.6) mmHg (n = 373). In the phase 1/2 study (n = 21), median time to use of additional IOP-lowering treatment (Kaplan–Meier analysis) was 273 days (approximately 9 months), and 5 of 21 enrolled patients (23.8%) required no additional IOP-lowering treatment up to 24 months after single administration. In each study, after a single implant administration there were no reports of corneal edema, corneal endothelial cell loss, or corneal touch, and no patients had 20% or greater loss in corneal endothelial cell density.

Conclusions

Bimatoprost implant single administration lowers IOP and has a favorable safety profile. Additional studies are needed to further evaluate the duration of effect and factors predicting long-term IOP lowering after a single implant administration.

Trial registration numbers

ClinicalTrials.gov NCT02247804, NCT02250651, and NCT01157364.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-022-00527-6.

Intraocular Pressure-Lowering Efficacy of a Sustained-Release Bimatoprost Implant in Dog Eyes Pretreated with Selective Laser Trabeculoplasty

Purpose:

To assess the intraocular pressure (IOP)-lowering effect of a biodegradable bimatoprost implant following selective laser trabeculoplasty (SLT) in a canine model.

Methods:

Unilateral SLT was performed in 11 normotensive, treatment-naive beagle dogs. IOP was measured at baseline (pre-SLT) and weekly post-SLT (≤10 weeks). After IOP returned to baseline or at 10 weeks (whichever occurred first), a sustained-release bimatoprost implant was administered bilaterally in the anterior chamber of each animal. IOP was measured weekly for 4 weeks and then every 2 weeks up to week 42.

Results:

The main outcomes included the IOP change (%) from baseline, calculated in both eyes in the overall population, SLT responder subgroup (defined by peak IOP reduction from baseline ≥3 mmHg or ≥15% for >1 week post-SLT), and SLT nonresponder subgroup (defined by peak IOP reduction from baseline <3 mmHg or <15%). The bimatoprost implant lowered IOP similarly in both the SLT-treated and fellow SLT-naive eyes. Following bimatoprost implant administration, the mean (standard deviation [SD]) peak IOP reduction from baseline was 34.4% (8.5%) in SLT-treated eyes and 35.7% (5.9%) in fellow SLT-naive eyes. The bimatoprost implant lowered IOP comparably (P > 0.17) in eyes that responded to SLT (mean [SD] peak IOP reduction, 34.6% [10.7%]; n = 6) and those that did not (mean [SD] peak IOP reduction, 34.1% [6.1%]; n = 5).

Conclusion:

The bimatoprost implant effectively lowered IOP in eyes pretreated with SLT, regardless of response to SLT. The current data suggest that eyes previously treated with SLT can still benefit from the intracameral bimatoprost implant.

Current situation and progress of drugs for reducing intraocular pressure

Glaucoma, the most common cause of irreversible blindness worldwide, usually causes characteristic optic nerve damage. Pathological intraocular pressure (IOP) elevation is a major risk factor. Drug reduction of IOP is the preferred treatment for clinicians because it can delay the progression of disease. However, the traditional IOP-lowering drugs currently used by patients may be poorly tolerated. Therefore, in recent years, some new drugs have been put into clinical application or in clinical phase I–III studies. They have a better IOP-lowering effect and fewer adverse reactions. Because glaucoma is a chronic disease, drugs need to be administered continuously for a long time. For patients, good compliance and high drug bioavailability have a positive effect on the prognosis of the disease. Therefore, clinicians and scientists have developed drug delivery systems to solve this complex problem. In addition, natural compounds and dietary supplements have a good effect of reducing IOP, and they can also protect the optic nerve through antioxidant action. We summarize the current traditional drugs, new drugs, sustained-release drug delivery systems, and complementary drugs and outline the mechanism of action and clinical effects of these drugs on glaucoma and their recent advances.