Real-life impact of anti-IL5 therapy on exacerbation types in patients with obstructive lung disease.

BACKGROUND

While anti-interleukin (IL) 5 therapy has been shown to be efficacious to reduce exacerbation rates (ERs) in patients with severe eosinophilic asthma and might also benefit patients with coexisting chronic obstructive pulmonary disease (COPD), it is unknown whether anti-IL5 therapy reduces all types of exacerbations in heterogeneous (smoking) real-life patients.

METHODS

Adults initiating mepolizumab or benralizumab between 2017 and 2019 were identified in Belgian nationwide data. The ER in the year before anti-IL5 therapy initiation was compared to the year after. Exacerbations were classified as severe (hospitalised) exacerbations or moderate (outpatient) exacerbations treated with antibiotics, oral corticosteroids (OCS) or the combination.

RESULTS

Among 807 patients initiating anti-IL5 therapy, severe ER was 40±4 exacerbations per 100 patient years pretreatment versus 17±3 post-treatment initiation (p<0.001, relative risk reduction (RRR) -56%, number needed to treat (NNT)=4) and significantly reduced both in patients without COPD (n=616, ERpre=15±2, ERpost=6±1, p<0.001, NNT=11) as with coexisting COPD (n=191, ERpre=119±12, ERpost=53±9, p<0.001, NNT=2). For moderate exacerbations, ERs were significantly reduced for all types of exacerbations in both patients with or without COPD, except for OCS only-treated exacerbations in patients with coexisting COPD (p=0.288). Current smoking reduced anti-IL5 effectiveness on OCS-treated exacerbations (NNT >1), although current smokers with coexisting COPD still had a great reduction in hospitalisations (ERpre=152±23, ER post=55±18, p<0.001, NNT=1, RRR=-64%).

CONCLUSIONS

In this nationwide cohort study, treatment targeting eosinophilic inflammation was significantly associated with reduced moderate and severe exacerbations, with seemingly less impact on corticosteroid-treated exacerbations in (current smoking) patients with coexisting COPD, but still a large number of hospitalisations were prevented.