A Phase 1 interventional study of Ulonivirine in Hepatic Insufficiency, sponsored by Merck Sharp & Dohme LLC. Not yet recruiting. Open to participants aged 18 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-16.
Sponsored by Merck Sharp & Dohme LLC (part of Merck & Co., Inc) · Phase 1, Interventional, and Treatment
The purpose of this study is to evaluate pharmacokinetics (PK) and safety of a single oral dose of ulonivirine in participants with mild or moderate hepatic impairment (HI). It is hypothesized that the area under the plasma concentration-time curve from dosing to (extrapolated) infinity (AUC0-∞) in participants with mild or moderate HI is similar to that of healthy control participants.
113 studies on the registry are indexed under Hepatic Insufficiency; 15 are open to participants now.
This study's planned enrollment of 22 is below the median of 29 across 100 interventional studies indexed under Hepatic Insufficiency.
Browse Hepatic Insufficiency studies →Merck Sharp & Dohme LLC is the lead sponsor of 2,166 studies on the registry; 132 are open to participants now.
Of its 501 completed or terminated interventional studies of FDA-regulated products, 370 (74%) 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.
Mild and Moderate HI (Panels A and B):
Healthy Controls (Panel C):
All Participants (Panels A to C):
Exclusion Criteria:
Mild and Moderate HI (Panels A and B):
Healthy Controls (Panel C):
All Participants (Panel A to C):
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
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.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
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.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
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.
Participants with mild HI receive a single oral dose of ulonivirine 400 mg on Day 1.
Drug: Ulonivirine
Participants with moderate HI receive a single oral dose of ulonivirine 400 mg on Day 1.
Drug: Ulonivirine
Healthy matched control participants receive a single oral dose of ulonivirine 400 mg on Day 1.
Drug: Ulonivirine
Four ulonivirine 100 mg tablets (total dose 400 mg) taken by mouth.
Also known as: MK-8507
Area Under the Plasma Concentration-Time Curve from Dosing to Infinity (AUC0-∞) of Ulonivirine
The AUC0-∞ of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Area Under the Plasma Concentration-Time Curve from Dosing to Last Measurable Concentration (AUC0-last) of Ulonivirine
The AUC0-last of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Maximum Plasma Concentration (Cmax) of Ulonivirine
The Cmax of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Time to Maximum Plasma Concentration (Tmax) of Ulonivirine
The Tmax of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Apparent Plasma Terminal Half-life (t½) of Ulonivirine
The t½ of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Apparent Total Clearance from Plasma After Oral Administration (CL/F) of Ulonivirine
The CL/F of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Apparent Volume of Distribution during Terminal Phase (Vz/F) of Ulonivirine
The Vz/F of ulonivirine will be determined in participants with mild or moderate HI and healthy controls.
Time frame: Predose and 1, 2, 4, 6, 8, 12, 24, 48, 96, 120, 168, 240, 336, and 504 hours postdose
Percentage of Participants with an Adverse Event (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.
Time frame: Up to 21 days
No study locations are listed for this record.
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
Data sharing details ↗ · externaldatasharing-msd.com
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Ulonivirine