A reappraisal of the mucoactive activity and clinical efficacy of bromhexine

In Silico Identification of Potential Inhibitors of SARS-CoV-2 Main Protease (Mpro)

The ongoing Coronavirus Disease 19 (COVID-19) pandemic has had a profound impact on the global healthcare system. As the SARS-CoV-2 virus, responsible for this pandemic, continues to spread and develop mutations in its genetic material, new variants of interest (VOIs) and variants of concern (VOCs) are emerging. These outbreaks lead to a decrease in the efficacy of existing treatments such as vaccines or drugs, highlighting the urgency of new therapies for COVID-19. Therefore, in this study, we aimed to identify potential SARS-CoV-2 antivirals using a virtual screening protocol and molecular dynamics simulations. These techniques allowed us to predict the binding affinity of a database of compounds with the virus Mpro protein. This in silico approach enabled us to identify twenty-two chemical structures from a public database (QSAR Toolbox Ver 4.5 ) and ten promising molecules from our in-house database. The latter molecules possess advantageous qualities, such as two-step synthesis, cost-effectiveness, and long-lasting physical and chemical stability. Consequently, these molecules can be considered as promising alternatives to combat emerging SARS-CoV-2 variants.

Beyond the lungs: Exploring diverse applications of bromhexine and ambroxol

The respiratory tract is commonly affected in multisystem disorders. Although many drugs have been developed to target various components of these diseases, there is still a need for effective treatments that can address both respiratory and non-respiratory symptoms. Bromhexine and ambroxol are mucolytic agents with a good safety profile that are widely used to treat respiratory conditions. These compounds seem to present several unresolved questions when carrying out their therapeutic effects, suggesting that they may not merely improve mucociliary clearance. These assumptions have provided the basis for researchers to investigate the specific characteristics of bromhexine and ambroxol. This has led to the emergence of several repositionings for this compound. Accordingly, these compounds have also shown potential benefits in the treatment of various extrapulmonary disorders, including neurological disorders, and inflammatory bowel disease. We gathered findings from relevant studies published in English between 1970 and December 2023 by searching databases including PubMed, Google Scholar, Scopus, Embase, and the Cochrane Library. Our findings revealed that most of the research on extrapulmonary uses has been conducted at the preclinical level. Accordingly, more clinical studies are needed to determine the effectiveness of bromhexine and ambroxol in these conditions. This article provides an overview of the potential extrapulmonary applications of bromhexine and ambroxol and discusses the potential advantages of using these drugs in multisystem disorders.

Enhancing pulmonary delivery and immunomodulation of respiratory diseases through virus-mimicking nanoparticles

This study introduces the nanobromhexine lipid particle (NBL) platform designed for effective pulmonary drug delivery. Inspired by respiratory virus transport mechanisms, NBL address challenges associated with mucus permeation and inflammation in pulmonary diseases. Composed of low molecular weight polyethylene glycol-coated lipid nanoparticles with bromhexine hydrochloride, NBL exhibit a size of 118 ± 24 nm, a neutral zeta potential, osmolarity of 358 ± 28 mOsmol/kg, and a pH of 6.5. Nebulizing without leakage and showing no toxicity to epithelial cells, NBL display mucoadhesive properties with a 60% mucin-binding efficiency. They effectively traverse the dense mucus layer of Calu-3 cultures in an air-liquid interface, as supported by a 55% decrease in MUC5AC density and a 29% increase in nanoparticles internalization compared to non-exposed cells. In assessing immunomodulatory effects, NBL treatment in SARS-CoV-2-infected lung cells leads to a 40-fold increase in anti-inflammatory MUC1 gene expression, a proportional reduction in pro-inflammatory IL-6 expression, and elevated anti-inflammatory IL-10 expression. These findings suggest a potential mechanism to regulate the excessive IL-6 expression triggered by virus infection. Therefore, the NBL platform demonstrates promising potential for efficient pulmonary drug delivery and immunomodulation, offering a novel approach to addressing mucus permeation and inflammation in pulmonary diseases.

Effect of bromhexine in hospitalized patients with COVID-19

BACKGROUND

Bromhexine is a potent inhibitor of transmembrane serine protease 2 and appears to have an antiviral effect in controlling influenza and parainfluenza infection; however, its efficacy in COVID-19 is controversial.

METHODS

A group of hospitalized patients with confirmed COVID-19 pneumonia were randomized using 1:1 allocation to either standard treatment lopinavir/ritonavir and interferon beta-1a or bromhexine 8 mg four times a day in addition to standard therapy. The primary outcome was clinical improvement within 28 days, and the secondary outcome measures were time to hospital discharge, all-cause mortality, duration of mechanical ventilation, the temporal trend in 2019-nCoV reverse transcription-polymerase chain reaction positivity and the frequency of adverse drug events within 28 days from the start of medication.

RESULTS

A total of 111 patients were enrolled in this randomized clinical trial and data from 100 patients (48 patients in the treatment arm and 52 patients in the control arm) were analyzed. There was no significant difference in the primary outcome of this study, which was clinical improvement. There was no significant difference in the average time to hospital discharge between the two arms. There were also no differences observed in the mean intensive care unit stay, frequency of intermittent mandatory ventilation, duration of supplemental oxygenation or risk of death by day 28 noted between the two arms.

CONCLUSION

Bromhexine is not an effective treatment for hospitalized patients with COVID-19. The potential prevention benefits of bromhexine in asymptomatic postexposure or with mild infection managed in the community remain to be determined.

