TABLE III.

Key points and recommendations

1. A multiallergen IgE test is a biomarker for atopic asthma and should be collected for baseline characterization of study participants in all NIH- initiated clinical trials and prospective observational studies.

2. Measurements of total IgE and allergen-specific IgE antibodies are supplemental tests that can be used in baseline characterization of study participants.

3. Feno measured at a constant flow rate is a simple, safe, and reproducible biomarker for use in asthma clinical trials.

4. Although Feno values overlap among healthy, atopic, and asthmatic cohorts, Feno levels <25 ppb generally indicate lower likelihood of eosinophilic inflammation and responsiveness to corticosteroids. However, Feno cannot be used interchangeably with sputum eosinophilia as an outcome measure, given that therapeutics that reduce eosinophilic inflammation do not always affect Feno levels.

5. Measurement of Feno should be considered in clinical trials where effects on TH2 inflammation are being assessed.

6. Analysis of eosinophil counts in induced sputum identifies participants who have asthma with eosinophilic and noneosinophilic inflammatory phenotypes. Inflammatory phenotypes can predict response to treatment.

7. Analysis of blood eosinophils by automated CBC provides useful information to characterize study populations and potentially to monitor responses to anti-inflammatory therapy.

8. Urinary LTE4 is a validated marker of cysteinyl leukotriene activity and should be considered for incorporation in clinical trials of molecules that may directly or indirectly affect this pathway.

9. The measurement of cortisol suppression is used primarily as a biomarker to assess the systemic effect of inhaled or systemic corticosteroids on the hypothalamic-pituitary-adrenal axis.

10. HRCT is capable of making structural measurements of the airways and parenchyma.

11. Clinical trials should consider storing blood, sputum, and urine specimens in biobanks.

12. Efforts should be made to standardize procedures to harmonize sample collection for biorepositories from clinical trials.

13. Biomarkers hold considerable promise for advancing personalized medicine. Further research is necessary to establish the specific contributions of different biomarkers in differentiating asthma phenotypes and in predicting and monitoring treatment response.