RecruitingPHASE2INTERVENTIONAL

A Study With CIT-013 in HS Patients

This study is looking into a new medicine called CIT-013 for adults who have a skin condition called Hidradenitis Suppurativa (HS). HS causes painful lumps and boils. The main goal is to find out if CIT-013 can help make HS symptoms better and if it’s safe to use. This is a ‘Phase 2’ study, which means it’s still in the earlier stages of testing. Participants will either receive a high dose of CIT-013, a medium dose, or a placebo (a 'dummy' medicine with no active drug) every two weeks for 12 weeks. Researchers will closely monitor their health and HS symptoms during this time through regular clinic visits and tests. This helps them understand how well CIT-013 works compared to not having the active drug.

At a glance

Status

Recruiting

Phase

PHASE2

Sponsor

Citryll BV

Enrolment target

Start

31 Oct 2025

Estimated completion

01 Jul 2027

Hidradenitis Suppurativa (HS)

What is this study about?

This clinical trial is exploring a new potential treatment for a skin condition called Hidradenitis Suppurativa (HS). HS is a long-term condition that causes painful lumps, boils, and abscesses, often in areas where skin rubs together, like the armpits or groin. It can be very uncomfortable and affect daily life.

The new medicine being tested is called CIT-013. The main purpose of this study is to see if CIT-013 can help reduce the symptoms of HS, like the number of painful lumps, and to check if it's safe for people to use. This kind of study, known as a Phase 2 trial, is an important step in developing new medicines. It helps researchers get a better understanding of how the medicine works and if it has any side effects.

To figure this out, some participants will receive a dose of CIT-013, while others will receive a 'placebo'. A placebo looks exactly like the real medicine but doesn't contain any active drug. Comparing the group who received CIT-013 with the group who received the placebo helps the researchers understand if any improvements are genuinely due to the medicine or if they might have happened anyway. Participants will be monitored closely for 12 weeks to track their symptoms and overall health.

Key takeaways

This study is testing a new medicine (CIT-013) for adults with HS.
It aims to see if CIT-013 reduces HS symptoms and is safe.
You might receive CIT-013 or a dummy medicine (placebo) for 12 weeks.
You'll have regular clinic visits and health checks over these 12 weeks.
Your HS must have been poorly controlled by or intolerant to oral antibiotics.
Participation is voluntary, and you can withdraw at any time.

Who may be eligible?

To join this study, you need to be an adult (18 years or older) and have Hidradenitis Suppurativa (HS) that has been present for at least six months. Your HS needs to affect at least two different body areas, with at least one area being moderately or severely affected, and you should currently have at least five painful lumps or inflamed spots.

Critically, you should have tried oral antibiotics for your HS in the past, but they either didn't work well enough, your HS came back after stopping them, you couldn't tolerate them, or you couldn't take them for some other medical reason. You also shouldn't have too many 'draining tunnels' – these are channels under the skin that can weep fluid.

There are also some reasons why you might not be able to join. For example, if your doctor believes there's already a suitable and effective HS treatment available for you that you haven't yet tried, or if you have other serious skin conditions in the areas where your HS is. Also, if you've recently used certain other powerful injected medicines or systemic treatments for HS, or some strong antibiotics, you might not be eligible. People with a history of cancer (except for certain skin cancers that have been cured) are also typically not included.

Quick self-check

Are you 18 years old or older?
Have you had HS for at least 6 months?
Does your HS affect at least two body areas, with at least one moderate/severe?
Do you currently have at least five painful HS lumps/inflamed spots?
Did oral antibiotics not work well for your HS, or could you not take them?
Do you have fewer than 20 draining tunnels?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you decide to take part in this study, you'll be involved for about 12 weeks. During this time, you'll visit the clinic once every two weeks for check-ups and to have different tests. These tests might include blood tests, physical examinations, and assessments of your HS symptoms to track any changes.

Every two weeks, you will either receive a dose of CIT-013 (either a high or medium dose) or a placebo. This will likely be given as an injection. Throughout the study, you'll also be asked to keep an eye on your symptoms and likely record them in a diary or on a phone app. The study team will guide you on how to do this. After the 12 weeks, there will be a final check-up to ensure everything is okay.

Potential risks and benefits

Taking part in a clinical trial offers the potential benefit of accessing a new treatment before it's widely available, which might help improve your HS symptoms. You'll also receive careful monitoring and support from a dedicated medical team. However, as with any medicine, CIT-013 might cause side effects, some of which are not yet fully known. There's also a chance that the treatment might not work for you, or that you could receive the placebo. Your participation is completely voluntary, and you have the right to withdraw from the study at any time, for any reason, without affecting your regular medical care.

Locations (28)

CA-01
Barrie, Canada· Recruiting
CA-05
Calgary, Canada· Recruiting
CA-02
London, Canada· Recruiting
CA-04
Newmarket, Canada· Recruiting
CA-03
Winnipeg, Canada· Recruiting
DE-06
Bad Bentheim, Germany· Recruiting
DE-01
Bochum, Germany· Recruiting
DE-04
Dresden, Germany· Recruiting
DE-02
Frankfurt, Germany· Recruiting
DE-08
Kiel, Germany· Recruiting
DE-03
Oldenburg, Germany· Recruiting
Erasmus UMC
Rotterdam, Netherlands· Recruiting

+16 more sites — see the official record for the full list.

Common questions

What is Hidradenitis Suppurativa (HS)?

HS is a long-term skin condition that causes painful lumps, boils, and abscesses, often in body folds like armpits or groin. It can be uncomfortable and affect daily life.

What does 'Phase 2' mean for a clinical trial?

Phase 2 means this is an earlier stage of testing a new medicine. Researchers are trying to find out if it works and what the right dose might be, as well as checking for side effects.

What is a placebo?

A placebo is a 'dummy' medicine that looks like the real treatment but contains no active drug. It helps researchers compare the effects of the active medicine against no treatment.

How long will I be involved in the study?

Your active involvement with clinic visits and medication will last for about 12 weeks.

Can I leave the study if I change my mind?

Yes, you can choose to leave the study at any time, for any reason. Your decision won't affect your future medical care.

How to find out more

Leonie M Middelink

lmiddelink@citryll.com +31613328444 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.