Aprepitant for Cough in Lung Cancer. A Randomized Placebo-controlled Trial and Mechanistic Insights

Cough in idiopathic pulmonary fibrosis: what is new

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and fatal interstitial fibrosing disease and, despite some well-known risk factors, its cause is still unknown. Cough is experienced by most patients and is commonly chronic and refractory, having a significant impact on quality of life. Its aetiology is complex, combining factors related to interstitial lung disease (ILD) such as an increased sensitivity of cough-sensitive nerves, structural lung changes and inflammation, genetic factors, several comorbidities and medication-adverse effects. Despite the therapeutic advancements in IPF over the past decade with the introduction of antifibrotic drugs that slow disease progression, effective treatment options for cough in IPF remain unavailable. Cough management often relies on empirical approaches based on studies involving chronic cough patients of unspecified causes and ILD physicians' personal experiences. Different classes of medications have been tried over time and, more recently, the focus has turned to neuromodulators and opioids, but several studies have shown suboptimal efficacy in cough. On the other hand, these drugs are associated with significant physical, psychological and economic burdens. However, the future brings us hope to the extent that most current ongoing clinical trials are using new molecules and some have demonstrated promising antitussive effects. This review aims to provide a practical guide to understanding and managing cough in IPF patients, presenting pharmacological and non-pharmacological approaches over time, as well as those treatments that are currently being investigated in clinical settings.

Cough and itch: Common mechanisms of irritation in the throat and skin

Cough and itch are protective mechanisms in the body. Cough occurs as a reflex motor response to foreign body inhalation, while itch is a sensation that similarly evokes a scratch response to remove irritants from the skin. Both cough and itch can last for sustained periods, leading to debilitating chronic disorders that negatively impact quality of life. Understanding the parallels and differences between chronic cough and chronic itch may be paramount to developing novel therapeutic approaches. In this article, we identify connections in the mechanisms contributing to the complex cough and scratch reflexes and summarize potential shared therapeutic targets. An online search was performed using various search engines, including PubMed, Web of Science, Google Scholar, and ClinicalTrials.gov from 1983 to 2024. Articles were assessed for quality, and those relevant to the objective were analyzed and summarized. The literature demonstrated similarities in the triggers, peripheral and central nervous system processing, feedback mechanisms, immunologic mediators, and receptors involved in the cough and itch responses, with the neuronal sensitization processes exhibiting the greatest parallels between cough and itch. Given the substantial impact on quality of life, novel therapies targeting similar neuroimmune pathways may apply to both itch and cough and provide new avenues for enhancing their management.

Pregabalin for chronic cough due to lung cancer: randomized, double-blind, placebo-controlled trial

BACKGROUND

Developing effective therapies for cough in lung cancer is an unmet need Neuromodulators like pregabalin may act centrally as cough suppressants.

METHODS

Randomized double-blind placebo-controlled study in patients with locally advanced/metastatic lung cancer and at least 2 weeks of moderate or severe cough. Randomization was 1:1 to pregabalin 300 mg orally daily or matching placebo, both administered for 9 weeks. Primary endpoint was the change in cough severity as measured by the difference in VAS scores.

RESULTS

Between Jul 2022 and Dec 2023, we enrolled 166 patients: 83 to each arm. Baseline cough severity was grade 2 in 128 (77.1%) and grade 3 in 38 (22.9%) patients; median cough duration was 12 weeks (IQR, 6-20). Systemic cancer-directed therapy was started in 78 (94.0%) and 72 (86.7%) patients in the pregabalin and placebo arms, respectively; P = 0.187. The mean (SD) VAS score (in mm) decreased from 71.58 (14.99) at baseline, to 45.54 (26.60) on day 7, and 22.27 (24.20) by week 9 in the pregabalin arm; and 71.75 (17.58), 46.35 (25.00), and 23.08 (22.42), respectively in the placebo arm; P = 0.877.

CONCLUSION

Pregabalin does not significantly decrease cough in patients with lung cancer. Systemic cancer-directed therapy is the most effective antitussive.

CLINICAL TRIAL REGISTRATION

Name of the registry: Clinical Trials Registry India Registration number: CTRI/2020/11/029275 Website: www.ctri.nic.in.

