Effect of fexofenadine hydrochloride on allergic rhinitis aggravated by air pollutants

Efficacy, safety, and serum cytokine modulation by olopatadine hydrochloride and desloratadine citrate disodium combination therapy in urticaria

OBJECTIVES

To assess the efficacy, safety, and impact on serum cytokines of olopatadine hydrochloride (OLP) combined with desloratadine citrate disodium (DES) in treating urticaria.

METHODS

We retrospectively analyzed 114 urticaria patients treated at the Affiliated Hospital of Xinyang Vocational and Technical College from March 2020 to March 2023. The control group (55 patients) received DES, while the research group (59 patients) received OLP+DES combination therapy. We compared efficacy, safety (including epigastric pain, dry mouth, lethargy, dizziness, and fatigue), changes in serum cytokines (interleukin [IL]-2, IL-4, and interferon [IFN]-γ), symptom resolution (wheal number, wheal size, and itching degree), and 3-month recurrence rates. A univariate analysis was also conducted to identify factors influencing urticaria recurrence.

RESULTS

The research group exhibited a significantly higher overall efficacy rate, lower incidence of adverse events, and reduced recurrence rates at 3 months (all P<0.05) compared to the control group. Post-treatment, the research group showed significant increases in IL-2 and IFN-γ levels and reductions in IL-4 levels, wheal number, wheal size, and itching degree (all P<0.05). Factors such as history of drinking/smoking, IL-2 levels, and treatment method were associated with urticaria recurrence (all P<0.05).

CONCLUSIONS

The combination of OLP and DES is an effective and safe treatment option for urticaria, significantly improving serum cytokine profiles, alleviating symptoms, and reducing recurrence risk.

The Relationship of Climate Change to Rhinitis

Evidence is mounting that climate change is having a significant impact on exacerbations of rhinitis. Concomitantly, the prevalence of allergic rhinitis is increasing at an accelerated rate. We herein explore the impact of carbon dioxide, barometric pressure and humidity changes, and anthropogenic pollutants on aeroallergens and rhinitis hypersensitivity. Important immune mechanisms underlying the climate-driven effects on rhinitis are discussed. Also, climate change is shifting ecological zones and seasons, increasing weather extremes, and altering regional atmospheric and environmental conditions. The direct impact of these factors on promoting allergic and nonallergic rhinitis is reviewed.

Air pollution and rhinitis

Rhinitis arises from either allergic or non-allergic inflammation of the nasal mucosa, characterized by the infiltration of inflammatory cells into the tissue and nasal secretions, along with structural alterations in the nasal mucosa. The pathways through which air pollution affects rhinitis may diverge from those affecting asthma. This article aims to review the effects of diverse air pollutants on the nose, the correlation of climate change and pollution, and how they aggravate the symptoms of patients with rhinitis.

Respiratory Health Effects of Air Pollutants

Air pollution is a risk factor for asthma and respiratory infection. Avoidance of air pollution is the best approach to mitigating the impacts of pollution. Personal preventive strategies are possible, but policy interventions are the most effective ways to prevent pollution and its effect on asthma and respiratory infection.

Bioequivalence of 2 Pediatric Formulations of Fexofenadine Hydrochloride Oral Suspension

Fexofenadine hydrochloride (HCl) is a second-generation, nonsedating, histamine H1-receptor antagonist used to manage seasonal allergic rhinitis and chronic idiopathic urticaria. A new oral pediatric suspension of fexofenadine HCl has been developed, with the preservative potassium sorbate replacing parabens. The objective of this phase 1 single-center, open-label, randomized, 2-treatment, full-replicated, 4-period, 2-sequence crossover study in healthy adult volunteers was to assess the bioequivalence of 30 mg of the new oral suspension of fexofenadine HCl (test) versus 30 mg of the marketed pediatric oral suspension of fexofenadine HCl (reference). The replicate design was based on the high intra-individual variability of fexofenadine (>30% on Cmax ). The study comprised 68 randomized and treated volunteers. Plasma concentrations of fexofenadine were similar following the administration of a single dose of each formulation. Cmax , AUClast , AUC, median tmax , and mean t1/2z were similar between administrations of the same fexofenadine formulation and between formulations. A high intra-individual variability was confirmed with both formulations. Bioequivalence of the test and reference fexofenadine HCl formulations was demonstrated as the 90% confidence intervals of the geometric least squares mean ratio for Cmax , AUClast , and AUC of fexofenadine were all within the bioequivalence range of 0.80-1.25. There were no serious adverse events (AEs) or study discontinuations due to treatment-emergent AEs with either fexofenadine HCl formulation. The new paraben-free fexofenadine HCl 30-mg oral suspension and marketed fexofenadine HCl 30-mg pediatric oral suspension are bioequivalent under fasting conditions, with no safety concerns and a safety profile consistent with the known profile of fexofenadine.

