This study is a Study to Understand How to Better Match Allergy Shots to a Child's Unique Mite Allergy Profile

1. Why is this study being done? For many children, tiny house dust mites are a major cause of persistent allergies, leading to uncomfortable symptoms like a stuffy nose, sneezing, and even asthma. A common long-term treatment is allergy shots, also known as allergen immunotherapy (AIT). These shots work like a vaccine, slowly training the body's immune system to stop overreacting to mites. However, not every child responds to this treatment in the same way. The investigators now know that children can be allergic to different parts of the dust mite. While most treatments focus on the most common parts (called "major allergens"), some children are allergic to other, less common parts (called "intermediate or minor allergens").

   The EXPLORER study wants to find out if a child's unique allergy profile-meaning which specific mite proteins they are allergic to-affects how well they respond to allergy shots. Our goal is to move away from a "one-size-fits-all" approach and toward more personalized care for children with dust mite allergies.

2. Who is this study for? The investigators are looking for children and teenagers (ages 5 to 18) in China who have a confirmed dust mite allergy and are planning to start allergy shots.

3. What will happen during the study? This is an "observational" study, which means the investigators will simply observe and track the progress of children who are already receiving a standard, approved allergy shot treatment as part of their regular medical care. The investigators won't be testing a new drug.

   Here's what participation involves:

   A Detailed Allergy Test: At the beginning, participants will have a special blood test. This test will look for allergies to nine different specific parts of the dust mite, giving us a very detailed map of their allergy.

   Grouping: Based on the results of this test, participants will be placed into different groups according to their specific allergy patterns.

   Tracking Progress: The investigators will follow their treatment journey for three years. The investigators will collect information at regular check-ups (at 0, 3, 6, 12, 24, and 36 months) on:

   How well their symptoms are controlled. How much allergy medication they need. Their overall quality of life. Any side effects from the shots. Annual Blood Tests: Once a year, the investigators will repeat the detailed blood test to see how their immune system is changing in response to the treatment.

4. What do the investigators hope to learn? The investigators have a main theory, or hypothesis: Children who are allergic to many different parts of the dust mite (including the minor ones) will show greater improvement from the allergy shots, compared to children who are only allergic to the most common parts.

   By studying a large group of 1,000 children, the investigators hope to provide clear evidence that can help doctors choose the right treatment for the right child. This will help fill a current gap in medical guidelines and bring us closer to truly personalized treatment for pediatric allergies.

5. Why is this study important? This is the first large-scale study of its kind in a real-world setting. The results could change how doctors diagnose and treat dust mite allergies in children. Instead of just knowing a child is allergic to mites, the investigators will be able to see the full picture of how they are allergic. This knowledge will help ensure that every child receives the treatment that gives them the best chance for long-term relief.

Inclusion Criteria:

-(1) Age: 5 years ≤ age < 18 years; (2) 1) Allergic rhinitis caused by Dermatophagoides pteronyssinus and/or Dermatophagoides farinae; 2) Or serum specific IgE ≥ 0.70 (kU/L) (for D. pteronyssinus and/or D. farinae); (3) Children meeting criteria (2) must undergo allergen component testing; (4) If accompanied by bronchial asthma, asthma must be diagnosed according to the Guidelines for the Diagnosis and Prevention of Childhood Bronchial Asthma (2025 edition) and the patient's asthma symptoms must be confirmed as well-controlled.

(5) Receiving treatment with dual-mite (Dermatophagoides pteronyssinus and farinae) subcutaneous immunotherapy (SCIT).

Exclusion Criteria:

• (1) Participants and/or their parents/legal guardians are judged by the investigator to be unable to fully understand the study requirements, or to adhere to long-term treatment and identify adverse reactions (including but not limited to conditions such as cognitive impairment or mental illness); (2) Children with severe or uncontrolled asthma (FEV1 < 70% of predicted value) or with irreversible airflow obstruction; (3) Children using beta-blockers or angiotensin-converting enzyme inhibitors (ACEI); (4) Children with severe autoimmune diseases or immunodeficiencies, including AIDS, inflammatory bowel disease, etc., as well as those currently using immunosuppressants; (5) Children with severe cardiovascular diseases or malignant tumors; (6) Children with incomplete clinical data.

This study plans to recruit participants from multiple research centers across China between November 2025 and November 2028. The target population is children aged 5 to 18 years who have been confirmed as having dust mite allergy through allergen testing and are scheduled to receive subcutaneous specific immunotherapy with a dust mite dual-allergen preparation.

In the EDC system, only the data entry personnel at the principal investigator's site and sub-centers are permitted to input data, and only the data monitoring personnel are permitted to view it.