Unravelling vagal hypersensitivity in chronic cough: A distinct disease

Chronic cough (CC) is a common but poorly understood disease that has a negative impact on quality of life. For years, clinicians have been trying to find the underlying diagnosis and using existing disease models to describe the patients' illness. This presents a confusing picture of CC. Most patients with CC present with hypersensitivity of the cough reflex, which is characterised by laryngeal paraesthesia and an increased response to the tussive stimuli or an innocuous stimulus that would not trigger coughing in healthy people. Recently, it has been proposed that CC is a unique disease characterised by vagal hypersensitivity that projects to the central nervous system altering responsiveness. The evidence supports the hypothesis that CC is primarily a neurological disorder, consisting of different phenotypes.

What causes cough in pulmonary fibrosis, and how should we treat it?

PURPOSE OF REVIEW

To review the current understanding of the impact, mechanisms and treatments for cough in patients with interstitial lung disease (ILD). Evidence suggests that cough is a prevalent symptom in patients with ILD and has a significant impact on patients.

RECENT FINDINGS

There is increasing interest in the role of cough hypersensitivity as seen in chronic refractory cough in patients with ILD, and encouraging recent results suggest that ILD-associated cough responds to opiate therapy.

SUMMARY

Understanding the aetiology of cough in patients with ILD is crucial to continue to develop therapies which might be effective in reducing cough and increasing quality of life.

Drugs Targeting Cough Receptors: New Therapeutic Options in Refractory or Unexplained Chronic Cough

Refractory chronic cough is a disabling disease with very limited therapeutic options. A better understanding of cough pathophysiology has led to the development of emerging drugs targeting cough receptors. Recent strides have illuminated novel therapeutic avenues, notably centred on modulating transient receptor potential (TRP) channels, purinergic receptors, and neurokinin receptors. By modulating these receptors, the goal is to intervene in the sensory pathways that trigger cough reflexes, thereby providing relief without compromising vital protective mechanisms. These innovative pharmacotherapies hold promise for improvement of refractory chronic cough by offering improved efficacy and potentially mitigating adverse effects associated with current recommended treatments. A deeper comprehension of their precise mechanisms of action and clinical viability is imperative for optimising therapeutic interventions and elevating patient care standards in respiratory health. This review delineates the evolving landscape of drug development in this domain, emphasising the significance of these advancements in reshaping the paradigm of cough management.

Efficacy of acupuncture for a cough-related symptom cluster in patients with lung cancer: A randomized controlled trial

PURPOSE

This study was designed to evaluate the effect of acupuncture on cough, expectoration, and shortness of breath in lung cancer patients.

METHODS

Between December 2021 and June 2022, a total of 130 lung cancer patients were recruited, and they were split into control and intervention groups at random. Routine nursing was provided to the control group, whereas routine nursing with acupuncture using LU7 (Lie Que), LU9 (Tai Yuan), BL13 (Fei Shu), and BL20 (Pi Shu) was administered to the intervention group for 7 days. The severity of cough, expectoration, and shortness of breath was assessed 1 day before and after the interventions using the lung cancer-specific module of the MDASI. A two-way ANOVA was performed for group comparisons.

RESULTS

Compared with the control group, the symptoms of cough in the intervention group were significantly improved (F = 5.095, MD = -0.32, 95% CI, -0.59 to 0.04, P = 0.025), while expectoration (F = 0.626, MD = -0.11, 95% CI, -0.38 to 0.16, P = 0.430) and shortness of breath (F = 0.165, MD = -0.05, 95% CI, -0.27 to 0.18, P = 0.685) had no significant change. Cough also identified an obvious interaction effect (P = 0.014), and the post-intervention simple main effect test demonstrated a tangible difference between the two groups (MD = -0.66, 95% CI, -0.99 to 0.33, P < 0.001) post-intervention.

CONCLUSIONS

Acupuncture using LU7, LU9, BL13, and BL20 can relieve the cough of lung cancer patients, but not relieve expectoration and shortness of breath.

[Palliative aspects in pulmonary oncology]

Palliative medicine is an essential part in the treatment of patients with advanced or metastatic NSCLC. A structured palliative approach beginning from diagnoses improves quality of life and maybe even prolong survival. Besides symptom control, the disease trajectory and prognosis should regularly be re-evaluated and discussed with the patient and his loved ones.

