This research study is looking at how well a new combination of medicines, Fluticasone Furoate (FF), Umeclidinium (UMEC), and Vilanterol (VI), works for treating asthma in kids aged 12 to 17. Asthma is a condition that makes it hard to breathe because the airways in the lungs become narrow and swollen. The study will last 24 weeks and compare this new combination to an existing treatment of FF and VI to see if it improves lung function better.

To join, you should:

• Be aged between 12 and 17 years old.
• Have had asthma for at least one year, requiring daily inhaled medicines.
• Have asthma that is not well controlled, even with current treatment.

You cannot join if you have had serious lung issues like pneumonia recently or if you smoke. Your asthma should be stable, even if you've had a flare-up recently. The study involves regular check-ups and tests. It's important to discuss with your doctor and parents to ensure it's a good fit for you. There may be risks like side effects from the medication.