QUARTZ: Comparative Effectiveness of Switching From Albuterol to Albuterol/Budesonide Versus Adding Low-dose ICS or LTRA to Albuterol (QUARTZ)

August 21, 2026 updated by: AstraZeneca

QUARTZ: Comparative Effectiveness of Switching From Albuterol to Albuterol/Budesonide Versus Adding Low-Dose Inhaled Corticosteroids or Leukotriene Receptor Antagonists to Albuterol Among Adults With Asthma in the United States

The QUARTZ study is a retrospective observational cohort study using a prevalent new-user design and U.S. healthcare claims data to evaluate treatment effectiveness among patients with asthma. The study compares the real-world effectiveness of switching from albuterol-only rescue therapy to albuterol/budesonide versus adding low-dose inhaled corticosteroids (ICS) or leukotriene receptor antagonists (LTRA) while continuing albuterol. The primary objective is to assess the comparative effectiveness of these treatment strategies in reducing severe asthma exacerbations in routine clinical practice in the United States.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Observational

Enrollment (Estimated)

2669

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Adults asthma patients

Description

Inclusion Criteria:

  • Asthma patients with at least one prescription record (identified by NDC or Healthcare Common Procedure Coding System [HCPCS] codes) for Airsupra (Airsupra cohort), LD ICS or LTRA, (comparator cohort) since January 2023.
  • Patients with at least one prescription record (based on NDC or HCPCS codes) of albuterol within the 12 months prior to the first Airsupra or the controller medications prescription date
  • Patients aged ≥18 years on the index date
  • Patients with ≥12 months of continuous insurance enrolment prior and 12 months after index date.

Exclusion Criteria:

  • Patients with at least one medical claim with an ICD-10 code within the 12 months prior to the index date for any of the chronic respiratory conditions or systemic inflammatory diseases routinely treated with systemic corticosteroids (SCS)
  • Patients with any prescription record for any ICS or other controller therapies (including SAMA, LABA, LAMA, LTRA, theophylline or biologics) within the 12 months prior to the and inclusive of index date (the index therapy defining cohort entry (LD ICS for the LD ICS cohort; LTRA for the LTRA cohort is permitted on the index date)
  • Patients with maintenance OCS use within the 12 months prior to and inclusive of the index date
  • Airsupra patients with a concomitant SABA prescription record on the index date

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Airsupra cohort
Patients who switch from albuterol to Airsupra (albuterol/budesonide) as their rescue therapy.
Not applicable since it's an observational study. There are three study cohorts: 1) Airsupra cohort 2)Albuterol and low-dose ICS comparator cohort and 3) Albuterol and LTRA comparator cohort.
Other Names:
  • Observational study
Albuterol and low-dose ICS comparator cohort
Patients who add low-dose inhaled corticosteroid (ICS) to their ongoing albuterol rescue regimen.
Not applicable since it's an observational study. There are three study cohorts: 1) Airsupra cohort 2)Albuterol and low-dose ICS comparator cohort and 3) Albuterol and LTRA comparator cohort.
Other Names:
  • Observational study
Albuterol and LTRA comparator cohort
Patients who add leukotriene modifiers (LTRA) to their ongoing albuterol rescue regimen.
Not applicable since it's an observational study. There are three study cohorts: 1) Airsupra cohort 2)Albuterol and low-dose ICS comparator cohort and 3) Albuterol and LTRA comparator cohort.
Other Names:
  • Observational study

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Severe exacerbations during follow-up: annualized asthma exacerbation rates (AAER) by cohort, overall and by setting (IP, ED/urgent care, outpatient); plus absolute rates and rate ratios comparing Airsupra with each comparator cohort
Time Frame: Follow-up starts the day after index and ends at the earliest of death, data end, insurance disenrollment, loss to follow-up, or switch to the alternative rescue treatment, up to 36 months; add-on maintenance therapy does not censor follow-up.
To describe and compare the occurrence of severe exacerbations observed among the Airsupra cohort and each comparator cohort.
Follow-up starts the day after index and ends at the earliest of death, data end, insurance disenrollment, loss to follow-up, or switch to the alternative rescue treatment, up to 36 months; add-on maintenance therapy does not censor follow-up.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Time to first severe exacerbation: KM curves, median time by arm (if estimable), and Cox PH HRs comparing Airsupra with each comparator. Also, the proportion with at least 1 severe exacerbation at 3, 6, 9, and 12 months after treatment initiation.
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
To describe and compare the time to first severe exacerbation among the Airsupra cohort and each comparator cohort.
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
Cumulative inhaled corticosteroid exposure (beclomethasone equivalent µg/year)
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
To describe exposure to corticosteroid treatments among the Airsupra cohort and each comparator cohort
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
Cumulative systemic corticosteroid exposure (prednisone equivalent mg/year)
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
To describe exposure to corticosteroid treatments among the Airsupra cohort and each comparator cohort
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
Total SCS exposure days
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
To describe exposure to corticosteroid treatments among the Airsupra cohort and each comparator cohort
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
SCS burst rates
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months
To describe exposure to corticosteroid treatments among the Airsupra cohort and each comparator cohort
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Follow-up HCRU rates by arm: all-cause, asthma-related, and exacerbation-related use, including IP admissions, ED/urgent care, primary care, specialist outpatient visits, plus chest X-rays, oxygen treatment, and spirometry.
Time Frame: Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months.
To describe healthcare resource use (HCRU) among the Airsupra cohort and each comparator cohort.
Follow-up period for each patient starts the day after the index date and ends at the earliest date of death, end of data, end of insurance enrollment, loss to follow up, or switch to the alternative rescue treatment up to 36 months.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

August 3, 2026

Primary Completion (Estimated)

September 30, 2026

Study Completion (Estimated)

September 30, 2026

Study Registration Dates

First Submitted

August 3, 2026

First Submitted That Met QC Criteria

August 21, 2026

First Posted (Actual)

August 26, 2026

Study Record Updates

Last Update Posted (Actual)

August 26, 2026

Last Update Submitted That Met QC Criteria

August 21, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment:

https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

IPD Sharing Time Frame

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please refer to our disclosure commitment at: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

IPD Sharing Access Criteria

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe