As-needed low-dose inhaled corticosteroid/formoterol therapy in patients with severe asthma included in the German Asthma Net cohort.

After the GINA update in 2019, the proportion of SMART therapy increased with evidence for better disease control in SMART patients compared to SABA alone https://bit.ly/3SSPX1C.

Real-World Characteristics of Patients with Severe Asthma prior to Starting Dupilumab: The ProVENT Study.

INTRODUCTION: Dupilumab is approved for the treatment of severe type 2 (T2) asthma; however, the characteristics of patients receiving dupilumab in routine clinical practice are incompletely understood. This study describes the characteristics of patients with severe asthma before dupilumab treatment in a real-world setting. METHODS: This interim analysis of an ongoing real-life study of dupilumab assessed baseline characteristics of the first patient cohort enrolled in the ProVENT study. RESULTS: A total of 99 patients (59% females) were analyzed (17% received another biologic before dupilumab treatment and 15% were on maintenance oral corticosteroid treatment). Adult-onset asthma (>18 years) and an allergic phenotype were documented in 58% and 48% of patients, respectively. Median (interquartile range) age was 54 (40-61) years; the median number of exacerbations in the last 24 months was 1 (0-3); median fractional exhaled nitric oxide (FeNO) value was 38 (23-64) ppb; and median blood eosinophils (bEOS) count was 184 (8-505) cells/µL. According to the United Kingdom Severe Asthma Registry classification, 53% of patients had T2 intermediate asthma (bEOS ≥150 cells/µL or FeNO ≥25 ppb), 17% had T2 high asthma (bEOS ≥150 cells/µL and FeNO ≥25 ppb), and 4% had T2 low asthma (bEOS <150 cells/µL and FeNO <25 ppb). At least one GINA criterion for T2 airway inflammation was documented in 70% of patients. T2 comorbidities were observed in 64% of patients. CONCLUSIONS: This analysis suggests that patients eligible for dupilumab treatment display various clinical and biochemical characteristics rather than one clear-cut phenotype.

Reduction of daily maintenance inhaled corticosteroids in patients with severe eosinophilic asthma treated with benralizumab (SHAMAL): a randomised, multicentre, open-label, phase 4 study.

BACKGROUND: Stepwise intensification of inhaled corticosteroids (ICS) is routine for severe eosinophilic asthma, despite some poor responses to high-dose ICS. Dose reductions are recommended in patients responding to biologics, but little supporting safety evidence exists. METHODS: SHAMAL was a phase 4, randomised, open-label, active-controlled study done at 22 study sites in four countries. Eligible participants were adults (aged ≥18 years) with severe eosinophilic asthma and a five-item Asthma Control Questionnaire score below 1·5 and who received at least three consecutive doses of benralizumab before screening. We randomly assigned patients (3:1) to taper their high-dose ICS to a medium-dose, low-dose, and as-needed dose (reduction group) or continue (reference group) their ICS-formoterol therapy for 32 weeks, followed by a 16-week maintenance period. The primary endpoint was the proportion of patients reducing their ICS-formoterol dose by week 32. The primary outcome was assessed in the reduction group, and safety analyses included all randomly assigned patients receiving study treatment. This study is registered at ClinicalTrials.gov, NCT04159519. FINDINGS: Between Nov 12, 2019, and Feb 16, 2023, we screened and enrolled in the run-in period 208 patients. We randomly assigned 168 (81%) to the reduction (n=125 [74%]) and reference arms (n=43 [26%]). Overall, 110 (92%) patients reduced their ICS-formoterol dose: 18 (15%) to medium-dose, 20 (17%) to low-dose, and 72 (61%) to as-needed only. In 113 (96%) patients, reductions were maintained to week 48; 114 (91%) of patients in the reduction group had zero exacerbations during tapering. Rates of adverse events were similar between groups. 91 (73%) patients had adverse events in the reduction group and 35 (83%) in the reference group. 17 patients had serious adverse events in the study: 12 (10%) in the reduction group and five (12%) in the reference group. No deaths occurred during the study. INTERPRETATION: These findings show that patients controlled on benralizumab can have meaningful reductions in ICS therapy while maintaining asthma control. FUNDING: AstraZeneca.

Tezepelumab in patients with allergic and eosinophilic asthma.

