AuthorisedTherapeutic confirmatory (Phase III)Interventional

A multicenter, double-blind, placebo-controlled, clinical trial to evaluate the efficacy and safety of two concentrations of a mixture of depigmented polymerized allergenic extracts of D. pteronyssinus and D. farinae, in patients suffering from allergic rhinoconjunctivitis with or without controlled asthma

This research study is investigating new treatments for people who suffer from allergies to dust mites, specifically those causing hay fever-like symptoms (allergic rhinitis and conjunctivitis), sometimes with well-controlled asthma. We will be testing two different strengths of a special treatment involving small doses of dust mite extracts. The main goal is to find out if these treatments can reduce your allergy symptoms compared to a dummy treatment (placebo). We'll also check if the treatments are safe. Participants will track their symptoms using a mobile phone app.

At a glance

Status

Authorised

Phase

Therapeutic confirmatory (Phase III)

Sponsor

LETI Pharma S.L.U.

Enrolment target

360

Start

29 Oct 2025

Allergic rhinoconjunctivitis to Dermatophagoides pteronyssinus and Dermatophagoides farinae

What is this study about?

This study is designed to help people who have allergies to common household dust mites, called *Dermatophagoides pteronyssinus* and *Dermatophagoides farinae*. If you're allergic to these mites, you might experience symptoms like a runny or stuffy nose, sneezing, itchy eyes, and watery eyes, which doctors call allergic rhinoconjunctivitis. Some people in the study might also have asthma that is currently well-managed.

We are testing two different treatment strengths that contain small, carefully measured amounts of these dust mite extracts. The idea behind these types of treatments is to help your body get used to the allergens so it reacts less strongly over time. We want to see if either of these treatments can effectively reduce your allergy symptoms and improve your quality of life, compared to taking a placebo, which is a treatment that looks the same but contains no active medicine. We also need to make sure these treatments are safe for people to use.

This is a 'Phase III' study, which means it's a very important step where we confirm if a new treatment works and is safe before it can be made widely available. Your participation will help us understand if these specific dust mite treatments could offer a better way to manage these common allergies for many more people.

Key takeaways

This study is for adults with dust mite allergies affecting their nose and eyes, possibly with asthma.
It tests two strengths of a dust mite allergy treatment against a dummy treatment (placebo).
Symptoms and medication use will be tracked electronically via a mobile app.
Participation helps scientists understand better ways to treat dust mite allergies.
The study involves injections of the treatment and follow-up over several years.

Who may be eligible?

To be part of this study, you need to be an adult, 18 years old or older. Both men and women are welcome to take part.

Critically, you must have been diagnosed with allergies to *Dermatophagoides pteronyssinus* and *Dermatophagoides farinae* dust mites, which cause symptoms like a runny nose, sneezing, and itchy, watery eyes (allergic rhinoconjunctivitis). You might also be considered if you have asthma that is currently well-controlled by your existing medication.

There will be other specific medical criteria that the study doctors will review to ensure this study is suitable and safe for you. They will discuss these in detail to determine if you are a good fit for the research.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Have you been diagnosed with allergies to dust mites (*D. pteronyssinus* and *D. farinae*)?
Do you get hay fever-like symptoms (runny nose, sneezing, itchy/watery eyes) from your dust mite allergy?
If you have asthma, is it currently well-controlled with your existing medicine?

Answer every question to see your result.

What does participation involve?

If you join this study, your journey will involve several visits to the clinic over a period of time. You will receive one of the study treatments, which include different strengths of the dust mite mixture or a placebo, given by injection (SCIT). You might also be given other standard allergy or asthma medications to help manage any symptoms, such as nasal sprays for your nose, eye drops for your eyes, or inhalers for any breathing issues. You will be assigned to a treatment group randomly, meaning neither you nor the doctors will know if you're receiving the active treatment or the placebo until the study ends.

You will need to keep a daily record of your allergy symptoms and any medications you use. This will be done using a special app on your mobile phone, starting from when you first receive treatment. This tracking will continue throughout the treatment period and during follow-up visits, which will extend for one to two years after you've finished your main course of treatment. The study team will explain everything in detail, including how often you'll need to visit and for how long.

Potential risks and benefits

Taking part in this study may offer personal benefits, such as potentially reducing your allergy symptoms and improving your quality of life. Even if you receive the placebo, your participation helps advance medical knowledge that could benefit others. However, as with any medical study, there are potential risks, including discomfort or reactions at the injection site, or possibly side effects from the study medication or other prescribed treatments. All known risks will be clearly explained by the study team. Remember, your participation is completely voluntary, and you are free to withdraw from the study at any time without affecting your usual medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Spain

Common questions

What are dust mites and why do they cause allergies?

Dust mites are tiny insects that live in house dust. Their droppings and body parts can cause allergic reactions in some people, leading to symptoms like sneezing, runny nose, and itchy eyes.

What does 'allergic rhinoconjunctivitis' mean?

It's the medical term for allergy symptoms that affect your nose (rhinitis, like sneezing and a runny nose) and your eyes (conjunctivitis, like itchy, watery eyes).

What is a 'placebo' in a study?

A placebo is a dummy treatment that looks just like the real medicine but contains no active ingredients. It helps researchers compare how well the actual treatment works.

Will I know if I'm getting the real medicine?

No, this is a 'double-blind' study, meaning neither you nor the doctors will know if you're receiving the active treatment or a placebo. This helps ensure fair results.

How will my symptoms be tracked?

You will use a special app on your mobile phone to record your allergy symptoms and any other medications you take, starting from your first treatment.