Nose-to-Brain (N2B) Delivery: An Alternative Route for the Delivery of Biologics in the Management and Treatment of Central Nervous System Disorders

In recent years, there have been a growing number of small and large molecules that could be used to treat diseases of the central nervous system (CNS). Nose-to-brain delivery can be a potential option for the direct transport of molecules from the nasal cavity to different brain areas. This review aims to provide a compilation of current approaches regarding drug delivery to the CNS via the nose, with a focus on biologics. The review also includes a discussion on the key benefits of nasal delivery as a promising alternative route for drug administration and the involved pathways or mechanisms. This article reviews how the application of various auxiliary agents, such as permeation enhancers, mucolytics, in situ gelling/mucoadhesive agents, enzyme inhibitors, and polymeric and lipid-based systems, can promote the delivery of large molecules in the CNS. The article also includes a discussion on the current state of intranasal formulation development and summarizes the biologics currently in clinical trials. It was noted that significant progress has been made in this field, and these are currently being applied to successfully transport large molecules to the CNS via the nose. However, a deep mechanistic understanding of this route, along with the intimate knowledge of various excipients and their interactions with the drug and nasal physiology, is still necessary to bring us one step closer to developing effective formulations for nasal-brain drug delivery.

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.

Drug-Induced Rhinitis: Narrative Review

OBJECTIVES

Rhinitis, one of the most common inflammatory conditions of the nasal mucosa, is known to affect a large proportion of people worldwide. It is generally classified into allergic and non-allergic types and both are associated with several unpleasant symptoms. Several medications prescribed for different medical conditions can cause unpleasant rhinitis as an adverse effect, which is known as drug-induced non-allergic rhinitis. The aims of this article were to review the literature to identify drugs that could induce rhinitis, prevalence of drug-induced rhinitis, and the associated pathogenic mechanisms if known.

METHODS

Literature search screening for eligible papers published up to December 31st, 2021, in Medline (via PubMed) and Embase was conducted. The search included the following combination of keywords and terms: rhinitis, sneezing, congestion, allergic, non-allergic, rhinorrhea, vasomotor, medication, drug-induced.

RESULTS

The review findings suggest that 12 subtypes of drugs potentially could induce rhinitis. Based on their mechanisms of action, the pathogenic causes for the induction of rhinitis have been recognized for some drugs, while others remain unknown.

CONCLUSION

Awareness of the list of drugs that reportedly induce non-allergic nasal symptoms, along with taking the patient's medication history, is important in the diagnosis of rhinitis.

Intranasal corticosteroid and oxymetazoline for chronic rhinitis: a systematic review

OBJECTIVE

This study aimed to summarise the evidence for efficacy of combination treatment of intranasal corticosteroid spray with oxymetazoline hydrochloride nasal spray for chronic rhinitis.

METHOD

Nine databases were systematically searched from study inception in September 2016 to 1 June 2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was followed.

RESULTS

A total of 130 studies were screened, and 4 randomised controlled trials comprising 838 patients met inclusion criteria. The study found superior improvement of nasal congestion from onset of treatment to completion in intranasal corticosteroid spray and oxymetazoline hydrochloride groups compared with control groups. Intranasal corticosteroid spray and oxymetazoline hydrochloride use resulted in higher nasal volume (standard error of mean 1, 15.8 + 1.1 ml; p < .03) compared with either placebo (12.1 + 0.9 ml) or oxymetazoline hydrochloride (12.4 + 0.8 ml) alone (p = 0.003).

CONCLUSION

Intranasal corticosteroid spray and oxymetazoline hydrochloride combination treatment may be superior in reducing rhinitis symptoms compared with either intranasal corticosteroid spray or oxymetazoline hydrochloride alone, without inducing rhinitis medicamentosa.

Rhinitis Phenotypes

Rhinitis is an umbrella term of a group of upper airway diseases with nasal symptoms and signs with different etiologies and various clinical features or traits. It can be classified into different "phenotypes," based on these observable traits. A proper differential diagnosis is necessary to adequately manage the disease. The objective of this review is to clarify the concept of rhinitis phenotypes while analyzing the clinical features and/or traits of each in order to determine a proper differential diagnosis and appropriate treatment.

Autonomic nervous system dysfunction and sinonasal symptoms

Background

The autonomic nervous system (ANS) richly innervates the nose and paranasal sinuses, and has a significant role in lower airway diseases, e.g., asthma. Nonetheless, its contribution to sinonasal symptoms is poorly understood. This review aimed to explore the complex relationship between the ANS and sinonasal symptoms, with reference to systemic diseases and triggers of ANS dysfunction.

Methods

A review of articles published in English was conducted by searching medical literature databases with the key words “autonomic nervous system” and (“sinusitis” or “nose” or “otolaryngology”). All identified abstracts were reviewed, and, from these, relevant published whole articles were selected.

Results

The ANS has a significant role in the pathophysiologic mechanisms that produce sinonasal symptoms. There was limited evidence that describes the relationship of the ANS in sinonasal disease with systemic conditions, e.g. hypertension. There was some evidence to support mechanisms related to physical and psychological stressors in this relationship.

Conclusion

The role of ANS dysfunction in sinonasal disease is highly complex. The ANS sits within a web of multiple factors, including personality and psychological distress, that contribute to sinonasal symptoms. Further research will help to clarify the etiology of ANS dysfunction and its contribution to common systemic conditions.

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.

Measurable impact of acupuncture on mucosal swelling of inferior turbinates: a prospective, randomized, controlled study

CONCLUSIONS

Sham acupuncture turned out to be more effective than expected. The effect of acupuncture cannot be assessed by optical rhinometry (ORM).

OBJECTIVES

In most cases nasal congestion is caused by hypertrophy of the inferior turbinate as a result of allergic and chronic rhinitis. Topical decongestants cause severe side effects. As a consequence, there is an increasing demand for alternative treatment options such as traditional Chinese medicine (TCM).

METHODS

A total of 25 patients with nasal congestion due to hypertrophic inferior turbinate were recruited. The mucosal swelling status of the inferior turbinate was assessed by continuous ORM for 20 min. Patients were asked to score the severity of their nasal congestion on a visual analogue scale (VAS) before and 10 and 20 min after acupuncture. Specific verum acupuncture points related to nasal congestion were tested against non-specific control sham acupuncture points.

RESULTS

Sham acupuncture improved VAS scores, whereas ORM measured an increase in nasal swelling. The ORM revealed a quicker onset of the effect of verum acupuncture on the nasal blood flow. Also, verum acupuncture reaches its maximum effect in a shorter time period, so that the net reaction time was much shorter. However, ORM could not prove a decongestant effect of verum acupuncture on inferior turbinate.