Clinically Relevant Activity of the Novel RASP Inhibitor Reproxalap in Allergic Conjunctivitis: The Phase 3 ALLEVIATE Trial

Reproxalap in patients with seasonal allergic conjunctivitis: a systematic review and meta-analysis

INTRODUCTION

Seasonal allergic conjunctivitis (SAC) is a hypersensitivity condition characterized by itching, tearing, and redness. It affects over 20% of the general population with limited therapeutic options. Reproxalap, a novel small-molecule aldehyde trap, has emerged as a potential treatment option for SAC by targeting reactive aldehydes involved in inflammation. In this systematic review and meta-analysis, we assessed the efficacy and safety of Reproxalap in treating SAC.

METHODS

Multiple databases were searched including PubMed, Cochrane Library, Scopus, and Google Scholar, to identify relevant studies. Clinical trials involving patients diagnosed with SAC and treated with Reproxalap (0.25% or 0.5%) were included. The primary outcomes were symptom relief (efficacy) and side effects (safety). Data extraction and risk of bias assessment were performed independently by two reviewers. Meta-analysis was conducted using RevMan 5.4 software.

RESULTS

Five RCTs involving 625 participants were included. Reproxalap significantly reduced ocular itching compared to control groups for both 0.25% (SMD: -0.31, 95% CI: -0.50 to -0.13, P = .001) and 0.5% concentrations (SMD: -0.31, 95% CI: -0.51 to -0.10, P = 0.004). No significant difference was observed between the two doses (SMD: -0.02, 95% CI: -0.23 to 0.19, P = 0.83). Side effects were more frequent in both Reproxalap groups compared to controls, with odds ratios of 35.31 (95% CI: 17.83 to 69.90, P < 0.00001) for 0.25% and 45.64 (95% CI: 18.49 to 112.66, P < 0.00001) for 0.5%. The 0.5% dose had significantly higher odds of side effects compared to the 0.25% dose (OR: 1.66, 95% CI: 1.10 to 2.51, P = 0.02). Heterogeneity was low for all outcomes (I2 = 0%).

CONCLUSION

Reproxalap reduces ocular itching associated with SAC. While both 0.25% and 0.5% concentrations are effective, safe and tolerable. Further research should focus on the long-term benefits and applicability of Reproxalap on diverse populations.

Reversing Signs of Parkinsonism in a Cell Model Using Mitochondria-Targeted Organoiridium Catalysis

We report the application of organoiridium complexes as catalytic agents for the detoxification of biogenic reactive aldehyde species (RASP), which are implicated in the pathogenesis of neurodegenerative disorders. We show that Ir complexes functionalized with phosphonium cations localize selectively in the mitochondria and have better cellular retention compared to that of their parent Ir species. In a cell model for Parkinsonism, the mitochondria-targeted iridium catalysts exhibited superior cell protecting abilities and longer-lasting effects (up to 6 d) than conventional RASP scavengers, which failed to be effective beyond 24 h. Our biological assays indicate that treatment with the Ir compounds led to reduction in reactive oxygen species and aldehyde levels while partially preserving the native mitochondrial membrane potential and NAD+/NADH ratio in 1-methyl-4-phenylpyridinium-inhibited cells. Our work is the first to demonstrate catalytic nonenzymatic detoxification of RASP in living systems.

Novel treatments for dry eye syndrome

Dry eye syndrome (DES) is a prevalent and multifactorial disease that leads to a self-perpetuating cycle of inflammation and damage to the ocular surface. This results in symptoms such as redness, burning, and blurred vision, which can negatively affect a patient's quality of life. While treatments are available to manage DES, they only temporarily relieve symptoms. Furthermore, long-term use of certain medications can cause harm to the ocular surface. Therefore, there is a need for safer and effective treatments for DES. This review highlights the latest advancements in DES therapy, providing valuable insights into ongoing efforts to improve patient outcomes.

[New and future treatment approaches for allergic conjunctivitis]

BACKGROUND

In severe and recurrent ocular allergies conventional ophthalmic drugs can reach their limits, especially in chronic forms. The first novel immunomodulators and biologicals are already in clinical use and could provide relief.

OBJECTIVE

Based on the immunopathophysiological mechanisms of ocular allergies, possible targets for innovative treatment approaches are presented. An overview of promising new and future immunomodulators and biologicals and their modes of action is also given.

