Some people with asthma need more than one long-term medicine to keep their symptoms under control. New inhalers that combine multiple medicines into a single device can make treatment simpler and reduce the number of inhalers a person uses each day.
One example is Trimbow. Trimbow contains three medicines in one inhaler to help control asthma symptoms and reduce flare-ups. You may hear this being called “triple therapy.”
Managing asthma can be challenging when symptoms continue despite treatment. Trimbow is designed for adults whose asthma is not well controlled with other inhaled treatments.
Continue reading to learn how Trimbow works, how it was studied, how to use it, and the benefits seen in clinical trials.
Trimbow Side Effects and Interactions: What to Expect and How to Manage Them
How Does Trimbow Work for Asthma?
Asthma is a long-term (chronic) lung condition that can make it hard to breathe. In people with asthma, the airways can become swollen and irritated. The muscles around the airways can also tighten, causing the airways to narrow. In addition, extra mucus can build up in the lungs. These changes can lead to symptoms such as coughing, wheezing, shortness of breath, and chest tightness.
The goal of asthma treatment is to reduce swelling and keep the airways open. This helps improve breathing and can lower the risk of asthma attacks.
Trimbow contains three medicines that work together in different ways:
- Beclomethasone dipropionate is an inhaled corticosteroid (ICS). It helps reduce swelling and irritation in the airways.
- Formoterol fumarate is a long-acting beta-2 agonist (LABA). As a bronchodilator, it helps relax the muscles around the airways, making it easier to breathe.
- Glycopyrrolate is an anticholinergic medicine, also called a long-acting muscarinic antagonist (LAMA). It’s also a bronchodilator that relaxes the muscles in the airways, but it works differently from formoterol. Together, they help keep the airways open.
Trimbow is not a rescue inhaler. It should not be used to treat sudden breathing problems or an asthma attack. People using Trimbow should continue to keep a rescue inhaler available in case they have sudden asthma symptoms. Contact your health care provider right away if your breathing problems worsen or your rescue inhaler does not seem to work as well as usual.
How Was Trimbow Studied for Asthma?
The FDA’s approval of Trimbow for asthma was based in part on two large clinical trials called TRIMARAN and TRIGGER. These studies looked at whether adding a third medicine (glycopyrrolate) to an inhaled corticosteroid and long-acting bronchodilator could help adults whose asthma was not well controlled.
The studies enrolled adults who had uncontrolled asthma despite using a combination of an ICS and a LABA. The qualified participants had experienced at least one asthma flare-up in the previous year that required treatment with oral steroids, an emergency department visit, or hospitalization.
Together, the two studies included more than 2,500 participants and lasted one year (52 weeks). Before the studies began, all participants completed a two-week run-in period using a two-medicine inhaler containing beclomethasone and formoterol. They were then randomly assigned to continue the two-medicine inhaler or switch to triple therapy with glycopyrrolate added. In the TRIGGER study, some participants were assigned to use beclomethasone and formoterol plus tiotropium as a separate inhaler. (Tiotropium is the same type of medicine as glycopyrrolate.) Neither the participants nor the researchers knew which treatment most participants were receiving. If a person had sudden trouble breathing, they were told to use their rescue inhaler.
Who participated in the studies?
The people who took part in the TRIMARAN and TRIGGER trials had similar characteristics when the study began. On average, participants were in their early 50s and had been living with asthma for about 25 years. Most were White, and a few people were Asian or of other races. There were more women (62%-63%) than men (37%-38%). They also had similar scores when comparing lung function (lung health) and overall asthma control. Most had experienced at least one asthma flare-up during the previous year.
What did the researchers measure?
The goal of the study was to look at two main outcomes:
- Lung function, measured using a breathing test called forced expiratory volume in one second (FEV1) (This test measures how much air a person can forcefully breathe out in one second.)
- Moderate and severe asthma flare-ups (exacerbations) over the 52-week study period
In these studies, a severe asthma flare-up was defined as worsening asthma that required treatment with oral or injectable corticosteroids for at least three days and could include an emergency department visit or hospitalization. A moderate flare-up involved worsening symptoms, reduced breathing measurements, increased rescue inhaler use, or an asthma-related medical visit that did not require oral or injectable corticosteroid treatment.