Advances in the research and application of neurokinin-1 receptor antagonists

Recently, the substance P (SP)/neurokinin-1 receptor (NK-1R) system has been found to be involved in various human pathophysiological disorders including the symptoms of coronavirus disease 2019 (COVID-19). Besides, studies in the oncological field have demonstrated an intricate correlation between the upregulation of NK-1R and the activation of SP/NK-1R system with the progression of multiple carcinoma types and poor clinical prognosis. These findings indicate that the modulation of SP/NK-1R system with NK-1R antagonists can be a potential broad-spectrum antitumor strategy. This review updates the latest potential and applications of NK-1R antagonists in the treatment of human diseases and cancers, as well as the underlying mechanisms. Furthermore, the strategies to improve the bioavailability and efficacy of NK-1R antagonist drugs are summarized, such as solid dispersion systems, nanonization, and nanoencapsulation. As a radiopharmaceutical therapeutic, the NK-1R antagonist aprepitant was originally developed as radioligand receptor to target NK-1R-overexpressing tumors. However, combining NK-1R antagonists with other drugs can produce a synergistic effect, thereby enhancing the therapeutic effect, alleviating the symptoms, and improving patients quality of life in several diseases and cancers.

The Therapeutic Landscape in Chronic Cough

In recent years, there has been a substantial increase in the development of antitussive therapies and the first new therapy, gefapixant has been licenced in Europe. This review describes current unlicenced treatments for chronic cough and details treatments currently in development for refractory chronic cough and cough in idiopathic pulmonary fibrosis, as well as compounds previously explored.

TRPM8 inhibits substance P release from primary sensory neurons via PKA/GSK-3beta to protect colonic epithelium in colitis

Transient receptor potential melastatin 8 (TRPM8) is a cold sensory receptor in primary sensory neurons that regulates various neuronal functions. Substance P (SP) is a pro-inflammatory neuropeptide secreted by the neurons, and it aggravates colitis. However, the regulatory role of TRPM8 in SP release is still unclear. Our study aimed to investigate TRPM8's role in SP release from primary sensory neurons during colitis and clarify the effect of SP on colonic epithelium. We analyzed inflammatory bowel disease patients' data from the Gene Expression Omnibus dataset. Dextran sulfate sodium (DSS, 2.5%)-induced colitis in mice, mouse dorsal root ganglion (DRG) neurons, ND7/23 cell line, and mouse or human colonic organoids were used for this experiment. Our study found that TRPM8, TAC1 and WNT3A expression were significantly correlated with the severity of ulcerative colitis in patients and DSS-induced colitis in mice. The TRPM8 agonist (menthol) and the SP receptor antagonist (Aprepitant) can attenuate colitis in mice, but the effects were not additive. Menthol promoted calcium ion influx in mouse DRG neurons and inhibited the combination and phosphorylation of PKAca from the cAMP signaling pathway and GSK-3β from the Wnt/β-catenin signaling pathway, thereby inhibiting the effect of Wnt3a-driven β-catenin on promoting SP release in ND7/23 cells. Long-term stimulation with SP inhibited proliferation and enhanced apoptosis in both mouse and human colonic organoids. Conclusively, TRPM8 inhibits SP release from primary sensory neurons by inhibiting the interaction between PKAca and GSK-3β, thereby inhibiting the role of SP in promoting colonic epithelial apoptosis and relieving colitis.

Relationship between dyspnoea and related factors in patients with cancer: a cross-sectional study

OBJECTIVES

Dyspnoea is a common and distressing symptom in patients with cancer. We aimed to analyse the association between dyspnoea and related factors and to estimate their causal relationship.

METHODS

A cross-sectional study was conducted. Patients with cancer with dyspnoea and a mean Numerical Rating Scale (NRS) of ≥3 over 24 hours were enrolled at 10 institutions in Japan from December 2019 to February 2021. The outcomes included dyspnoea, cough and pain NRS over 24 hours, Eastern Cooperative Oncology Group Performance Status, Hospital Anxiety and Depression Scale, Somatosensory Amplification Scale, opioids for dyspnoea and respiratory failure. Path analyses were conducted to estimate the direct and indirect paths with reference to dyspnoea and related factors.

RESULTS

A total of 209 patients were enrolled and 208 patients were included in the analysis. Cough worsened dyspnoea (β=0.136), dyspnoea increased emotional distress (β=1.104), emotional distress increased somatosensory amplification (β=0.249) and somatosensory amplification worsened cough (β=0.053) according to path analysis.

CONCLUSION

There may be a vicious circle among dyspnoea and related factors: cough worsened dyspnoea, dyspnoea increased emotional distress, emotional distress increased somatosensory amplification and somatosensory amplification worsened cough. When treating dyspnoea in patients with cancer, managing these factors aimed at interrupting this vicious circle may be useful.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry (UMIN000038820).