MATERIAL AND METHODS

Current reviews on ocular allergies and the treatment of systemic allergic diseases were screened. Case reports on the treatment of ocular allergy using immunomodulators and biologicals were analyzed. The clinical relevance and possible applications are presented.

RESULTS

In chronic forms of ocular allergies, complex ocular surface inflammatory responses mediated via immunoglobulin E (IgE), mast cells, CD4-positive type 2 T‑helper cells and eosinophilic granulocytes are predominant. Cyclosporine A 0.1% eyedrops have been approved in Europe since 2018 for children aged 4 years and older with severe vernal keratoconjunctivitis (VKC). In addition, case reports present promising data on the systemic off-label use of biologicals, such as dupilumab or omalizumab, in refractory VKC or atopic keratoconjunctivitis (AKC).

CONCLUSION

A profound understanding of the immunopathophysiology of ocular allergies is necessary to detect further targets for future immunomodulators and biologicals. Currently, immunomodulatory therapy remains limited to cyclosporine A eyedrops. Other immunomodulatory agents, such as tacrolimus and biologicals can only be used off-label. Further studies on the controlled clinical use of these substances in the treatment of VKC or AKC are underway.

The Phase 3 INVIGORATE Trial of Reproxalap in Patients with Seasonal Allergic Conjunctivitis

Purpose

There is an unmet need for new treatments for allergic conjunctivitis.

Objective

To assess the activity of reproxalap, a novel reactive aldehyde species modulator, in a real-world model of seasonal allergen exposure.

Methods

The INVIGORATE Trial, a prospective, quadruple-masked, vehicle-controlled, crossover, sequence-randomized Phase 3 trial, tested the efficacy of reproxalap in adults with a history of moderate to severe allergic conjunctivitis, ragweed pollen allergy, and allergen chamber-induced ocular itching and redness. Patients were randomly assigned (1:1) to receive 0.25% reproxalap ophthalmic solution or vehicle, followed by a 2-week washout period before crossing over to the other test article. The primary endpoint was ocular itching from 110 to 210 minutes after chamber entry; the key secondary endpoint was ocular redness over the chamber duration (0-4 scales for both endpoints).

Results

Of the 95 randomly assigned patients, 89 completed all visits (reproxalap to vehicle: n = 46; vehicle to reproxalap: n = 43). Primary and key secondary endpoints were met: reproxalap significantly reduced ocular itching (mean [SE]: -0.50 [0.03], p < 0.001) and redness (-0.14 [0.01], p < 0.001) relative to vehicle. Responder analyses confirmed the clinical relevance of both end points. Reproxalap was safe and well tolerated. No clinically significant changes in safety assessments were observed. No serious or severe treatment-emergent adverse events (TEAEs) were reported. The most commonly reported TEAE was mild and transient installation site irritation after reproxalap versus vehicle administration.

Conclusion

In this well-controlled allergen chamber trial, reproxalap was statistically superior to vehicle across typical symptoms and signs of allergic conjunctivitis.

Trial Registration

NCT04207736.

Organoiridium Complexes Enhance Cellular Defense Against Reactive Aldehydes Species

Although reactive aldehyde species (RASP) are associated with the pathogenesis of many major diseases, there are currently no clinically approved treatments for RASP overload. Conventional aldehyde detox agents are stoichiometric reactants that get consumed upon reacting with their biological targets, which limits their therapeutic efficiency. To achieve longer-lasting detoxification effects, small-molecule intracellular metal catalysts (SIMCats) were used to protect cells by converting RASP into non-toxic alcohols. It was shown that SIMCats were significantly more effective in lowering cell death from the treatment with 4-hydroxynon-2-enal than aldehyde scavengers over a 72 h period. Studies revealed that SIMCats reduced the aldehyde accumulation in cells exposed to the known RASP inducer arsenic trioxide. This work demonstrates that SIMCats offer unique benefits over stochiometric agents, potentially providing new ways to combat diseases with greater selectivity and efficiency than existing approaches.

Reproxalap Activity and Estimation of Clinically Relevant Thresholds for Ocular Itching and Redness in a Randomized Allergic Conjunctivitis Field Trial

INTRODUCTION

This clinical trial assessed the activity of reproxalap, a novel reactive aldehyde species modulator, and estimated clinically relevant thresholds for changes in ocular itching and redness in an allergic conjunctivitis field trial.