What Benefits Were Seen?
The TRIMARAN and TRIGGER studies found that people who used Trimbow generally had better lung function and fewer asthma flare-ups than those who used a two-medicine inhaler containing beclomethasone and formoterol.
One of the main goals of the studies was to measure lung function. After 26 weeks of treatment, people using Trimbow had greater improvements in FEV1 than those using the two-medicine inhaler. These results, shown in the table below, suggest that people using Trimbow were able to move more air out of their lungs compared with those using the two-medicine inhaler.
| Study | Trimbow (triple therapy: beclomethasone/ formoterol/ glycopyrrolate) | Two-medicine inhaler (beclomethasone/formoterol) | Difference |
| TRIMARAN | +185 mL | +127 mL | +57 mL |
| TRIGGER | +229 mL | +157 mL | +73 mL |
The TRIGGER study also compared Trimbow with a treatment plan that used beclomethasone and formoterol plus tiotropium in a separate inhaler. The results showed similar improvements in lung function between these two approaches.
Another main goal of the studies was to see if Trimbow could reduce asthma flare-ups over a year.
- In the TRIMARAN study, people using Trimbow experienced 15% fewer moderate and severe asthma flare-ups than those using the two-medicine inhaler.
- In the TRIGGER study, researchers observed a 12% reduction, although that difference was not statistically significant, meaning the researchers could not rule out the possibility that it occurred by chance.
In addition, people using Trimbow generally went longer before experiencing their first asthma flare-up during the study.
Overall, the study results suggest that adding glycopyrrolate to beclomethasone and formoterol can provide additional benefits for some adults with uncontrolled asthma. Compared with the two-medicine inhaler, Trimbow improved lung function (FEV1) and helped reduce the number of asthma flare-ups experienced during the studies.
Your results may vary from what was seen in studies. A health care provider can help you decide if Trimbow may be a good option for you.
How Do I Use Trimbow?
The typical dosage of Trimbow is two inhalations twice daily, once in the morning and once in the evening. Use Trimbow exactly as prescribed by your health care provider. Do not use more doses than prescribed.
Trimbow comes with detailed Instructions for Use. Read these instructions carefully before using the inhaler for the first time. Because Trimbow is an inhaler, it is important to use the correct technique to make sure the medicine reaches your lungs. If you feel unsure whether you’re using the inhaler correctly, ask your health care provider or pharmacist for guidance.
After each dose, rinse your mouth with water, and spit it out. Don’t swallow the water. This can help lower the risk of getting a fungal infection in your mouth or throat.
Will I Still Need Other Inhalers?
Yes. Even if you use Trimbow every day, you may still need a rescue inhaler for sudden breathing problems or asthma attacks.
Trimbow is a maintenance (controller) inhaler. It is designed to help prevent asthma symptoms and reduce flare-ups when used regularly. However, it does not work quickly enough to treat sudden breathing problems. For this reason, Trimbow should not be used as a rescue inhaler.
Your health care provider will prescribe a separate rescue inhaler to use if you have sudden symptoms such as wheezing, chest tightness, or shortness of breath. Be sure you understand when and how to use your rescue inhaler.
Contact your health care provider if you find yourself needing your rescue inhaler more often than usual. This may be a sign that your asthma is getting worse and that your treatment plan needs to be reviewed.
How Much Does Trimbow Cost?
The amount you pay for Trimbow will depend on factors such as your insurance status, plan coverage, pharmacy, and eligibility for any manufacturer savings programs.
Because Trimbow is a newer asthma treatment, coverage may vary across different insurance plans. Some plans may require prior authorization. If your health care provider prescribes Trimbow, your pharmacist can help you find out your out-of-pocket cost and whether any savings programs are available. You can also check with your insurance provider to learn whether Trimbow is covered under your prescription drug plan. If cost is a concern, talk with your health care provider about assistance programs or other treatment options.
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