Role of prostaglandins and specific place in therapy of bimatoprost in the treatment of elevated intraocular pressure and ocular hypertension: A closer look at the agonist properties of bimatoprost and the prostamides

Therapeutic Potential of Cannabinoids in Glaucoma

Glaucoma is a leading cause of irreversible blindness worldwide. To date, intraocular pressure (IOP) is the only modifiable risk factor in glaucoma treatment, but even in treated patients, the disease can progress. Cannabinoids, which have been known to lower IOP since the 1970s, have been shown to have beneficial effects in glaucoma patients beyond their IOP-lowering properties. In addition to the classical cannabinoid receptors CB1 and CB2, knowledge of non-classical cannabinoid receptors and the endocannabinoid system has increased in recent years. In particular, the CB2 receptor has been shown to mediate anti-inflammatory, anti-apoptotic, and neuroprotective properties, which may represent a promising therapeutic target for neuroprotection in glaucoma patients. Due to their vasodilatory effects, cannabinoids improve blood flow to the optic nerve head, which may suggest a vasoprotective potential and counteract the altered blood flow observed in glaucoma patients. The aim of this review was to assess the available evidence on the effects and therapeutic potential of cannabinoids in glaucoma patients. The pharmacological mechanisms underlying the effects of cannabinoids on IOP, neuroprotection, and ocular hemodynamics have been discussed.

Prostaglandin F2α Agonists Negatively Modulate the Size of 3D Organoids from Primary Human Orbital Fibroblasts

Purpose

To elucidate the molecular etiology of deepening of the upper eyelid sulcus (DUES) induced by prostaglandin (PG) analogs, a three-dimensional (3D) tissue culture system was employed using human orbital fibroblasts (HOFs).

Methods

During adipogenesis, changes in HOF 3D organoid sizes, as well as their lipids stained by BODIPY and expression of the extracellular matrix (ECM) by immunolabeling and/or quantitative PCR, were studied in the presence or absence of either 100-nM bimatoprost acid or 100-nM prostaglandin F2α.

Results

The size of the 3D organoids increased remarkably during adipogenesis, but such increases were significantly inhibited by the presence of PG analogs. Staining intensities by BODIPY and mRNA expression of peroxisome proliferator-activated receptor gamma were significantly increased upon adipogenesis but were not influenced by the presence of PG analogs. Unique changes in ECM expression observed with or without adipogenic differentiation were significantly modified by the presence of PG analogs.

Conclusions

Our present study indicates that PG analogs have the potential to modulate the ECM network within HOF 3D organoids. Thus, a 3D tissue culture system may be a suitable strategy for understanding the disease etiology of DUES.

Bimatoprost 0.03% for the Treatment of Eyebrow Hypotrichosis

BACKGROUND

Eyebrow loss may have substantial negative functional and social consequences.

OBJECTIVE

Evaluate the safety and efficacy of bimatoprost 0.03% in subjects with eyebrow hypotrichosis.

METHODS

This multicenter, double-masked study randomized adult females or males with eyebrow hypotrichosis to receive bimatoprost 0.03% twice (BID) or once daily (QD) or vehicle BID for 7 months. Primary endpoint was overall eyebrow fullness at Month 7. Secondary endpoints included eyebrow fullness (mm²), darkness (intensity units), and subject satisfaction with treatment. Safety was also assessed.

RESULTS

At Month 7, the proportion of subjects with improvement was significantly higher in bimatoprost groups versus vehicle (both, p < .001). Improvements occurred in both bimatoprost groups versus vehicle after Month 1 and continued through follow-up; eyebrow fullness and darkness improved as early as Months 2 and 1, respectively (both, p < .001). Greater satisfaction was reported with bimatoprost versus vehicle at Month 2 and all subsequent time points. Overall, 38.1%, 42.4%, and 35.5% of subjects in the bimatoprost BID, QD, and vehicle groups, respectively, experienced ≥1 treatment-emergent adverse event (TEAE). Most frequent TEAEs were similar across groups. No skin or iris hyperpigmentation or conjunctival hyperemia occurred.

CONCLUSION

Bimatoprost 0.03% BID and QD is safe, well tolerated, and effective for eyebrow hypotrichosis.

Efficacy and Safety of Switching Latanoprost Monotherapy to Bimatoprost Monotherapy or Combination of Brinzolamide and Latanoprost

Purpose:

To prospectively assess the efficacy and safety of switching to bimatoprost monotherapy or brinzolamide and latanoprost combination therapy in patients who had been receiving latanoprost monotherapy.