Asthma is a heterogeneous disease commonly driven by allergic and/or eosinophilic inflammation, both of which may be present in severe disease. Most approved biologics for severe asthma are indicated for specific phenotypes and target individual downstream type 2 components of the inflammatory cascade. Tezepelumab, a human monoclonal antibody (immunoglobulin G2λ), binds specifically to thymic stromal lymphopoietin (TSLP), an epithelial cytokine that initiates and sustains allergic and eosinophilic inflammation in asthma. By blocking TSLP, tezepelumab has demonstrated efficacy across known asthma phenotypes and acts upstream of all current clinically used biomarkers. In a pooled analysis of the phase 2b PATHWAY (NCT02054130) and phase 3 NAVIGATOR (NCT03347279) studies, compared with placebo, tezepelumab reduced the annualized asthma exacerbation rate over 52 weeks by 62% (95% confidence interval [CI]: 53, 70) in patients with perennial aeroallergen sensitization (allergic asthma); by 71% (95% CI: 62, 78) in patients with a baseline blood eosinophil count ≥300 cells/µL; and by 71% (95% CI: 59, 79) in patients with allergic asthma and a baseline blood eosinophil count ≥300 cells/µL. This review examines the efficacy and mode of action of tezepelumab in patients with allergic asthma, eosinophilic asthma and coexisting allergic and eosinophilic phenotypes.

Initiation, response assessment, and switch of antibody therapies in patients with severe asthma - A survey among German specialists.

Background: For therapy of severe asthma 5 monoclonal antibodies have been available in Germany up to November 2022, but no clear rules exist on choice of initial therapy, assessment of response, and switch. Objective: To assess current practice on all aspects of biologic therapy by specialists in Germany. Methods: A questionnaire was created by specialists for severe asthma, which was tested and modified by further experts. We invited 119 pulmonologists of the German Asthma Net (GAN) to complete the survey and used SoSci Survey and SPSS for data collection and analysis. Results: Forty-seven pulmonologists took part in the survey with a median annual number of patients treated with biologics of 35, 55% worked in an outpatient practice, and 40% in a hospital. Exacerbations and oral steroid use were the most important factors for the decision to start a biologic therapy. Accordingly, these parameters were also the most relevant for assessment of response. Most participants considered type-2 inflammation biomarkers and comorbidities (foremost CRSwNP and AD) for choosing initial biologic. Asthma Control Test (ACT) was the most common instrument for assessing status of disease control. There was no consensus on thresholds for response of pulmonary function tests including FEV1, FVC, and RV. Eighty-five percent of participants distinguished between "responders", "partial responders" and "non-responders". Comorbidities played an important role for the decision to switch to another biologic, eg, when initial therapy had insufficient effectiveness on CRSwNP. Conclusion: This study provides a detailed insight into current opinions and practice of biologic use in severe asthma in Germany.

Characterization of Austrian severe asthma patients.

INTRODUCTION: The Severe Asthma Registry, founded by German Asthma Net (GAN) in 2011, is a prospective registry recording clinical parameters from participating centers in Germany, Austria and Switzerland. This article presents the baseline characteristics of severe asthma patients from Austrian centers. METHODS: We analyzed the baseline visit data of all patients recruited to the GAN Severe Asthma Registry from participating Austrian centers. RESULTS: Baseline visit data were available for 214 Austrian severe asthma patients from 6 Austrian centers from 2013 to 2022. Mean age was 53.7 years. Mean BMI was 26.4 kg/m2. More than a third (37.4%) of all patients had daily daytime asthma symptoms at baseline and had to use their reliever medication at least once per day. Forty-one percent of patients were classified as uncontrolled according to GINA and 24.8% as partially controlled at baseline visit. The median annual exacerbation frequency was 3 in the previous 12 months. At the time of baseline visit, 23.4% of all patients had regular treatment with oral corticosteroids. Furthermore, 23.9% had received any severe asthma monoclonal antibody prior to the baseline visit. There were no notable differences in baseline characteristics between patients categorized by smoking history or measurable type 2 inflammation. CONCLUSIONS: This study provides the first multi-center characterization of Austrian severe asthma patients. Patients in this cohort had better asthma control and less frequent exacerbations compared to most international registries.

Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS).

