Effect of a Topical Nonsteroidal Anti-Inflammatory Drug (0.1% Pranoprofen) on VEGF and COX-2 Expression in Primary Pterygium

Emerging drugs for the treatment of herpetic keratitis

INTRODUCTION

Herpes simplex keratitis stands as a prominent factor contributing to infectious blindness among developed nations. On a global scale, over 60% of the population tests positive for herpes simplex virus type-1 (HSV-1). Despite these statistics, there is currently no vaccine available for the virus. Moreover, the conventional nucleoside drugs prescribed to patients are proving ineffective in addressing issues related to drug resistance, recurrence, latency, and the escalating risk of vision loss. Hence, it is imperative to continually explore all potential avenues to restrict the virus. This review article centers on the present treatment methods for HSV-1 keratitis (HSK), highlighting the ongoing clinical trials. It delves into the emerging drugs, their mode-of-action and future therapeutics.

AREAS COVERED

The review focuses on the significance of a variety of small molecules targeting HSV-1 lifecycle at multiple steps. Peer-reviewed articles and abstracts were searched in MEDLINE, PubMed, Embase, and clinical trial websites.

EXPERT OPINION

The exploration of small molecules that target specific pathways within the herpes lifecycle holds the potential for substantial impact on the antiviral pharmaceutical market. Simultaneously, the pursuit of disease-specific biomarkers has the capacity to usher in a transformative era in diagnostics within the field.

Evaluation of Cyclooxygenase-2 and p53 Expression in Pterygium Tissue Following Preoperative Intralesional Ranibizumab Injection

Introduction: Overexpression of vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), and p53 are the postulated aetiopathogenesis in pterygium. VEGF is responsible for the induction of COX-2 expression, whereas p53 plays an important role in the regulation of VEGF. This study aimed to evaluate the immunohistochemistry of COX-2 and p53 expressions from excised pterygium tissue from patients who received intralesional ranibizumab (anti-VEGF) injection 2 weeks prior to pterygium surgery. Materials and Methods: An interventional comparative study involving patients presenting with primary pterygium was conducted between September 2015 and November 2017. The patients were randomized into either the intervention or control group. Patients in the intervention group were injected with intralesional ranibizumab (0.5 mg/0.05 ml) 2 weeks prior to surgery. Both groups underwent pterygium excision followed by conjunctival autograft. Immunohistochemistry staining was performed to evaluate COX-2 and p53 expressions in the excised pterygium tissue. Results: A total of 50 patients (25 in both the intervention and control groups) were recruited. There were 34 (68%) patients with grade III pterygium and 16 (32%) patients with grade IV pterygium. There was statistically significant difference in reduction of COX-2 expression in the epithelial layer [84.0% (95% CI: 63.9, 95.5)] (p = 0.007) and stromal layer [84.0% (95% CI: 63.9, 95.5)] (p < 0.001) between intervention and control groups. There was no significant difference in the reduction of p53 expression between the two groups. Conclusion: This study demonstrated the possible use of intralesional anti-VEGF treatment prior to pterygium excision as a potential future modality of adjunctive therapy for pterygium surgery.

Enhanced Transdermal Delivery of Pranoprofen Using a Thermo-Reversible Hydrogel Loaded with Lipid Nanocarriers for the Treatment of Local Inflammation

A biocompatible topical thermo-reversible hydrogel containing Pranoprofen (PF)-loaded nanostructured lipid carriers (NLCs) was studied as an innovative strategy for the topical treatment of skin inflammatory diseases. The PF-NLCs-F127 hydrogel was characterized physiochemically and short-time stability tests were carried out over 60 days. In vitro release and ex vivo human skin permeation studies were carried out in Franz diffusion cells. In addition, a cytotoxicity assay was studied using the HaCat cell line and in vivo tolerance study was performed in humans by evaluating the biomechanical properties. The anti-inflammatory effect of the PF-NLCs-F127 was evaluated in adult male Sprague Daw-ley^® rats using a model of inflammation induced by the topical application of xylol for 1 h. The developed PF-NLCs-F127 exhibited a heterogeneous structure with spherical PF-NLCs in the hydrogel. Furthermore, a thermo-reversible behaviour was determined with a gelling temperature of 32.5 °C, being close to human cutaneous temperature and thus favouring the retention of PF. Furthermore, in the ex vivo study, the amount of PF retained and detected in human skin was high and no systemic effects were observed. The hydrogel was found to be non-cytotoxic, showing cell viability of around 95%. The PF-NLCs-F127 is shown to be well tolerated and no signs of irritancy or alterations of the skin's biophysical properties were detected. The topical application of PF-NLCs-F127 hydrogel was shown to be efficient in an inflammatory animal model, preventing the loss of stratum corneum and reducing the presence of leukocyte infiltration. The results from this study confirm that the developed hydrogel is a suitable drug delivery carrier for the transdermal delivery of PF, improving its dermal retention, opening the possibility of using it as a promising candidate and safer alternative to topical treatment for local skin inflammation and indicating that it could be useful in the clinical environment.