A Phase 2 interventional study of MK-8690 and Placebo in Colitis Ulcerative and Ulcerative Colitis, sponsored by Merck Sharp & Dohme LLC. Recruiting at 43 sites in 12 countries. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-11-12.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 2, Interventional, and Treatment
Among 13 studies in Colitis, Ulcerative by Merck & Co., Inc — 2 open to participants now, 3 under way, 2 of them phase 3. Colitis, Ulcerative · Merck & Co., Inc.
Among the 13 studies in Colitis, Ulcerative by Merck & Co., Inc, this one is the 6th largest by planned enrollment of the 11 interventional ones that give a count, is the only one that started in 2026, is one of 2 in phase 2, and was the 13th registered.
1,854 studies on the registry are indexed under Colitis, Ulcerative; 473 are open to participants now.
Browse Colitis, Ulcerative studies →2 of the 13 studies in Colitis, Ulcerative by Merck & Co., Inc are open now, in 12 countries. Recruiting first, the newest first:
Merck Sharp & Dohme LLC · Sites in United States, Czechia, France and 4 more countries
By country, each count listing its studies:
Of the 307 Colitis, Ulcerative studies recruiting now, 134 (44%) set no upper age limit and 136 (44%) stop at 75 or younger; 71 take children under 18; 41 take healthy volunteers.
This study: 18 Years to 75 Years · all sexes · no healthy volunteers.
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13 studies; the count open now beside each. This study's row is marked.
First in 2007; this study’s year is marked. 1 started in 2026.
By drug class, each counting the studies that test any of its medicines:
This study's planned enrollment of 100 is above the median of 70 across 1,237 interventional studies indexed under Colitis, Ulcerative.
Median enrollment 100 across the 11 interventional studies, 1,120 across the 2 observational. Of the 9 that completed or were terminated, 8 (89%) have results posted.
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This study is registered under Merck Sharp & Dohme LLC, one of the names counted as Merck & Co., Inc. Under that name alone:
Merck Sharp & Dohme LLC is the lead sponsor of 2,166 studies on the registry; 131 are open to participants now.
Of its 502 completed or terminated interventional studies of FDA-regulated products, 370 (74%) have results posted.
1 of the studies in Colitis, Ulcerative by Merck & Co., Inc that are under way reach primary completion within a year, 0 of them phase 3. Phase 3 first, then by date:
| Study | Primary completion |
|---|---|
| NCT07463183Merck Sharp & Dohme LLCA Study to Evaluate Efficacy and Safety of MK-8690 in Participants With Moderately to Severely Active Ulcerative Colitis (MK-8690-002) | 2027-10-28 |
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Among the 13 studies in Colitis, Ulcerative by Merck & Co., Inc, from their registry updates:
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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.
The main inclusion criteria include but are not limited to the following:
The main exclusion criteria include but are not limited to the following:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive MK-8690 via subcutaneous injection for 12 weeks.
Drug: MK-8690
Participants will receive placebo via subcutaneous injection for 12 weeks.
Other: Placebo
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.
Drug: 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.
Drug: MK-8690
Solution for subcutaneous injection
Also known as: PRA052
Solution for subcutaneous injection
Percentage of Participants Achieving Clinical Remission Per Modified Mayo Score (MMS) at 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.
Time frame: Week 12
Percentage of Participants With One or More Adverse Events (AEs)
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.
Time frame: Up to approximately 12 months
Percentage of Participants Who Discontinued Study Intervention Due to an AE
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.
Time frame: Up to approximately 12 months
Percentage of Participants Achieving Clinical Response Per MMS at 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.
Time frame: Week 12
Percentage of Participants With Endoscopic Improvement at 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.
Time frame: Week 12
Percentage of Participants Achieving Clinical Remission Per Partial Modified Mayo Score (pMMS) at 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.
Time frame: Week 12
Percentage of Participants Achieving Histologic-Endoscopic Mucosal Improvement (HEMI) at 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).
Time frame: Week 12
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Data sharing details ↗ · externaldatasharing-msd.com
Started Mar 2026 (actual). Primary completion is estimated for Oct 2027, 19 months after the start.
Of 110 industry-sponsored phase 2 interventional studies under Colitis, Ulcerative, half reached primary completion within 27 months of starting (the median), counting those still running; a quarter within 21 and three quarters within 35. This study's planned 19 months is below that.
Counting every sponsor, half of 154 studies reached it within 28 months; a quarter within 22 and three quarters within 43.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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