BACKGROUND: The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined. AIM: To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy. METHODS: 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma. RESULT: We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", "reduction 50-74 %", "reductio < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control ("ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered. CONCLUSION: The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.] / S2k-Leitlinie zur fachärztlichen Diagnostik und Therapie von Asthma 2023.

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Characterization of Obesity in Severe Asthma in the German Asthma Net.

BACKGROUND: Asthma is increasingly recognized as heterogeneous, characterized by different endotypes, with obesity not only a distinct phenotype but a risk factor for severe asthma. OBJECTIVE: We sought to understand the associations of obesity with relevant parameters of severe asthma, including asthma control, disease burden, and lung function. METHODS: The German Asthma Net registry is a multicenter international real-life registry capturing long-term follow-up data. This analysis included 2213 patients (52 ± 16 years, 58% female, 29% with obesity [body mass index ≥30 kg/m2], 4.2 ± 4.3 exacerbations/year). The primary analysis assessed relationships between BMI and variables through univariate tests, followed by a multiple regression model. Secondary outcomes regarded clinically relevant variables in relation to weight groups. RESULTS: Patients with obesity were more frequently female, more likely to have depression and gastroesophageal reflux, and suffered from worse asthma control, lower quality of life, reduced static lung volumes, more pronounced hypoxemia, and higher blood neutrophil counts, all statistically significant. Blood eosinophils, exhaled nitric oxide, and total IgE were independent of obesity. In the multiple regression analysis, obesity was significantly associated with more frequent reflux and depression, reduced static lung function values, older age, poor asthma control, and long-acting muscarinic antagonist therapy, and inversely associated with bronchiectasis and nonsmoking status. CONCLUSION: In this large, well-characterized cohort, we identified the association of obesity with a significantly higher disease burden and a similar portfolio of inflammation type 2 markers in patients with and without obesity; therefore, patients with obesity seem similarly eligible for the treatment with biologics targeting these disease endotypes.

Response to Biologics and Clinical Remission in the Adult German Asthma Net Severe Asthma Registry Cohort.

BACKGROUND: Recently, criteria for evaluation of response to biologics have been proposed and the concept of clinical remission has gained attention as a possible goal even in severe asthma. OBJECTIVE: To analyze the response and remission in the German Asthma Net severe asthma registry cohort. METHODS: We included adults not using a biologic at baseline (V0) and compared patients treated between V0 and 1-year visit (V1) without using a biologic (group A) to patients starting with a biologic after V0 and continuing it up to V1 (group B). We applied the Biologics Asthma Response Score to quantify composite response in good, intermediate, or insufficient. We defined clinical remission (R) as absence of significant symptoms (Asthma Control Test score ≥ 20 at V1) in the absence of exacerbations and oral corticosteroid therapy. RESULTS: Group A included 233 and group B 210 patients, the latter receiving omalizumab (n = 33), mepolizumab (n = 40), benralizumab (n = 81), reslizumab (n = 1), or dupilumab (n = 56). At baseline, group B had less often an allergic phenotype (35.2% vs 41.6%), lower Asthma Control Test score (median, 12 vs 14), more exacerbations in the past year (median, 3 vs 2), and more often high-dose inhaled corticosteroid treatment (71.4% vs 51.5%) than group A. After 1 year of treatment, rates of response (good: 61.4% vs 34.8%; intermediate: 26.7% vs 42.9%; insufficient: 11.9% vs. 22.3%) and/or clinical remission (37.6% vs 17.2%) were higher in group B than in group A. CONCLUSIONS: Despite more severe asthma at baseline, patients treated with biologics had a markedly higher probability of achieving good clinical response and/or remission than patients treated without biologics.

Efficacy of Biologics in Severe, Uncontrolled Asthma Stratified by Blood Eosinophil Count: A Systematic Review.

