Colitis Ulcerative · Ulcerative Colitis
MK-8690 for Adults With Moderately to Severely Active Ulcerative Colitis
This study is investigating whether injected MK-8690 improves clinical remission at Week 12 compared with placebo in adults with moderately to severely active ulcerative colitis.
Registry title: A Study to Evaluate Efficacy and Safety of MK-8690 in Participants With Moderately to Severely Active Ulcerative Colitis (MK-8690-002)
10 recruiting U.S. sites ↓Study at a glance
- Age
- 18 Years–75 Years
- Treatment
- MK-8690 or Placebo
- Design
- Randomized · Triple
- Central study contact
- Toll Free Number1-888-577-8839Trialsites@msd.com
- Sponsor
- Merck Sharp & Dohme LLC
Research question
At Week 12, does MK-8690 lead to a greater proportion of participants achieving clinical remission by the Modified Mayo Score than placebo?
Participant snapshot
Who the study is looking for
- The study is looking for adults ages 18 through 75.
- The study is looking for people who have had ulcerative colitis symptoms for at least 3 months and currently have moderately to severely active disease.
- Participants must weigh at least 40 kilograms, or about 88 pounds.
- Participants must have had an inadequate response, loss of response, corticosteroid dependence, or intolerance involving at least one protocol-specified ulcerative colitis treatment.
- Recruiting sites are listed in the United States, Colombia, France, Greece, the Netherlands, Poland, South Korea, and the United Kingdom.
Participation overview
What participation may involve
Participants receive MK-8690 or placebo by injection under the skin during the first 12 weeks. Subsequent MK-8690 treatment depends on whether they respond during Period 1 or Period 2. What participation may involve: - Receive MK-8690 or placebo by injection under the skin for 12 weeks in Period 1. - Participants who do not respond in Period 1 receive MK-8690 by injection under the skin for 12 weeks in Period 2. - Participants who respond in Period 1 or Period 2 receive additional MK-8690 for up to approximately 42 weeks in Period 3. - The study evaluates ulcerative colitis activity using stool frequency, rectal bleeding, and endoscopic findings, and also assesses tissue inflammation. - The study records adverse events and discontinuations caused by adverse events for up to approximately 12 months. Period 1 lasts 12 weeks. Depending on response, participation may include another 12-week treatment period and then up to approximately 42 additional weeks of MK-8690.
Study interventions
What participants may receive or do
- MK-8690: MK-8690, also called PRA052, is given as a solution by injection under the skin. It is used in Period 1 and may also be given in Periods 2 and 3, depending on response.
- Placebo: The placebo is a solution given by injection under the skin during the 12-week first period.
Study design
How the comparison works
This is a Phase 2 interventional treatment study. Period 1 compares MK-8690 with placebo; later open-label periods provide MK-8690 to participants based on their response in earlier periods. The registry describes randomized, parallel assignment and specifically states that Period 1 uses parallel assignment. The structured masking field says participants, investigators, and outcome assessors are masked, while the description calls Period 1 double-blind. Periods 2 and 3 are open-label. The control group receives placebo by injection under the skin for 12 weeks during Period 1. Placebo is used only in Period 1 according to the listed study arms; participants who do not respond in Period 1 receive open-label MK-8690 in Period 2.
Reported activities
Procedures and tests
- MK-8690 or placebo is administered by injection under the skin.
- Stool frequency and rectal bleeding are assessed as parts of the Modified Mayo Score.
- Endoscopy findings are scored to assess disease activity, clinical remission, and endoscopic improvement.
- Tissue inflammation is graded with the Geboes histology score as part of the histologic-endoscopic mucosal improvement assessment.
- Adverse events, including unfavorable symptoms, diseases, signs, or abnormal laboratory findings, are monitored.
- Screening may involve confirming that ulcerative colitis is not limited to the rectum and that excluded forms of colitis are not present.
- Screening may involve checking for active infection, hepatitis B, hepatitis C, human immunodeficiency virus, and tuberculosis exclusion criteria.
Eligibility highlights
Details that may affect whether you contact the study
These are selected highlights, not a complete eligibility check. Exact criteria remain in the full registry record below.
Common requirements
- Ulcerative colitis symptoms must have begun at least 3 months before randomization.
- Ulcerative colitis must currently be moderately to severely active.
- Participants must weigh at least 40 kilograms.
