The THARROS study

Who is this study for?

If you are living with COPD or have ongoing breathing difficulties and possible heart-related problems – even without a formal COPD diagnosis, this study might be relevant for you. Long term lung issues, especially when more severe can place extra strain on the heart. This increases the risk of serious health issues like worsening breathing, heart problems, hospital admissions, or death.

This study is investigating whether a new triple therapy inhaler can reduce this risk more effectively than current dual therapy inhalers.

We understand these conditions can significantly impact daily life, so we aim to make participation as easy as possible. If your study doctor approves, most of the follow-up visits can be done from home via video calls, and the study medication can be delivered to your home.

What is the potential treatment?

This study compares how well BGF, a triple therapy inhaler, and GFF, a dual therapy inhaler, can help prevent COPD flare-ups and serious heart events in people with COPD.

One option is BGF, a triple therapy inhaler that contains three different medicines. The other is GFF, a dual therapy inhaler with two medicines.

Both of these inhalers are already approved for treating COPD. However, neither is currently approved to help prevent serious heart events related to COPD.

The goal of this study is therefore to find out if the triple therapy works better than the dual therapy at reducing these risks.

You would take the treatment using an inhaler, just like the ones you may already be familiar with.

What treatments are given in the study?

Experimental Treatment: Triple Therapy Inhaler (BGF)

This inhaler combines three medicines that work together to make breathing easier:

• Budesonide – A corticosteroid that reduces inflammation in the lungs, helping to prevent flare-ups and ease breathing.

• Glycopyrronium – Relaxes the muscles around the airways and makes it easier to breathe.

• Formoterol fumarate – Works in the same way and helps improve airflow and reduce breathlessness.

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Control group: Dual Therapy Inhaler (GFF)

This inhaler contains two medicines that mainly help open the airways:

• Glycopyrronium – Relaxes airway muscles, making breathing easier.

• Formoterol fumarate – Works similarly to improve airflow and reduce shortness of breath.

The key difference is that the triple therapy includes an additional medicine to reduce lung inflammation.

How is the study designed?

All participants will start by using the dual therapy inhaler (GFF) for the first two weeks. This is the run-in period to ensure all participants begin from the same baseline. To join the study, you must switch from your usual COPD medications to GFF starting at your first visit.

The study is double-blinded, which means neither you nor your doctor will know which treatment you're receiving. In case of an emergency, your doctor can access that information.

You will take part in 11 study visits.

After the run-in period, a computer will randomly assign participants to one of two groups:

• Continue with GFF (dual therapy)

• Switch to BGF (triple therapy)

There is a 50% chance of receiving the experimental treatment (BGF).

The study has 3 steps:

Visit 1 – Screening: A screening visit with tests to make sure you meet the study requirements and that participation is safe. Includes a physical exam, lung function test, blood tests, and vital signs. Duration: up to 4 hours.

Visits 2–10 – Treatment: The study doctor will check your health, current medications, and inhaler technique. Visit 2 may last up to 4 hours; the others usually take about 1 hour. Duration: up to 3 years total.

Visit 11 – Follow-up: The study doctor will review your health and medications after the treatment ends. Duration: around 1 hour, plus a follow-up phone call 4 weeks later.

Total duration of the study: Around 3 years.

Benefits of Participation

• Travel costs to the study site will be reimbursed

• You will receive the study treatment and all medical tests free of charge

• Your health will be monitored closely by a study doctor

• You are helping advance research to improve COPD treatments

• Participation is voluntary, and you can withdraw at any time

Tests and Procedures

If you participate, you will undergo:

• Review of medical history

• Physical exam

• Medication review

• Lung function test (spirometry)

• Blood tests (eosinophils, cholesterol, blood sugar, kidney function)

• Blood pressure measurement

• Height and weight

• Pregnancy test (if applicable)

• CT scan (if needed)

• Symptom questionnaire (CAT score)