INTRODUCTION: Randomized controlled trials (RCTs) of biologics in patients with severe, uncontrolled asthma have shown differential results by baseline blood eosinophil count (BEC). In the absence of head-to-head trials, we describe the effects of biologics on annualized asthma exacerbation rate (AAER) by baseline BEC in placebo-controlled RCTs. Exacerbations associated with hospitalization or an emergency room visit, pre-bronchodilator forced expiratory volume in 1 s, Asthma Control Questionnaire score, and Asthma Quality of Life Questionnaire score were also summarized. METHODS: MEDLINE (via PubMed) was searched for RCTs of biologics in patients with severe, uncontrolled asthma and with AAER reduction as a primary or secondary endpoint. AAER ratios and change from baseline in other outcomes versus placebo were compared across baseline BEC subgroups. Analysis was limited to US Food and Drug Administration-approved biologics. RESULTS: In patients with baseline BEC ≥ 300 cells/µL, AAER reduction was demonstrated with all biologics, and other outcomes were generally improved. In patients with BEC 0 to < 300 cells/µL, consistent AAER reduction was demonstrated only with tezepelumab; improvements in other outcomes were inconsistent across biologics. In patients with BEC 150 to < 300 cells/µL, consistent AAER reduction was demonstrated with tezepelumab and dupilumab (300 mg dose only), and in those with BEC 0 to < 150 cells/µL, AAER reduction was demonstrated only with tezepelumab. CONCLUSION: The efficacy of all biologics in reducing AAER in patients with severe asthma increases with higher baseline BEC, with varying profiles across individual biologics likely due to differing mechanisms of action.

Real-World Experience on the Use of Mepolizumab from the Severe Asthma Registry of the German Asthma Net (MepoGAN-Study).

Purpose: The German Asthma Net (GAN) operates a Severe Asthma Registry that provides an overview of the clinical presentation and management of patients with severe asthma. Based upon data from the GAN registry, the MepoGAN study aimed to describe clinical profiles and treatment outcomes of patients who were treated with the anti-IL-5 monoclonal antibody mepolizumab (NucalaTM) in routine practice in Germany. Patients and Methods: The MepoGAN study is a descriptive retrospective non-interventional cohort study. Mepolizumab patients enrolled in the GAN registry were evaluated with results being described in two different data sets: Cohort 1 (n=131) started on mepolizumab when the patients entered the registry. Results were reported after 4 months of therapy. Patients in Cohort 2 (n=220) were on treatment with mepolizumab at the time of enrollment and follow-up data were collected after a further year of treatment. Outcome measures included asthma control, lung function, disease symptoms, OCS use, and exacerbations. Results: Patients enrolled in the registry who started on mepolizumab in Cohort 1 had a mean age of 55 years, were former smokers in 51% of the cases, had a mean blood eosinophil count of 500 cells/µL, and frequently had maintenance OCS use (55%). In this real-world setting, mepolizumab therapy was associated with a clinically relevant reduction in blood eosinophils (-445.7 cells/µL), OCS use (-30%), and improvement in asthma control. Fifty-five percent (vs 10% at baseline) of the patients reported controlled or partially controlled asthma 4 months after starting therapy. In patients who were already treated with mepolizumab at registry enrollment (Cohort 2), asthma control and lung function remained stable after a further year of observation. Conclusion: The GAN registry data confirm the effectiveness of mepolizumab in a real-world setting. Treatment benefits are maintained over time. While the asthma of patients treated in routine practice was more severe, the results observed with mepolizumab are broadly consistent with RCTs.

Efficacy of Tezepelumab in Severe, Uncontrolled Asthma: Pooled Analysis of the PATHWAY and NAVIGATOR Clinical Trials.

Rationale: Tezepelumab reduced exacerbations in patients with severe, uncontrolled asthma across a range of baseline blood eosinophil counts and fractional exhaled nitric oxide levels, and irrespective of allergy status, in the phase 2b PATHWAY (Study to Evaluate the Efficacy and Safety of MEDI9929 [AMG 157] in Adult Subjects With Inadequately Controlled, Severe Asthma; NCT02054130) and phase 3 NAVIGATOR (Study to Evaluate Tezepelumab in Adults & Adolescents With Severe Uncontrolled Asthma; NCT03347279) trials. Objectives: To examine the efficacy and safety of tezepelumab in additional clinically relevant subgroups using pooled data from PATHWAY and NAVIGATOR. Methods: PATHWAY and NAVIGATOR were randomized, double-blind, placebo-controlled trials with similar designs. This pooled analysis included patients with severe, uncontrolled asthma (PATHWAY, 18-75 years old; NAVIGATOR, 12-80 years old) who received tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. The annualized asthma exacerbation rate over 52 weeks and secondary outcomes were calculated in the overall population and in subgroups defined by inflammatory biomarker levels or clinical characteristics. Measurements and Main Results: Overall, 1,334 patients were included (tezepelumab, n = 665; placebo, n = 669). Tezepelumab reduced the annualized asthma exacerbation rate versus placebo by 60% (rate ratio, 0.40 [95% confidence interval, 0.34-0.48]) in the overall population, and clinically meaningful reductions in exacerbations were observed in tezepelumab-treated patients with type 2-high and type 2-low disease by multiple definitions. Tezepelumab reduced exacerbation-related hospitalization or emergency department visits and improved secondary outcomes compared with placebo overall and across subgroups. The incidence of adverse events was similar between treatment groups. Conclusions: Tezepelumab resulted in clinically meaningful reductions in exacerbations and improvements in other outcomes in patients with severe, uncontrolled asthma, across clinically relevant subgroups. Clinical trials registered with www.clinicaltrials.gov (NCT02054130 [PATHWAY], NCT03347279 [NAVIGATOR]).