- At least one treatment-history condition must apply: inadequate response or loss of response to a protocol-specified treatment, protocol-specified corticosteroid dependence, or intolerance to a protocol-specified ulcerative colitis treatment.
- Any protocol-specified drugs continued during the study must meet the applicable stabilization requirements.
- The registry age range is 18 through 75 years.
Possible reasons someone may not be able to join
- People with Crohn's disease, indeterminate colitis, inflammatory bowel disease–undefined, or another form of colitis or enteritis that could interfere with assessment are excluded.
- A current diagnosis of fulminant colitis or toxic megacolon is exclusionary.
- Ulcerative colitis limited to the rectum is excluded.
- A current or impending need for a colostomy or ileostomy is exclusionary.
- People who have had a total proctocolectomy or partial colectomy are excluded.
- An ulcerative colitis flare requiring hospitalization within 2 weeks before screening is exclusionary.
- Protocol-specified active infections are exclusionary.
- Known hepatitis B, hepatitis C, or human immunodeficiency virus infection is exclusionary.
- Evidence of active tuberculosis or meeting the protocol's tuberculosis exclusion parameters is exclusionary.
- Most cancer histories require at least 5 years disease-free before randomization; fully treated nonmelanoma skin cancers and surgically removed cervical carcinoma in situ are exceptions, while any colorectal cancer history is exclusionary.
- Definite colonic dysplasia is exclusionary unless it was low-grade dysplasia that was completely removed.
- Major surgery within 3 months before screening, or planned major surgery requiring general anesthesia during the study, is exclusionary.
Important unknowns
What the record does not make clear
- The record does not state how many in-person visits are required or how often they occur.
- The record gives durations for individual treatment periods but does not clearly state each participant's total time in screening, treatment, and follow-up.
- The record lists MK-8690 and placebo groups in Period 1 but does not report the chance of assignment to each group.
- The eligibility criteria refer to protocol-specified drugs and stabilization requirements but do not name the permitted treatments or required stable-treatment periods.
- The record excludes protocol-specified prohibited medications but does not identify them or state any washout periods.
- The record does not describe rescue treatment for worsening ulcerative colitis during the study.
- Endoscopic outcomes are reported for Week 12, but the complete number and timing of required endoscopies are not stated.
- The record does not state which study-related or routine-care costs are covered or billed to insurance.
- The record does not state whether participants are compensated.
- The record does not describe reimbursement or support for transportation, lodging, or meals.
- The record does not state whether any visits or assessments can be completed remotely or locally.
- The record does not describe whether MK-8690 may be available after study participation ends.
Before contacting the site
Questions for the study team
- How many visits, injections, endoscopies, biopsies, laboratory tests, and other assessments are required in each period?
- What is the chance of receiving placebo during Period 1?
- How is response determined at the end of Periods 1 and 2, and how does that result affect the next treatment period?
- Which current ulcerative colitis medications may continue, which must stop, and what stabilization or washout periods apply?
- What happens if ulcerative colitis worsens or urgent treatment becomes necessary during the study?
- What is the expected total participation time, including screening, treatment, and follow-up, for each possible treatment pathway?
- Which study-related costs are covered, and are compensation or travel support available?
- Is the site I am considering currently enrolling, and can any visits or tests be completed locally or remotely?
Before changing care
Questions for your gastroenterologist
- How stable is my ulcerative colitis now, and what risks could arise if my current treatment changes for screening or study participation?
- Which of my previous treatments count as an inadequate response, loss of response, corticosteroid dependence, or intolerance under this protocol?
- What approved treatment alternatives should I consider while evaluating this study?
- Do my disease extent, surgical history, infection history, dysplasia findings, or other medical conditions raise concerns about the study procedures or treatment?
- How should my gastroenterology team and the research team coordinate routine care, flare management, endoscopy results, and medication decisions?
This plain-language digest is provided by the Aidy clinical trials API. It may omit details and is not medical advice or an eligibility decision. Review the full registry record and confirm details with the study team.
Source record
Full registry record
The sections below preserve the study information supplied through ClinicalTrials.gov, including complete descriptions, criteria, outcomes, and locations.
About this study
The purpose of this protocol is to evaluate the efficacy of MK-8690 in participants with moderately to severely active ulcerative colitis. The primary hypothesis is that MK-8690 is superior to placebo with respect to the proportion of participants achieving clinical remission per Modified Mayo Score at Week 12.