METHODS

This was a randomized, double-masked, vehicle-controlled phase 2 trial. Patients with ragweed-associated allergic conjunctivitis were assessed over 28 days in an environmental setting with approximately four doses per day of either 0.25% reproxalap, 0.5% reproxalap, or vehicle. Patients recorded ocular itching, redness, tearing, and eyelid swelling scores (each with a 0-4 scale, except for a 0-3 scale for swelling), and completed the Allergic Conjunctivitis Quality of Life Questionnaire at the beginning and end of the trial.

RESULTS

Mixed model of repeated measures analysis demonstrated statistically lower itching and tearing scores (pooled P = 0.026 and P < 0.001, respectively) and numerically lower redness and eyelid swelling scores than vehicle on days when pollen exceeded the 95th percentile value. Using three anchor-based and three distribution-based approaches, the meaningful within-patient change and the between-group meaningful difference for patient-reported ocular itching and redness was estimated to be approximately 0.5. The most common treatment-emergent adverse event associated with reproxalap was transient irritation upon instillation.

CONCLUSION

In a field clinical trial, reproxalap was well tolerated and superior to vehicle in reducing ocular itching on high-pollen days. The clinical meaningfulness threshold estimates of 0.5 units are among the first such calculations generated for the standard ocular itching and redness scores, providing important context for the clinical interpretation of clinical trials in allergic conjunctivitis.

Therapeutic Targets in Allergic Conjunctivitis

Allergic conjunctivitis (AC) is a common condition resulting from exposure to allergens such as pollen, animal dander, or mold. It is typically mediated by allergen-induced crosslinking of immunoglobulin E attached to receptors on primed conjunctival mast cells, which results in mast cell degranulation and histamine release, as well as the release of lipid mediators, cytokines, and chemokines. The clinical result is conjunctival hyperemia, tearing, intense itching, and chemosis. Refractory and chronic cases can result in ocular surface complications that may be vision threatening. Patients who experience even mild forms of this disease report an impact on their quality of life. Current treatment options range from non-pharmacologic therapies to ocular and systemic options. However, to adequately control AC, the use of multiple agents is often required. As such, a precise understanding of the immune mechanisms responsible for this ocular surface inflammation is needed to support ongoing research for potential therapeutic targets such as chemokine receptors, cytokine receptors, non-receptor tyrosine kinases, and integrins. This review utilized several published articles regarding the current therapeutic options to treat AC, as well as the pathological and immune mechanisms relevant to AC. This review will also focus on cellular and molecular targets in AC, with particular emphasis on potential therapeutic agents that can attenuate the pathology and immune mechanisms driven by cells, receptors, and molecules that participate in the immunopathogenesis and immunopathology of AC.

Aldehyde Trapping by ADX-102 Is Protective against Cigarette Smoke and Alcohol Mediated Lung Cell Injury

Most individuals diagnosed with alcohol use disorders smoke cigarettes. Large concentrations of malondialdehyde and acetaldehyde are found in lungs co-exposed to cigarette smoke and alcohol. Aldehydes directly injure lungs and form aldehyde protein adducts, impacting epithelial functions. Recently, 2-(3-Amino-6-chloroquinolin-2-yl)propan-2-ol (ADX-102) was developed as an aldehyde-trapping drug. We hypothesized that aldehyde-trapping compounds are protective against lung injury derived from cigarette smoke and alcohol co-exposure. To test this hypothesis, we pretreated mouse ciliated tracheal epithelial cells with 0-100 µM of ADX-102 followed by co-exposure to 5% cigarette smoke extract and 50 mM of ethanol. Pretreatment with ADX-102 dose-dependently protected against smoke and alcohol induced cilia-slowing, decreases in bronchial epithelial cell wound repair, decreases in epithelial monolayer resistance, and the formation of MAA adducts. ADX-102 concentrations up to 100 µM showed no cellular toxicity. As protein kinase C (PKC) activation is a known mechanism for slowing cilia and wound repair, we examined the effects of ADX-102 on smoke and alcohol induced PKC epsilon activity. ADX-102 prevented early (3 h) activation and late (24 h) autodownregulation of PKC epsilon in response to smoke and alcohol. These data suggest that reactive aldehydes generated from cigarette smoke and alcohol metabolism may be potential targets for therapeutic intervention to reduce lung injury.

Reproxalap Improves Signs and Symptoms of Allergic Conjunctivitis in an Allergen Chamber: A Real-World Model of Allergen Exposure

Purpose

To assess the prophylactic and treatment activity of reproxalap, a novel reactive aldehyde species inhibitor, in a real-world model of allergen exposure.