Inhibition of TRPA1, Endoplasmic Reticulum Stress, Human Airway Epithelial Cell Damage, and Ectopic MUC5AC Expression by Vasaka (Adhatoda vasica; Malabar Nut) Tea

This study tested whether a medicinal plant, Vasaka, typically consumed as a tea to treat respiratory malaise, could protect airway epithelial cells (AECs) from wood smoke particle-induced damage and prevent pathological mucus production. Wood/biomass smoke is a pneumotoxic air pollutant. Mucus normally protects the airways, but excessive production can obstruct airflow and cause respiratory distress. Vasaka tea pre- and co-treatment dose-dependently inhibited mucin 5AC (MUC5AC) mRNA induction by AECs treated with wood smoke particles. This correlated with transient receptor potential ankyrin-1 (TRPA1) inhibition, an attenuation of endoplasmic reticulum (ER) stress, and AEC damage/death. Induction of mRNA for anterior gradient 2, an ER chaperone/disulfide isomerase required for MUC5AC production, and TRP vanilloid-3, a gene that suppresses ER stress and wood smoke particle-induced cell death, was also attenuated. Variable inhibition of TRPA1, ER stress, and MUC5AC mRNA induction was observed using selected chemicals identified in Vasaka tea including vasicine, vasicinone, apigenin, vitexin, isovitexin, isoorientin, 9-oxoODE, and 9,10-EpOME. Apigenin and 9,10-EpOME were the most cytoprotective and mucosuppressive. Cytochrome P450 1A1 (CYP1A1) mRNA was also induced by Vasaka tea and wood smoke particles. Inhibition of CYP1A1 enhanced ER stress and MUC5AC mRNA expression, suggesting a possible role in producing protective oxylipins in stressed cells. The results provide mechanistic insights and support for the purported benefits of Vasaka tea in treating lung inflammatory conditions, raising the possibility of further development as a preventative and/or restorative therapy.

Therapeutic potential of bromhexine for acute itch in mice: Involvement of TMPRSS2 and kynurenine pathway

Itching is an unpleasant sensation on the skin that could negatively impact the quality of life. Over the years, many non-pharmacological and pharmacological approaches have been introduced to mitigate this burdensome condition; However, the effectiveness of these methods remains questioned. Bromhexine, derived from the Adhatoda vasica plant, is a safe drug with minimal side effects. It has been widely used in managing respiratory symptoms over the years. The results of our study revealed that bromhexine has the potential to alleviate acute itch induced by Compound 48/80, a known mast cell destabilizer. According to our findings, bromhexine exerts its antipruritic effects primarily by inhibiting the Transmembrane Protein Serine Protease 2 (TMPRSS2) and, to a lesser extent, by decreasing the activation of the Kynurenine Pathway (KP). We further investigated the KP involvement by administrating 1-Methyl Tryptophan (1-MT), a known indoleamine-2,3-dioxygenase (IDO) inhibitor. 1-MT was found to be effective in reducing the itch itself. Moreover, co-administration of bromhexine and 1-MT resulted in synergistic antipruritic effects, suggesting that KP plays a role in acute itch. To conclude, we have presented for the first time a repositioning of bromhexine as a treatment for acute itch. In addition, we addressed the involvement of TMPRSS2 and KP in this process.

Pharmacotherapy prescribing pattern and outcome for hospitalized patients with severe and critical COVID-19

There are many treatment modalities for COVID-19 – with varied outcome. Therefore, authors designed this study to assess prescribing patterns and the clinical outcome for hospitalized patients with severe and critical COVID-19 so as to determine the most effective approach.

Authors conducted a retrospective observational study on 346 adult patients with either severe or critical COVID-19, who were admitted to public hospitals in Al-Najaf city, Iraq from June to September 2020. Patients’ information, medications and outcomes were collected from their medical records in the registered office of the hospital.

A total of 346 patients were enrolled, with a majority of patients being adults above 35 years old and male (70.2%). Most patients (81%) received corticosteroid as dexamethasone, and about 45% of all patients were given convalescent plasma therapy, while a few patients were prescribed antiviral favipiravir (23%) and lopinavir/ritonavir (19%). As supportive care medications, anticoagulant such as enoxaparin was administered to most of the patients (93%) and more than half of all patients received the broad-spectrum antibiotic, meropenem.

The majority of the patients recovered and were discharged alive (66%), however, the in- hospital mortality rate was 26%. Interestingly, patients treated with enoxaparin alone or in combination with hydroxychloroquine were associated with better outcome.

The prescribing pattern of COVID-19 specific medications and supportive care is aligned with guideline recommendations and associated with a beneficial therapeutic outcome.

Electrodeposition of Cobalt Oxides on Carbon Nanotubes for Sensitive Bromhexine Sensing

We develop an electrochemical sensor for the determination of bromhexine hydrochloride (BHC), a widely use mucolytic drug. The sensor is prepared by electrodeposition of cobalt oxides (CoO_x) on a glassy carbon electrode modified with carboxylated single-walled carbon nanotubes (SWCNT). A synergistic effect between CoO_x and SWCNT is observed, leading to a significant improvement in the BHC electrooxidation current. Based on cyclic voltammetry studies at varying scan rates, we conclude that the electrochemical oxidation of BHC is under mixed diffusion–adsorption control. The proposed sensor allows the amperometric determination of BHC in a linear range of 10–500 µM with a low applied voltage of 0.75 V. The designed sensor provides reproducible measurements, is not affected by common interfering substances, and shows excellent performance for the analysis of BHC in pharmaceutical preparations.

Efficacy and Safety of Ganduqing Granules in Treating the Common Cold: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

Background

There is no clear evidence-based medicine that points to the most effective drug treatments for the common cold. In view of its ability to relieve symptoms and shorten the disease course, as well as its minimal side effects, traditional Chinese medicine (TCM) has been widely used to treat the common cold. However, there is a lack of strong evidence to support the clinical efficacy of TCM. This study aimed to evaluate the efficacy and safety of Ganduqing granules in the treatment of the common cold based on the network pharmacology analysis.

