Biologics (mepolizumab and omalizumab) induced remission in severe asthma patients.

BACKGROUND: Asthma remission has emerged as a potential treatment goal. This study evaluated the effectiveness of two biologics (mepolizumab/omalizumab) in achieving asthma remission. METHODS: This observational study included 453 severe asthma patients (41% male; mean age ± SD 55.7 ± 14.7 years) from two real-world drug registries: the Australian Mepolizumab Registry and the Australian Xolair Registry. The composite outcome clinical remission was defined as zero exacerbations and zero oral corticosteroids during the previous 6 months assessed at 12 months and 5-item Asthma Control Questionnaire (ACQ-5) ≤1 at 12 months. We also assessed clinical remission plus optimization (post-bronchodilator FEV1 ≥80%) or stabilization (post-bronchodilator FEV1 not greater than 5% decline from baseline) of lung function at 12 months. Sensitivity analyses explored various cut-offs of ACQ-5/FEV1 scores. The predictors of clinical remission were identified. RESULTS: 29.3% (73/249) of AMR and 22.8% (37/162) of AXR cohort met the criteria for clinical remission. When lung function criteria were added, the remission rates were reduced to 25.2% and 19.1%, respectively. Sensitivity analyses identified that the remission rate ranged between 18.1% and 34.9% in the AMR cohort and 10.6% and 27.2% in the AXR cohort. Better lung function, lower body mass index, mild disease and absence of comorbidities such as obesity, depression and osteoporosis predicted the odds of achieving clinical remission. CONCLUSION: Biologic treatment with mepolizumab or omalizumab for severe asthma-induced asthma remission in a subgroup of patients. Remission on treatment may be an achievable treatment target and future studies should consider remission as an outcome measure.

Impact of Landscape Fire Smoke Exposure on Patients With Asthma With or Without Laryngeal Hypersensitivity.

BACKGROUND: Individuals with asthma experienced severe and prolonged symptoms after the Australian 2019 to 2020 landscape fire. Many of these symptoms, such as throat irritation, occur in the upper airway. This suggests that laryngeal hypersensitivity contributes to persistent symptoms after smoke exposure. OBJECTIVE: This study examined the relationship between laryngeal hypersensitivity and symptoms, asthma control, and health impacts on individuals exposed to landscape fire smoke. METHOD: The study was a cross-sectional survey of 240 participants in asthma registries who were exposed to smoke during the 2019 to 2020 Australian fire. The survey, completed between March and May 2020, included questions about symptoms, asthma control, and health care use, as well as the Laryngeal Hypersensitivity Questionnaire. Daily concentration levels of particulate matter less than or equal to 2.5 µm in diameter were measured over the 152-day study period. RESULTS: The 49 participants with laryngeal hypersensitivity (20%) had significantly more asthma symptoms (96% vs 79%; P = .003), cough (78% vs 22%; P < .001), and throat irritation (71% vs 38%; P < .001) during the fire period compared with those without laryngeal hypersensitivity. Participants with laryngeal hypersensitivity had greater health care use (P ≤ .02), more time off work (P = .004), and a reduced capacity to participate in usual activities (P < .001) during the fire period, as well as poorer asthma control during the follow-up (P = .001). CONCLUSIONS: Laryngeal hypersensitivity is associated with persistent symptoms, reports of lower asthma control, and increased health care use in adults with asthma who were exposed to landscape fire smoke. Management of laryngeal hypersensitivity before, during, or immediately after landscape fire smoke exposure might reduce the symptom burden and health impact.

'Breathing Fire': Impact of Prolonged Bushfire Smoke Exposure in People with Severe Asthma.

Wildfires are increasing and cause health effects. The immediate and ongoing health impacts of prolonged wildfire smoke exposure in severe asthma are unknown. This longitudinal study examined the experiences and health impacts of prolonged wildfire (bushfire) smoke exposure in adults with severe asthma during the 2019/2020 Australian bushfire period. Participants from Eastern/Southern Australia who had previously enrolled in an asthma registry completed a questionnaire survey regarding symptoms, asthma attacks, quality of life and smoke exposure mitigation during the bushfires and in the months following exposure. Daily individualized exposure to bushfire particulate matter (PM2.5) was estimated by geolocation and validated modelling. Respondents (n = 240) had a median age of 63 years, 60% were female and 92% had severe asthma. They experienced prolonged intense PM2.5 exposure (mean PM2.5 32.5 µg/m3 on 55 bushfire days). Most (83%) of the participants experienced symptoms during the bushfire period, including: breathlessness (57%); wheeze/whistling chest (53%); and cough (50%). A total of 44% required oral corticosteroid treatment for an asthma attack and 65% reported reduced capacity to participate in usual activities. About half of the participants received information/advice regarding asthma management (45%) and smoke exposure minimization strategies (52%). Most of the participants stayed indoors (88%) and kept the windows/doors shut when inside (93%), but this did not clearly mitigate the symptoms. Following the bushfire period, 65% of the participants reported persistent asthma symptoms. Monoclonal antibody use for asthma was associated with a reduced risk of persistent symptoms. Intense and prolonged PM2.5 exposure during the 2019/2020 bushfires was associated with acute and persistent symptoms among people with severe asthma. There are opportunities to improve the exposure mitigation strategies and communicate these to people with severe asthma.