Patient's experiences of coughing after lung cancer surgery: A multicenter qualitative study

PURPOSE

Cough is one of the most common symptoms after lung cancer surgery, which seriously affects the quality of life. Little research has been conducted on patient's experiences of cough following lung surgery. This study aimed to elucidate the experience of coughing after lung cancer surgery from the patient's perspective regarding symptoms and their impacts on daily life, as well as triggers and dealing strategies.

METHODS

Between June 2023 and July 2023, we conducted semi-structured interviews with patients from outpatient clinics of two hospitals who were pathologically diagnosed with lung cancer and experienced cough after surgery through convenience sampling. The interview recordings were transcribed and analyzed by two researchers. The traditional content analysis and thematic analysis were used to identify the common codes, subthemes, and themes.

RESULTS

A total of 28 participants were interviewed. The mean age of the participants was 55.21 years (range: 36-75 years), and 21 participants were female. Most patients (75%) were interviewed within 6 months of surgery. We identified five themes (accompanying symptoms, incentives, effects, solution, and information sources) and 12 subthemes (local symptoms, systemic symptoms, personal factors, external factors, emotion, relationship with others, reduced quality of life, medical measures, nonmedical measures, no measures, relatives and friends, and the Internet). Patients with lung cancer may experience various cough symptoms after surgery, which a variety of internal and external factors can trigger. The coughing imposes a double burden on the physical and psychological due to the negative emotions it provokes.

CONCLUSION

We generated a concept framework of cough after lung cancer surgery, providing a basis for further development of measurement tools from the patients' perspective. The lack of knowledge related to coughing highlights the need for adequate and timely health education and professional medical care.

Patient's experiences of coughing after lung cancer surgery: A multicenter qualitative study

Purpose

Cough is one of the most common symptoms after lung cancer surgery, which seriously affects the quality of life. Little research has been conducted on patient's experiences of cough following lung surgery. This study aimed to elucidate the experience of coughing after lung cancer surgery from the patient's perspective regarding symptoms and their impacts on daily life, as well as triggers and dealing strategies.

Methods

Between June 2023 and July 2023, we conducted semi‐structured interviews with patients from outpatient clinics of two hospitals who were pathologically diagnosed with lung cancer and experienced cough after surgery through convenience sampling. The interview recordings were transcribed and analyzed by two researchers. The traditional content analysis and thematic analysis were used to identify the common codes, subthemes, and themes.

Results

A total of 28 participants were interviewed. The mean age of the participants was 55.21 years (range: 36–75 years), and 21 participants were female. Most patients (75%) were interviewed within 6 months of surgery. We identified five themes (accompanying symptoms, incentives, effects, solution, and information sources) and 12 subthemes (local symptoms, systemic symptoms, personal factors, external factors, emotion, relationship with others, reduced quality of life, medical measures, nonmedical measures, no measures, relatives and friends, and the Internet). Patients with lung cancer may experience various cough symptoms after surgery, which a variety of internal and external factors can trigger. The coughing imposes a double burden on the physical and psychological due to the negative emotions it provokes.

Conclusion

We generated a concept framework of cough after lung cancer surgery, providing a basis for further development of measurement tools from the patients' perspective. The lack of knowledge related to coughing highlights the need for adequate and timely health education and professional medical care.

Effects of spray cryotherapy on cough receptors and airway microenvironment in a canine model of chronic bronchitis

The aim of this study was to explore the effects of spray cryotherapy (SCT) on cough receptors and airway microenvironment in a canine model of chronic bronchitis. We examined the expression of transient receptor potential vanilloid 1/4 (TRPV1/4) and the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) at the gene and protein levels before and after SCT. In addition, we explored whether TRPV1/4 could regulate inflammatory factors via mediator adenosine triphosphate (ATP). The levels of ATP and cytokines in alveolar lavage fluid and cell supernatant were measured using ELISA. SCT effectively downregulated the expression of TRPV1/4 and SP/CGRP in canine airway tissues with chronic bronchitis and reduced the levels of inflammatory mediators and cytokines that affect cough receptor sensitivity, achieving cough relief. TRPV1/4 - ATP - inflammatory cytokines axis has been demonstrated at the cellular level, which in turn modulate the milieu of the airways and promote the formation of a cough feedback loop. Our study has fully revealed the specific mechanism of SCT in treating cough in a canine model of chronic bronchitis, providing a solid theoretical basis for future clinical treatment.