Methods

In this multicenter, randomized, double-blind, placebo-controlled trial, 60 eligible subjects will be randomly assigned to either the intervention group or the placebo group. The intervention group will be treated with Ganduqing granules, while the placebo group will be treated with placebo. After 5 days of intervention, the efficacy and safety of Ganduqing granules in the treatment of the common cold will be observed. The primary outcome is the time to clearance of all symptoms. The secondary outcomes included the levels of IL-6, TNF-α, SOD, and MDA in the peripheral blood, time to disappearance of primary symptoms and secondary symptoms, clinical symptom remission rate, and change in TCM syndrome score.

Results

Sixty participants completed the study. Ganduqing granules showed a greater effect on the time to clearance of all symptoms (P < 0.0001), nasal discharge (P=0.0124), fatigue and lack of strength (P=0.0138), dryness of the pharynx (P < 0.0001), pharyngalgia or dysphagia (P < 0.0001), and expectoration (P < 0.0431) compared with the placebo group. Participants in the intervention group had a greater decrease of IL-6 levels compared with the placebo group (P < 0.007); similar results were observed for the SOD (P < 0.033). However, the change in TNF-α and MDA levels in the intervention group was not significantly different from the placebo group. In addition, participants in the intervention group had a greater decrease of TCM syndrome score compared with the placebo group (P < 0.040).

Conclusion

Ganduqing granules could improve common cold symptoms, shorten the disease course, attenuated inflammation and oxidative stress, and provided objective evidence for the efficacy and safety of a Chinese herbal medicine in treating the common cold.

[Bromhexine is a potential drug for COVID-19; From hypothesis to clinical trials]

COVID-19 (novel coronavirus disease 2019), caused by the SARS-CoV-2 virus, has various clinical manifestations and several pathogenic pathways. Although several therapeutic options have been used to control COVID-19, none of these medications have been proven to be a definitive cure. Transmembrane serine protease 2 (TMPRSS2) is a protease that has a key role in the entry of SARS-CoV-2 into host cells. Following the binding of the viral spike (S) protein to the angiotensin-converting enzyme 2 (ACE2) receptors of the host cells, TMPRSS2 processes and activates the S protein on the epithelial cells. As a result, the membranes of the virus and host cell fuse. Bromhexine is a specific TMPRSS2 inhibitor that potentially inhibits the infectivity cycle of SARS-CoV-2. Moreover, several clinical trials are evaluating the efficacy of bromhexine in COVID-19 patients. The findings of these studies have shown that bromhexine is effective in improving the clinical outcomes of COVID-19 and has prophylactic effects by inhibiting TMPRSS2 and viral penetration into the host cells. Bromhexine alone cannot cure all of the symptoms of SARS-CoV-2 infection. However, it could be an effective addition to control and prevent the disease progression along with other drugs that are used to treat COVID-19. Further studies are required to investigate the efficacy of bromhexine in COVID-19.

Crosstalk between estrogen, dendritic cells, and SARS-CoV-2 infection

The novel coronavirus disease 2019 (Covid-19) first appeared in Wuhan and has so far killed more than four million people worldwide. Men are more affected than women by Covid-19, but the cellular and molecular mechanisms behind these differences are largely unknown. One plausible explanation is that differences in sex hormones could partially account for this distinct prevalence in both sexes. Accordingly, several papers have reported a protective role of 17β-estradiol during Covid-19, which might help explain why women appear less likely to die from Covid-19 than men. 17β-estradiol is the predominant and most biologically active endogenous estrogen, which signals through estrogen receptor α, estrogen receptor β, and G protein-coupled estrogen receptor 1. These receptors are expressed in mature cells from the innate and the adaptive immune system, particularly on dendritic cells (DCs), suggesting that estrogens could modulate their effector functions. DCs are the most specialized and proficient antigen-presenting cells, acting at the interface of innate and adaptive immunity with a powerful capacity to prime antigen-specific naive CD8+ T cells. DCs are richly abundant in the lung where they respond to viral infection. A relative increase of mature DCs in broncho-alveolar lavage fluids from Covid-19 patients has already been reported. Here we will describe how SARS-CoV-2 acts on DCs, the role of estrogen on DC immunobiology, summarise the impact of sex hormones on the immune response against Covid-19, and explore clinical trials regarding Covid-19.

Plant-Based Support of Respiratory Health during Viral Outbreaks

Respiratory viruses are linked to major epidemic events that have plagued humans through recorded history and possibly much earlier, ranging from common colds, influenza, and coronavirus infections to measles. However, difficulty in developing effective pharmaceutical solutions to treat infected individuals has hindered efforts to manage and minimize respiratory viral outbreaks and the associated mortality. Here we highlight a series of botanical interventions with different and often overlapping putative mechanisms of action to support the respiratory system, for which the bioactive pharmacophore was suggested and the initial structure-activity relationships have been explored (Bupleurum spp., Glycyrrhiza spp., Andrographis spp.), have been proposed with uncertainty (Echinacea spp., Zingiber spp., Verbascum spp., Marrubium spp.), or remained to be elucidated (Sambucus spp., Urtica spp.). Investigating these metabolites and their botanical sources holds potential to uncover new mediators of the respiratory health outcomes as well as molecular targets for future break-through therapeutic interventions targeting respiratory viral outbreaks.

