From:  UpToDate on eosinophils

 Key factors in selecting biologics.

Biomarker profile (The “endotype”)
Blood eosinophils and FeNOHigh levels suggest T2 inflammationDupilumab, mepolizumab, benralizumab, reslizumab
IgE levelsElevated IgE points towards allergic asthmaOmalizumab
Low eosinophils and IgEnon-T2 asthmaTezepelumab
Clinical phenotype and comorbidities
Allergic asthmaOmalizumab
Eosinophilic asthmaMepolizumab, benralizumab, reslizumab, dupilumab
ComorbiditiesBiologic that treats both asthma and conditions like atopic dermatitis, nasal polyps, or EGPA

EGPA: eosinophilic granulomatosis with polyangiitis; FeNO: fractional exhaled nitric oxide; T2: type 2.