Trelegy Ellipta partially is. It contains three active drugs, and one of them is an inhaled corticosteroid called fluticasone furoate. The other two components are not steroids. So Trelegy is not purely a steroid, but it does contain one.
What’s Inside Trelegy
Trelegy combines three medications into a single once-daily inhaler, each working through a different mechanism:
- Fluticasone furoate is an inhaled corticosteroid. It reduces inflammation in the airways by suppressing the immune cells and chemical signals that drive swelling, mucus production, and airway narrowing.
- Umeclidinium is a long-acting muscarinic antagonist. It relaxes the smooth muscle around your airways by blocking a specific nerve signal that causes them to tighten.
- Vilanterol is a long-acting beta agonist. It also relaxes airway muscles, but through a different pathway than umeclidinium.
The steroid component handles inflammation. The other two handle bronchoconstriction, the physical tightening that makes it hard to breathe. Together, the three drugs address both the underlying inflammatory process and the mechanical obstruction in conditions like COPD and asthma.
How the Steroid in Trelegy Differs From Oral Steroids
The fluticasone furoate in Trelegy is inhaled, which means it’s delivered directly to lung tissue rather than circulating through your entire body. Lab studies show that fluticasone furoate has the highest cellular accumulation and slowest clearance rate of any commonly used inhaled corticosteroid. That’s actually a benefit: it stays active in the lungs longer, which is why Trelegy works with just one puff per day. But it also means relatively little of the drug reaches your bloodstream, so the widespread side effects associated with oral steroids (weight gain, bone thinning, blood sugar spikes) are far less of a concern.
That said, “less of a concern” is not the same as zero risk. Small amounts of any inhaled steroid do get absorbed systemically, especially at higher doses or over years of use.
Available Strengths
Trelegy comes in two strengths, and the difference between them is entirely the steroid dose. The standard version contains 100 micrograms of fluticasone furoate, 62.5 micrograms of umeclidinium, and 25 micrograms of vilanterol. The higher-strength version doubles the steroid to 200 micrograms while keeping the other two ingredients the same. The 100-microgram version is the usual starting dose for both COPD and asthma. The 200-microgram version is reserved for severe asthma that needs more aggressive inflammation control.
Side Effects Tied to the Steroid Component
Most of Trelegy’s steroid-related side effects are local, meaning they happen in your mouth and throat rather than throughout your body. The most common is oral thrush (candidiasis), a fungal infection that can appear as white patches on your tongue or the inside of your cheeks. Studies of patients using inhaled corticosteroids find thrush rates around 6%, though this varies with dose and individual immune function. Rinsing your mouth with water and spitting it out after each puff is the standard prevention step, and the FDA labeling for Trelegy specifically recommends this.
A more serious concern is pneumonia risk in people with COPD. Multiple large trials have found that COPD patients using inhaled corticosteroids develop pneumonia at notably higher rates. The landmark TORCH trial found pneumonia rates of roughly 19% in COPD patients using an inhaled steroid versus 12% on placebo. A pooled analysis of over 3,000 patients found that the specific combination of fluticasone furoate and vilanterol (two of Trelegy’s three ingredients) nearly doubled the odds of pneumonia and nearly tripled the odds of serious pneumonia requiring hospitalization. A Cochrane review of more than 30,000 COPD patients across 41 studies confirmed the pattern, finding a 78% increase in serious pneumonia events with fluticasone specifically.
The likely explanation is that high local concentrations of steroid in the lungs suppress the immune defenses that normally fight off respiratory infections. Fluticasone is particularly lipophilic, meaning it dissolves into and lingers in the lung lining longer than some other inhaled steroids, which may amplify this effect.
What Trelegy Is Approved For
Trelegy is FDA-approved for two conditions: maintenance treatment of COPD and maintenance treatment of asthma in adults 18 and older. In both cases, it’s a daily controller medication, not a rescue inhaler. It will not help during an acute breathing emergency, and you should keep a separate fast-acting rescue inhaler for those situations.
The triple-therapy approach is typically used when two-drug combinations aren’t providing enough symptom control. For COPD patients who still have frequent flare-ups on a two-drug regimen, adding the steroid component can reduce exacerbations. For asthma patients, the combination targets multiple mechanisms of airway obstruction at once, which can mean better day-to-day breathing with a single inhaler instead of juggling multiple devices.