Healthy AdultPhase 1CityskyNCT07499908
Trial in Healthy Volunteers to Evaluate 150 mg Subcutaneous CIT-013
A Phase 1 study testing CIT-013 high dose in people with Healthy Adult, run by Citryll BV at 1 site in Netherlands.
Trial summary
This is a phase 1, double-blind, randomized, placebo-controlled, single center, repeat-dose trial for the assessment of safety, tolerability, bioavailability and pharmacokinetic profiles of 150 mg CIT-013 in healthy adult volunteers Read more about this study
- Who is it for?
- Ages 18 to 75 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Adult
- What is being tested?
- CIT-013 high dose
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 10 participants
- Where
- 1 siteNetherlands
- Study dates
- 23 Jun 2026to 12 Aug 2026
- Phase
- Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy men or women, 18 to 75 years of age (inclusive) at screening.
- Informd Consent
- Body mass index is between 18.0 and 32.0 kg/m2
Who cannot join
- Evidence of any active or chronic disease or condition that could interfere with, or for which the treatment might interfere with, the conduct of the trial, or that would pose an unacceptable risk to the participant in the opinion of the Investigator.
- Any history of severe allergic reaction(s)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Phase 1, Randomized, Double-Blind, Placebo-Controlled, Repeat-Dose Trial to Evaluate 150 mg Subcutaneous CIT-013 Administration in Healthy Adult Volunteers
This is a phase 1, double-blind, randomized, placebo-controlled, single center, repeat-dose trial for the assessment of safety, tolerability, bioavailability and pharmacokinetic profiles of 150 mg CIT-013 in healthy adult volunteers
Read the detailed description
The active treatment in this trial is CIT-013, an investigational medicinal product that will be administered at a fixed dose level of 150 mg, subcutaneous (one 50 mg and one 100 mg injection), and is compared against placebo. CIT-013 is an IgG1k monoclonal antibody consisting of two identical light chain polypeptides composed of 219 amino acids each and two identical heavy chain polypeptides composed of 451 amino acids each. CIT-013 and placebo will be administered via subcutaneous injection in the abdominal wall.
- Conditions
- Healthy Adult
- Being tested
- CIT-013 high dose, Placebo
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CIT-013 high doseDrug
CIT-013
PlaceboDrug
placebo
| Study group | Role | What they receive |
|---|---|---|
| CIT-013 high dose | Experimental | CIT-013 high dose Receives: Drug: CIT-013 high dose |
| Placebo | Placebo comparator | Placebo Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Treatment-Emergent Adverse Events
Frequency and severity of treatment-emergent adverse events (TEAE) throughout the trial period, including clinically relevant findings, and antidrug antibody (ADA) results.
Measured: 6 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Mar 2026
- Study start23 Jun 2026
- Primary completion10 Aug 2026
- Study completion12 Aug 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Healthy AdultStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 10 participants (actual)
Sponsor and investigators
- Lead sponsor
- Citryll BV
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Maarten Kraan, Study director, Citryll BV
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07499908
- Sponsor's protocol ID
- CITRYLL006
- Other IDs
- 2026-526153-34-00
- Acronym
- Citysky
- Status last verified
- Mar 2026
- First submitted
- 24 Mar 2026
- Last updated
- 21 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
https://doi.org/10.1080/19420862.2023.2281763
Study at a glance
From the registry record, last updated by the sponsor on 21 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1, Randomized, Double-Blind, Placebo-Controlled, Repeat-Dose Trial to Evaluate 150 mg Subcutaneous CIT-013 Administration in Healthy Adult Volunteers
- ClinicalTrials.gov ID
- NCT07499908
- Acronym / sponsor ID
- Citysky / CITRYLL006
- Conditions
- Healthy Adult
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 10 participants (actual)
- Lead sponsor
- Citryll BVIndustry (pharma, biotech, devices)
- Study start
- 23 Jun 2026 (actual)
- Primary completion
- 10 Aug 2026 (actual)
- Study completion
- 12 Aug 2026 (actual)
- First posted
- 30 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a phase 1, double-blind, randomized, placebo-controlled, single center, repeat-dose trial for the assessment of safety, tolerability, bioavailability and pharmacokinetic profiles of 150 mg CIT-013 in healthy adult volunteers
Detailed description
The active treatment in this trial is CIT-013, an investigational medicinal product that will be administered at a fixed dose level of 150 mg, subcutaneous (one 50 mg and one 100 mg injection), and is compared against placebo. CIT-013 is an IgG1k monoclonal antibody consisting of two identical light chain polypeptides composed of 219 amino acids each and two identical heavy chain polypeptides composed of 451 amino acids each. CIT-013 and placebo will be administered via subcutaneous injection in the abdominal wall.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| CIT-013 high dose | Experimental | Drug: CIT-013 high doseCIT-013 high dose |
| Placebo | Placebo comparator | Drug: PlaceboPlacebo |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Healthy men or women, 18 to 75 years of age (inclusive) at screening.
- Informd Consent
- Body mass index is between 18.0 and 32.0 kg/m2
Key exclusion criteria (2 listed)
- Evidence of any active or chronic disease or condition that could interfere with, or for which the treatment might interfere with, the conduct of the trial, or that would pose an unacceptable risk to the participant in the opinion of the Investigator.
- Any history of severe allergic reaction(s)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CIT-013 high doseCIT-013 | Drug | CIT-013 high dose |
| Placeboplacebo | Drug | Placebo |
Primary outcome
Incidence of Treatment-Emergent Adverse Events
Time frame: 6 weeks
Frequency and severity of treatment-emergent adverse events (TEAE) throughout the trial period, including clinically relevant findings, and antidrug antibody (ADA) results.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Oct 2026.
- Results publicationhttps://doi.org/10.1080/19420862.2023.2281763
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Maarten Kraan study director
Citryll BV
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing CIT-013 high dose in people with Healthy Adult, run by Citryll BV at 1 site in Netherlands.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 21 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Netherlands. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Treatment-Emergent Adverse Events (time frame: 6 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07499908, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Oct 2026.