Methods:

A prospective, open-label study was conducted. Patients with primary open-angle glaucoma or ocular hypertension who had been receiving latanoprost monotherapy for three months or more were enrolled. Bimatoprost was substituted for latanoprost in one eye (BIM group), and brinzolamide was added to the latanoprost in the other eye (BRZ group) simultaneously. The patients underwent examinations at 6 weeks (visit 1) and 12 weeks (visit 2) after changing therapies. Subsequently, the treatments were returned to latanoprost monotherapy. The patients underwent another examination 6 weeks (visit 3) after the return to latanoprost. The parameters examined were intraocular pressure (IOP), conjunctival hyperemia, and corneal epithelial damage.

Results:

Twenty-six patients (13 men and 13 women) completed the protocol. Both groups showed a significant IOP reduction at visits 1 and 2 compared with the baseline, with a similar magnitude (BIM group: P = 0.016 at visit 1, P = 0.025 at visit 2, BRZ group: P = 0.0006 at visit 1, P = 0.028 at visit 2). The IOPs at the baseline and on visit 3 were similar in both groups (P = 0.7). The two groups showed no changes in either conjunctival hyperemia or corneal epithelial damage compared with the baseline.

Conclusion:

Bimatoprost monotherapy and brinzolamide adjunctive to latanoprost similarly reduced the IOP, with no additive adverse effects, compared with latanoprost monotherapy.

The Endocannabinoid System as a Therapeutic Target in Glaucoma

Glaucoma is an irreversible blinding eye disease which produces progressive retinal ganglion cell (RGC) loss. Intraocular pressure (IOP) is currently the only modifiable risk factor, and lowering IOP results in reduced risk of progression of the disorder. The endocannabinoid system (ECS) has attracted considerable attention as a potential target for the treatment of glaucoma, largely due to the observed IOP lowering effects seen after administration of exogenous cannabinoids. However, recent evidence has suggested that modulation of the ECS may also be neuroprotective. This paper will review the use of cannabinoids in glaucoma, presenting pertinent information regarding the pathophysiology of glaucoma and how alterations in cannabinoid signalling may contribute to glaucoma pathology. Additionally, the mechanisms and potential for the use of cannabinoids and other novel agents that target the endocannabinoid system in the treatment of glaucoma will be discussed.

Long-term safety and efficacy of bimatoprost solution 0·03% application to the eyelid margin for the treatment of idiopathic and chemotherapy-induced eyelash hypotrichosis: a randomized controlled trial

Background

Bimatoprost ophthalmic solution 0·03% is approved in several countries for the treatment of eyelash hypotrichosis. Previous trials were limited to 4 months of treatment and primarily idiopathic hypotrichosis.

Objectives

To evaluate the long‐term safety and efficacy of bimatoprost in patients with idiopathic or chemotherapy‐induced hypotrichosis.

Methods

This multicentre, double‐masked, randomized, parallel‐group study included two 6‐month treatment periods [treatment period 1 (TP1) and treatment period 2 (TP2)]. Patients with idiopathic hypotrichosis were randomized to three treatment groups: (i) bimatoprost (TP1 and TP2); (ii) bimatoprost (TP1) and vehicle (TP2); and (iii) vehicle (TP1) and bimatoprost (TP2). Patients with chemotherapy‐induced hypotrichosis were randomized to two treatment groups: (i) bimatoprost or vehicle (TP1) and (ii) bimatoprost (TP2). Primary end point was a composite of at least a one‐grade improvement in investigator‐assessed Global Eyelash Assessment and at least a three‐point improvement in patient‐reported Eyelash Satisfaction Questionnaire Domain 2 at month 4. Secondary measures included digitally assessed eyelash characteristics.

Results

The primary efficacy end point was met in both populations (idiopathic responder rate was 40·2% for bimatoprost vs. 6·8% for vehicle; postchemotherapy responder rate was 37·5% for bimatoprost vs. 18·2% for vehicle). Efficacy by month 6 was maintained (idiopathic) or enhanced (postchemotherapy) at 12 months. Treatment effects were maintained for approximately 2 months but markedly diminished 4–6 months following treatment cessation in patients with idiopathic hypotrichosis. No drug‐related serious adverse events were reported.

