The Asthma Landscape in America
Asthma affects roughly 25 million people across the United States, cutting across every age group, income level, and region. Yet the burden is not evenly distributed. Children in urban neighborhoods, particularly Black and Hispanic communities, face disproportionately high rates of emergency room visits and missed school days. A recent randomized trial published in a major medical journal examined whether financial incentives combined with medication reminders could improve adherence among high-risk children. The results pointed to something clinicians have long suspected: support systems matter as much as the prescriptions themselves.
The treatment toolkit has expanded considerably. In April 2026, the FDA approved Breztri Aerosphere as the first triple-combination therapy in a single inhaler for asthma patients aged 12 and older. This builds on years of research into inhaled corticosteroids, long-acting beta-agonists, and long-acting muscarinic antagonists. Yet for people with severe or hard-to-control asthma, even triple therapy may not be enough. That is where clinical trials enter the picture.
Clinical trials for asthma in the U.S. fall into several broad categories. Some test entirely new molecules. Others investigate whether existing drugs approved for one condition might work for another. Still others explore treatment strategies: Can patients safely step down their medications? Does a biologic injected every six months work as well as one given every two weeks? The PrecISE study, sponsored by the National Heart, Lung, and Blood Institute, takes a precision medicine approach, matching specific treatments to subtypes of severe asthma based on genetic markers, eosinophil counts, and other biological signatures. With over 30 sites across the country, PrecISE represents one of the largest federally funded asthma research efforts in recent years.
Types of Asthma Clinical Trials You Might Encounter
Not all asthma studies look the same. Understanding the categories helps you know what to expect.
Biologic trials have dominated the severe asthma research space recently. These drugs target specific immune pathways, such as the eosinophilic inflammation that drives many cases of uncontrolled asthma. EXDENSUR (depemokimab), approved by regulators in late 2025, is one such biologic given as a subcutaneous injection every six months. Its clinical trials enrolled patients at hundreds of sites worldwide, including locations throughout the United States. For patients tired of biweekly or monthly injections, the extended dosing schedule offered a meaningful quality-of-life improvement.
Triple-therapy trials like the KALOS and LOGOS studies that supported Breztri's approval compare single-inhaler combinations against dual therapies. These studies matter because simplifying a treatment regimen—one inhaler instead of two or three—often leads to better adherence and fewer missed doses.
Strategy trials ask a different question. Instead of "does drug X work," they investigate "can we safely reduce medication without losing control." The TAPER study, for example, is examining whether patients on tezepelumab can scale back their background maintenance therapy while keeping symptoms stable. For patients who worry about long-term steroid use, these studies offer a compelling reason to participate.
Pediatric studies focus on children and adolescents, who metabolize drugs differently than adults and whose asthma often follows distinct patterns. The financial incentive trial mentioned earlier enrolled children aged 5 to 12 from a large mid-Atlantic health system. Electronic inhaler sensors tracked daily use, and families received text reminders and adherence feedback. The study revealed that small, gain-framed incentives—structured as rewards rather than penalties—could meaningfully improve medication adherence in populations that face significant barriers to care.
Phase IV and observational studies monitor drugs already on the market, gathering real-world data on long-term safety and effectiveness. These tend to be less intensive than Phase I, II, or III trials and may involve fewer clinic visits.
| Trial Type | Example | Typical Duration | Best For | Key Considerations |
|---|
| Biologic (Phase III) | Depemokimab studies | 12–24 months | Severe eosinophilic asthma | Regular injections; lab monitoring required |
| Triple Therapy | KALOS/LOGOS (Breztri) | 6–12 months | Moderate-to-severe asthma | Single inhaler convenience; may require washout period |
| Precision Medicine | PrecISE (NHLBI) | 16-week crossover periods | Severe, treatment-resistant asthma | Multiple treatment arms; extensive phenotyping |
| Strategy/Step-Down | TAPER (tezepelumab) | Up to 52 weeks | Severe asthma on biologics | Goal is medication reduction; close monitoring |
| Pediatric Adherence | Electronic sensor + incentives | 7 months | Children 5–12 with poor control | Behavioral focus; family-centered design |
| Phase IV/Post-Market | Real-world safety studies | Varies | Already approved treatments | Lower risk profile; fewer visits |
Finding a Trial That Fits
Most people begin their search on ClinicalTrials.gov, a federal database maintained by the National Library of Medicine. The site allows filtering by condition, location, age group, trial phase, and recruitment status. Typing "asthma" and your city or state into the search bar yields a list of studies actively recruiting participants. Pay attention to the "Recruitment Status" field: "Recruiting" and "Not yet recruiting" are the two you want to see. "Completed" or "Terminated" means the study is closed.
