The risk of SARS-CoV-2 infection and disease severity in a cohort of severe asthmatics treated with biologics

By Tarun Sai LomteReviewed by Danielle Ellis, B.Sc.Jun 29 2022

In a recent study published in The Journal of Allergy and Clinical Immunology: In Practice, researchers assessed the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in asthma patients taking biologics.

Background

The coronavirus disease 2019 (COVID-19) pandemic remains a major public health risk causing significant morbidity and mortality. The most common cause of mortality due to severe disease is associated with the involvement of the lungs, and perhaps why asthma and other respiratory diseases were considered as risk factors for severe COVID-19 early in the pandemic.

It was initially speculated that infection with SARS-CoV-2 would trigger asthma exacerbation because many viral respiratory infections are risk factors for asthma attacks. However, different studies have reported controversial findings on the risk of severe COVID-19 among asthma patients.

About the study

In the present study, researchers prospectively observed a cohort of severe asthmatic patients treated with biologics to assess the risk of infection with SARS-CoV-2 and the severity and outcomes of COVID-19. With the reports of initial COVID-19 cases in Greece in March 2020, respiratory physicians across the country were asked to provide data on asthma patients taking biologics. Eligible participants were adults with a confirmed diagnosis of severe asthma treated with biologics for four months at least.

Physicians prospectively followed up with patients (until April 2021) and tested them for SARS-CoV-2 if they presented COVID-19-associated symptoms. Data on COVID-19 severity, outcomes, and asthma deterioration were collected from positive cases. Besides, information on demographics, disease duration, forced expiratory volume in one second (FEV₁), treatments for asthma, and the type and duration of biologic therapy were collected from all participants.

They defined asthma exacerbation as the deterioration of asthmatic symptoms such as cough, dyspnea, chest tightness, or wheezing, requiring increased use of bronchodilators and antibiotic or systemic corticosteroid treatment. For hospitalized COVID-19 cases, they collected data on SARS-CoV-2-associated pneumonia, length of stay, admission to the intensive care unit (ICU), and mechanical ventilation requirement.

Results

Physicians from 23 clinics provided data on 591 patients with severe asthma. More than 63% of the subjects were females, and the mean age of participants was 57 years. The mean duration of asthma was 24 years. Most patients (60.6%) were treated with mepolizumab, 37.1% with omalizumab, and 2.4% with benralizumab. Over half the subjects were atopic; all omalizumab recipients were atopic, whereas 22.9% and 28.6% of mepolizumab and benralizumab recipients were atopic.

The average time of biologic treatment was 36 months. SARS-CoV-2 infection was recorded in 26 patients; nine were hospitalized due to the severe disease. Patients taking mepolizumab were significantly older, whereas omalizumab recipients had longer asthma duration with a longer period of biologic treatment and less frequently received long-acting muscarinic antagonists (LAMAs). 

COVID-19 cases had a shorter duration (12 months) of biologic therapy than naïve individuals (28 months). Nine cases were treated with omalizumab, one with benralizumab, and 16 with mepolizumab. Nine patients were admitted to the hospital due to severe disease, and eight were females. Hospitalized patients had a radiological and clinical manifestation of pneumonia and a longer asthma duration than non-hospitalized patients. All hospitalized cases were treated with mepolizumab, and one patient succumbed to COVID-19.

Biologic therapy was delayed for a week in two COVID-19 patients on mepolizumab treatment, per the physician’s decision. One of them was a male aged 71 years who showed clinical signs of asthma exacerbation. The patient was hospitalized and required oxygen supplementation. The other patient was a female aged 58 with exacerbation symptoms but did not require hospitalization. Biologic treatment was on-schedule in other COVID-19 cases. Additionally, three COVID-19 patients also showed asthma exacerbation but were not hospitalized.

Conclusions

The researchers observed that biologic therapy among asthmatics was not associated with a higher risk of infection with SARS-CoV-2. Nonetheless, if infected, they were at an elevated risk of hospitalization. They suggested that biologics should be administered per the original schedule irrespective of SARS-CoV-2 infection. COVID-19 cases constituted 4.4% of the study population, consistent with national estimates of 1.9% to 6.01%.  

In summary, these findings revealed that using biologics for severe asthmatic patients during the COVID-19 pandemic was safe and that COVID-19 was not as frequent among asthmatics treated with biologics as initially speculated. While few COVID-19 cases experienced asthma exacerbation, the disease did not result in loss of control.