Endotypes of Severe Asthma: 5 Questions on Pathways, Biomarkers, Biologics
Key factors in choosing appropriate biologic therapy for a patient with severe asthma include consideration of the specific mechanistic pathway that underlies the presentation, investigation of biomarker levels, and evaluation of comorbid inflammatory disease.
Following are 5 questions on these topics that are based on a comprehensive review and international expert opinion published in the Journal of Allergy and Clinical Immunology: In Practice by a group of clinicians recognized internationally for knowledge of severe asthma and of biologic medications. Test your endotype IQ.
1. True or False: Fraction of exhaled nitric oxide (FeNO) levels have demonstrated both prognostic and predictive value for patients with severe asthma.
Answer: A. True. A combination of blood eosinophil count (BEC) and FeNO levels provides additive information for biologic medications.
2. Before a biologic medication is initiated for severe asthma, a 4-phase baseline assessment is recommended to accomplish which of the above?
Answer: E. All the above. GINA and European Academy of Allergy and Clinical Immunology recommendations state that biologic therapy can be used in patients with severe asthma who show typical biomarkers of T2 airway inflammation.
3. True or False: There is strong evidence to support efficacy of biologics for patients with persistently low BEC (<150 cells/μL) and FeNO levels who are not receiving systemic corticosteroids.
Answer: B. False. There is no evidence to support efficacy of biologic therapy in patients with persistently low BEC (<150 cells/μL) and FeNO levels who are not receiving systemic corticosteroids.
4. What is recommended as the first choice for the treatment of patients with BEC ≥150 to ≤1500 cells/μL and severe atopic dermatitis?
Answer: C. Anti-IL-4/13. Consider T2 comorbid disease entities along with BEC and FeNO levels in choosing treatment for patients with BEC ≥150 to ≤1500 cells/μL and severe atopic dermatitis.
5. True or False. For patients with BEC >1500 cells/μL, potential reasons for this elevation should be determined before a treatment decision is made.
Answer A. True. Hematologic conditions and other hypereosinophilic conditions should be ruled out. If there is no alternative explanation for the eosinophilia, treatment with anti-IL-5/5Rα is recommended.