Cavitating Lung Disease Associated With Sudden Death.

CASE PRESENTATION: A 16-year-old boy presented with 6 days of left iliac fossa pain. He had a medical history of right subtalar dislocation and appendicitis requiring laparotomy 3 years earlier, complicated by wound dehiscence. His family history was significant for his brother's sudden death 3 weeks prior after a 12-month illness with intermittent epigastric pain, weight loss, and hemoptysis. Travel history was significant for travel to the Philippines 3 years prior, in which he spent time in the hospital for appendicitis.

Mepolizumab and Oral Corticosteroid Stewardship: Data from the Australian Mepolizumab Registry.

BACKGROUND: Oral corticosteroids (OCS) carry serious health risks. Innovative treatment options are required to reduce excessive exposure and promote OCS stewardship. OBJECTIVES: This study evaluated the trajectories of OCS exposure (prednisolone-equivalent) in patients with severe eosinophilic asthma before and after starting mepolizumab and the predictors of becoming OCS free after 6 months of mepolizumab therapy. METHODS: This real-world observational study included 309 patients from the Australian Mepolizumab Registry who were followed up for 1 year (n = 225). RESULTS: Patients had a median age of 60 (interquartile range: 50, 68) years, and 58% were female. At baseline, 48% used maintenance OCS, 96% had ≥1 OCS burst, and 68% had received ≥1 g of OCS in the previous year. After commencing mepolizumab, only 55% of those initially on maintenance OCS remained on this treatment by 12 months. Maintenance OCS dose reduced from median 10 (5.0, 12.5) mg/day at baseline to 2 (0, 7.0) mg/day at 12 months (P < .001). Likewise, proportions of patients receiving OCS bursts in the previous year reduced from 96% at baseline to 50% at 12 months (P < .001). Overall, 137 (48%) patients required OCS (maintenance/burst) after 6 months' mepolizumab therapy. Becoming OCS free was predicted by a lower body mass index (odds ratio: 0.925; 95% confidence interval: 0.872-0.981), late-onset asthma (1.027; 1.006-1.048), a lower Asthma Control Test score (1.111; 0.011-1.220), and not receiving maintenance OCS therapy at baseline (0.095; 0.040-0.227). CONCLUSION: Mepolizumab led to a significant and sustained reduction in OCS dependence in patients with severe eosinophilic asthma. This study supports the OCS-sparing effect of mepolizumab and highlights the pivotal role of mepolizumab in OCS stewardship initiatives.

Survival and late toxicities following concurrent chemo-radiotherapy for locally advanced stage III non-small cell lung cancer: findings of a 10-year Australian single centre experience with long term clinical follow up.

BACKGROUND: The preferred management of patients with unresectable locally advanced non-small cell lung cancer (LA-NSCLC) is concurrent chemo-radiotherapy (CRT). Acute CRT-related toxicities are well defined, however, less is known about late toxicities. The aim of the study was to examine the outcomes and late toxicities in Stage III NSCLC treated with CRT. METHODS: A retrospective review of the data from patients with stage III NSCLC treated with CRT was performed between May 2000 and June 2010. Demographics, tumour and treatment characteristics, toxicities and survival data were examined from hospital records of the patients. Progression free survival (PFS) and overall survival (OS) were evaluated by standard Kaplan-Meier survival curves. The censor date was set on 31 October 2016. RESULTS: Sixty-three patients were identified with a median age of 66.6 years [interquartile range (IQR) 57.2-72.1], two-third (n=41, 65.1%) were male, majority were current or ex-smokers (n=52, 82.5%), 42 (66.7%) patients had stage IIIB disease and 21 (33.3%) had stage IIIA disease. The most common histologic subtype was adenocarcinoma 30 (47.6%). The median PFS and OS of the whole population was 10.6 months (95% CI, 4.1-17.3 months) and 21 months (95% CI, 12.7-29.3 months) respectively. The 5-year OS rates for stage IIIA and IIIB were 24% and 16% respectively. The 1-, 3- and 5-year OS rates for all patients were 63.5%, 46% and 18.7% respectively. Acute grade 3 and 4 toxicities included 28 haematological and 17 non-haematological events. The incidence of late toxicities was 58.9%. Thirty-three events of late grade 3 and 4 toxicities were recorded. The most common late toxicity was symptomatic radiation-induced pulmonary fibrosis (39.3%), others include ototoxicity (7.1%), persistent dysphagia (7.1%) and one case of acute myeloid leukaemia. All patients that were alive at the censor date had developed radiation-induced fibrosis with associated symptoms of respiratory insufficiency. CONCLUSIONS: The 5-year OS of patients with stage III NSCLC treated with CRT was in keeping with survival figures reported from prospective clinical trials. There is, however, significant morbidity associated with long-term survival and this should be taken into account when making informed treatment decisions.

