In Vivo Assessment of Histamine Equivalent Prick Test Units for Phleum pratense and Dactylis glomerata Allergen Extracts in Allergic Patients
- Trial ID
- 2024-514215-98-00
- Protocol
- G110-STD-071
- Sponsor
- Inmunotek S.L.
Trial statistics
Diseases & Conditions
Objectives
The primary objective of this study is to evaluate the concentration of each allergen extract, specifically **Phleum pratense** and **Dactylis glomerata**, that induces a wheal of size equivalent to that produced by a 10 mg/mL **histamine dihydrochloride** solution. This is clinically relevant as it helps determine the appropriate concentration for skin-prick tests, which are essential in diagnosing allergies to these specific pollen extracts.
The secondary objective is to assess the safety and tolerability of each allergen extract, **Phleum pratense** and **Dactylis glomerata**. Evaluating these parameters is crucial to ensure that the allergen extracts are safe for use in diagnostic procedures and do not cause adverse reactions in patients.
Participants
The clinical trial involves **participants** aged 18 to 64 years, including both **male** and **female** subjects. The study population is characterized by individuals with a positive medical history of inhalant allergy, specifically rhinitis, rhinoconjunctivitis, or asthma, to **Phleum pratense** and **Dactylis glomerata**. Participants must reside in geographical areas where allergic reactions to these allergens are prevalent. The trial does not include a vulnerable population. The sponsor has not provided the total number of participants. Key lifestyle considerations include the requirement for women of childbearing age to use highly effective contraception methods during the trial and up to 72 hours after the end of treatment. The selection criteria emphasize a positive prick-test with allergen extracts and specific IgE presence, ensuring the inclusion of individuals with a confirmed allergic response. The trial excludes individuals with a wheal area obtained with a negative control of 7 mm² or more, corresponding to a mean wheal diameter of 3 mm or more.
Plans and Procedures
The clinical trial is designed to evaluate the concentration of allergen extracts from **Phleum pratense** and **Dactylis glomerata** that produce a wheal size equivalent to that induced by a 10 mg/mL **histamine dihydrochloride** solution. This is a Phase IV, randomized, double-blind, controlled trial focusing on individuals with a documented allergy to these specific pollen extracts. The trial will commence with a screening visit to confirm eligibility based on inclusion criteria, such as a positive history of inhalant allergy and a positive skin prick test. Participants will be required to provide informed consent and meet specific demographic and health criteria, including age and geographical residence.
The trial will involve multiple study visits, beginning with the initial screening visit, followed by the administration of the skin prick test using the investigational products and controls. The primary endpoint is the measurement of the wheal area induced by each allergen extract concentration, compared to the positive and negative controls. Secondary endpoints include the assessment of adverse events and reactions at the administration site. Follow-up visits will be scheduled to monitor participants for any adverse reactions and to ensure the collection of accurate data regarding the efficacy and safety of the allergen extracts.
The expected duration of participant involvement is approximately six months, with the trial estimated to conclude by April 2025. Participants may be withdrawn from the study if they experience significant adverse reactions, fail to comply with study procedures, or withdraw consent. The trial will adhere to rigorous ethical standards and regulatory requirements to ensure the safety and well-being of all participants. The study's findings will contribute to the understanding of allergen extract efficacy in diagnosing allergies to **Phleum pratense** and **Dactylis glomerata**.
Treatment
The clinical trial involves the use of several **experimental medications** and controls in the form of solutions for skin-prick tests. The first experimental medication is the "Prick test of enriched Phleum pratense pollen extract." This product is a solution specifically formulated for skin-prick testing, containing enriched **Phleum pratense pollen extract** as the active substance. The solution is administered via cutaneous use, with a maximum daily dose of 2 drops and a total dose not exceeding 6 nanoliters over a treatment period of 1 day. The product is manufactured by INMUNOTEK S.L. and is not a pediatric formulation.
The second experimental medication is the "Prick test of enriched Dactylis glomerata pollen extract." Similar to the first, this is a solution for skin-prick testing, containing enriched **Dactylis glomerata pollen extract**. It is also administered cutaneously, with the same dosing schedule as the Phleum pratense extract: a maximum of 2 drops per day and a total of 6 nanoliters over 1 day. This product is also produced by INMUNOTEK S.L. and is not intended for pediatric use.
In addition to the experimental medications, the study employs a positive control known as the "Skin Prick Test Positive control," which contains **histamine dihydrochloride** as the active substance. This solution is used to establish a baseline response in participants and is administered cutaneously. The dosing is limited to 2 drops per day, with a total dose of 2 nanoliters over a 1-day period. This control is also provided by INMUNOTEK S.L.
The study also includes a negative control, the "Skin Prick Test Negative control," which contains **sodium chloride**. This solution serves as a baseline for non-reactive responses in the skin-prick test. It is administered in the same manner as the other solutions, with a maximum of 2 drops per day and a total dose of 2 nanoliters over 1 day. This control is manufactured by INMUNOTEK S.L.
