A Phase 2a double blind, randomized, parallel arm, placebo-controlled trial to investigate the effects of two dose levels of CIT-013 on disease activity in patients with Hidradenitis Suppurativa (HS)

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Citryll B.V.

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Skin and Connective Tissue Diseases [C17]

Trial duration

13 Jan 2026 → ongoing

Decision date (initial)

2025-10-13

Transition trial

No

Low-intervention

No

Rare-disease indication

No

Vulnerable population

No

Funding sources

Citryll B.V.

External identifiers

EU CT number

2025-521684-12-00

ClinicalTrials.gov

NCT06993233

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Efficacy, Safety

To evaluate the efficacy of CIT-013 in participants with moderate to severe HS

Secondary objectives 5

1. To describe the safety and tolerability of CIT-013 compared to placebo in participants with moderate to severe HS
2. To evaluate the effect of the combined dosing arms and individual dose arms of CIT-013 compared to placebo on disease activity (IHS4, HiSCR) in participants with moderate to severe HS
3. To evaluate the effect of the combined dosing arms and individual dose arms of CIT-013 compared to placebo on change in number of draining tunnels and pain, in participants with moderate to severe HS
4. To evaluate the effect of the combined dosing arms and individual dose arms of CIT-013 compared to placebo on participant health assessment (Change in measures of Quality of Life (QoL)) in participants with moderate to severe HS
5. To characterize the pharmacokinetic profile of CIT-013 in participants with moderate to severe HS

Conditions and MedDRA coding

Hidradenitis Suppurativa

Regulatory references

Scientific advice from competent authorities

Medicines Evaluation Board, Food And Drug Administration, Medicines And Healthcare Products Regulatory Agency, Paul-Ehrlich-Institut

Plan to share IPD

No

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 10

1. The written ICF has been signed and dated by the participant prior to any trial-related activity
2. Male or female participants with HS of more than 6 months duration
3. ≥ 18 years of age at screening visit
4. Hidradenitis suppurativa lesions present in ≥ 2 distinct anatomic areas, one of which is Hurley Stage II or III (according to Hurley classification system)
5. A total abscess and inflammatory nodule (AN) count of ≥ 5 at screening and Day 1 prior to enrollment/randomization
6. Participant must have had an inadequate response to oral antibiotics OR exhibited recurrence after discontinuation to, OR demonstrated intolerance to, OR have a contraindication to oral antibiotics for treatment of their HS
7. Total draining tunnel count less than 20
8. Women of childbearing potential (WOCBP)1 must agree to use a highly effective method of birth control, defined as those which result in a low failure rate (i.e., less than 1% per year) when used consistently and correctly 2, during the trial and 5 weeks after the last dose, and must have a negative serum pregnancy test prior to entry into the trial
9. Fertile males with partners who are WOCBP must agree to use a condom and inform their WOCBP partner that highly effective methods of birth control are recommended to avoid pregnancy, applying for the time period during the trial and 5 weeks after the last dose. Male participants in general must agree to refrain from donating sperm
10. Participant’s body mass index is between 18 and 40 kg/m2 , inclusive

Exclusion criteria 17

1. Any current and/or recurrent clinically significant skin condition in the treatment area other than HS
2. Participant has a known hypersensitivity to any of the inactive ingredients (L-histidine, Histidine-HCl monohydrate, Sucrose, Polysorbate) of the study treatment, or to drugs of similar chemical structure or pharmacological profile
3. Any other multi-system autoimmune disease
4. Significant clinical manifestation of any metabolic, allergic, dermatological, hepatic, renal, hematological, pulmonary, cardiovascular, gastrointestinal, neurological, respiratory, endocrine, or psychiatric disorder, as determined by the investigator (or designee)
5. Participant has any other condition which, in the investigator’s opinion will interfere with trial participation or will affect the safety, efficacy or measurements during the study
6. Pregnant or lactating or planning to get pregnant during the duration of the study
7. Participant has taken an investigational drug within 3 months or 5 half-lives (whichever is longer) prior to the first dose in this study
8. Dependency (as an employee or relative) to the sponsor or investigator
9. Prior treatment with biological and synthetic disease modifying drugs during the 6 weeks before baseline,
10. Prior treatment with any of the following medications before baseline: a. Any other systemic therapy for HS (28 days before baseline) b. Any IV anti-infective therapy (14 days before baseline)
11. History of malignancy with exception of non-melanoma skin cancer that has been excised and cured
12. Any known or suspicion for relevant infectious diseases associated with clinical signs (e.g., hepatitis B, or hepatitis C, or human immunodeficiency virus),
13. Evidence of active tuberculosis (TB) or being at high risk for TB (excluded by negative blood test at screening and - if prescribed by local law - by imaging via X-ray of the thorax which can be taken within 3 months before screening)
14. History of more than one episode of herpes zoster in the 12 months prior to screening or any opportunistic infection in the 12 months prior to screening, excluding localized mucocutaneous candidiasis
15. Receipt of live vaccine or live therapeutic infectious agent within the 4 weeks prior to screening
16. Participant has a history of severe and/or multiple drug-allergies, or non-allergic drug reactions
17. Participants for whom an approved therapy with demonstrated clinical benefit is indicated, available and expected to be tolerated, OR choose to proceed with standard of care treatment options over the IP (after being appropriately informed of the treatment options, risks, and benefits)

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. • Proportion of participants with HiSCR75 in pooled dose groups of CIT 013 (50 mg CIT-013 and 100 mg CIT-013) versus placebo at V11 (D85)

Secondary endpoints 8

1. Incidence and severity of treatment-emergent (serious) adverse events ((S)AE)s
2. Change from baseline to Day 113 as measured by HiSCR50, HiSCR75 and HiSCR90 -
3. Change from baseline to Day 113 as measured by IHS4
4. Number of draining tunnels - change from baseline (V2) to all assessment timepoints (D29 [V5], D43 [V7], D85 [V11], D113 [V12])
5. Change in pain as reported by participant via numerical rating scale (NRS)
6. Change in Quality of Life as assessed by participant by the DLQI
7. Change in Quality of Life as assessed by participant by the Hidradenitis Suppurativa Quality of Life (HiSQoL)
8. Pharmacokinetic (PK) levels throughout the trial, per originally assigned treatment

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Citryll B.V.

Sponsor organisation

Citryll B.V.

Address

Rk Gebouw, Kloosterstraat 9 Kloosterstraat 9

City

Oss

Postcode

5349 AB

Country

Netherlands

Scientific contact point

Organisation

Citryll B.V.

Contact name

Maarten Kraan

Public contact point

Organisation

Citryll B.V.

Contact name

Sjoerd van Gorp

Third parties 6

Locations

4 EU/EEA countries · 21 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 96 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

7 submissions — initial application plus substantial / non-substantial modifications