[Criteria for evaluation of response to biologics in severe asthma - the Biologics Asthma Response Score (BARS)]. / Kriterien zur Evaluation des Ansprechens auf Biologika bei schwerem Asthma ­ der Biologics Asthma Response Score (BARS).

BACKGROUND: The introduction of monoclonal antibodies (biologics) has revolutionized the therapy of severe asthma. Even though there is a response in the majority of patients, the degree of response varies. To date criteria for assessment of response to biologics are not consistently defined. AIM: To define criteria for evaluation of response to biologics that are precise, simple and suitable for daily use in order to guide decision-making regarding continuation, switching or stopping of biological therapy. METHODS: 8 physicians with large experience in this indication, supported by a data-scientist, developed a consensus on criteria to evaluate response to biologics in patients with severe asthma. RESULT: We developed a combined score based on current literature, own experience and practicability. It uses the main criteria exacerbations, oral corticosteroid (OCS) therapy and asthma control (asthma control test, ACT). We defined thresholds for "good response", "response" and "insufficient response" rated with a score of "2", "1" and "0" respectively: annual exacerbations ("0 or reduction ≥ 75 %", reduction 50-74 %", "reductio  < 50 %"), daily OCS dose ("stopping or reduction ≥ 75 %", "reduction 50-74 %", "reduction < 50 %"), asthma control (ACT increase ≥ 6 or ≥ 3 with result ≥ 20", "ACT increase 3-5 with result < 20", "ACT increase < 3"). Additional individual criteria like lung function and comorbidities may be important for evaluation of response. We propose 3, 6 and 12 months timepoint for assessment of tolerability and response. Using the combined score, we developed a scheme to guide the decision whether switching the biologic should be considered. CONCLUSION: The Biologic Asthma Response Score (BARS) serves as objective and simple tool to evaluate response to biologic therapy using the three main criteria exacerbations, OCS use and asthma control. A validation of the score was initiated.

Inhaled anti-TSLP antibody fragment, ecleralimab, blocks responses to allergen in mild asthma.

BACKGROUND: Thymic stromal lymphopoietin (TSLP) is a key upstream regulator driving allergic inflammatory responses. We evaluated the efficacy and safety of ecleralimab, a potent inhaled neutralising antibody fragment against human TSLP, using allergen inhalation challenge (AIC) in subjects with mild atopic asthma. METHODS: This was a 12-week, randomised, double-blind, placebo-controlled, parallel-design, multicentre allergen bronchoprovocation study conducted at 10 centres across Canada and Germany. Subjects aged 18-60 years with stable mild atopic asthma were randomised (1:1) to receive 4 mg once-daily inhaled ecleralimab or placebo. Primary end-points were the allergen-induced change in forced expiratory volume in 1 s (FEV1) during the late asthmatic response (LAR) measured by area under the curve (AUC3-7h) and maximum percentage decrease (LAR%) on day 84, and the safety of ecleralimab. Allergen-induced early asthmatic response (EAR), sputum eosinophils and fractional exhaled nitric oxide (F ENO) were secondary and exploratory end-points. RESULTS: 28 subjects were randomised to ecleralimab (n=15) or placebo (n=13). On day 84, ecleralimab significantly attenuated LAR AUC3-7h by 64% (p=0.008), LAR% by 48% (p=0.029), and allergen-induced sputum eosinophils by 64% at 7 h (p=0.011) and by 52% at 24 h (p=0.047) post-challenge. Ecleralimab also numerically reduced EAR AUC0-2h (p=0.097) and EAR% (p=0.105). F ENO levels were significantly reduced from baseline throughout the study (p<0.05), except at 24 h post-allergen (day 43 and day 85). Overall, ecleralimab was safe and well tolerated. CONCLUSION: Ecleralimab significantly attenuated allergen-induced bronchoconstriction and airway inflammation, and was safe in subjects with mild atopic asthma.

