Ulcerative ColitisPhase 2NCT06127043

A Study of Efficacy and Safety of Rosnilimab in Subjects With Moderate to Severe Ulcerative Colitis (ROSETTA)

A Phase 2 study testing Rosnilimab in people with Ulcerative Colitis, run by AnaptysBio, Inc. at 100 sites in 15 countries.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record

Search all trials

Trial summary

ROSETTA STUDY: This study will evaluate the safety, tolerability, and efficacy of Rosnilimab in subjects with moderate to severe ulcerative colitis (UC) Read more about this study

Who is it for?: Ages 18 years and older
Conditions the study is for: Ulcerative Colitis
What is being tested?: Rosnilimab
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 132 participants
Where: 100 sitesin 15 countries
Study dates: 4 Dec 2023to May 2026
Phase: Phase 2
Are there results?: Not yet: the study is under way

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 years and older
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Male or female ≥18
Participants with a clinical diagnosis of UC for prior to Day 1
Subject has moderate to severe, active UC, defined as a mMS ≥ 5 with an endoscopy subscore ≥2
Subject has had a surveillance colonoscopy that did not detect potential dysplasia or colon cancer performed within 1 year of Day 1.
Subject has a history of an inadequate response, loss of response, or intolerance to any combination of at least 2 UC therapy classes defined as, but not limited to, aminosalicylates, corticosteroids, immunomodulators, calcineurin inhibitors, or advanced UC therapies (e.g., biologics, JAK inhibitors, oral S1P receptor modulators, etc.)

Who cannot join

Subject has a diagnosis of Crohn's disease or indeterminate colitis.
Subject has a diagnosis of fulminant colitis and/or toxic megacolon.
Subject has a history of an inadequate response, loss of response, or intolerance to any combination of 3 or more advanced UC therapy classes but not limited to, 1) anti-TNF antibodies (e.g., adalimumab, golimumab, infliximab), 2) other biologics (e.g., ustekinumab, vedolizumab), 3) oral JAK inhibitors (e.g., tofacitinib, upadacitinib), and 4) oral S1P receptor modulators (e.g., ozanimod).
Subject has disease limited to the rectum (ulcerative proctitis)
Subject has a history of colectomy (total or subtotal), ileoanal pouch, Kock pouch, or ileostomy or is planning bowel surgery.
The subject had prior exposure to a PD-1 or PD-L1 agonist, antagonist, or modulator.

Trial locations and contacts

100 sites in 15 countries.

Country

City, postcode or hospital

100 sites in 15 countries

United States25 sites

AnaptysBio Investigational Site 10-122
Atlanta, Georgia, 30328
AnaptysBio Investigational Site 10-127
Brooksville, Florida, 34601
AnaptysBio Investigational Site 10-136
Cincinnati, Ohio, 45201
AnaptysBio Investigational Site 10-104
Dallas, Texas, 75246
AnaptysBio Investigational Site 10-117
Garden Grove, California, 92845
AnaptysBio Investigational Site 10-113
Garland, Texas, 75044
AnaptysBio Investigational Site 10-135
Georgetown, Texas, 78626
AnaptysBio Investigational Site 10-103
Kingsport, Tennessee, 37663
AnaptysBio Investigational Site 10-112
Lancaster, California, 93534
AnaptysBio Investigational Site 10-129
Lancaster, California, 93534
AnaptysBio Investigational Site 10-118
Las Vegas, Nevada, 89128
AnaptysBio Investigational Site 10-134
Lubbock, Texas, 79382
AnaptysBio Investigational Site 10-106
Miami, Florida, 33165
AnaptysBio Investigational Site 10-109
Miami Gardens, Florida, 33014
AnaptysBio Investigational Site 10-120
Norman, Oklahoma, 73017
AnaptysBio Investigational Site 10-124
Oak Lawn, Illinois, 60453
AnaptysBio Investigational Site 10-131
Orlando, Florida, 32789
AnaptysBio Investigational Site 10-123
Orlando, Florida, 32822
AnaptysBio Investigational Site 10-115
Phoenix, Arizona, 85018
AnaptysBio Investigational Site 10-108
San Jose, California, 95124
AnaptysBio Investigational Site 10-107
Seattle, Washington, 98195
AnaptysBio Investigational Site 10-130
Southlake, Texas, 76092
AnaptysBio Investigational Site 10-125
Tampa, Florida, 33607
AnaptysBio Investigational Site 10-132
Tyler, Texas, 75701
AnaptysBio Investigational Site 10-133
Utica, New York, 13501

