*3.4. Anti-IL-17A mAbs*

Increased expression of the Th17-derived cytokine IL-17A has been observed in sputum, airway tissue biopsies, and serum from asthmatic patients [58–62] and was positively associated with a more severe asthma phenotype [59,63,64] and neutrophilic inflammation [65]. Considering that Th17-high patients are less sensitive or even unresponsive to ICS [59,66] and that asthma progression differs from more treatable Th2 types of the disease [67], developing an effective therapy targeting Th17/IL-17A axis would overcome a major unmet need in severe asthma.

A Phase II RCT [22] investigated the subcutaneously administered anti-IL-17A mAb CJM112 300 mg when added to existing therapy in patients with inadequately controlled moderate to severe asthma, with low serum IgE and BEC. The effect of CJM112 treatment on trough FEV1 was not different from PCB, but a significant (*p* < 0.05) improvement was observed in the ACQ6 score (mean difference (MD) −0.22 units (80%CI −0.41–−0.04)) and the ACQ7 score (MD −0.23 units (80%CI −0.40 to −0.06)) vs. PCB. A higher proportion of patients receiving CJM112 had a decrease of ≥0.5 units in the ACQ7 score compared with PCB (71.7% vs. 52.8%) [22].
