D1.142 - Clinical remission in long-term biological therapy of severe asthma

   Biological therapies have proven to be effective in severe asthma, particularly in reducing exacerbation rates, ameliorating symptoms' control and disease-related quality of life. However there is still little data on their long-term effects on remission of asthma.

   The aim of the study was to assess frequency of severe asthma remission upon biological treatment.

  We retrospectively analyzed 211 patients (140 women, 71 men; aged 19-77) with severe asthma, who completed at least 6 months of therapy with one of the available biological drugs (omalizumab, mepolizumab, benralizumab, dupilumab, tezepelumab). Response to therapy was assessed after 6, 12, 24 and 36 months. Clinical remission was defined as  clinical symptoms’ silencing (ACQ < 1,5) with normal spirometry (FEV1≥ 80% pred.), no need for systemic steroids and no exacerbations. 

   Clinical remission was found in 26% of patients after 6 months; 28% after 12 months; 34% after 24 months and 35% after 36 months of the therapy. The most commonly met criteria were: lack of exacerbations (60%-88% of group depending on time point) and no therapy with systemic steroids (62-76% of group). The least frequent was normalization of spirometry (34-41% of cases).

  The patients who achieved clinical remission were characterized by shorter history of asthma (p<0,01), higher FEV₁ (p<0.01) and miniAQLQ (p=0.05) at initiating of therapy, lower rates of: severe exacerbations requiring hospitalization (p=0.01) and chronic therapy with systemic steroids (p<0.001). There were no significant differences in remission rate between drugs used.

   Our results suggest that clinical remission of asthma may be achieved in a substantial portion of patients on biological therapy. The portion of good responders increases with duration of treatment. The group achieving remission had, at the enrolment, shorter history of asthma, higher FEV₁ and miniAQLQ as well lower rates of hospitalizations and chronic therapy with oral steroids. These variables could be considered as possible predictors of future good response to biologicals.