An observational study in Asthma, sponsored by Icahn School of Medicine at Mount Sinai. Completed at 5 sites in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-18.
Sponsored by Icahn School of Medicine at Mount Sinai · Observational
A retrospective and prospective observational study of asthma designed to determine real-world and molecular description of asthma according to treatment and type 2 biology
REGAIN is a retrospective and prospective asthma cohort study designed to determine real-world molecular description of asthma according to treatment and type 2 biology. The researchers will enroll 5 pre-specified groups of participants with asthma of specific interest for mechanistic analyses according to clinically determined type 2 inflammatory endotype and response to therapy with inhaled steroids and other inhaled controllers with or without asthma biologics. This study is conducted at asthma specialty programs at Mount Sinai National Jewish Health Respiratory Institute in New York and National Jewish Health, Denver, Colorado, USA. Participants with asthma meeting specific inclusion criteria were identified and enrolled by screening electronic medical records from pulmonary and allergy specialty programs. Targeted populations included 5 categories of asthma patients as outlined in Table 1 including the following: (1) patients with type 2 asthma with symptom control at time of enrollment (ACT > 20) on standard Global Initiative For Asthma (GINA) step therapy (n=200) (2) asthma managed on stable biological therapy (n=200), (3) type 2 asthma with prior treatment with at least 2 biological therapies, (n=60), (4) likely type 2 low asthma patients (n=200), (5) asthma patients scheduled to be started de novo on biological therapies (n=120), and (6) healthy participants (n=400). Healthy participants were recruited in New York and Denver by community advertising. An optional study component employing a mobile phone application, use of digital inhaler monitors, and home digital peak flow will contribute data regarding medication use and lung function in the community and collect environmental data impacting asthma using geolocation data.
3,921 studies on the registry are indexed under Asthma; 507 are open to participants now.
This study's enrollment of 1,075 is above the median of 150 across 970 observational studies indexed under Asthma.
Browse Asthma studies →Icahn School of Medicine at Mount Sinai is the lead sponsor of 764 studies on the registry; 181 are open to participants now.
Of its 121 completed or terminated interventional studies of FDA-regulated products, 82 (68%) have results posted.
Counted across the registry records on this site, refreshed daily.
Specific groups of asthma patients as outlined and healthy volunteers
Inclusion Criteria for Asthma Participants:
Clinical diagnosis of asthma verified by a specialist physician (allergist or pulmonologist) and one or more of the following:
Exclusion criteria for Asthma Participants:
Inclusion Criteria for Healthy Controls:
Exclusion Criteria for Healthy Controls:
Participants in this group must meet criteria for asthma diagnosis and type 2 asthma status (1) Exhaled nitric oxide (FeNO) \> 50 ppb at any clinical care time point (2) at least one blood eosinophil count (BEC) \> 300/uL at any clinical care time point (3) eosinophilia by induced sputum or bronchoscopy (\> 3%) if available historically, performed as part of clinical care) and be on inhaled step therapy according to the Global Initiative for Asthma 2018 Step Therapy 1-5 treatment. They can not be on chronic oral corticosteroids or biologic therapy and must have an Asthma Control test (ACT) of 20 or greater.
Participants with likely type 2 low asthma (exhaled nitric oxide-FeNO \< 25 ppb AND blood eosinophil count (BEC) \< 200/uL AND no eosinophilia by induced sputum or bronchoscopy if available historically or as obtained during clinical care. On inhaled step therapy according to the Global Initiative for Asthma 2018 Step Therapy 1-5 treatment. They cannot be on chronic oral corticosteroids or biologic therapy and can have any value for Asthma Control test (ACT)
Participants included in the stable biological cohort must meet criteria for asthma diagnosis. The patients must also be on biological therapy for at least 4 months at enrollment. These participants needed to have an ACT of 20 or greater at time of enrollment, or if ACT 16-19 but they had GINA symptom control level 1-2, then they are considered partly controlled and were included in this group.
Either 2 type 2 or type 2 low characteristics Asthma participants with uncontrolled asthma on inhaled therapy (Global Initiative for Asthma 2018) Any asthma control test score (ACT) Starting a clinically prescribed biologic therapy for asthma Not on another biologic therapy for at least 4 months
Either 2 type 2 or type 2 low characteristics. Participants included in this group must report prior biological treatment and having stopped treatment with at least 2 prior asthma biologics. They could be on or off biologic therapy at enrollment and have any level of asthma control by asthma control test and GINA at the time of enrollment.
Healthy individuals with no respiratory symptoms
Asthma disease subtypes
Description of asthma disease subtypes according to type 2 and non-type 2 biology and control or lack of control along a range of asthma treatments.
Time frame: 18 months
Number of responders versus non-responders
Control on GINA Step 1-5 therapy will be defined by an ACT \>20. Control on biological therapies will be defined by ACT \> 20, or if ACT 16-19, achieving "partly controlled" status in according to GINA, or achieving a 50% reduction in oral corticosteroid (OCS) dose if patient is OCS dependent.
Time frame: 6 and 18 months
Symptom status
The proportion of participants achieving or maintaining symptom control, exacerbation control, both of these, or those achieving clinical remission at 6 and 18 months among asthma subgroups
Time frame: 6 and 18 months
Documents are hosted by the registry — open the source record to download them.
Plan to share: Yes — Individual participant data that underlie the results reported in this article, after deidentification (text, tables, figures, and appendices).
Supporting information: Study protocol, Sap, Icf, Csr, Analytic code
This study is completed, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Icahn School of Medicine at Mount Sinai