Assessment and Management of Cough in Idiopathic Pulmonary Fibrosis: A Narrative Review

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal disease with an unknown cause. It is characterized by symptoms such as cough and breathlessness, which significantly impact patients' quality of life. Cough, in particular, has emerged as a burdensome symptom for individuals with IPF. The etiology of cough in IPF patients is believed to be complex, involving factors related to the disease itself, such as increased sensitivity of cough nerves, lung structural changes, inflammation, and genetic factors, as well as comorbidities and medication effects. Unfortunately, effective treatment options for cough in IPF remain limited, often relying on empirical approaches based on studies involving chronic cough patients in general and the personal experience of physicians. Medications such as opioids and neuromodulators are commonly prescribed but have shown suboptimal efficacy, imposing significant physical, psychological, and economic burdens on patients. However, there is hope on the horizon, as specific purinergic P2 receptor ligand-gated ion channel (P2X3) inhibitors have demonstrated promising antitussive effects in ongoing clinical trials. This review aims to provide a comprehensive overview of the evaluation and management of cough in IPF patients, as well as highlight emerging pharmacological and non-pharmacological approaches that target the cough reflex and are currently being investigated in clinical settings.

Cough medicines for children- time for a reality check

Cough medicines have been in use for over a century to treat the common and troublesome, but often helpful, symptoms of cough in children. They contain various combinations of "anti-tussive" drugs including opioids, antihistamines, herbal preparations, mucolytics, decongestants and expectorants. Whilst theoretically attractive for symptom relief when children are suffering, as time has passed these popular over the counter medicines have been shown to lack efficacy, delay more serious underlying diagnoses, and can cause complications and sometimes death. This has resulted in clinician concerns, a citizen petition to the American Food and Drug Association in 2007, some self-regulation from manufacturers and escalating restrictions on their use from regulatory agencies across the world over the last twenty years. This article will review the protective role of cough, juxtapose the conflicting treatment goals of suppressing a dry cough and promoting expectoration for a wet cough, consider the evidence basis for prescribing cough medicines in comparison to other more specific treatments such as for asthma [beta agonists] or infection [antibiotics], regulatory interventions, and conclude with the view that over counter cough medicines should not be used in children, especially young children.

Illuminating Airway Nerve Structure and Function in Chronic Cough

Airway nerves regulate vital airway functions including bronchoconstriction, cough, and control of respiration. Dysregulation of airway nerves underlies the development and manifestations of airway diseases such as chronic cough, where sensitization of neural pathways leads to excessive cough triggering. Nerves are heterogeneous in both expression and function. Recent advances in confocal imaging and in targeted genetic manipulation of airway nerves have expanded our ability to visualize neural organization, study neuro-immune interactions, and selectively modulate nerve activation. As a result, we have an unprecedented ability to quantitatively assess neural remodeling and its role in the development of airway disease. This review highlights our existing understanding of neural heterogeneity and how advances in methodology have illuminated airway nerve morphology and function in health and disease.

The Repurposing of Non-Peptide Neurokinin-1 Receptor Antagonists as Antitumor Drugs: An Urgent Challenge for Aprepitant

The substance P (SP)/neurokinin-1 receptor (NK-1R) system is involved in cancer progression. NK-1R, activated by SP, promotes tumor cell proliferation and migration, angiogenesis, the Warburg effect, and the prevention of apoptosis. Tumor cells overexpress NK-1R, which influences their viability. A typical specific anticancer strategy using NK-1R antagonists, irrespective of the tumor type, is possible because these antagonists block all the effects mentioned above mediated by SP on cancer cells. This review will update the information regarding using NK-1R antagonists, particularly Aprepitant, as an anticancer drug. Aprepitant shows a broad-spectrum anticancer effect against many tumor types. Aprepitant alone or in combination therapy with radiotherapy or chemotherapy could reduce the sequelae and increase the cure rate and quality of life of patients with cancer. Current data open the door to new cancer research aimed at antitumor therapeutic strategies using Aprepitant. To achieve this goal, reprofiling the antiemetic Aprepitant as an anticancer drug is urgently needed.

The Role of Substance P Receptor Antagonists in Allergic Rhinitis: Ovalbumin-Induced Rat Model

OBJECTIVE

Substance P is a peptide from the tachykinin family, which is found in peripheral and central nervous systems, causing vasodilation and increased secretion in the nasal mucosa. In this study, we aimed to investigate whether the experimental model of allergic rhinitis will cause allergic changes in the larynx and to compare the effects of aprepitant, a substance P antagonist, on nasal symptoms in allergic rhinitis, and histopathological changes in the nasal and laryngeal mucosa with antihistamine and leukotriene receptor antagonists (LTRA).

