Allergen avoidance is the first stage of treatment and is the only treatment for food allergy. Respiratory allergies are mainly treated with symptomatic drugs which alleviate the symptoms without any curative impact on the causes of the disease.
Immunotherapy is the sole available treatment targeting the causes of allergy.
Prescribed as first line therapy for respiratory allergy, symptomatic treatments reduce the severity of symptoms and counter the inflammation caused by allergic reactions. The effect of the symptomatic medication is brief, and to obtain relief they must be taken throughout the whole period of exposure to allergens, and in some cases even prior to such exposure. Side-effects of this medication include drowsiness and sedation impacting patients’ quality of life and productivity.
The market of symptomatic treatment for allergic rhinitis is estimated at $10 billion in the seven major markets1. However, the market has recently been affected by the patent expiry of most major symptomatic drugs, resulting in an increased generic competition and a decrease in prices. Total symptomatic allergic rhinitis sales are forecasted to remain flat until 20251.
According to IMS Health, sales of bronchodilators and asthma products reached $36.0 billion in 2010 and $39.4 billion in 2011, making these drugs the second largest therapy class in the world, just behind oncology drugs and ahead of anti-diabetic medications or lipid regulators. The recent entry of generics for Montelukast and LABA/ICS combinations will similarly erode this market.
Desensitisation, sometimes referred to as allergen immunotherapy (AIT) or specific immunotherapy or SIT, is the only treatment that resets the immune system, switching the immune response against the allergens from “abnormal” to “normal”.
It is currently the only treatment that targets the causes of allergy. It consists of administering progressively higher doses of allergens in order to restore normal functioning of the immune system. Immunotherapy is probably the best available alternative to current symptomatic treatment.
The classical AIT treatments make use of whole allergens extracted from natural sources, which can create variation in the potency from batch to batch resulting in inconsistency in safety and efficacy. As a consequence, the use of whole allergens often results in significant side-effects, including local and systemic allergic reactions, which, in extreme cases, could lead to anaphylaxis, hospitalisation and death.
Because of the risk of systemic allergic reactions at the time of the injection, current immunotherapy is a long and expensive treatment with cumbersome regimens. This leads to low patient acceptance and low treatment compliance. Only 50 % of the patients with poorly controlled allergy are accepting current immunotherapy treatments, of which only 30 % comply with the full treatment schedule.
Therefore there is need for a safe and effective immunotherapy treatment that would provide desensitisation for common respiratory and food allergens.
(1): Visiongain allergic rhinitis drugs market forecast 2015-2025