Introduction
Asthma affects millions worldwide, and while most people achieve good control with standard medications, a subset suffers from severe asthma that remains difficult to manage despite high-dose inhaled corticosteroids and other therapies. For these patients, biologic therapies—advanced, targeted treatments—offer new hope by directly addressing underlying inflammation mechanisms. This article explores what severe asthma is, how biologics work, and the options currently available.
What Is Severe Asthma?
Definition
Severe asthma is a form of asthma that:
- Requires high-dose controller medications to maintain control, or
- Remains uncontrolled despite optimal treatment adherence and management of triggers.
Impact
- Frequent symptoms and flare-ups
- Increased hospitalizations and emergency visits
- Reduced quality of life and daily functioning
Why Are Biologics Needed?
Traditional asthma treatments like inhaled corticosteroids reduce airway inflammation broadly but may not work well for everyone, especially those with specific inflammatory pathways driving their asthma.
Biologics are designed to target specific molecules or cells involved in the inflammatory process, providing a more precise approach. They are administered via injection or infusion, usually every few weeks.
How Do Biologics Work?
Biologics interfere with key components of the immune system that contribute to asthma, including:
- Immunoglobulin E (IgE): An antibody involved in allergic reactions.
- Interleukins (IL-4, IL-5, IL-13): Proteins that promote inflammation and attract immune cells to the airways.
- Eosinophils: A type of white blood cell that causes airway inflammation.
By blocking these targets, biologics reduce airway inflammation, improve symptoms, and lower the frequency of exacerbations.
Biologic Treatment Options for Severe Asthma
a) Omalizumab (Xolair)
- Target: IgE antibody
- Use: For allergic asthma with elevated IgE levels.
- Administration: Subcutaneous injection every 2–4 weeks.
b) Mepolizumab (Nucala)
- Target: IL-5 cytokine
- Use: For eosinophilic asthma (high eosinophil counts).
- Administration: Subcutaneous injection every 4 weeks.
c) Reslizumab (Cinqair)
- Target: IL-5 cytokine
- Use: For eosinophilic asthma.
- Administration: Intravenous infusion every 4 weeks.
d) Benralizumab (Fasenra)
- Target: IL-5 receptor
- Use: For eosinophilic asthma.
- Administration: Subcutaneous injection every 4–8 weeks.
e) Dupilumab (Dupixent)
- Target: IL-4 and IL-13 pathways
- Use: For moderate-to-severe eosinophilic or corticosteroid-dependent asthma.
- Administration: Subcutaneous injection every 2 weeks.
Who Is a Candidate for Biologics?
- Patients with severe asthma uncontrolled by high-dose inhaled corticosteroids and other controllers.
- Those with frequent exacerbations or hospitalizations.
- Patients with elevated blood eosinophils or IgE levels.
- Individuals with confirmed allergic or eosinophilic asthma phenotypes.
A thorough evaluation by an asthma specialist, including blood tests and lung function tests, is needed to determine eligibility.
Benefits and Considerations
Benefits
- Reduced asthma exacerbations
- Decreased need for oral corticosteroids
- Improved lung function and quality of life
- Fewer hospital and emergency visits
Considerations
- High cost and insurance approval requirements
- Need for regular injections or infusions
- Potential side effects: injection site reactions, headache, rare allergic reactions
- Close monitoring by healthcare providers
Conclusion
Biologic therapies represent a major advancement for patients with severe asthma who do not respond well to traditional treatments. By targeting specific immune pathways, biologics provide personalized care that can dramatically reduce symptoms, prevent attacks, and improve overall well-being. If you or a loved one struggles with severe asthma, discussing biologic options with an asthma specialist can open doors to better control and a better life.
FAQs
Are biologics a cure for asthma?
No, they control symptoms and reduce flare-ups, but do not cure asthma.
How soon do biologics start working?
Many patients notice improvement within weeks, but full benefits may take a few months.
Are biologics safe for children?
Some biologics are approved for children as young as 6 or 12, depending on the medication.
Can I stop other asthma medications if I start biologics?
Usually, biologics are added to existing therapy, not used alone—discontinue only under doctor guidance.
How are biologics administered?
Most are given as subcutaneous injections; one (reslizumab) is given intravenously.