Study design and administration
- Organization
- Merck Sharp & Dohme LLC
- Organization class
- Industry
- Organization study ID
- 8690-002
- Lead sponsor
- Merck Sharp & Dohme LLC
- Sponsor class
- Industry
- Enrollment type
- Estimated
- Allocation
- Randomized
- Intervention model
- Parallel
- Primary purpose
- Treatment
- Masking
- Triple
- Who is masked
- Participant, Investigator, Outcomes Assessor
- Standard age groups
- Adult, Older Adult
Study arms
Experimental
Period 1: MK-8690
Participants will receive MK-8690 via subcutaneous injection for 12 weeks.
Interventions: Drug: MK-8690
Placebo Comparator
Period 1: Placebo
Participants will receive placebo via subcutaneous injection for 12 weeks.
Interventions: Other: Placebo
Experimental
Period 2: MK-8690
Participants who do not respond to treatment in Period 1 (regardless of treatment assignment in Period 1) will receive MK-8690 via subcutaneous injection for 12 weeks.
Interventions: Drug: MK-8690
Experimental
Period 3: MK-8690
Participants who respond to treatment in either Period 1 or Period 2 will receive additional MK-8690 via subcutaneous injection for up to approximately 42 weeks.
Interventions: Drug: MK-8690
Interventions
Drug
MK-8690
Solution for subcutaneous injection
Other
Placebo
Solution for subcutaneous injection
Eligibility
18 Years–75 Years
All
Not accepted
Inclusion criteria (5)
- Has had ulcerative colitis (UC) (from onset of symptoms) for at least 3 months before RandomizationRegistry-derived · unreviewed
- Has moderately to severely active UCRegistry-derived · unreviewed
- Has a weight ≥40 kgRegistry-derived · unreviewed
- Satisfies at least 1 of the criteria: Has had an inadequate response or loss of response to 1 or more protocol-specified treatments; protocol specified corticosteroid dependence; has been intolerant to 1 or more protocol-specified UC treatmentsRegistry-derived · unreviewed
- Is on treatment with any protocol-specified drugs during the study and meets drug stabilization requirements, as applicableRegistry-derived · unreviewed
Exclusion criteria (12)
- Has a diagnosis of Crohn's Disease (CD) or indeterminate colitis (inflammatory bowel disease (IBD)-undefined) or other types of colitis or enteritis that may confound efficacy assessmentRegistry-derived · unreviewed
- Has a current diagnosis of fulminant colitis and/or toxic megacolonRegistry-derived · unreviewed
- Has UC limited to the rectumRegistry-derived · unreviewed
- Has a current or impending need for colostomy or ileostomyRegistry-derived · unreviewed
- Has had a total proctocolectomy or partial colectomyRegistry-derived · unreviewed
- Has UC exacerbation requiring hospitalization within 2 weeks before ScreeningRegistry-derived · unreviewed
- Has any active infection as specified in the protocolRegistry-derived · unreviewed
- Is known to be infected with hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV)Registry-derived · unreviewed
- Has a history of cancer (except fully treated nonmelanoma skin cell cancers or cervical carcinoma in situ after complete surgical removal) and is disease free for \<5 years before Randomization or has a history of colorectal cancer at any timeRegistry-derived · unreviewed
- Has prior or current evidence of definite colonic dysplasia except for low-grade dysplasia that has been completely removedRegistry-derived · unreviewed
- Has had major surgery within 3 months before Screening or has a major surgery (ie, surgical procedure requiring general anesthesia) planned during the studyRegistry-derived · unreviewed
- Has received protocol-specified prohibited medicationsRegistry-derived · unreviewed
This information can identify a possible match, conflict, or item needing confirmation. Only the study team can determine eligibility.
Study outcomes
Primary outcome
Percentage of Participants Achieving Clinical Remission Per Modified Mayo Score (MMS) at Week 12
Time frame: Week 12
The MMS is a composite score of UC disease activity on a scale of increasing severity from 0-9, calculated by summing three subscores: Endoscopic subscore (ES), scored on a scale of increasing severity from 0 (normal or inactive disease) to 3 (severe disease, such as spontaneous bleeding or ulceration); Stool frequency subscore (SFS), scored on a scale of increasing frequency from 0 (normal number of stools) to 3 (≥5 stools more than normal per day for the participant); and rectal bleeding subscore (RBS), scored on a scale of increasing severity from 0 (no blood seen) to 3 (blood alone passed). Clinical Remission is defined as an ES of 0 or 1 with no friability, RBS of 0, and SFS of 0 or 1 and not greater than the baseline SFS.