Modulation of neutrophil (dys)function by Ayurvedic herbs and its potential influence on SARS-CoV-2 infection

For centuries, traditional medicines of Ayurveda have been in use to manage infectious and non-infectious diseases. The key embodiment of traditional medicines is the holistic system of approach in the management of human diseases. SARS-CoV-2 (COVID-19) infection is an ongoing pandemic, which has emerged as the major health threat worldwide and is causing significant stress, morbidity and mortality. Studies from the individuals with SARS-CoV-2 infection have shown significant immune dysregulation and cytokine overproduction. Neutrophilia and neutrophil to lymphocyte ratio has been correlated to poor outcome due to the disease. Neutrophils, component of innate immune system, upon stimulation expel DNA along with histones and granular proteins to form extracellular traps (NETs). Although, these DNA lattices possess beneficial activity in trapping and eliminating pathogens, NETs may also cause adverse effects by inducing immunothrombosis and tissue damage in diseases including Type 2 Diabetes and atherosclerosis. Tissues of SARS-CoV-2 infected subjects showed microthrombi with neutrophil-platelet infiltration and serum showed elevated NETs components, suggesting large involvement and uncontrolled activation of neutrophils leading to pathogenesis and associated organ damage. Hence, traditional Ayurvedic herbs exhibiting anti-inflammatory and antioxidant properties may act in a manner that might prove beneficial in targeting over-functioning of neutrophils and there by promoting normal immune homeostasis. In the present manuscript, we have reviewed and discussed pathological importance of NETs formation in SARS-CoV-2 infections and discuss how various Ayurvedic herbs can be explored to modulate neutrophil function and inhibit NETs formation in the context of a) anti-microbial activity to enhance neutrophil function, b) immunomodulatory effects to maintain neutrophil mediated immune homeostasis and c) to inhibit NETs mediated thrombosis.

New prophylaxis regimen for SARS-CoV-2 infection in health professionals with low doses of hydroxychloroquine and bromhexine: a randomised, double-blind placebo clinical trial (ELEVATE Trial)

INTRODUCTION

SARS-CoV-2 infection in Mexico has caused ~2.7 million confirmed cases; around 20%-25% of health workers will be infected by the virus at their workplace, with approximately 4.4% of mortality. High infectivity of SARS-CoV-2 is related with cell entry mechanism, through the ACE receptor. SARS-CoV-2 requires transmembrane protease serine 2 to cleave its spike glycoprotein and ensure fusion of host cell and virus membrane. We propose studying prophylactic treatment with hydroxychloroquine (HCQ) and bromhexine (BHH), which have been shown to be effective in preventing SARS-CoV-2 infection progression when administered in early stages. The aim of this study is to assess the efficacy of HCQ and BHH as prophylactic treatments for SARS-CoV-2 infection in healthy health workers exposed to the virus.

METHODS AND ANALYSIS

Double-blind randomised clinical trial, with parallel allocation at a 1:1 ratio with placebo, of low doses of HCQ plus BHH, for 60 days. Study groups will be defined as follows: (1) HCQ 200 mg/day+BHH 8 mg/8 hours versus (2) HCQ placebo plus BHH placebo. Primary endpoint will be efficacy of both interventions for the prevention of SARS-CoV-2 infection, determined by the risk ratio of infected personnel and the absolute risk. At least a 16% reduction in absolute risk is expected between the intervention and placebo groups; a minimum of 20% infection is expected in the placebo group. The sample size calculation estimated a total of 214 patients assigned: two groups of 107 participants each.

ETHICS AND DISSEMINATION

This protocol has been approved by the local Medical Ethics Committee (National Institute of Rehabilitation 'Luis Guillermo Ibarra Ibarra', approval number INRLGII/25/20) and by the Federal Commission for Protection against Sanitary Risks (COFEPRIS, approval number 203 300 410A0058/2020). The results of the study will be submitted for publication in peer-reviewed journals and disseminated through conferences.

TRIAL REGISTRATION NUMBER

NCT04340349.

Development and Validation of Two Novel Chromatographic Methods: HPTLC and HPLC for Determination of Bromhexine Hydrochloride in Presence of Its Two Impurities

Two simple, sensitive and validated chromatographic methods were developed for quantitative determination of bromhexine hydrochloride (BHX) in presence of its major impurities, impurity B (IMB) and impurity C (IMC), as specified by British Pharmacopoeia. First method (I) was high-performance thin layer chromatography-densitometry at which the chromatographic separation was performed using silica gel plates and developing system consisted of hexane:acetone:ammonia solution (9:0.5:0.08, by volume) with ultraviolet scanning at 240 nm and linearity was achieved in the ranges of 0.40-10.00, 0.20-2.00 and 0.20-2.00 μg/band of BHX, IMB and IMC, respectively. Also, second chromatographic method (II) was high-performance liquid chromatography (HPLC) where the separation was carried out on C18 column at isocratic mode at flow rate 1.5 mL/min. The mobile phase consisted of methanol:water (90:10, v/v) adjusted to pH 2.5 with O-phosphoric acid and temperature was adjusted to 40°C. The scanning wavelength was 240 nm. The chromatographic run time was 6 min. Linearity of this method was achieved in the ranges of 4.00-40.00, 0.20-10.00 and 0.50-10.00 μg/mL for BHX, IMB and IMC, respectively. The validation of these chromatographic methods was made according to International Conference on Harmonization guidelines. These methods were successfully applied for determination of BHX in its pharmaceutical formulation. Also, statistical comparison was attained between the developed methods and the reported HPLC method using Student's t-test and F-test, and the obtained results showed that there was not any significant difference between them concerning with accuracy and precision.

