Desloratadine: a nonsedating antihistamine

Combining High-Resolution Mass Spectrometry and Chemiluminescence Analysis to Characterize the Composition and Fate of Total N-Nitrosamines in Wastewater Treatment Plants

Monitoring the prevalence and persistence of N-nitrosamines and their precursors in wastewater treatment plants (WWTPs) and effluent-receiving aquatic compartments is a priority for utilities practicing wastewater recycling or exploiting wastewater-impacted source waters. In this work, we developed an analytical framework that combines liquid chromatography-high-resolution mass spectrometry (LC-HRMS) with acidic triiodide-chemiluminescence analysis to characterize the composition and fate of total N-nitrosamines (TONO) and their precursors along the treatment trains of eight WWTPs in New York. Through the parallel application of LC-HRMS and chemiluminescence methods, the TONO scores for 41 N-nitrosamines containing structurally diverse substituents on their amine nitrogen were derived based on their solid-phase extraction recoveries and conversion efficiencies to nitric oxide. Correcting the compositional analysis of TONO using the TONO scores of target N-nitrosamines refined the assessment of the reduction or accumulation of TONO and their precursors across treatment steps in WWTPs. Nontargeted analysis prioritized seven additional N-nitrosamines for confirmation by reference standards, including three previously uncharacterized species: N-nitroso-tert-butylphenylamine, N-nitroso-2-pyrrolidinmethanol, and N-nitrosodesloratadine, although they only served as minor components of TONO. Overall, our study establishes an adaptable methodological framework for advancing the quantitative and qualitative analysis of specific and unknown components of TONO across water treatment and reuse scenarios.

Werner Salt as Nickel and Ammonia Source for Photochemical Synthesis of Primary Aryl Amines

Cheap, stable and easy-to-handle Werner ammine salts have been known for more than a century; but they have been rarely used in organic synthesis. Herein, we report that the Werner hexammine complex [Ni(NH3 )6 ]Cl2 can be used as both a nitrogen and a catalytic nickel source that allow for the efficient amination of aryl chlorides in the presence of a catalytic amount of bipyridine ligand under the irradiation of 390-395 nm light without the need of any additional catalysts. More than 80 aryl chlorides, including more than 20 drug molecules, were aminated, demonstrating the practicality and generality of this method in synthetic chemistry. A slow NH3 release mechanism is in operation, obviating the problem of catalyst poisoning. Still interestingly, we show that the Werner salt can be easily recovered and reused, solving the problem of difficult recovery of transition metal nickel catalysts. The protocol thus provides an efficient new strategy for the synthesis of primary aryl amines.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

The safety and efficacy of desloratadine for the management of allergic disease

Allergic disease is an increasing problem worldwide. Allergic rhinitis, an inflammatory response to an allergen, affects an estimated 20-40 million people in the US, while chronic idiopathic urticaria is a dermatoallergic condition that affects 0.1-3% of people in the US and Europe. The primary goals of treatment for allergic rhinitis are to reduce symptoms, which include sneezing, rhinorrhoea and nasal congestion, improve quality of life and prevent the sequelae associated with this disease, while the goal for chronic idiopathic urticaria is the rapid and prolonged control of symptoms. Quantitatively, histamine is the most abundant mediator present during an allergic episode - thus, antihistamines (historically called histamine H(1) receptor antagonists, now called H(1) receptor inverse agonists) are a first-line defense against allergic rhinitis and chronic idiopathic urticaria. Although first-generation antihistamines can cause sedation and cognitive impairment, second-generation antihistamines are relatively non-sedating and free of such adverse events owing to their comparative inability to penetrate the blood-brain barrier. Desloratadine is one such second-generation antihistamine and is indicated for the treatment of allergic diseases, including allergic rhinitis and chronic idiopathic urticaria. It has proven efficacy against the symptoms associated with seasonal and perennial allergic rhinitis, including nasal congestion, and chronic idiopathic urticaria. As a result, it has been shown to improve patients' quality of life. The safety and efficacy profiles of desloratadine are well established, and published postmarketing analyses have assessed >54 000 patients. Although earlier second-generation antihistamines have been associated with cardiovascular adverse effects, desloratadine has been shown to be safe and well tolerated at nine times the recommended dose. In addition, it has been shown to not interact with concomitantly administered drugs and food. Overall, current data indicate that desloratadine is a safe and effective treatment for allergic diseases.