Methods

In a randomized, double-masked, vehicle-controlled, crossover Phase 2 trial, 70 adult patients with ≥2 years of moderate to severe allergic conjunctivitis history, a positive skin test to ragweed pollen, and allergen chamber-induced ocular itching and redness scores of ≥2.5 and ≥2 (both scales range from 0 to 4), respectively, were randomized 1:1:1 to one of three sequences: 0.25% reproxalap, 0.5% reproxalap, and placebo; 0.5% reproxalap, placebo, and 0.25% reproxalap; or placebo, 0.25% reproxalap, and 0.5% reproxalap. Symptoms and conjunctival redness were assessed over 3.5 hours in an allergen chamber of aerosolized ragweed pollen (3500 grains/m³). Test article was administered bilaterally just before chamber entry and at 90 minutes after chamber entry.

Results

Reproxalap was safe and well tolerated; 66 of 70 enrolled patients completed all visits. Relative to vehicle, both concentrations of reproxalap demonstrated statistically significant and clinically relevant improvements in ocular itching, tearing, and redness over the duration of exposure in the chamber (P < 0.001 for all assessments). Prophylactic and treatment activity of drug were demonstrated.

Conclusion

In an allergen chamber, reproxalap, a novel reactive aldehyde species inhibitor, was statistically superior to vehicle across the typical symptoms and signs of allergic conjunctivitis. These data are among the first rigorous clinical results demonstrating drug improvement in allergic conjunctivitis in an allergen chamber, a real-world model of allergen exposure.

Emerging therapies for dry eye disease

INTRODUCTION

Dry Eye Disease (DED) is defined as a multifactorial disease of the ocular surface characterized by a loss of homeostasis of the tear film, and a vicious cycle of inflammation on the ocular surface. Despite its high prevalence and standing as one of the most common eye conditions seen by practitioners, the current treatment options available to patients have not proven adequate.

AREAS COVERED

This review will discuss the burden of DED, its pathophysiology, as well as emerging therapies. These therapies include immunosuppressants, immunomodulators, anti-inflammatory drugs, and corticosteroids. The mechanisms of these drugs will be discussed, as well as their phase of development and results from recent clinical trials. The literature search was performed using PubMed, Cochrane Library, Web of Science, ClinicalTrials.gov, and the Springer AdisInsight database.

EXPERT OPINION

The optimal therapy for DED is associated with improved bioavailability, minimal ocular side effects, and effective dosing. The ideal treatment has not yet been established, but this paper outlines a number of promising therapies. Continued development of therapies targeting the inflammation cascade, as well as the establishment of objective markers to quantify DED severity, are important aspects in the progression of treatment.

A Post-Acute Ocular Tolerability Comparison of Topical Reproxalap 0.25% and Lifitegrast 5% in Patients with Dry Eye Disease

Purpose

To assess the subjective eye drop experience of patients with dry eye disease (DED) over approximately 1 hour after a single dose of two formulations of reproxalap versus lifitegrast.

Methods

Two formulations of topical ocular reproxalap 0.25% were evaluated versus lifitegrast ophthalmic solution 5% in patients with DED in a single-center, double-masked, active-comparator, single-dose crossover clinical trial. Nineteen patients had test article topically administered to both eyes. Treatments were administered 2 to 4 days apart. Comfort assessments, including ocular discomfort, blurry vision, and dysgeusia assessments; ocular descriptive assessments; quality of life assessments; and overall experience questions were completed after each treatment over one hour, beginning at 90 seconds.

Results

Both reproxalap formulations scored better in ocular discomfort score (ODS), blurry vision, and dysgeusia assessments than lifitegrast at each timepoint and cumulatively over all time points after instillation. There were lower rates of negative responses for both reproxalap formulations compared to lifitegrast across ocular discomfort, blurry vision, and dysgeusia assessments, and the durations of negative responses were shorter with reproxalap than with lifitegrast. The reproxalap groups experienced fewer quality of life impacts. No significant safety findings were observed following reproxalap or lifitegrast administration.

Conclusion

The reproxalap eye drop experience over 1 hour after instillation was superior to that of lifitegrast. There were no statistically significant differences between reproxalap groups for ODS, blurry vision, or dysgeusia. The improved performance of reproxalap with regard to the most commonly reported side effects of lifitegrast (ie, ocular discomfort, blurry vision, and dysgeusia) may result in greater patient adherence and lower discontinuation rates.