Bromhexine and its fumarate salt: Crystal structures, Hirshfeld surfaces and dissolution study

Bromhexine is an expectorant drug repurposing as a TMPRSS2 inhibitor, which has also been proposed for potential treatment in COVID-19 infection. Multicomponent crystal strategy has been applied in bromhexine to improve its poor solubility, which limits its bioavailability and efficacy. A new bromhexine crystal and its fumarate salt crystal have been successfully obtained by slow evaporation technique. Both compounds have been characterized by X-ray single-crystal diffraction, TGA and FT-IR spectroscopy. Hirshfeld surface analysis has been carried out to further quantify the patterns of intermolecular interactions. Compared with bromhexine, the multicomponent crystal with pharmaceutically acceptable conformer of fumaric acid shows improved thermal stability and solubility in water.

Targeting the intestinal TMPRSS2 protease to prevent SARS-CoV-2 entry into enterocytes-prospects and challenges

The transmembrane protease serine 2 (TMPRSS2) is a membrane anchored protease that primarily expressed by epithelial cells of respiratory and gastrointestinal systems and has been linked to multiple pathological processes in humans including tumor growth, metastasis and viral infections. Recent studies have shown that TMPRSS2 expressed on cell surface of host cells could play a crucial role in activation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein which facilitates the rapid early entry of the virus into host cells. In addition, direct suppression of TMPRSS2 using small drug inhibitors has been demonstrated to be effective in decreasing SARS-CoV-2 infection in vitro, which presents TMPRSS2 protease as a potential therapeutic strategy for SARS-CoV-2 infection. Recently, SARS-CoV-2 has been shown to be capable of infecting gastrointestinal enterocytes and to provoke gastrointestinal disorders in patients with COVID-19 disease, which is considered as a new transmission route and target organ of SARS-CoV-2. In this review, we highlight the biochemical properties of TMPRSS2 protease and discuss the potential targeting of TMPRSS2 by inhibitors to prevent the SARS-CoV-2 spreading through gastro-intestinal tract system as well as the hurdles that need to be overcome.

[Results of Open-Label non-Randomized Comparative Clinical Trial: "BromhexIne and Spironolactone for CoronаvirUs Infection requiring hospiTalization (BISCUIT)]

Introduction The aim of this study was to assess the efficacy and safety of a combination of bromhexine at a dose of 8 mg 4 times a day and spironolactone 50 mg per day in patients with mild and moderate COVID 19.Material and methods It was an open, prospective comparative non-randomized study. 103 patients were included (33 in the bromhexine and spironolactone group and 70 in the control group). All patients had a confirmed 2019 novel coronavirus infection (COVID 19) based on a positive polymerase chain reaction (PCR) for SARS-CoV-2 virus RNA and/or a typical pattern of viral pneumonia on multispiral computed tomography. The severity of lung damage was limited to stage I-II, the level of CRP should not exceed 60 mg / dL and SO2 in the air within 92-98%. The duration of treatment is 10 days.Results The decrease in scores on the SHOKS-COVID scale, which, in addition to assessing the clinical status, the dynamics of CRP (a marker of inflammation), D-dimer (a marker of thrombus formation), and the degree of lung damage on CT (primary endpoint) was statistically significant in both groups and differences between them was not identified. Analysis for the group as a whole revealed a statistically significant reduction in hospitalization time from 10.4 to 9.0 days (by 1.5 days, p=0.033) and fever time from 6.5 to 3.9 days (by 2.5 days, p&lt;0.001). Given the incomplete balance of the groups, the main analysis included 66 patients who were match with using propensity score matching. In matched patients, temperature normalization in the bromhexine/spironolactone group occurred 2 days faster than in the control group (p=0.008). Virus elimination by the 10th day was recorded in all patients in the bromhexine/spironolactone group; the control group viremia continued in 23.3% (p=0.077). The number of patients who had a positive PCR to the SARS-CoV-2 virus on the 10th day of hospitalization or longer (≥10 days) hospitalization in the control group was 20/21 (95.2%), and in the group with bromhexine /spironolactone -14/24 (58.3%), p=0.012. The odds ratio of having a positive PCR or more than ten days of hospitalization was 0.07 (95% CI: 0.008 - 0.61, p=0.0161) with bromhexine and spironolactone versus controls. No side effects were reported in the study group.Conclusion The combination of bromhexine with spironolactone appeared effective in treating a new coronavirus infection by achieving a faster normalization of the clinical condition, lowering the temperature one and a half times faster, and reducing explanatory combine endpoint the viral load or long duration of hospitalization (≥ 10 days).

Pharmacological treatments of COVID-19

The viral infection due to the new coronavirus or coronavirus disease 2019 (COVID-19), which was reported for the first time in December 2019, was named by the World Health Organization (WHO) as Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV2), because of the very similar genome and also its related symptoms to SARS-CoV1. The ongoing COVID-19 pandemic with significant mortality, morbidity, and socioeconomic impact is considered by the WHO as a global public health emergency. Since there is no specific treatment available for SARS-CoV2 infection, and or COVID-19, several clinical and sub-clinical studies are currently undertaken to find a gold-standard therapeutic regimen with high efficacy and low side effect. Based on the published scientific evidence published to date, we summarized herein the effects of different potential therapies and up-to-date clinical trials. The review is intended to help readers aware of potentially effective COVID-19 treatment and provide useful references for future studies.

Comparison of Bromhexine and its Active Metabolite - Ambroxol as Potential Analgesics Reducing Oxaliplatin-induced Neuropathic Pain - Pharmacodynamic and Molecular Docking Studies

BACKGROUND

Painful peripheral neuropathy is a dose-limiting adverse effect of the antitumor drug oxaliplatin. The main symptoms of neuropathy: tactile allodynia and cold hyperalgesia, appear in more than 80% of patients on oxaliplatin therapy and are due to the overexpression of neuronal sodium channels (Navs) and neuroinflammation.