Efficacy
Efficacy in this clinical trial will be assessed by evaluating the primary endpoint, which involves measuring the area (mm²) of the induced wheal on the skin. This is done through a **prick test** using three concentrations of each allergenic extract, specifically **Phleum pratense** and **Dactylis glomerata**, as well as positive and negative controls. The positive control is a 10 mg/mL histamine dihydrochloride solution, and the negative control is a sodium chloride solution. The primary objective is to determine the concentration of each allergen extract that induces a wheal size equivalent to that produced by the histamine solution.
Secondary endpoints include the overall rate, seriousness, and ratio of any adverse events (AEs) by administration and by subject. Additionally, the assessment will cover administration site reactions, systemic reactions, and any medication administered for the treatment of adverse reactions (ARs). These efficacy parameters will be collected and analyzed throughout the trial to ensure comprehensive evaluation of the allergenic extracts' performance in inducing a wheal response comparable to the histamine control.
Inclusion and Exclusion Criteria
Inclusion Criteria
- Subjects who have signed and dated informed consent form
- Female or male aged 18 to 64 years, both included
- Subjects must reside in a geographical area where allergic problems caused by Phleum pratense and Dactylis glomerata are relevant
- Positive medical history of inhalant allergy (rhinitis and/or rhinoconjunctivitis and/or asthma) to Phleum pratense and Dactylis glomerata
- A positive prick-test (mean wheal diameter ≥ 3 mm) with extracts of the same allergens and/or presence of specific IgE against complete extract or any molecular component to the allergenic sources.
- The area of the wheal obtained with 10 mg/mL histamine dihydrochloride should be ≥ 7 mm², which corresponds to a mean wheal diameter ≥ 3 mm.
- The area of the wheal obtained with negative control should be < 7 mm², which corresponds to a mean wheal diameter < 3 mm.
- Women of childbearing age (i.e following menarche and until postmenopause, defined as no menses for 12 months without an alternative medical cause, or non-subject to permanent sterilization methods, such as hysterectomy, bilateral salpingectomy, and bilateral oophorectomy) must present a negative urine pregnancy test at the time of enrollment in the trial, as well as a confirmed menstrual period.
- Women of childbearing age must commit to using a highly effective and adequate contraception method during the trial and up to 72 hours after the end of treatment with the investigational medicinal product. Such methods include combined (estrogen and progestogen containing) hormonal; contraception associated with inhibition of ovulation (oral, intravaginal, or transdermal), progestogen-only hormonal contraception associated with inhibition of ovulation (oral, injectable or implantable), intrauterine device, intrauterine hormone releasing system, male condom, diaphragm used with spermicide, bilateral tubal occlusion, vasectomized partner or sexual abstinence.
Exclusion Criteria
- Subjects outside the age range.
- Subjects who have previously received immunotherapy within the last 5 years for the treatment of asthma or allergic rhinoconjunctivitis induced by allergens that may interfere with the extracts of Phleum pratense and Dactylis glomerata.
- Subjects with significant symptoms of rhinoconjunctivitis and/or bronchial asthma in whom discontinuation of systemic antihistamine treatment is contraindicated.
- Subjects who have previously exhibited a severe adverse reaction during diagnostic skin prick tests.
- Subjects on treatment with ß-blockers.
- Use of drugs that could interfere with skin prick test reactions (e.g., antihistamines)
- Clinically unstable subjects (acute asthma, febrile, etc.).
- Subjects with active urticaria lesions, severe active dermographism, severe atopic dermatitis, sunburn, eczema, psoriasis lesions in the area where the prick test is performed (risk of false positives)
- Subjects with active herpes simplex viral infection, or herpes varicella zoster in the area where the prick test is performed.
- Subjects with any pathology in which the administration of adrenaline is contraindicated (hyperthyroidism, hypertension, heart disease, etc.)
- States in which the subject is unable to offer cooperation and severe psychiatric disorders.
- Pregnant or potentially pregnant women and breastfeeding women.
- Subjects with known phenol allergy.
Trial Status by Country
| Country | Status | Start of Recruitment | Planned Patients |
|---|---|---|---|
 Spain | Not Recruiting | 30 Oct 2024 | 30 |
Sites & Investigators
Research sites
Investigators
Investigational Products
Details about the medicinal products being studied in this clinical trial.
| Product Name | Role in Trial | Formulation | Administration | Max Daily Dose | Treatment Duration | EU MP Number |
|---|---|---|---|---|---|---|
Prick test of enriched Phleum pratense pollen extract | Test | SOLUTION FOR SKIN-PRICK TEST | CUTANEOUS USE | 2 | 1 | PRD11502920 |
Prick test of enriched Dactylis glomerata pollen extract | Test | SOLUTION FOR SKIN-PRICK TEST | CUTANEOUS USE | 2 | 1 | PRD11502999 |
Skin Prick Test Positive control | Other | SOLUTION FOR SKIN-PRICK TEST | CUTANEOUS USE | 2 | 1 | PRD11269985 |
Skin Prick Test Negative control | Other | SOLUTION FOR SKIN-PRICK TEST | CUTANEOUS USE | 2 | 1 | PRD11276451 |