STUDY DESIGN

An experimental animal study.

METHOD

The study was carried out on 34 healthy 8-12 weeks old female Sprague Dawley rats in 5 groups. The rats in which an experimental allergic rhinitis model was created with ovalbumin were scored by observing their nasal symptoms, and nasal and laryngeal mucous membranes included in the study were evaluated histopathologically after medications.

RESULTS

As a result of the analysis of the data obtained from the study, antihistamine and LTRA significantly reduced the symptoms of nose scratching and sneezing, while aprepitant did not affect nasal symptoms. In the histopathological examination of the larynx, effects that would make a significant difference were found in the allergy group when compared to the control group. On the larynx, aprepitant reduced pseudostratification significantly compared to the allergy group.

CONCLUSION

Aprepitant provides histopathological changes in the treatment of allergic rhinitis, but does not have sufficient effect on nasal symptoms. The effect of aprepitant on the larynx has not been clearly demonstrated.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:2891-2897, 2023.

From bench to bedside: The role of cough hypersensitivity in chronic cough

BACKGROUND

Chronic cough is a burdensome condition characterized by persistent cough lasting longer than 8 weeks. Chronic cough can significantly affect quality of life, physical function and productivity, with many people troubled with a cough that lasts for months or even years. People with chronic cough commonly report a persistent urge to cough with frequent bouts of coughing triggered by innocuous stimuli, which has led to the concept of cough hypersensitivity.

MAIN BODY

Both central and peripheral neural pathways regulate cough, and although mechanisms driving development of cough hypersensitivity are not fully known, sensitization of these neural pathways contributes to excessive cough triggering in cough hypersensitivity. Effective therapies that control chronic cough are currently lacking. Recent therapeutic development has focused on several ion channels and receptors involved in peripheral activation of cough (e.g., transient receptor potential channels, P2 × 3 receptors and voltage-gated sodium channels) or central cough processing (e.g., neurokinin-1 [NK-1] receptors and nicotinic acetylcholine receptors).

CONCLUSION

These targeted therapies provide novel insights into mechanisms underlying cough hypersensitivity and may offer new treatment options for people with chronic cough. In this review, we explore preclinical and clinical studies that have improved our understanding of the mechanisms responsible for chronic cough and discuss the most promising targeted approaches to date, including trials of P2 × 3-receptor antagonists and NK-1-receptor antagonists.

Efficacy of gefapixant, a P2X3 antagonist, for lung cancer-related cough: a case report

Cough is a frequent symptom accompanied by lung cancer. More potent antitussive treatment for this complex and distressing symptom is required, but anti-cancer chemotherapy cannot fully manage the cough. Inhibition of vagal nerves might control coughing in patients with troublesome lung cancer-related cough and P2X3 inhibitory therapy may be useful for targeting neuronal function. We report the case of a woman in her late 70s who never smoked and had advanced lung cancer. She visited our hospital complaining of serious deterioration of a non-productive cough. She was diagnosed with relapse of lung cancer, but she requested 2-week anti-tussive therapy before second-line chemotherapy. Gefapixant (P2X3 antagonist) add-on at a dose of 90 mg/day (45 mg twice daily as the usual dosage in Japan) improved her cough as indicated by an improvement in the visual analog scale for cough from 70 to 20 mm and in the Japanese version of the Leicester Cough Questionnaire from 8.2 to 16.3, despite a deterioration in lung cancer after 2 weeks. There are no current guidelines for cough accompanied by lung cancer; however, our findings suggest that P2X3 inhibition is a potent therapeutic option for lung cancer-related cough.

Emerging drugs in the treatment of chronic cough

INTRODUCTION

Chronic cough is a debilitating condition that is among the most common reasons for seeking medical attention yet remains challenging to manage. Identifying an underlying respiratory, nasal or upper gastrointestinal disease triggering cough is the first step in assessment, but once this has been ruled out or adequately treated, many patients remain troubled with chronic cough.

AREAS COVERED

This narrative review discusses the role of existing treatments and describes the current research landscape for the development of new therapies for chronic cough greater than 8 weeks that is refractory (RCC) or unexplained (UCC). The literature search includes published studies found on pubmed and conference abstracts until 2023.