OBJECTIVE

This study assessed antiallodynic and antihyperalgesic properties of two repurposed drugs with antiinflammatory and Nav-blocking properties (bromhexine and its pharmacologically active metabolite - ambroxol) in a mouse model of neuropathic pain induced by oxaliplatin. Using molecular docking techniques, we predicted targets implicated in the observed in vivo activity of bromhexine.

METHODS

Oxaliplatin (a single intraperitoneal dose of 10 mg/kg) induced tactile allodynia and cold hyperalgesia in CD-1 mice and the effectiveness of single-dose or repeated-dose bromhexine and ambroxol to attenuate pain hypersensitivity was assessed in von Frey and cold plate tests. Additionally, Veber analysis and molecular docking experiments of bromhexine on mouse (m) and human (h) Nav1.6-1.9 were carried out.

RESULTS

At the corresponding doses, ambroxol was more effective than bromhexine as an antiallodynic agent. However, at the dose of 150 mg/kg, ambroxol induced motor impairments in mice. Repeated-dose bromhexine and ambroxol partially attenuated the development of late-phase tactile allodynia in oxaliplatin-treated mice. Only 7-day administration of bromhexine attenuated the development of late-phase cold hyperalgesia. Bromhexine was predicted to be a strong inhibitor of mNav1.6, mNav1.7, mNav1.9, and hNav1.7-hNav1.9.

CONCLUSION

The conversion of bromhexine to other than ambroxol active metabolites should be considered when interpreting some of its in vivo effects. Nav-blocking properties of bromhexine (and previously also predicted for ambroxol) might underlie its ability to attenuate pain caused by oxaliplatin.

Current approaches used in treating COVID-19 from a molecular mechanisms and immune response perspective

Coronavirus disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was declared by the World Health Organization (WHO) as a global pandemic on March 11, 2020. SARS-CoV-2 targets the respiratory system, resulting in symptoms such as fever, headache, dry cough, dyspnea, and dizziness. These symptoms vary from person to person, ranging from mild to hypoxia with acute respiratory distress syndrome (ARDS) and sometimes death. Although not confirmed, phylogenetic analysis suggests that SARS-CoV-2 may have originated from bats; the intermediary facilitating its transfer from bats to humans is unknown. Owing to the rapid spread of infection and high number of deaths caused by SARS-CoV-2, most countries have enacted strict curfews and the practice of social distancing while awaiting the availability of effective U.S. Food and Drug Administration (FDA)-approved medications and/or vaccines. This review offers an overview of the various types of coronaviruses (CoVs), their targeted hosts and cellular receptors, a timeline of their emergence, and the roles of key elements of the immune system in fighting pathogen attacks, while focusing on SARS-CoV-2 and its genomic structure and pathogenesis. Furthermore, we review drugs targeting COVID-19 that are under investigation and in clinical trials, in addition to progress using mesenchymal stem cells to treat COVID-19. We conclude by reviewing the latest updates on COVID-19 vaccine development. Understanding the molecular mechanisms of how SARS-CoV-2 interacts with host cells and stimulates the immune response is extremely important, especially as scientists look for new strategies to guide their development of specific COVID-19 therapies and vaccines.

Ambroxol Hydrochloride Inhibits the Interaction between Severe Acute Respiratory Syndrome Coronavirus 2 Spike Protein's Receptor Binding Domain and Recombinant Human ACE2

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), enters the host cells through two main pathways, both involving key interactions between viral envelope-anchored spike glycoprotein of the novel coronavirus and the host receptor, angiotensin-converting enzyme 2 (ACE2). To date, SARS-CoV-2 has infected up to 26 million people worldwide; yet, there is no clinically approved drug or vaccine available. Therefore, a rapid and coordinated effort to re-purpose clinically approved drugs that prevent or disrupt these critical entry pathways of SARS-CoV-2 spike glycoprotein interaction with human ACE2, could potentially accelerate the identification and clinical advancement of prophylactic and/or treatment options against COVID-19, thus providing possible countermeasures against viral entry, pathogenesis and survival. Herein, we discovered that Ambroxol hydrochloride (AMB), and its progenitor, Bromhexine hydrochloride (BHH), both clinically approved drugs are potent effective modulators of the key interaction between the receptor binding domain (RBD) of SARS-CoV-2 spike protein and human ACE2. We also found that both compounds inhibited SARS-CoV-2 infection-induced cytopathic effect at micromolar concentrations. Therefore, in addition to the known TMPRSS2 activity of BHH; we report for the first time that the BHH and AMB pharmacophore has the capacity to target and modulate yet another key protein-protein interaction essential for the two known SARS-CoV-2 entry pathways into host cells. Altogether, the potent efficacy, excellent safety and pharmacologic profile of both drugs along with their affordability and availability, makes them promising candidates for drug repurposing as possible prophylactic and/or treatment options against SARS-CoV-2 infection.

Evaluating the efficacy and safety of bromhexine hydrochloride tablets in treating pediatric COVID-19: A protocol for meta-analysis and systematic review

BACKGROUND

Bromhexine hydrochloride tablets may be effective in the treatment of Coronavirus disease 2019 (COVID-19) in children. This study will further evaluate the efficacy and safety of bromhexine hydrochloride tablets in the treatment of COVID-19 in children.

METHODS

The following electronic databases will be searched, with all relevant randomized controlled trials (RCTs) up to August 2020 to be included: PubMed, Embase, Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), the Chongqing VIP China Science and Technology Database (VIP), Wanfang, the Technology Periodical Database, and the Chinese Biomedical Literature Database (CBM). As well as the above, Baidu, the International Clinical Trials Registry Platform (ICTRP), Google Scholar, and the Chinese Clinical Trial Registry (ChiCTR) will also be searched to obtain more comprehensive data. Besides, the references of the included literature will also be traced to supplement our search results and to obtain all relevant literature.