Other trials in United States

Poland19 sites

AnaptysBio Investigational Site 30-108
Bydgoszcz
AnaptysBio Investigational Site 30-106
Częstochowa
AnaptysBio Investigational Site 30-112
Elblag
AnaptysBio Investigational Site 30-102
Katowice
AnaptysBio Investigational Site 30-115
Katowice
AnaptysBio Investigational Site 30-111
Krakow
AnaptysBio Investigational Site 30-123
Krakow
AnaptysBio Investigational Site 30-103
Lodz
AnaptysBio Investigational Site 30-119
Lodz
AnaptysBio Investigational Site 30-114
Lublin
AnaptysBio Investigational Site 30-104
Poznan
AnaptysBio Investigational Site 30-117
Poznan
AnaptysBio Investigational Site 30-120
Poznan
AnaptysBio Investigational Site 30-116
Rzeszów
AnaptysBio Investigational Site 30-113
Sopot
AnaptysBio Investigational Site 30-110
Torun
AnaptysBio Investigational Site 30-101
Warsaw
AnaptysBio Investigational Site 30-107
Warsaw
AnaptysBio Investigational Site 30-109
Warsaw

Other trials in Poland

Italy11 sites

AnaptysBio Investigational Site 20-112
Bologna
AnaptysBio Investigational Site 20-111
Cagliari
AnaptysBio Investigational Site 20-110
Catania
AnaptysBio Investigational Site 20-108
Legnano
AnaptysBio Investigational Site 20-105
Milan
AnaptysBio Investigational Site 20-107
Pavia
AnaptysBio Investigational Site 20-102
Rozzano
AnaptysBio Investigational Site 20-109
San Donato
AnaptysBio Investigational Site 20-104
San Giovanni
AnaptysBio Investigational Site 20-113
Turin
AnaptysBio Investigational Site 20-106
Udine

Other trials in Italy

Germany8 sites

AnaptysBio Investigational Site 17-107
Berlin
AnaptysBio Investigational Site 17-106
Brandenburg
AnaptysBio Investigational Site 17-105
Dachau
AnaptysBio Investigational Site 17-101
Duisburg
AnaptysBio Investigational Site 17-110
Erlangen
AnaptysBio Investigational Site 17-108
Hamburg
AnaptysBio Investigational Site 17-103
Kiel
AnaptysBio Investigational Site 17-109
Ulm

Other trials in Germany

United Kingdom7 sites

AnaptysBio Investigational Site 27-103
Belfast
AnaptysBio Investigational Site 27-102
Cambridge
AnaptysBio Investigational Site 27-106
Liverpool
AnaptysBio Investigational Site 27-101
London
AnaptysBio Investigational Site 27-105
Runcorn
AnaptysBio Investigational Site 27-107
Shrewsbury
AnaptysBio Investigational Site 27-104
York

Other trials in United Kingdom

Georgia6 sites

AnaptysBio Investigational Site 59-101
Tbilisi, Georgia, 0160
AnaptysBio Investigational Site 59-106
Tbilisi, 0101
AnaptysBio Investigational Site 59-103
Tbilisi, 0102
AnaptysBio Investigational Site 59-102
Tbilisi, 0141
AnaptysBio Investigational Site 59-104
Tbilisi, 0160
AnaptysBio Investigational Site 59-105
Tbilisi, 0180

Other trials in Georgia

Serbia5 sites

AnaptysBio Investigational Site 58-101
Belgrade
AnaptysBio Investigational Site 58-103
Belgrade
AnaptysBio Investigational Site 58-104
Belgrade
AnaptysBio Investigational Site 58-105
Belgrade
AnaptysBio Investigational Site 58-102
Zrenjanin

Other trials in Serbia

Austria4 sites

AnaptysBio Investigational Site 12-101
Innsbruck
AnaptysBio Investigational Site 12-104
Salzburg
AnaptysBio Investigational Site 12-103
Sankt Pölten
AnaptysBio Investigational Site 12-102
Vienna

Other trials in Austria

Canada3 sites

AnaptysBio Investigational Site 11-105
Calgary
AnaptysBio Investigational Site 11-102
London, Ontario
AnaptysBio Investigational Site 11-103
Montreal, Quebec

Other trials in Canada

France3 sites

AnaptysBio Investigational Site 16-102
Nantes
AnaptysBio Investigational Site 16-103
Nantes
AnaptysBio Investigational Site 16-101
Tours

Other trials in France

Romania3 sites

AnaptysBio Investigational Site 30-101
Bucharest
AnaptysBio Investigational Site 31-103
Cluj-Napoca
AnaptysBio Investigational Site 31-102
Timișoara

Other trials in Romania

Croatia2 sites

AnaptysBio Investigational Site 74-104
Rijeka
AnaptysBio Investigational Site 74-101
Zagreb