EXPERT OPINION

RCC/UCC can occur due to neuronal dysregulation of the vagus nerve or central nervous system. Hence, novel anti-tussives have targeted ion channels involved in the neuronal signaling which triggers cough. Although some therapies targeting receptors such as TRPV1 have failed to show efficacy, P2X3 antagonists have emerged as the most promising therapy for patients impacted by chronic cough. Disease specific therapies such as for idiopathic pulmonary fibrosis are in early development.

A case report of an 18-year-old receiving nebulized lidocaine for treatment of COVID-19 cough

An 18-year-old girl presenting with respiratory and gastrointestinal symptoms was found to have COVID-19 pneumonia and severe acute respiratory distress syndrome (ARDS). She was transferred to our pediatric intensive care unit (PICU) for ongoing mechanical ventilation and initiation of venovenous extracorporeal membrane oxygenation (VV-ECMO) for management of progressive hypoxic respiratory failure. She developed a worsening cough with associated life-threatening desaturation events that impaired ECMO flow and required deep sedation. Despite multiple sedative agents, our patient continued to have frequent coughing episodes with associated tachycardia, hypertension, and hypoxemia. The PICU team started nebulized lidocaine 1% 4 mL (40 mg) every 6 hours with albuterol pretreatment, gabapentin, and scheduled ipratropium. Lidocaine levels were <1 mcg/mL throughout the treatment duration. Nebulized lidocaine was stopped after 18 days given improvement in coughing episode severity. Our patient is one of the first reports of an adolescent patient receiving nebulized lidocaine for COVID-19 associated cough. Administration of nebulized lidocaine was well tolerated in this patient without adverse effects and was associated with decreased sedation needs. Given the widespread impact of the COVID-19 pandemic and its sequelae in pediatric, adolescent, and adult patients, additional research is warranted to explore options for management of COVID-19 associated cough.

Cardioprotective action of aprepitant in a rat model of ischemia-reperfusioninduced myocardial injury: role of PI3K-AkT-GSK-3β-HIF-1α signaling pathway

PURPOSE

The present study explored the role and mechanism involved in aprepitant-induced cardioprotective effects in rat model of ischemia-reperfusion injury.

METHODS

The isolated hearts of Wistar male albino rats were subjected to ischemia-reperfusion injury on Langendorff apparatus. The extent of myocardial injury was assessed by measuring lactate dehydrogenase 1 and CK-MB release in the coronary effluent. The rats were treated with aprepitant (5, 10 and 20 mg/kg) before isolating hearts. After injury, the levels of HIF-1α, p-AkT, p-GSK-3β/GSK-3β were measured in heart homogenates. LY294002 was employed as PI3K inhibitor.

RESULTS

Ischemia-reperfusion led to significant myocardial injury and decreased the levels of HIF-1α, p-AkT and ratio of p-GSK-3β/GSK-3β. Aprepitant attenuated myocardial injury and restored the biochemical changes in a dose-dependent manner. Pre-treatment with LY294002 (10 and 20 mg/kg) abolished aprepitant-mediated cardioprotective effects and restored the biochemical parameters in the heart homogenate.

CONCLUSIONS

Aprepitant may be effective in preventing ischemia-reperfusion-induced myocardial injury, which may be due to activation of PI3K-AkT-GSK-3β and HIF-1α signaling pathway.

The burden and impact of chronic cough in severe disease

PURPOSE OF REVIEW

Chronic cough is common in severe diseases, such as COPD, interstitial lung disease, lung cancer and heart failure, and has a negative effect on quality of life. In spite of this, patients with cough sometimes feel their cough is neglected by healthcare workers. This review aims to briefly describe cough mechanisms, highlight the burden chronic cough can be for the individual, and the clinical impact of chronic cough.

RECENT FINDINGS

Chronic cough is likely caused by different mechanisms in different diseases, which may have therapeutic implications. Chronic cough, in general, has a significant negative effect on quality of life, both with and without a severe comorbid disease. It can lead to social isolation, recurrent depressive episodes, lower work ability, and even conditions such as urinary incontinence. Cough may also be predictive of more frequent exacerbations among patients with COPD, and more rapid lung function decline in idiopathic pulmonary fibrosis. Cough is sometimes reported by patients to be underappreciated by healthcare.

SUMMARY

Chronic cough has a significant negative impact on quality of life, irrespective of diagnosis. Some differences are seen between patients with and without severe disease. Healthcare workers need to pay specific attention to cough, especially patients with severe disease.