RESULTS

This systematic review will evaluate the current status of bromhexine hydrochloride in the treatment of COVID-19 in children, to evaluate its efficacy and safety.

CONCLUSION

This study will provide the latest evidence for evaluating the efficacy and safety of bromhexine hydrochloride in the treatment of COVID-19 in children.

PROSPERO REGISTRATION NUMBER

CRD42020199805.

ETHICS AND DISSEMINATION

The private information of individuals will not be published. This systematic review will also not involve endangering participant rights. Ethical approval is not available. The results may be published in peer-reviewed journals or disseminated at relevant conferences.

[Combination therapy at an early stage of the novel coronavirus infection (COVID-19). Case series and design of the clinical trial "BromhexIne and Spironolactone for CoronаvirUs Infection requiring hospiTalization (BISCUIT)"]

The article focuses on effective treatment of the novel coronavirus infection (COVID-19) at early stages and substantiates the requirement for antiviral therapy and for decreasing the viral load to prevent the infection progression. The absence of a specific antiviral therapy for the SARS-CoV-2 virus is stated. The authors analyzed results of early randomized studies using lopinavir/ritonavir, remdesivir, and favipiravir in COVID-19 and their potential for the treatment of novel coronavirus infection. Among the drugs blocking the virus entry into cells, the greatest attention was paid to the antimalaria drugs, chloroquine and hydroxychloroquine. The article addresses in detail ineffectiveness and potential danger of hydroxychloroquine, which demonstrated neither a decrease in the time of clinical recovery nor any improvement of prognosis for patients with COVID-19. The major objective was substantiating a possible use of bromhexine, a mucolytic and anticough drug, which can inhibit transmembrane serin protease 2 required for entry of the SARS-CoV-2 virus into cells. Spironolactone may have a similar feature. Due to its antiandrogenic effects, spironolactone can inhibit X-chromosome-related synthesis of ACE-2 receptors and activation of transmembrane serin protease 2. In addition to slowing the virus entry into cells, spironolactone decreases severity of fibrosis in different organs, including the lungs. The major part of the article addresses clinical examples of managing patients with COVID-19 at the University Clinic of the Medical Research and Educational Centre of the M. V. Lomonosov Moscow State University, including successful treatment with schemes containing bromhexine and spironolactone. In conclusion, the authors described the design of a randomized, prospective BISCUIT study performed at the University Clinic of the M. V. Lomonosov Moscow State University with an objective of evaluating the efficacy of this scheme.

Potential Anti-COVID-19 Therapeutics that Block the Early Stage of the Viral Life Cycle: Structures, Mechanisms, and Clinical Trials

The ongoing pandemic of coronavirus disease-2019 (COVID-19) is being caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The disease continues to present significant challenges to the health care systems around the world. This is primarily because of the lack of vaccines to protect against the infection and the lack of highly effective therapeutics to prevent and/or treat the illness. Nevertheless, researchers have swiftly responded to the pandemic by advancing old and new potential therapeutics into clinical trials. In this review, we summarize potential anti-COVID-19 therapeutics that block the early stage of the viral life cycle. The review presents the structures, mechanisms, and reported results of clinical trials of potential therapeutics that have been listed in clinicaltrials.gov. Given the fact that some of these therapeutics are multi-acting molecules, other relevant mechanisms will also be described. The reviewed therapeutics include small molecules and macromolecules of sulfated polysaccharides, polypeptides, and monoclonal antibodies. The potential therapeutics target viral and/or host proteins or processes that facilitate the early stage of the viral infection. Frequent targets are the viral spike protein, the host angiotensin converting enzyme 2, the host transmembrane protease serine 2, and clathrin-mediated endocytosis process. Overall, the review aims at presenting update-to-date details, so as to enhance awareness of potential therapeutics, and thus, to catalyze their appropriate use in combating the pandemic.

Effect of different herbal preparations on experimental viral respiratory complex of broilers: clinical, pathological and ciliary activity aspects

Introduction: Despite the extensive use of herbal preparations for treatment of viral respiratory diseases in poultry, few studies have analyzed the effectiveness of these products. This study aimed to evaluate the effects of three different herbal respiratory symptom relieving agents in broiler chickens experimentally infected with H9N2 avian influenza (AI) and infectious bronchitis (IB) viruses. Methods: A total of 175 broiler chickens were randomly assigned into 5 equal groups. Negative control (NC) group remained intact while others received H9N2-AI and IB viruses. Treatment groups (G1-G3) but not positive control (PC) birds were treated with three different herbal agents containing menthol. Clinical and pathological aspects were evaluated during the experiment. Results: Administration of these agents to challenged chickens not only did not notably decrease clinical severity, gross and histopathological lesions, but also markedly increased mortality rate in treated groups. In dead cases, cast/plug formation was a prominent feature in the trachea. Treatment with herbal agents induced an increase of more than twofold in the number of goblet cells compared to PC group. Significant ciliostasis was observed in all challenged groups regardless of treatment, while ciliary activity was not changed statistically in comparison with the mean values of PC. Conclusion: In this study administration of herbal preparations adversely affected the tracheal epithelium via enhancement of goblet cell hyperplasia. It appears that hyper-secretion of mucosa along with ciliary incompetence causes mucus stagnation followed by tracheal or bronchial obstruction and death. These findings necessitate cautious use of these products.

