Treatment of allergic diseases: eliminate the cause
Bronchial Asthma Control Tool
Maxim Russo, <url>A new anti-allergenic drug is undergoing the final stage of clinical trials.
It does not just allow you to remove the symptoms of diseases, but affects their causes, which lie in the work of the immune system. If the tests are successfully completed, millions of people will be able to breathe freely.
Studies show that from the 1960s to the 2000s, the incidence of bronchial asthma in the world has been continuously increasing. According to 2011 data, 235-330 million people suffer from bronchial asthma in the world, and approximately 250,000 - 345,000 people die from this disease every year. The incidence in different countries of the world can reach from 1 to 18%.
At the same time, it should be particularly noted that there are more asthma patients in Western Europe and North America than in developing countries in Africa and Asia. Asthma affects approximately 7% of the population of the United States, 5% of UK residents. And in Canada, Australia and New Zealand, the disease rate is even higher – about 14-15%.
The symptoms of the disease are well known. The patient has shortness of breath, wheezing, a feeling of stuffiness in the chest, cough. During an asthma attack, the branches of the patient's bronchi contract, and mucus begins to stand out intensively, which prevents free breathing. An attack of suffocation begins. Compression of the bronchi occurs due to the contraction of the smooth muscles surrounding them, and the muscles contract under the action of excitation of the parasympathetic nervous system.
Bronchi are normal and with an asthma attack
In principle, this is a normal reaction when something harmful enters the bronchi, which the body must urgently remove. In such cases, the immune system reacts first, the autonomic nerves are excited, smooth muscles contract, mucus is released, a person coughs, getting rid of the pathogen that has got inside. The picture, as we can see, is the same as with an asthmatic attack. Only an asthmatic attack occurs when the body does not need such emergency actions, it is a kind of false alarm. The bronchi of a person suffering from asthma show an increased, unnecessary ability to an acute allergic reaction. This reaction can be caused by various factors ("asthmatic triggers"): plant pollen, dust, some medications (for example, for so-called "aspirin asthma"), cooling, physical activity, and others.
Here we come to a hypothesis that may explain why asthma is now more prevalent in developed countries. This so-called hygienic hypothesis, first expressed in 1989. If earlier a person developed in close contact with many bacteria and other pathogenic factors, and his immune system had time to adjust accordingly to resist them, and with some to learn to live in peace. A modern child grows up in a clean room, he is taught to wash his hands with soap, treated with antibiotics, so the immune system does not receive the necessary "skills". In countries where the level of sanitation is lower, this does not happen. We have already mentioned the hygiene hypothesis, talking about the increase in cases of food allergies.
But this hypothesis may indicate the reasons for the increase in asthma cases, but it will not answer the question of what to do. Turning to the conversation about the fight against asthma, first of all it should be said that asthma therapy can be symptomatic and basic. Symptomatic is aimed at relieving an attack of suffocation. A variety of inhalers used by asthma patients just cause relaxation of smooth muscles, as a result of which the bronchi expand and it becomes easy for a person to breathe. But if you use only symptomatic therapy, the causes of asthma will not go away. Moreover, prolonged use of such drugs leads to a more severe course of the disease in the future.
This means that basic therapy is needed to control the causes of seizures, making adjustments to the work of the patient's immune system. One of the means of such asthma therapy is being developed by the biotech company Eleventa, a resident of the Skolkovo Foundation.
The new drug is called OC000459, patients receive it in the form of tablets. The "target" of the drug is the CRTh2 receptor, which is present in certain immune cells, the so-called T helper cells. The receptor is a protein complex of the cell surface that recognizes a certain molecule (antigen) by chemically binding to it. Having met the antigen, the T-helper activates other cells of the immune system, stimulating its activity. The substance prostaglandin D2 serves as an antigen for the CRTh2 receptor. It serves as a signal ("mediator of inflammation") for the activation of cells of the immune system and, consequently, an allergic reaction.
Somewhat simplistically, the events look like this. In response to the appearance of a trigger (allergen) The so-called mast cells (mastocytes) secrete prostoglandin D2. The CRTh2 receptor in T helper cells reacts to it. This attracts another type of cell – eosinophils, which secrete substances that damage the bronchial epithelium. Since all this immune reaction in asthma is harmful to the body, the chain of events should be interrupted. For example, by finding a substance that would react with the CRTh2 receptor itself, preventing it from reacting with prostaglandin. Biologists call such substances receptor antagonists. For the CRTh2 receptor, different researchers have proposed about ten antagonist substances. One of them, and apparently very effective, is the drug OC000459.
Having created the drug OC000459, the specialists of Eleventa started testing it. Recall that before a modern medicine receives official recognition, which will open the way for it to pharmacies, it must go through three phases of clinical trials. First, healthy volunteers are tested to see if the new drug is safe and see how it is absorbed by the body. The second phrase of clinical trials is already being conducted on patients – this is the first test of the effectiveness of a new drug and the selection of its dose. Finally, during the third phase, a large number of patients in various medical institutions participate in the clinical trial. The study is carried out by the "double-blind method", when neither the patient nor the doctor knows what the patient is taking in a particular case: the test drug or the control (placebo). The proven effectiveness of the drug in the third phase means the success of its creators, the appearance of a new drug and its entry into the market.
The drug OC000459 has already confirmed its safety. Also, according to the article by Sally E. Wenzel Tissue-Based and Bronchoalveolar Lavage-Based Biomarkers in Asthma, published in the journal Immunology and Allergy Clinics of North America, it showed a clinical effect in the treatment of asthma. In patients receiving it, the condition improved by 22% compared to the control group (the frequency of seizures decreased, the manifestation of asthma symptoms decreased). Also, the function of external respiration was statistically significantly improved by 2.2% in patients taking the studied drug. This is a very good result. In the summer of this year, Eleventa began the third registration phase of clinical trials of the drug OC000459.
The developers suggest that the drug OC000459 can also be used for other allergic diseases: allergic rhinitis, conjunctivitis, atopic dermatitis and eosinophilic esophagitis. It is important that, again, it does not just allow you to remove the symptoms of diseases, but affects their causes, which lie in the work of the immune system.
Yulia Moskot, CEO of Eleventa, emphasizes the demand for new drugs: "The high prevalence and increase in morbidity, especially in the children's part of the population, increase the need for doctors for an effective and safe tool for controlling bronchial asthma. A new drug capable of qualitatively influencing the course of chronic inflammatory and allergic processes, if effective and safe, will be in demand by patients who have difficulties controlling the disease with modern drug therapy."
"We hope that, if the clinical trial is successfully completed, we will be able to bring to market an effective drug that can improve the quality of life of millions of patients with bronchial asthma," says Moskot.
Portal "Eternal youth" http://vechnayamolodost.ru30.10.2014