Cough hypersensitivity and chronic cough

Chronic cough is globally prevalent across all age groups. This disorder is challenging to treat because many pulmonary and extrapulmonary conditions can present with chronic cough, and cough can also be present without any identifiable underlying cause or be refractory to therapies that improve associated conditions. Most patients with chronic cough have cough hypersensitivity, which is characterized by increased neural responsivity to a range of stimuli that affect the airways and lungs, and other tissues innervated by common nerve supplies. Cough hypersensitivity presents as excessive coughing often in response to relatively innocuous stimuli, causing significant psychophysical morbidity and affecting patients' quality of life. Understanding of the mechanisms that contribute to cough hypersensitivity and excessive coughing in different patient populations and across the lifespan is advancing and has contributed to the development of new therapies for chronic cough in adults. Owing to differences in the pathology, the organs involved and individual patient factors, treatment of chronic cough is progressing towards a personalized approach, and, in the future, novel ways to endotype patients with cough may prove valuable in management.

Identifying patients who suffered from post-discharge cough after lung cancer surgery

PURPOSE

To establish a discharge cutoff point (CP) on a simple patient-reported cough score to identify patients requiring post-discharge cough intervention.

METHODS

Data were extracted from a prospective cohort study of patients undergoing lung cancer surgery. Symptoms were assessed using the MD Anderson Symptom Inventory-Lung Cancer Module. Group-based trajectory modeling was used to identify patient subgroups defined by post-discharge cough trajectories. Generalized linear model and bootstrap resampling with 2000 samples were used to determine the optimal cutoff points of discharge cough scores and their robustness. Analysis of variance, chi-square test, and mixed-effects model were used to validate the optimal cutoff points.

RESULTS

The cough trajectories of post-discharge followed three patterns (high, middle, low); higher cough was associated with poor recovery of the enjoyment of life within 4 weeks after discharge (P < 0.001). The CP (3, 6) of discharge cough demonstrated as the optimal CP (F = 21.72). When discharged, 45.66% (179/392) of patients suffered a none/mild cough (0-2 points), 41.82% (164/392) suffered a moderate cough (3-5 points), and 12.5% (49/392) suffered a severe cough (6-10 points). Among these patients, there was a significant difference in the proportion of returning to work at 1 month after discharge (non-mild: 77.70%; moderate: 60.74%; severe: 48.57%; p < 0.001).

CONCLUSIONS

Moderate-to-severe cough is relatively common in patients undergoing lung cancer surgery, and the higher the cough trajectory, the worse the recovery to normal life. Therefore, these patients with a cough score ≥ 3 or ≥ 6 at discharge may require additional medical intervention and extensive care.

Knockdown of lncRNA PCAT6 suppresses the growth of non-small cell lung cancer cells by inhibiting macrophages M2 polarization via miR-326/KLF1 axis

Non-small cell lung cancer (NSCLC) is the most common malignant tumor of lung, which seriously threatens the life of people. It has been reported that lncRNA prostate cancer-associated transcript 6 (PCAT6) could facilitate the metastasis of NSCLC cells. However, whether lncRNA PCAT6 in NSCLC cells could affect the tumor microenvironment (TME) remains unclear. In the present study, the level of PCAT6 in NSCLC cells was detected using RT-qPCR. The effects of PCAT6 knockdown on the viability and apoptosis in NSCLC cells were detected with CCK-8 and flow cytometry assay. NSCLC cell-derived exosomes were isolated with ultracentrifugation. Next, transwell assay was conducted to assess the migration and invasion of NSCLC cells. Dual-luciferase reporter assay was performed to verify the relationship among PCAT6, miR-326, and KLF1 in A549 cells. In addition, nanoparticle tracking analysis (NTA) was applied to detect the particle size of isolated exosomes. Moreover, ELISA assay was performed to detect the levels of IL-1β and IL-10 in the supernatant of macrophage. We found knockdown of PCAT6 significantly inhibited the viability, migration, and invasion of NSCLC cells. In addition, dual-luciferase reporter assay illustrated that miR-326 was the target of PCAT6 and KLF1 was the target of miR-326 in NSCLC cells. Moreover, NSCLC cells-derived exosomes could promote macrophages M2 polarization by transporting PCAT6. Meanwhile, macrophages M2 polarization was able to promote the metastasis and epithelial-mesenchymal transition (EMT) process of NSCLC cells via regulating PCAT6/miR-326/KLF1 axis. Taken together, knockdown of lncRNA PCAT6 suppressed the growth of NSCLC cells by inhibiting macrophages M2 polarization via miR-326/KLF1 axis.