An overview of efficacy and safety of ambroxol for the treatment of acute and chronic respiratory diseases with a special regard to children

Introduction: Ambroxol (2-amino-3,5-dibromo-N-[trans-4-hydroxycyclohexyl]benzylamine), an over-the-counter product, is a mucoactive agent and has been used widely to treat both acute and chronic respiratory diseases since 1978. This review aims to provide an overview of the clinical evidence available on the use of ambroxol in children with acute and chronic respiratory diseases. Data for this review were obtained from both published and unpublished clinical studies, and real-world evidence studies. Although conducted prior to the introduction of Good Clinical Practice (GCP), these studies, representing almost 1,300 pediatric patients, report strong clinical outcomes following the use of ambroxol in pediatric patients. Furthermore, efficacy findings were consistent irrespective of age, including for patients as young as 1 month old. Additionally, the majority of studies found ambroxol to be well tolerated in children. Taken together, the clinical evidence for ambroxol shows treatment effects that offer significant benefits to pediatric patients for its licensed use as a secretolytic therapy in acute and chronic bronchopulmonary disorders associated with abnormal mucus secretion and impaired mucus transport. The findings from this review indicate that ambroxol, for its intended over-the-counter indications, is both efficacious and well tolerated in children and that the favorable benefit/risk profile of ambroxol reported in adults extends to the pediatric population, starting from early infancy, with acute and chronic respiratory diseases.

4-Amino-5-{[cyclohexyl(methyl)amino]methyl}isophthalonitrile

The title compound, C16H20N4, was synthesized by cyanation of bromhexine. The compound crystallizes with two unique molecules in the asymmetric unit. The substituted aniline and cyclohexane rings are inclined to one another by 37.26 (6)° in one molecule and by 22.84 (7)° in the other. In the crystal packing, intra- and intermolecular N—H...N hydrogen bonds and an intermolecular C—H...N contact were observed.

Bromhexine elevates REP2 expression to stimulate secretion from human primary conjunctiva fornix epithelial cells

Bromhexine was reported to relieve the symptoms of Sjogren Syndrome at an early stage. However, the underlying mechanism remains unclear. Here, we administered bromhexine at low doses in human primary conjunctival fornix epithelial cells, and found it stimulated MUC5AC secretion and lipid droplet production. Expression of the metabolism-related gene CHML was also upregulated by bromhexine treatment, and REP2, the protein produced by the CHML gene, was induced. These results suggest that bromhexine is a potential candidate eye drop drug for the treatment of multiple types of dry eye disease, not only limited to the treatment of dry eyes in Sjogren Syndrome.

Mucoactive Agents in the Therapy of Upper Respiratory Airways Infections: Fair to Describe Them Just as Mucoactive?

Background

Upper and lower respiratory tract infections are common conditions for which medical advice is sought, and their management relies on the use of prescription and over-the-counter (OTC) medicines. Ambroxol, bromhexine, carbocysteine, erdosteine, N-acetyl cysteine (NAC), and sobrerol are mucoactive agents for which clinical trials have been conducted, have been awarded well-established status by regulatory authorities, and are available as OTC or prescription products.

Objective

To briefly review the evidence-based efficacy and safety of these substances in the therapy of upper respiratory airways infections.

Methods

We conducted searches in MEDLINE and other databases for clinical trials and reviews done on the efficacy and safety of ambroxol, bromhexine, carbocysteine, erdosteine, NAC, and sobrerol.

Results

Clinical trials have shown that these mucolytics have an important place in the relief of cough symptoms by easing the elimination of mucus. All drugs have shown comparable efficacy in the symptomatic treatment of productive cough, with some shared characteristics and some specific features.

Conclusions and relevance

All mucolytics reviewed have a good safety profile, although some precautions should be taken when using ambroxol and bromhexine, and the use of NAC and carbocysteine should be monitored in special patient groups. Overall, however, the available evidence from randomised, controlled, and observational trials, as well as pragmatic, real-life experience, suggests that these products are useful in the therapy of upper respiratory airways infections, including bronchitis, sinusitis, and rhinosinusitis.

Current and future pharmacotherapy options for non-cystic fibrosis bronchiectasis

INTRODUCTION

In recent years, there has been an increasing number of clinical trials investigating the effect of pharmacological treatments on patients with bronchiectasis. Areas covered: This review provides an overview of current drugs used in bronchiectasis patients as well as those that could make a future contribution to the management of this disease. Expert commentary: Bronchiectasis is a very heterogeneous disease, so it can be studied from a phenotypic standpoint and its pathophysiological mechanisms (endotypes) can be defined. This provides an interesting field of research as it enables the identification of patients suitable for inclusion in specific clinical trials on new drugs.

Ductal Mucus Obstruction and Reduced Fluid Secretion Are Early Defects in Chronic Pancreatitis

Objective: Defective mucus production in the pancreas may be an important factor in the initiation and progression of chronic pancreatitis (CP), therefore we aimed to (i) investigate the qualitative and quantitative changes of mucus both in human CP and in an experimental pancreatitis model and (ii) to correlate the mucus phenotype with epithelial ion transport function.

Design: Utilizing human tissue samples and a murine model of cerulein induced CP we measured pancreatic ductal mucus content by morphometric analysis and the relative expression of different mucins in health and disease. Pancreatic fluid secretion in CP model was measured in vivo by magnetic resonance cholangiopancreatography (MRCP) and in vitro on cultured pancreatic ducts. Time-changes of ductal secretory function were correlated to those of the mucin production.

Results: We demonstrate increased mucus content in the small pancreatic ducts in CP. Secretory mucins MUC6 and MUC5B were upregulated in human, Muc6 in mouse CP. In vivo and in vitro fluid secretion was decreased in cerulein-induced CP. Analysis of time-course changes showed that impaired ductal ion transport is paralleled by increased Muc6 expression.

Conclusion: Mucus accumulation in the small ducts is a combined effect of mucus hypersecretion and epithelial fluid secretion defect, which may lead to ductal obstruction. These results suggest that imbalance of mucus homeostasis may have an important role in the early-phase development of CP, which may have novel diagnostic and therapeutic implications.