Desloratadine for chronic idiopathic urticaria: a review of clinical efficacy

Chronic idiopathic urticaria (CIU) is a disabling affliction that considerably limits patients' daily activities and interferes with sleep. Clinical studies have shown that histamine H1-receptor antagonists (antihistamines) are highly effective for inhibiting the hives/wheals and pruritus associated with CIU, as well as improving patients' quality of life. Desloratadine is a rapid-acting, once-daily, nonsedating selective H1-receptor antagonist/inverse receptor agonist with proven clinical efficacy in patients with CIU. It has 10-20 times the in vivo H1 receptor-binding affinity of loratadine, its parent compound, and 52-194 times the H1 receptor-binding affinity of cetirizine, ebastine, loratadine, and fexofenadine. Desloratadine displays linear pharmacokinetics after oral administration. Age and sex have no apparent effect on the drug's metabolism and elimination, and food does not affect its bioavailability or absorption. Desloratadine also exerts anti-inflammatory effects via mechanisms that are independent of H1-receptor antagonism. Results from randomized, double-blind, placebo-controlled studies of 6 weeks' duration in adults and adolescents with moderate-to-severe CIU indicate that desloratadine significantly minimizes the severity of pruritus, reduces the number and size of hives, and improves disease-impaired sleep and daily activities. Improvements were noted after a single dose of desloratadine and were maintained over 6 weeks of treatment. Desloratadine was safe and well tolerated in clinical trials of patients with CIU. The adverse effect profile of desloratadine in adults, as well as in children aged from 6 months to 11 years, is comparable to that of placebo. Evaluations of cognitive and psychomotor performance in adults indicate no impairment of function with dosages of desloratadine 5 mg/day. In conclusion, desloratadine is an important therapeutic option for prompt and enduring symptom relief in patients with moderate-to-severe CIU. In addition to efficacy and safety, desloratadine affords a convenient administration regimen, rapid onset of action, and an absence of drug-drug or drug-food interactions. Other important prescribing considerations are that, unlike all first-generation and some second-generation antihistamines, desloratadine is nonsedating at its clinically approved dosage and does not impair psychomotor function.

Desloratadine: an update of its efficacy in the management of allergic disorders

Desloratadine (Clarinex, Neoclarityn, Aerius, Azomyr, Opulis, Allex), the principal metabolite of loratadine, is itself an orally active, nonsedating, peripheral histamine H(1)-receptor antagonist. It is indicated in the US and Europe for the treatment of seasonal allergic rhinitis (SAR), perennial allergic rhinitis (PAR) and chronic idiopathic urticaria (CIU). It has a rapid onset of effect, efficacy throughout a 24-hour dosage interval, and sustained efficacy in these allergic conditions, as demonstrated in placebo-controlled trials of up to 6 weeks' duration in adult and adolescent patients. At present, there are no published direct comparisons of desloratadine and other H(1)-antihistamines; however, the principal, potential clinical advantages of desloratadine over late-generation H(1)-antihistamines are the drug's decongestant activity, which has been corroborated in several studies of patients with allergic rhinitis, and its anti-inflammatory effects. Indeed, the decongestant activity of desloratadine did not differ from that of pseudoephedrine in a trial in patients with SAR, and in patients with SAR and coexisting asthma, desloratadine reduced asthma symptoms and beta(2)-agonist use, and improved forced expiratory flow in 1 second. However, these issues warrant further study. Desloratadine is generally well tolerated. The overall incidence of adverse events in adults, adolescents and children was not significantly different to that with placebo, and similar proportions of desloratadine or placebo recipients reported events such as pharyngitis, dry mouth, myalgia, somnolence, dysmenorrhoea or fatigue. Desloratadine does not cause sedation or prolong the corrected QT (QTc) interval, can be administered without regard to concurrent intake of food and grapefruit juice, and appears to have negligible potential for drug interactions mediated by several metabolic systems.

CONCLUSION

Although comparative studies with second-generation and other recently developed H(1)-antihistamines are needed to define the drug's clinical profile more clearly, desloratadine can be expected to claim a prominent place in the management of allergic disorders in general, and in the amelioration of specific symptoms of allergy (e.g. nasal congestion) in patients with such disorders.