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Spain2 sites

AnaptysBio Investigational Site 24-102
Alicante
AnaptysBio Investigational Site 24-103
Lleida

Other trials in Spain

Bulgaria1 site

AnaptysBio Investigational Site 61-102
Sofia

Other trials in Bulgaria

Netherlands1 site

AnaptysBio Investigational Site 21-101
Amsterdam

Other trials in Netherlands

About this study

Official title: A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Rosnilimab in Subjects With Moderate to Severe Ulcerative Colitis

ROSETTA STUDY: This study will evaluate the safety, tolerability, and efficacy of Rosnilimab in subjects with moderate to severe ulcerative colitis (UC)

Read the detailed description

This is a Phase 2, randomized, double-blind, placebo-controlled, parallel-group, multicenter study to evaluate the efficacy, safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity of rosnilimab in subjects with moderate to severe ulcerative colitis (UC).

Conditions: Ulcerative Colitis
Being tested: Rosnilimab, Placebo
Keywords: Rosnilimab, ANB030, PD-1 agonist, ROSETTA
Medical subject headings: Colitis, Ulcerative

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

RosnilimabDrug
Also called ANB030
PD-1 agonist antibody
PlaceboDrug
Administered via SC

Study groups in NCT06127043
Study group	Role	What they receive
Rosnilimab SC Dose 1	Experimental	This arm will receive High dose Rosnilimab SC Receives: Drug: Rosnilimab
Rosnilimab SC Dose 2	Experimental	This arm will receive low dose Rosnilimab SC Receives: Drug: Rosnilimab
Placebo	Placebo comparator	This arm will receive Placebo SC Receives: Drug: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

Mean change in modified Mayo Score (mMs) from Baseline to Week 12
The mMS is an endoscopic and clinical scale, which ranges in scores from 0-9, with higher numbers indicating increased disease severity. It is used to assess UC disease activity. It consists of three subscores: RBS, SFS and an endoscopy subscore.
Measured: Baseline to Week 12

Secondary outcomes (3)

Proportion of subjects achieving clinical remission at Week 12
Defined as a mMS ≤ 2, with a stool frequency subscore (SFS) ≤ 1, RBS=0, and endoscopic subscore ≤ 1 without friability.
Measured: Baseline to Week 12
Proportion of subjects showing endoscopic treatment improvement at Week 12
Defined as an endoscopy subscore ≤ 1 without friability.
Measured: Baseline to Week 12
Proportion of subjects achieving a clinical response at Week 12
Defined as a decrease from Baseline in mMS ≥ 2 points and ≥ 30% with a decrease from Baseline in RBS ≥ 1 point or an absolute RBS ≤ 1.
Measured: Baseline to Week 12

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

4 Dec 2023May 2026

First posted13 Nov 2023
Study start4 Dec 2023
Primary completionJan 2026 (estimated)
Study completionMay 2026 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for Ulcerative ColitisStudies 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 2
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind
Who is masked: Participant, Care provider, Investigator, Outcomes assessor
Enrolment: 132 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT06127043
Sponsor's protocol ID: ANB030-204 ROSETTA
Status last verified: Sep 2025
First submitted: 7 Nov 2023
Last updated: 3 Oct 2025
Results posted: No
Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: No

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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Longitudinal Immunophenotyping of Patients With Inflammatory Bowel Disease
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Ibd CAncer and seRious Infections in France (I-CARE 2)
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RecruitingObservational study
Characterization of Colorectal Dysplasic Lesions and Stratification of Their Evolving Risk in Inflammatory Bowel Disease Patients: a Prospective, Observational and Multicenter Study
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Enrolling by invitationPhase 4
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All Ulcerative Colitis trials

Study at a glance

From the registry record, last updated by the sponsor on 3 Oct 2025. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Rosnilimab in Subjects With Moderate to Severe Ulcerative Colitis
ClinicalTrials.gov ID: NCT06127043
Acronym / sponsor ID: ANB030-204 ROSETTA
Conditions: Ulcerative Colitis
Keywords: Rosnilimab, ANB030, PD-1 agonist, ROSETTA
Phase: Phase 2
Study type: Interventional
Recruitment status: Active, not recruiting
Enrolment: 132 participants (estimated)
Lead sponsor: AnaptysBio, Inc.Industry (pharma, biotech, devices)
Study start: 4 Dec 2023 (actual)
Primary completion: Jan 2026 (estimated)
Study completion: May 2026 (estimated)
First posted: 13 Nov 2023 (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.

