Background: Phase 3 SIROCCO and CALIMA (SIR/CAL) studies enrolled adults with severe eosinophilic asthma (SEA) and ?2 exacerbations while treated with med/high-dosage ICS/LABA in the 12 months (mo) prior to baseline visit. Patients who completed SIR/CAL were enrolled in the BORA extension study to evaluate long-term efficacy and safety of benralizumab. Clinical remission (CR) has been demonstrated in patients with SEA treated with benralizumab for 12 mo in SIR/CAL, however longer-term data on durability of CR are needed.

Methods: This pooled post hoc analysis of BORA evaluated CR in patients treated with benralizumab for up to 24 mo. SIR/CAL patients with OCS use at baseline were excluded from this analysis. CR was defined as zero exacerbations, zero OCS use, a ?10% FEV1 decrease from the predecessor baseline, and an ACQ-6 score of <1.5. We evaluated the percentages of patients who achieved CR at the end of SIR/CAL and sustained CR after ?12 mo in BORA as well as patients who first achieved CR after 12 mo in BORA.

Results: Overall, 325 patients were included in this analysis. Among those, 104 who achieved CR at the end of SIR/CAL, whereas 221 patients did not achieve CR. Among patients who achieved CR at the end of SIR/CAL, 73% sustained CR during the 12 mo of treatment with benralizumab in BORA, whereas 26% of patients first achieved CR after an additional 12 mo of treatment in BORA.

Conclusions: In most patients with SEA who achieved CR in the first 12 mo of benralizumab treatment remained in CR with 12 additional mo of treatment. More than 25% of patients who did not achieve CR in first 12 mo of treatment, achieved CR with prolonged treatment with benralizumab.