Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not recruiting

Study on Allergenic Extracts of Mites and Histamine Dihydrochloride for Allergy Patients

Fast replyInvestigational
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying allergies caused by certain types of mites. The trial will use skin-prick tests, which involve applying a small amount of a substance to the skin to see if it causes a reaction. The substances being tested include extracts from different types of mites: Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, and Lepidoglyphus destructor. These extracts are compared to a solution of histamine dihydrochloride, which is commonly used in allergy testing.

The purpose of the study is to determine the biological activity of these mite extracts in patients who are sensitive to them. This means the study aims to find out how strong the reaction is when these extracts are used in a skin-prick test. The study will involve applying these extracts to the skin and observing the size of the reaction, or wheal, that forms. This will help in standardizing the extracts in terms of their biological activity, measured in Histamine Equivalent Units (HEP).

Participants in the study will undergo skin-prick tests with the mite extracts and the histamine solution. The size of the skin reaction will be measured to assess the potency of the extracts. The study will also monitor for any adverse reactions to ensure safety. The trial is designed to help improve the understanding and standardization of allergy testing for these specific mite allergens.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment is conducted to confirm eligibility. This includes reviewing medical history and confirming sensitization to specific allergens through a skin prick test or specific IgE serum test.

  2. Step 2

    Skin-prick test administration

    The skin-prick test involves administering solutions containing allergenic extracts of mites and a histamine dihydrochloride solution. The solutions are applied subcutaneously, which means they are injected just under the skin.

    The allergens tested include Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, and Lepidoglyphus destructor. The histamine dihydrochloride solution is used as a control to compare the size of the skin reaction.

  3. Step 3

    Observation and measurement

    After the administration of the skin-prick test, the size of the wheal (a raised, red area on the skin) is measured. This helps determine the biological activity of the allergenic extracts.

    The primary endpoint is the area of the wheal produced by the allergenic extracts compared to the histamine control.

  4. Step 4

    Safety monitoring

    Throughout the study, safety is monitored by observing any adverse reactions that may occur. This includes any unexpected skin reactions or other symptoms.

  5. Step 5

    Completion of study

    The study is estimated to conclude by November 30, 2024. At the end of the study, the data collected will be analyzed to determine the biological potency of the allergenic extracts.

Who can join the trial?

8 criteria

  • Patients must be between the ages of 18 and 65, including both ages.
  • Patients must agree to participate by signing a consent form.
  • Patients should have a previous medical history that confirms they have an allergy.
  • Patients must show a reaction to certain allergens, which are substances that can cause an allergic reaction. This can be shown by:
  • A skin prick test, which is a test where a small amount of allergen is placed on the skin to see if there is a reaction. A positive result is when the reaction is at least 3 mm in size compared to a negative control.
  • A specific IgE serum test, which is a blood test that measures the level of IgE antibodies to the allergen. A result of 3.5 kUA/L or higher is needed.
  • These tests must have been done within the last 18 months before joining the study.
  • Women who can become pregnant must have a negative pregnancy test. This applies to women from the start of menstruation until after menopause, unless they have had surgery to prevent pregnancy.

Who cannot join the trial?

4 criteria

  • Individuals with **allergies** to the substances being tested cannot participate. Allergies are when your body reacts negatively to certain things, like pollen or certain foods.
  • Participants must be within a specific age range, which is not specified here, but generally means they need to be of a certain age to join.
  • Both **male** and **female** participants are considered, but certain conditions might exclude someone based on gender-specific health issues.
  • People who are part of a **vulnerable population** are not included. This means individuals who might need special protection or care, like those with certain disabilities or health conditions.
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • Dermatophagoides pteronyssinus extract

    is an allergenic extract derived from the house dust mite Dermatophagoides pteronyssinus. It is used in the trial to determine its biological activity in patients who are sensitive to this specific allergen.

  • Dermatophagoides farinae extract

    is another allergenic extract obtained from the house dust mite Dermatophagoides farinae. This extract is tested to evaluate its ability to produce a skin reaction in sensitive individuals, similar to a histamine solution.

  • Blomia tropicalis extract

    is an allergenic extract from the mite Blomia tropicalis. The trial uses this extract to assess its potency in causing a skin reaction in patients who are allergic to this type of mite.

  • Lepidoglyphus destructor extract

    is an allergenic extract from the mite Lepidoglyphus destructor. It is included in the trial to measure its effectiveness in producing a skin response in individuals with allergies to this specific mite.

What is already known about the treatment

Histamine Dihydrochloride – This medication is administered through injection and is used in clinical trials to evaluate the biological activity of allergenic extracts in patients with allergies. It is currently being studied to determine its effectiveness in standardizing allergenic extracts of mites. The main therapeutic indication is to assess allergic reactions by comparing the size of skin reactions to those caused by histamine. At the molecular level, histamine dihydrochloride works by binding to histamine receptors, leading to increased vascular permeability and the formation of a wheal and flare reaction. It is classified pharmacologically as an antihistamine agent used primarily in allergy testing.

Investigated diseases

Allergies – Allergies are hypersensitive responses of the immune system to substances that are generally harmless to most people, known as allergens. Common allergens include pollen, dust mites, mold, pet dander, and certain foods. When exposed to an allergen, the immune system mistakenly identifies it as a threat and releases chemicals like histamine, leading to symptoms such as sneezing, itching, and swelling. Allergies can affect different parts of the body, including the skin, respiratory system, and digestive tract. The severity of allergic reactions can vary from mild irritation to more severe responses. Over time, exposure to allergens can lead to chronic conditions such as asthma or eczema.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2024-513834-40-01Protocol codeDIA-STA04080912-0124Estimated enrolment90 patientsSponsorDiater Laboratorio De Diagnostico Y Aplicaciones Terapeuticas S.A.

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

ClinicalTrials.eu

Every clinical trial in Europe, in plain language.

Explore the full ecosystem of clinical research in Europe.

Search trials

Legal notice · Published by CTIN POLAND sp. z o.o., ul. rtm. Witolda Pileckiego 67/109, 02-781 Warsaw, Poland · KRS 0001111334 · REGON 528919042 · NIP 9512598637

© 2026 Clinical Trials EU – European Clinical Trials Information Network

GDPR compliance, ISO 9001 and ISO 27001 certified (LL-C Certification)

On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).