A Phase 1/2 interventional study of XmAb942 and Placebo in Ulcerative Colitis (UC), sponsored by Xencor, Inc.. Recruiting at 114 sites in 19 countries. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Xencor, Inc. · Phase 1/2, Interventional, and Treatment
The Phase 1 study described herein will evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of XmAb942 in healthy volunteers (Parts A and B). Part C of this study will be a Phase 2 study to evaluate XmAb942 in participants with ulcerative colitis (UC).
This study consists of 3 parts, as follows:
Part A: Single ascending dose (SAD) in healthy volunteer participants, will entail administration of XmAb942 or matching placebo at 3 different dose levels of XmAb942.
Part B: Multiple ascending dosing for up to 3 doses, will entail administration of XmAb942 or matching placebo at 2 different dose levels of XmAb942.
Part C: Participants with moderately to severely active UC to receive 3 different dose levels of XmAb942 or placebo during a 12-week induction period and single dose level of XmAb942 during a 40-week maintenance period, followed by a 36 follow-up period.
1,853 studies on the registry are indexed under Colitis, Ulcerative; 472 are open to participants now.
This study's planned enrollment of 270 is above the median of 70 across 1,236 interventional studies indexed under Colitis, Ulcerative.
Browse Colitis, Ulcerative studies →Xencor, Inc. is the lead sponsor of 30 studies on the registry; 7 are open to participants now.
Of its 15 completed or terminated interventional studies of FDA-regulated products, 2 (13%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Parts A and B
Part C
Exclusion Criteria:
Parts A and B
Part C
Other protocol defined inclusion/exclusion criteria apply.
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.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
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.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Active XmAb942 to be administered to healthy volunteers. Single administration of 3 ascending dose (SAD) levels of XmAb942 via SC (3 cohorts) or IV (3 cohorts) administration in 8 participants per cohort, randomized in a 3:1 ratio to active or placebo.
Biological: XmAb942
Placebo Comparator to be administered to healthy volunteers. Single administration of 3 ascending dose (SAD) levels will be randomized in a 3:1 ratio to active or placebo.
Drug: Placebo
Active XmAb942 to be administered to healthy volunteers. Multiple administrations of 2 ascending dose (MAD) levels of XmAb942 via IV administration in 8 participants per cohort, randomized in a 3:1 ratio to active or placebo.
Biological: XmAb942
Placebo Comparator to be administered to healthy volunteers. Multiple administrations of 2 ascending dose (MAD) levels will be randomized in a 3:1 ratio to active or placebo.
Drug: Placebo
Active XmAb942 to be administered to participants with moderately to severely active Ulcerative Colitis
Biological: XmAb942
Placebo comparator to be administered to participants with moderately to severely active Ulcerative Colitis
Drug: Placebo
Antibody
Placebo
Incidence, nature, and severity of treatment emergent adverse events (TEAEs) and serious adverse events (SAEs) of XmAb942 in healthy volunteers (Part A)
Time frame: 20 weeks
Incidence, nature, and severity of treatment emergent adverse events (TEAEs) and serious adverse events (SAEs) of XmAb942 in healthy volunteers (Part B)
Time frame: 28 weeks
Clinical remission based on modified mayo score (MMS), defined as MMS ≤ 2 with Mayo endoscopic score (MES) of 1, rectal bleeding subscore (RBS) of 0, and stool frequency subscore (SFS) of 0-1.
A composite score of ulcerative colitis (UC) disease activity on a scale of increasing severity from 0-9. It is calculated by adding the results from Mayo endoscopic subscore (MES) which measures GI bleeding, stool frequency subscore (SFS) which measures stool frequency per day, and rectal bleeding subscore (RBS), which measures presence of blood during stool passing. Each subscore is a scale of increasing severity from 0 to 3.
Time frame: 12 weeks
Serum PK parameters of XmAb942 in Healthy Volunteers (Part A)
• Cmax (Maximum concentration of drug)
Time frame: up to 20 weeks
Serum PK parameters of XmAb942 in Healthy Volunteers (Part A)
• AUC0-last (Area under the curve drug concentration-time curve to last concentration)
Time frame: up to 20 weeks
Serum PK parameters of XmAb942 in Healthy Volunteers (Part B)
• Cmax (Maximum concentration of drug)
Time frame: up to 28 weeks
Serum PK parameters of XmAb942 in Healthy Volunteers (Part B)
• AUC0-tau AUC within a dosing interval, calculated using the linear trapezoidal rule
Time frame: up to 28 weeks
Incidence and severity of treatment emergent adverse events (TEAEs) and serious adverse events (SAEs) (Part C)
Time frame: 72 weeks
Discontinuations due to TEAEs (Part C)
Time frame: 72 weeks
Endoscopic improvement defined as (MES) of 0 or 1 (Part C).
Time frame: 12 weeks
Change from baseline in MS (Part C).
Time frame: 12 weeks
Clinical response based on MMS score (Part C) defined as decrease from baseline in the MMS of ≥ 2 points and at least a 30% reduction from baseline, and decrease of ≥ 1 point in RBS from baseline or absolute RBS ≤ 1
Time frame: 12 weeks
Histological improvement as determined by change in Robarts Histopathology Index (RHI) scores, ranging from 0 (no disease activity) to 33 (severe disease activity).
Time frame: 12 weeks
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Plan to share: No
No publications or documents are linked to this record.
Started Oct 2024 (actual). Primary completion is estimated for Dec 2027, 38 months after the start.
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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