Secondary outcome
Percentage of Participants With One or More Adverse Events (AEs)
Time frame: Up to approximately 12 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The percentage of participants who experience an AE will be reported.
Secondary outcome
Percentage of Participants Who Discontinued Study Intervention Due to an AE
Time frame: Up to approximately 12 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The percentage of participants who discontinue study treatment due to an AE will be reported.
Secondary outcome
Percentage of Participants Achieving Clinical Response Per MMS at Week 12
Time frame: Week 12
The MMS is a composite score of UC disease activity on a scale of increasing severity from 0-9, calculated by summing three subscores: ES, scored on a scale of increasing severity from 0 (normal or inactive disease) to 3 (severe disease, such as spontaneous bleeding or ulceration); SFS, scored on a scale of increasing frequency from 0 (normal number of stools) to 3 (≥5 stools more than normal per day for the participant); and RBS, scored on a scale of increasing severity from 0 (no blood seen) to 3 (blood alone passed). Clinical response is defined as an MMS reduction of 2 or more points and 30% or more from baseline, plus a reduction of 1 or more points in RBS or an absolute RBS of 0 or 1.
Secondary outcome
Percentage of Participants With Endoscopic Improvement at Week 12
Time frame: Week 12
Endoscopic improvement is defined as ES of 0 or 1 with no friability. The ES measures UC severity based on endoscopy on a 0-3 scale of increasing severity.
Secondary outcome
Percentage of Participants Achieving Clinical Remission Per Partial Modified Mayo Score (pMMS) at Week 12
Time frame: Week 12
pMMS is a composite score of UC disease activity on a scale of increasing severity from 0-6, calculated by summing two subscores: SFS, scored from 0 (normal number of stools) to 3 (≥5 stools more than normal per day for the participant) and RBS, scored from 0 (no blood seen) to 3 (blood alone passed). Clinical remission per pMMS is defined as an RBS of 0 and SFS of less than or equal to 1.
Secondary outcome
Percentage of Participants Achieving Histologic-Endoscopic Mucosal Improvement (HEMI) at Week 12
Time frame: Week 12
HEMI is defined as a Geboes score of 3.1 or less and ES of 0 or 1 with no friability. The Geboes score is a histologic grading system for inflammation in UC with scores ranging from 0 to 5.4, with higher scores indicating more severe inflammation. ES measures UC severity based on endoscopy, scored from 0 (normal or inactive disease) to 3 (severe disease, such as spontaneous bleeding or ulceration).
Recruiting locations in the United States
Clinnova Research ( Site 1042)
RecruitingAnaheim, California, 92805, United States
Study Coordinator949-889-0249
Southern California Research Center ( Site 1044)
RecruitingCoronado, California, 92118, United States
Study Coordinator619-522-0330
Peak Gastroenterology Associates ( Site 1052)
RecruitingColorado Springs, Colorado, 80907, United States
Study Coordinator719-636-1201
South Denver Gastroenterology, PC ( Site 1068)
RecruitingEnglewood, Colorado, 80113, United States
Study Coordinator303-406-4288
Nature Coast Clinical Research ( Site 1045)
RecruitingInverness, Florida, 34452, United States
Study Coordinator352-341-2100
Research Associates of South Florida - Miami - Southwest 8th Street ( Site 1072)
RecruitingMiami, Florida, 33134, United States
Study Coordinator786-476-8790
Gastroenterology Associates of Central Georgia ( Site 1060)
RecruitingMacon, Georgia, 31201, United States
Study Coordinator478-464-2600
University of Kansas Medical Center ( Site 1077)
RecruitingKansas City, Kansas, 66160, United States
Study Coordinator913-588-6019
Tulane University School of Medicine-Gastroenterology and Hepatology ( Site 1073)
RecruitingNew Orleans, Louisiana, 70112, United States
Study Coordinator504-988-5110
BVL Research - Kansas ( Site 1054)
RecruitingLiberty, Missouri, 64068, United States
Study Coordinator816-222-4241
This study also lists 18 locations outside the United States. They are not shown here.
Central study contacts
Registry dates
- First posted
- Mar 11, 2026
- Primary completion
- Oct 28, 2027
- Overall completion
- Dec 21, 2028
Trial information comes from ClinicalTrials.gov and may change. Confirm current status, eligibility, and site details with the study team. Aidy does not provide medical advice or determine eligibility.