Иммунотерапия аллергии: методы и эффективность лечения

Medical treatment for environmental allergies

Allergen immunotherapy, also known as desensitization or hypo sensitization, is a medical treatment for environmental allergies, such as insect bites, and asthma. Meta analyses have found that injections of allergens under the skin are effective in the treatment of allergic rhinitis in children and in asthma. The benefits may last for years after treatment is stopped. The evidence also supports the use of sublingual immunotherapy against rhinitis and asthma, but it is less strong. In this form the allergen is given under the tongue and people often prefer it to injections. Anaphylaxis during sublingual immunotherapy treatment has occurred on rare occasions. Severe side effects such as anaphylaxis during subcutaneous immunotherapy treatment are relatively uncommon. A detailed diagnosis is necessary to identify the allergens involved.

Subcutaneous immunotherapy (SCIT), also known as allergy shots, is the historical route of administration and consists of injections of allergen extract, which must be performed by a medical professional. Subcutaneous immunotherapy protocols generally involve weekly injections during a build up phase, followed by a monthly maintenance phase that consists of injections for a period of 3–5 years. The build up phase involves the patient being administered injections which contain increasing amounts of allergens about one to two times per week. The length of the build up phase is dependent upon how often injections are administered, but normally ranges from three to six months. After the effective dose is reached, the maintenance phase is implemented, which varies depending upon an individual's response to the build up phase. When accounting for a person's age, type of allergen, and severity of allergy, there is a high probability that subcutaneous allergen immunotherapy may provide greater clinical and immunological responses than sublingual allergen immunotherapy. Compared to sublingual allergen immunotherapy, there are no significant differences observed in quality of life. Subcutaneous allergen immunotherapy adverse events vary significantly depending on different allergenic extracts and the application of different allergen immunotherapy schedules. This effectiveness, however, varies depending on the type of allergen. Sublingual immunotherapy is used to treat allergic rhinitis, often from seasonal allergies, and is typically given in several doses over a 12 week period. It works best when given 12 weeks before the start of the pollen season. Long term, many study participants still experienced mild allergic reactions or needed to regularly consume the allergen to maintain desensitivity. Additionally, oral immunotherapy is known to have an increased risk in the probability of needing epinephrine in patients who take it. Currently, the U. S. Food and Drug Administration has not approved any oral immunotherapy agents for asthma. In January 2020, the FDA approved Palforzia for mitigating "allergic reactions, including anaphylaxis, that may occur with accidental exposure to peanuts." It is the first drug approved for peanut allergies. It will not allow allergic people able to eat normal amounts of peanuts, but helps prevent allergies due to accidental eating.

Transdermal immunotherapy (TDIT) involves skin induced suppression via epicutaneous (EC) application of an antigen in order to raise the threshold which triggers a reaction.

In desensitization immunotherapy the aim is to induce or restore tolerance to the allergen by reducing its tendency to induce IgE production. People are desensitized through the administration of escalating doses of allergen that gradually decreases the IgE dominated response. The objective of immunotherapy is to direct the immune response away from humoral immunity and toward cellular immunity, thereby encouraging the body to produce fewer IgE antibodies and more CD4+ T regulatory cells that secrete IL 10 and TGF β, which skews the response away from IgE production. Oral immunotherapy also creates an increase in allergen specific IgG4 antibodies and a decrease in allergen specific IgE antibodies, as well as diminished mast cells and basophils, two cell types that are large contributors to allergic reaction.

Reactivity is tested using oral food challenges or with skin prick tests. Phases 1 & 2 of sublingual immunotherapy are conducted in a supervised clinical setting. However, phase 3 can be done at home.

In the late 19th century and early 20th century, allergic conditions were increasingly attracting both medical attention (as an emerging public health problem) and scientific interest (aided by progress in biochemical techniques and the development of molecular and pathogenic theories). However, the many and varied treatment approaches were very unscientific. The British physicians Noon and Freeman were the first researchers to test pollen allergen immunotherapy in humans. Noon and Freeman, researchers at the Department of Therapeutic Inoculation at St. Mary's Hospital in London, published their findings in The Lancet in 1911. Building on the observations of his predecessors Bostock, Blackley and Dunbar, Noon noted that people with hay fever "sometimes become cured" and that this was possibly because they "have had the good fortune to develop an active immunity against the toxin." He hypothesized that by injecting people with hay fever with small amounts of a pollen "toxin", a state of immunity could be achieved. Allergen immunotherapy was part of mainstream medical practice for hay fever treatment in the 1930s.

Sublingual immunotherapy drops are currently commercialized and used in most European and South American countries, and in Australia and Asian countries. In most European countries, national regulations allow marketing of allergen products as "named patient preparations" (NPPs). In the United States, drop formulations have not yet received FDA approval, though off label prescription is becoming common. In 2014, the FDA approved a once daily sublingual tablet containing allergen extracts for the treatment of "hay fever" (allergic rhinitis with or without conjunctivitis).

The use of subcutaneous immunotherapy for treatment of environmental based allergies and asthma is well supported by the majority of national and international allergy groups such as the World Allergy Organization, Canadian Society of Allergy and Immunology, European Academy of Allergy and Clinical Immunology, and the American Academy of Allergy, Asthma and Immunology. The use of sublingual immunotherapy is supported by few allergy agencies in order to allow for more investigation to occur on its practical use. The FDA currently allows individual allergists to create the formula for each dosage, whereas the EMEA requires treatment extracts to be prepared at manufacturing sites. Communication about allergen immunotherapy is not described very often in the news media; it is usually only communicated by the science community. The scientific community describes allergen immunotherapy as a scientific solution that helps not only patients with allergies but also positively impacts the quality of life of them and others around them. As temperatures increase due to changing climates, pollen levels also increase. Allergies are becoming a more common problem among the public, which is why the science community advocates for allergen immunotherapy. Subcutaneous allergen immunotherapy, according to the scientific community, is an effective solution to allergies due to numerous positive studies.

as of 2015, oral immunotherapy's balance of risk to benefit for food allergies was not well studied.