ROSETTA STUDY: This study will evaluate the safety, tolerability, and efficacy of Rosnilimab in subjects with moderate to severe ulcerative colitis (UC)

Detailed description

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Parallel groups
Masking: Quadruple blind (participant, care provider, investigator, outcomes assessor)
Number of arms: 3

Arm	Type	Receives
Rosnilimab SC Dose 1	Experimental	Drug: RosnilimabThis arm will receive High dose Rosnilimab SC
Rosnilimab SC Dose 2	Experimental	Drug: RosnilimabThis arm will receive low dose Rosnilimab SC
Placebo	Placebo comparator	Drug: PlaceboThis arm will receive Placebo SC

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (5 listed)

Male or female ≥18
Participants with a clinical diagnosis of UC for prior to Day 1
Subject has moderate to severe, active UC, defined as a mMS ≥ 5 with an endoscopy subscore ≥2
Subject has had a surveillance colonoscopy that did not detect potential dysplasia or colon cancer performed within 1 year of Day 1.
Subject has a history of an inadequate response, loss of response, or intolerance to any combination of at least 2 UC therapy classes defined as, but not limited to, aminosalicylates, corticosteroids, immunomodulators, calcineurin inhibitors, or advanced UC therapies (e.g., biologics, JAK inhibitors, oral S1P receptor modulators, etc.)

Key exclusion criteria (6 listed)

Subject has a diagnosis of Crohn's disease or indeterminate colitis.
Subject has a diagnosis of fulminant colitis and/or toxic megacolon.
Subject has a history of an inadequate response, loss of response, or intolerance to any combination of 3 or more advanced UC therapy classes but not limited to, 1) anti-TNF antibodies (e.g., adalimumab, golimumab, infliximab), 2) other biologics (e.g., ustekinumab, vedolizumab), 3) oral JAK inhibitors (e.g., tofacitinib, upadacitinib), and 4) oral S1P receptor modulators (e.g., ozanimod).
Subject has disease limited to the rectum (ulcerative proctitis)
Subject has a history of colectomy (total or subtotal), ileoanal pouch, Kock pouch, or ileostomy or is planning bowel surgery.

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
RosnilimabAlso: ANB030PD-1 agonist antibody	Drug	Rosnilimab SC Dose 1, Rosnilimab SC Dose 2
PlaceboAdministered via SC	Drug	Placebo

Primary outcome

Mean change in modified Mayo Score (mMs) from Baseline to Week 12
Time frame: Baseline to Week 12
The mMS is an endoscopic and clinical scale, which ranges in scores from 0-9, with higher numbers indicating increased disease severity. It is used to assess UC disease activity. It consists of three subscores: RBS, SFS and an endoscopy subscore.

3 secondary outcomes

Proportion of subjects achieving clinical remission at Week 12
Time frame: Baseline to Week 12
Proportion of subjects showing endoscopic treatment improvement at Week 12
Time frame: Baseline to Week 12
Proportion of subjects achieving a clinical response at Week 12
Time frame: Baseline to Week 12

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 3 Oct 2025.
Individual participant dataSharing planned: No

Related trials for Ulcerative Colitis

Not yet recruitingPhase 1
An Open-label, DDI Study to Investigate the Effects of Duvakitug on the PK of Selected Cytochrome P450 Substrates
Ulcerative Colitis, Crohn's Disease
RecruitingObservational study
Longitudinal Immunophenotyping of Patients With Inflammatory Bowel Disease
Inflammatory Bowel Disease, Crohn's Disease
RecruitingObservational study
Ibd CAncer and seRious Infections in France (I-CARE 2)
IBD, Ulcerative Colitis
RecruitingObservational study
Characterization of Colorectal Dysplasic Lesions and Stratification of Their Evolving Risk in Inflammatory Bowel Disease Patients: a Prospective, Observational and Multicenter Study
Crohn Disease (CD), Colitis Ulcerative
Enrolling by invitationPhase 4
MOdel-Informed Precision Dosing of Ustekinumab and VEdolizumab in Inflammatory Bowel Disease
Inflammatory Bowel Diseases, Crohn Disease

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.

Zurab Machaidze, MD study director

AnaptysBio, Inc.

100 sites in 15 countries: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 2 study testing Rosnilimab in people with Ulcerative Colitis, run by AnaptysBio, Inc. at 100 sites in 15 countries.

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 5 inclusion and 6 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: under way, not looking for participants, as of the sponsor's last update on 3 Oct 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 100 sites in United States, Poland, Italy, Germany, United Kingdom and 10 more countries. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

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?

Mean change in modified Mayo Score (mMs) from Baseline to Week 12 (time frame: Baseline to Week 12). 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 NCT06127043.

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 3 Oct 2025; AzTrials last refreshed its copy on 8 Nov 2026.