Conclusions

Daily treatment with bimatoprost ophthalmic solution 0·03% for 1 year was effective and well tolerated in patients with idiopathic and chemotherapy‐induced hypotrichosis.

What's already known about this topic?

The safety and efficacy of bimatoprost ophthalmic solution 0·03% have been previously established for idiopathic hypotrichosis in studies lasting up to 4 months.

What does this study add?

Very little has been reported on eyelash loss and regrowth after chemotherapy, and there is currently no standard prevention or treatment for chemotherapy‐induced hypotrichosis of the eyelashes.

We provide long‐term (up to 12 months) safety and efficacy data for treatment with bimatoprost ophthalmic solution 0·03% in chemotherapy‐induced and idiopathic hypotrichosis.

Secondary neuroprotective effects of hypotensive drugs and potential mechanisms of action

Primary open-angle glaucoma, a long-term degenerative ocular neuropathy, remains a significant cause of vision impairment worldwide. While many risk factors have been correlated with increased risk for primary open-angle glaucoma, intraocular pressure (IOP) remains the only modifiable risk factor and primary therapeutic target. Pharmacologic therapies are administered topically; these include α(2)-agonists, β-antagonists, prostaglandin analogs and carbonic anhydrase inhibitors. Some of these topical medications exhibit secondary neuroprotective effects independent of their effect on IOP. This review covers the possible mechanisms of neuroprotection stimulated by drugs currently marketed for the lowering of IOP, based on known literature. While the neuroprotective properties of many glaucoma pharmaceuticals are promising from an experimental standpoint, key challenges for the development of new clinical practices include unknown systemic side effects, limited methods of drug delivery to the retina and optic nerve, and development of extended-release formulations.

Bimatoprost 0.03% preservative-free ophthalmic solution versus bimatoprost 0.03% ophthalmic solution (Lumigan) for glaucoma or ocular hypertension: a 12-week, randomised, double-masked trial

Background/Aim

To evaluate efficacy and safety of bimatoprost 0.03% preservative-free (PF) ophthalmic solution versus bimatoprost 0.03% (Lumigan) ophthalmic solution for glaucoma or ocular hypertension.

Methods

In this double-masked, parallel-group study, patients were randomised to bimatoprost PF or bimatoprost for 12 weeks. The primary analysis for non-inferiority was change from baseline in worse eye intraocular pressure (IOP) in the per-protocol population at week 12. For equivalence, it was average eye IOP in the intent-to-treat population at each time point at weeks 2, 6 and 12.

Results

597 patients were randomised (bimatoprost PF, n=302 and bimatoprost, n=295). The 95% CI upper limit for worse eye IOP change from baseline was <1.5 mm Hg at each week 12 time point, meeting prespecified non-inferiority criteria. The 95% CI upper limit for the treatment difference for average IOP was 0.69 mm Hg and the lower limit was −0.50 mm Hg at all follow-up time points (hours 0, 2 and 8 at weeks 2, 6 and 12), meeting equivalence criteria. Both treatments showed decreases in mean average eye IOP at all follow-up time points (p<0.001), were safe and well tolerated.

Conclusions

Bimatoprost PF is non-inferior and equivalent to bimatoprost in its ability to reduce IOP-lowering with a safety profile similar to bimatoprost.

N-Acylethanolamines and related compounds: aspects of metabolism and functions

N-Acylethanolamines (NAE) are fatty acid derivates that are linked with an ethanolamine group via an amide bond. NAE can be characterized as lipid mediators in the plant and animal kingdoms owing to the diverse functions throughout the eukaryotic domain. The functions of NAE have been widely investigated in animal tissues in part due to their abilities to interact with the cannabinoid receptors, vanilloid receptors or peroxisome proliferator activated receptors. However, the interest of studying the functions of these lipids in plants is progressively becoming more apparent. The number of publications about the functions related to NAE and to structural analogs (homoserine lactone and alkamides) is greatly increasing, showing the importance of these lipids in various plant physiological processes. This review sheds light on their role in different processes such as seedling development, plant pathogen interaction, phospholipase D alpha inhibition and senescence of cut flowers, and underlines the interaction between NAE and NAE-related molecules with plant hormone signaling. The different metabolic pathways promoting the synthesis and degradation of NAE are also discussed, in particular the oxygenation of polyunsaturated N-acylethanolamines, which leads to NAE-oxylipins, a new family of bioactive lipids.