Australian recommendations for EGFR T790M testing in advanced non-small cell lung cancer.

First-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are used as first-line therapy in patients with non-small cell lung cancer (NSCLC) harboring a sensitizing mutation in the EGFR gene. Unfortunately, resistance to these therapies often occurs within 10 months of commencing treatment and is mostly commonly due to the development of the EGFR T790M mutation. Treatment with the third-generation EGFR TKI, osimertinib can prolong progression free survival in patients with the T790M mutation, so it is important to determine the resistance mechanism in order to plan ongoing therapeutic strategies. Here we review the evidence and make recommendations for the timing of T790M mutation testing, the most appropriate specimens to test and the available testing methods in patients progressing during treatment with first line EGFR TKIs for NSCLC.

Warfarin resistance associated with genetic polymorphism of VKORC1: linking clinical response to molecular mechanism using computational modeling.

The variable response to warfarin treatment often has a genetic basis. A protein homology model of human vitamin K epoxide reductase, subunit 1 (VKORC1), was generated to elucidate the mechanism of warfarin resistance observed in a patient with the Val66Met mutation. The VKORC1 homology model comprises four transmembrane (TM) helical domains and a half helical lid domain. Cys132 and Cys135, located in the N-terminal end of TM-4, are linked through a disulfide bond. Two distinct binding sites for warfarin were identified. Site-1, which binds vitamin K epoxide (KO) in a catalytically favorable orientation, shows higher affinity for S-warfarin compared with R-warfarin. Site-2, positioned in the domain occupied by the hydrophobic tail of KO, binds both warfarin enantiomers with similar affinity. Displacement of Arg37 occurs in the Val66Met mutant, blocking access of warfarin (but not KO) to Site-1, consistent with clinical observation of warfarin resistance.

Bolus intravenous 0.9% saline, but not 4% albumin or 5% glucose, causes interstitial pulmonary edema in healthy subjects.

Rapid intravenous (iv) infusion of 0.9% saline alters respiratory mechanics in healthy subjects. However, the relative cardiovascular and respiratory effects of bolus iv crystalloid vs. colloid are unknown. Six healthy male volunteers were given 30 ml/kg iv 0.9% saline, 4% albumin, and 5% glucose at a rate of 100 ml/min on 3 separate days in a double-blinded, randomized crossover study. Impulse oscillometry, spirometry, lung volumes, diffusing capacity (DLCO), and blood samples were measured before and after fluid administration. Lung ultrasound B-line score (indicating interstitial pulmonary edema) and Doppler echocardiography indices of cardiac preload were measured before, midway, immediately after, and 1 h after fluid administration. Infusion of 0.9% saline increased small airway resistance at 5 Hz (P = 0.04) and lung ultrasound B-line score (P = 0.01) without changes in Doppler echocardiography measures of preload. In contrast, 4% albumin increased DLCO, decreased lung volumes, and increased the Doppler echocardiography mitral E velocity (P = 0.001) and E-to-lateral/septal e' ratio, estimated blood volume, and N-terminal pro B-type natriuretic peptide (P = 0.01) but not lung ultrasound B-line score, consistent with increased pulmonary blood volume without interstitial pulmonary edema. There were no significant changes with 5% glucose. Plasma angiopoietin-2 concentration increased only after 0.9% saline (P = 0.001), suggesting an inflammatory mechanism associated with edema formation. In healthy subjects, 0.9% saline and 4% albumin have differential pulmonary effects not attributable to passive fluid filtration. This may reflect either different effects of these fluids on active signaling in the pulmonary circulation or a protective effect of albumin.