By P.K. Daniel
Severe asthma is increasingly a priority for doctors, medical researchers, pharmaceutical companies, and – of course – patients.
The American Academy of Allergy, Asthma & Immunology (AAAAI) estimates the prevalence of severe asthma is 5-10 percent of all asthma patients. However, the percentage may be higher because additional studies reveal about 50 percent of asthma patients experience poorly controlled symptoms despite treatment. As a result, severe asthma patients experience high rates of emergency department visits, hospitalizations and school or work absenteeism.
Asthma specialists diagnose severe asthma when symptoms are not well controlled with inhaled corticosteroids (ICS), short- and long-acting beta2-agonists (SABA and LABA), leukotriene inhibitors such as montelukast, or long-acting muscarinic inhibitors (LAMA).
Lifestyle factors that can impact asthma – exercise, diet, stress and sleep, among others – are also evaluated and addressed.
If severe asthma is the diagnosis, then what’s the next step?
“That’s when you would look to biologic medications,” says Michael Blaiss, MD, executive medical director of the American College of Allergy, Asthma and Immunology (ACAAI) and clinical professor of pediatrics at the Medical College of Georgia in Augusta.
Coordinating Care For Better Results
In March 2016, Dr. Sydney Leibel and his colleague Bob Geng, MD, established the Severe Asthma Clinic at Rady Children’s Hospital in San Diego.
The clinic used a multidisciplinary approach allowing patients to meet one-on-one with an allergist, pediatric pulmonologist, pharmacist, social worker, respiratory therapist and registered nurse during the course of a two-hour visit – instead of a routine, hurried 15-minute doctor visit.
How has the multidisciplinary approach worked? Early results are positive, Dr. Leibel says. It has resulted in an 82 percent reduction in emergency department or urgent-care visits and an 88 percent reduction in hospitalizations among severe asthma patients at the clinic. Of the 43 pediatric patients in the clinic, 10 are on biologics.
“I think the results are positive due to the patient’s access to biologics and our approach that really tries to address patients’ needs,” Dr. Leibel says. “We all work together to help the patient get better.”
Adds Dr. Geng: “Patients feel more in tune with their asthma and they learn a lot more about their condition.”
What are biologics?
These medications, typically administered as an injection or infusion every 2-4 weeks, are designed to treat the source of symptoms, rather than the symptoms themselves. They target the cells and pathways that lead to allergic inflammation and breathing problems for people with asthma.
“Biologics really get to what we call precision or personalized medicine because they’re for different phenotypes – or characteristics – of asthma.” Dr. Blaiss says. “In treating severe asthma, different biologics block certain mediators, which are the chemicals released that can lead to inflammation related to asthma.”
The first biologic approved for asthma, omalizumab (Xolair), arrived in 2003. It blocks immunoglobulin E (IgE), the antibody that causes allergic reactions. It’s approved for patients 6 years of age and older. The dosage and frequency vary based on the patient’s weight and levels of IgE.
“Xolair has been successful for patients with severe asthma that’s not well controlled with the combination of ICS and LABAs,” says pediatric allergist and immunologist Sydney Leibel, MD, co-director of the Severe Asthma Clinic at Rady Children’s Hospital in San Diego.
Newer biologics include mepolizumab (Nucala) and reslizumab (Cinqair), both of which block the chemical interleukin 5 (IL-5) to reduce the number of eosinophil blood cells that cause airway inflammation. Mepolizumab is for patients ages 12 years and older and is being studied as a self-injectable medication, while reslizumab is administered as an infusion for patients 18 and older.
Pending FDA approval, Dupilumab will be the first biologic approved for atopic dermatitis/eczema treatment; it is also being studied for asthma. Fevipiprant, the first asthma biologic given as a pill, is in clinical trials.
“Certain patients with severe asthma respond extremely well to biologics,” Dr. Blaiss says. “These patients experience a gradual reduction in asthma and allergy symptoms. Biologics can make an unbelievable difference.”
Reviewed by Bradley Chipps, MD and Stanley Fineman, MD