Threshold Concentrations for Ragweed and Birch Pollen in Seasonal Allergic Rhinitis (NCT05346718) | Clinical Trial Compass
CompletedNot Applicable
Threshold Concentrations for Ragweed and Birch Pollen in Seasonal Allergic Rhinitis
Germany18 participantsStarted 2022-09-01
Plain-language summary
The ragweed Ambrosia artemisiifolia is spreading in northern Europe due to climate change. The pollen are considered highly allergenic and might trigger allergy symptoms at much lower concentrations than e.g. grass or birch pollen. This study aims to determine threshold concentrations for ragweed and birch pollen in patients with seasonal allergic rhinitis. Participants will be exposed in an allergen challenge chamber that was technically modified to maintain very low and stable pollen concentrations for several hours. The study design is adaptive, where the pollen concentrations are escalated or de-escalated based on interim analysis of resulting allergic symptoms.
Who can participate
Age range
18 Years – 65 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Able and willing to give written informed consent.
. Male and female subjects, aged 18-65 years. Women will be considered for inclusion if they are:
. Not pregnant, as confirmed by pregnancy test (see flow chart), and not nursing.
. Of non-child bearing potential (i.e. physiologically incapable of becoming pregnant, including any female who is post-menopausal, with documented proof of hysterectomy or tubal ligation, or meets clinical criteria for menopause and has been amenorrhoeic for more than 1 year prior to the screening visit).
. Of childbearing potential and using a highly effective birth control during the entire study as described in section 8.2.
. Body mass index between 18 and 35 kg/m2.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Threshold concentrations for ragweed and birch pollen
Timeframe: Day 1, Day 7, Day 14, Day 21, Day 28 (at least 3 exposure visits, maximum 5 exposure visits)
Trial details
NCT IDNCT05346718
SponsorFraunhofer-Institute of Toxicology and Experimental Medicine
. History of seasonal allergic rhinitis to ragweed (July to September) or birch pollen (March to May).
. Positive skin prick test response (positive wheal diameter reaction of ≥ 3mm) for Ambrosia artemisiifolia or Betula pendula at screening or within 12 months prior to screening visit.
Exclusion criteria
. Any clinically relevant abnormal findings in physical examination, clinical chemistry, hematology, urinalysis, vital signs, lung function or ECG at screening visit , which, in the opinion of the investigator, may either put the subject at risk because of participation in the study or may influence the results of the study, or the subject's ability to participate in the study.
. Past or present disease, which as judged by the investigator, may affect the outcome of this study. These diseases include, but are not limited to, cardiovascular disease, malignancy, hepatic disease, renal disease, hematological disease, neurological disease, endocrine disease or pulmonary disease (including but not confined to chronic bronchitis, emphysema, tuberculosis, bronchiectasis or cystic fibrosis).
. Subjects with concomitant allergies to seasonal aeroallergens (i.e., grass, trees, weeds, rye; defined as IgE ≥ 3.5 kU/L within the last 12 months prior to screening) which are anticipated to be or become active during study participation.
. Subjects with a symptomatic concomitant allergy to an animal dander being exposed during study participation.
. Subjects with a symptomatic house dust mite allergy.
. Symptoms of a respiratory tract infection within 3 days prior to screening. Subjects may be re-screened if they have been asymptomatic for at least 3 days.
. Asthma requiring more than Step 1 medication according to GINA guidelines (Global Initiative for Asthma Management and Prevention, 2021). Asthmatic subjects taking ICS plus long-acting bronchodilator as needed according to Step 1 must to be switched to salbutamol as needed during study participation.
. Intake of prohibited medication (refer to Section 9.2).