Long-term safety and efficacy of tezepelumab in people with severe, uncontrolled asthma (DESTINATION): a randomised, placebo-controlled extension study.

BACKGROUND: Tezepelumab is a human monoclonal antibody that blocks thymic stromal lymphopoietin. The drug has been tested previously in the phase 3 NAVIGATOR (NCT03347279) and SOURCE (NCT03406078) studies, and was subsequently approved as a treatment for severe asthma. This extension study recruited from NAVIGATOR and SOURCE and aimed to evaluate the long-term safety and efficacy of tezepelumab in individuals with severe, uncontrolled asthma. METHODS: DESTINATION was a phase 3, multicentre, randomised, double-blind, placebo-controlled, long-term extension study. The study was done across 182 sites (including hospitals, clinics, medical centres, clinical trial centres, and private practices) in 18 countries. Participants (aged 12-80 years) were required to have good treatment compliance in the parent study. Randomisation was stratified by the parent study and all participants were re-randomised. Those who were previously randomised to receive tezepelumab in either parent study continued treatment of subcutaneous tezepelumab (210 mg every 4 weeks); those who were previously randomised to receive placebo in either parent study were re-randomised 1:1 to receive either subcutaneous tezepelumab (210 mg every 4 weeks) or placebo (every 4 weeks) using a randomisation list prepared by a computerised system. Total treatment duration (including the parent studies) was 104 weeks for all groups. Participants, investigators, and site staff were masked to treatment assignment. The primary endpoints were exposure-adjusted incidence of adverse events and serious adverse events and the secondary endpoint was the annualised asthma exacerbation rate; these were assessed from week 0 of the parent studies to week 104 of DESTINATION in all participants who were randomised and who received at least one dose of tezepelumab or placebo in either of the parent studies. The trial is registered with ClinicalTrials.gov, NCT03706079, and is closed to new participants. FINDINGS: Participants were recruited between Jan 7, 2019, and Oct 15, 2020. For individuals who initially received tezepelumab (n=528) in NAVIGATOR, incidence of adverse events over 104 weeks was 49·62 (95% CI 45·16 to 54·39) per 100 patient-years, compared with 62·66 (56·93 to 68·81) for those receiving placebo (n=531; difference -13·04, 95% CI -17·83 to -8·18). For serious adverse events, incidence was 7·85 (6·14 to 9·89) per 100 patient-years for individuals who initially received tezepelumab and 12·45 (9·97 to 15·35) for those who received placebo (difference -4·59, -7·69 to -1·65). In SOURCE, incidence of adverse events was 47·15 (36·06 to 60·56) per 100 patient-years for those who initially received tezepelumab (n=74) and 69·97 (54·54 to 88·40) for those who received placebo (n=76; difference -22·82, -34·77 to -10·01). For serious adverse events, incidence was 13·14 (7·65 to 21·04) per 100 patient-years for those who initially received tezepelumab and 17·99 (10·66 to 28·44) for those who received placebo (difference -4·85, -14·88 to 4·53). Tezepelumab reduced the annualised asthma exacerbation rate over 104 weeks compared with placebo. In participants initially from NAVIGATOR, the annualised asthma exacerbation rate ratio over 104 weeks was 0·42 (95% CI 0·35 to 0·51); in those initially from SOURCE, the ratio over 104 weeks was 0·61 (0·38 to 0·96). INTERPRETATION: Tezepelumab treatment was well tolerated for up to 2 years and resulted in sustained, clinically meaningful reductions in asthma exacerbations in individuals with severe, uncontrolled asthma. These findings are consistent with previous randomised, placebo-controlled studies and show the long-term safety and sustained efficacy of tezepelumab in individuals with severe, uncontrolled asthma. FUNDING: AstraZeneca and Amgen.