Academic medical centers are another gateway. Institutions like the University of Chicago Medicine, Cleveland Clinic, Mayo Clinic, and Johns Hopkins run dozens of asthma trials at any given time. Their websites typically maintain searchable trial databases, and many have dedicated research coordinators who can walk you through eligibility criteria over the phone.
Patient advocacy groups—the Asthma and Allergy Foundation of America and the Allergy & Asthma Network—also publish trial listings and educational materials. They tend to explain things in plainer language than government databases, which can be helpful when you are first orienting yourself.
Your own pulmonologist or allergist is often the most direct route. Many specialists serve as site investigators for clinical trials and can tell you whether a study at their institution might be a good match. Even if they are not running a trial themselves, they can usually refer you to a colleague who is.
What Happens When You Enroll
The enrollment process starts with informed consent. You will receive a document explaining the study's purpose, the procedures involved, the potential risks and benefits, and your rights as a participant. Take your time with this. Ask questions. A good research team will welcome them.
After consent, you go through screening. This might involve blood tests, lung function tests like spirometry, allergy testing, and a review of your medical history. Some people who want to participate do not qualify after screening, and that is normal. Trials have strict inclusion and exclusion criteria designed to protect participants and produce clear results.
For those who do qualify, the trial itself follows a schedule. Some studies require weekly visits; others might check in once every few months. You may receive the investigational drug, a placebo, or standard-of-care treatment, depending on the study design. Blinded trials mean neither you nor the research team knows which group you are in until the study ends.
Sarah, a 34-year-old teacher in Ohio with severe eosinophilic asthma, enrolled in a biologic trial after years of cycling through inhalers and oral steroids. "I was nervous about the unknown," she said, "but my asthma had already taken so much from me—missed work, canceled trips, nights in the ER. The trial gave me structured monitoring I had never had before. Even the placebo possibility felt worth it because I knew I was contributing to research that might help someone else."
Questions to Ask Before Signing Up
Walking into a conversation with a research coordinator prepared makes a difference. Here are practical questions to bring:
Does the study pay for travel or lodging if the site is far from home? Many trials provide reimbursement for mileage, parking, and sometimes hotel stays, though policies vary widely.
What happens after the study ends? Some trials offer an open-label extension where all participants receive the active drug. Others do not, and you may need to transition back to standard care.
How much time will this realistically require? Clarify the number of visits, their duration, and any at-home tasks like symptom diaries or peak flow monitoring.
What are the known side effects of the investigational treatment? For biologics, this might include injection site reactions, headache, or, rarely, allergic responses. For inhaled therapies, throat irritation or hoarseness are common.
Can I continue seeing my regular doctor? The answer is almost always yes. Clinical trials supplement your usual care; they do not replace it.
Regional Resources Across the United States
Asthma research happens in every region of the country. In the Northeast, Boston and New York host major academic centers with robust allergy and pulmonology divisions. The Mid-Atlantic, particularly around Maryland and Washington, D.C., benefits from proximity to the NIH campus in Bethesda. The Southeast has sites in Atlanta, Durham, and Nashville that focus on pediatric asthma given the region's higher prevalence of childhood cases. The Midwest, anchored by Chicago and Cleveland, has strong research networks through institutions like Northwestern and the Cleveland Clinic. On the West Coast, San Francisco, Los Angeles, and Seattle run trials that often emphasize environmental triggers and allergy-linked asthma. Texas, with its unique climate and allergen profile, has hubs in Houston and Dallas.
For those in rural areas, telemedicine components are increasingly common in asthma trials. The PrecISE study, for instance, incorporated remote monitoring tools that reduced the need for frequent in-person visits. Ask about virtual participation options when you contact a study site.
The decision to join a clinical trial is personal. It sits at the intersection of hope and pragmatism—hope for better symptom control, and the pragmatism of weighing risks against the status quo. The asthma research community in the United States is large and active, with new studies opening regularly. Finding the right one takes some digging, but the tools and people to help you are out there. Start with your doctor, browse ClinicalTrials.gov, and reach out to a research coordinator. Even one conversation can clarify whether this path makes sense for your situation.
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