Asthma is one of the major non-communicable diseases affecting all age groups. Even though genetic predisposition is one of the factors for the increased prevalence – urbanisation, air pollution, and environmental tobacco smoke contribute more significantly. Symptoms include shortness of breath, cough, and wheezing. The latest WHO Global asthma report 2018 says among the 1.3 billion Indian population about 6% of children and 2% of adults have asthma. On the whole, India has three times higher mortality and more than two times higher DALYs (Disability–adjusted life years) compared to the global proportion of asthma burden. Symptoms range from mild intermittent to severe persistent asthma that requires a high dose of inhaled glucocorticoid (GC) plus a second controller or continuous or near-continuous oral steroids.
New therapies and therapeutic targets are required for better control of symptoms and exacerbations in severe asthma patients and for avoiding adverse reactions caused by the administration of oral corticosteroids (OCS). This review highlights on latest technological and treatment advancements in treatment for various criticalities of asthma.
A landmark advance in the treatment of severe asthma is the availability of a handful of powerful biologics that block different branches of the T2 response and have been convincingly shown to improve asthma control and prevent exacerbations in patients with severe disease. It is now clear that the availability of these new medicines has changed the treatment landscape.
In asthma, biologics are referred to as monoclonal antibodies which bind to a specific determinant, for example, a cytokine or receptor. Owing to this selectivity, biologicals are ideal for “personalized” or “precision” medicine. The available monoclonal antibodies include omalizumab (anti-IgE); mepolizumab, reslizumab and benralizumab (anti-IL-5 pathways), and dupilumab (anti-IL-4/IL-13).
“The use of these T2-high interventions has led to significant reductions in asthma symptoms, a decreased frequency of exacerbations, and improved lung function in many patients,” explains Dr Sheetal Chaurasia, Consultant – Pulmonary Medicine, Manipal Hospital Whitefield
Approximately 10% of patients with asthma have severe disease and have symptoms and exacerbations despite treatment with maximal standard-of-care controller therapy. Severe Uncontrolled asthma contributes disproportionately to the overall burden and cost of asthma. Monoclonal antibodies that target IgE or type 2 (T2) cytokines (interleukin-4, -5, and -13) and their receptors improve disease control for many patients with severe asthma and are included in management guidelines.
The current biologic agents are unsuitable for many patients with severe asthma, particularly those with no allergic or noneosinophilic phenotypes. Thus, there remains an unmet need for new therapies that are effective in a broader population of patients.
TSLP-Thymic stromal lymphopoietin and epithelial cell-derived cytokine are important factors in the pathogenesis of asthma, driving T2 inflammation. Tezepelumab is a human Monoclonal Antibody that specifically binds to TSLP thus reducing biomarkers and cytokines associated with inflammation including blood eosinophils, airway submucosal eosinophils, IgE, FeNO, IL-5, and IL-13.
“FDA has approved Tezepelumab injection as an add-on maintenance treatment used to improve severe asthma symptoms when used with a patient’s current asthma medicine. It is also the first treatment for severe asthma that is not limited to a specific type of severe asthma. Patients had fewer Exacerbations, better Lung function, asthma control and health-related quality of life,” shares Dr Divya Shree, Consultant – Pulmonology, Manipal Hospital Jayanagar
Inhalation therapy is the cornerstone to manage all people with asthma. It is the safest, fastest, and most effective way to deliver the drug directly into the airways of asthma patients. All patients with asthma must receive inhalation therapy be it a bronchodilator beta-adrenergic agonist or muscarinic antagonist, or anti-inflammatory drugs such as inhaled corticosteroids.
Inhalation therapy can be delivered by different devices, mainly divided into PMDI, DPI, and nebulisers. Each of these devices has its advantages and drawbacks. Various factors contribute to poor adherence to inhaled inhalation treatment for asthma. Chronic nature of the diseases, myths associated with inhalers, lack of knowledge about the disease, false sense of wellbeing, and poor inhaler technique or some of the factors associated with poor adherence or compliance to inhalation therapy. Global initiatives for asthma guidelines and Indian guidelines discourage the use of oral medications for treating asthma.
“Inhalation therapy for asthma can save lives and reduce the suffering and economic loss associated with these very common diseases like asthma, and COPD, therefore, it is a must to widely use inhalation form in our treatment,” explains Dr K S Satish, Consultant – Pulmonology, Manipal Hospital Millers Road.
Technological advancement in treatment has made the management of asthma more effective with quick relief within a few minutes. The treatment is made target specific with rapid onset of action. The effort behind it is tremendous and it requires a sound understanding of the lung and its associated kinetic processes to overcome the complex challenges of the inhalation route of administration and other advanced forms of medications. Improved technology has made lives simpler for asthma patients.