Pollen respiratory allergy: Is it really seasonal?

Allergic rhinitis (AR) is a highly prevalent respiratory condition that carries a heavy burden and can have a significant impact on patient quality of life. AR is caused by seasonal or perennial exposure to outdoor pollens and molds as well as indoor allergic triggers. In this review article, we discuss the factors associated with the development of AR throughout the year and the fact that patients with AR need continuous treatment rather than seasonal treatment. Conventionally, AR has been mainly categorized into seasonal AR and perennial AR, but these classes do not seem to be well-adapted. Climate changes, temperature changes, and high carbon dioxide (CO₂) concentration affect the growth of plants and increase the length of pollen seasons and pollen allergenicity. Air pollution aggravates allergic sensitization symptoms in AR sensitized individuals. Due to increased air pollution and indefinite pollen seasons AR symptoms are present throughout the year. Patients with AR often need continuous treatment, which should be considered while making the strategy for treating allergic rhinitis sufferers. Management of AR involves avoiding the allergen, medications for symptomatic relief, anti-inflammatory therapies, and allergy immunotherapy. Although the first-generation H₁-antihistamines reduce AR symptoms, they cause sedation and impair cognitive functions; thus, second-generation antihistamines (ie, levocetirizine, loratadine, bilastine, fexofenadine) are preferred. The efficacy and safety of fexofenadine for the treatment of seasonal allergic rhinitis (SAR) symptoms have been demonstrated by numerous clinical studies, irrespective of the season and underlying allergen. In this review, we discuss the allergic rhinitis classification, the role of climate change, air pollution, and factors contributing to year-round symptoms in patients with AR and the need for continuous pharmacological treatment for management.

Virtual screening and molecular dynamics simulations provide insight into repurposing drugs against SARS-CoV-2 variants Spike protein/ACE2 interface

After over two years of living with Covid-19 and hundreds of million cases worldwide there is still an unmet need to find proper treatments for the novel coronavirus, due also to the rapid mutation of its genome. In this context, a drug repositioning study has been performed, using in silico tools targeting Delta Spike protein/ACE2 interface. To this aim, it has been virtually screened a library composed by 4388 approved drugs through a deep learning-based QSAR model to identify protein-protein interactions modulators for molecular docking against Spike receptor binding domain (RBD). Binding energies of predicted complexes were calculated by Molecular Mechanics/Generalized Born Surface Area from docking and molecular dynamics simulations. Four out of the top twenty ranking compounds showed stable binding modes on Delta Spike RBD and were evaluated also for their effectiveness against Omicron. Among them an antihistaminic drug, fexofenadine, revealed very low binding energy, stable complex, and interesting interactions with Delta Spike RBD. Several antihistaminic drugs were found to exhibit direct antiviral activity against SARS-CoV-2 in vitro, and their mechanisms of action is still debated. This study not only highlights the potential of our computational methodology for a rapid screening of variant-specific drugs, but also represents a further tool for investigating properties and mechanisms of selected drugs.

Mammalian derived lipocalin and secretoglobin respiratory allergens strongly bind ligands with potentially immune modulating properties

Allergens from furry animals frequently cause sensitization and respiratory allergic diseases. Most relevant mammalian respiratory allergens belong either to the protein family of lipocalins or secretoglobins. Their mechanism of sensitization remains largely unresolved. Mammalian lipocalin and secretoglobin allergens are associated with a function in chemical communication that involves abundant secretion into the environment, high stability and the ability to transport small volatile compounds. These properties are likely to contribute concomitantly to their allergenic potential. In this study, we aim to further elucidate the physiological function of lipocalin and secretoglobin allergens and link it to their sensitizing capacity, by analyzing their ligand-binding characteristics. We produced eight major mammalian respiratory allergens from four pet species in E.coli and compared their ligand-binding affinities to forty-nine ligands of different chemical classes by using a fluorescence-quenching assay. Furthermore, we solved the crystal-structure of the major guinea pig allergen Cav p 1, a typical lipocalin. Recombinant lipocalin and secretoglobin allergens are of high thermal stability with melting temperatures ranging from 65 to 90°C and strongly bind ligands with dissociation constants in the low micromolar range, particularly fatty acids, fatty alcohols and the terpene alcohol farnesol, that are associated with potential semiochemical and/or immune-modulating functions. Through the systematic screening of respiratory mammalian lipocalin and secretoglobin allergens with a large panel of potential ligands, we observed that total amino acid composition, as well as cavity shape and volume direct affinities to ligands of different chemical classes. Therefore, we were able to categorize lipocalin allergens over their ligand-binding profile into three sub-groups of a lipocalin clade that is associated with functions in chemical communication, thus strengthening the function of major mammalian respiratory allergens as semiochemical carriers. The promiscuous binding capability of hydrophobic ligands from environmental sources warrants further investigation regarding their impact on a molecule's allergenicity.