A Clinical Study of Islatravir and Ulonivirine for People With HIV-1 Who Have Not Been Treated Before (MK-8591B-062)
A Phase 2/3, Randomized, Active-Controlled, Open-Label (Phase 2) and Double-Blind (Phase 3) Study to Evaluate the Antiretroviral Activity, Safety, and Tolerability of Islatravir (ISL) and Ulonivirine (ULO) Once Weekly Compared With Bictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF) Once Daily in Treatment-Naïve Adult Participants Living With HIV-1
4 other identifiers
interventional
570
7 countries
34
Brief Summary
Researchers are looking for new ways to treat HIV-1 (Human Immunodeficiency Virus Type 1). The usual (standard) treatment for HIV-1 is antiretroviral therapy (ART), which includes taking medicines to lower the amount of HIV-1 in the body. Standard ART helps people live longer, but people must take up to 3 medicines up to twice a day. Standard ART may also cause other health problems. Researchers want to know if a study ART works as well as a standard ART to treat HIV-1. The study ART combines 2 medicines, islatravir and ulonivirine, and is taken once a week. The goals of this study are to learn: 1) If the study ART works as well as a standard ART to treat HIV-1, and 2) About the safety of the study ART and if people tolerate it compared to a standard ART.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_2
Started Dec 2025
Typical duration for phase_2
34 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
December 1, 2025
CompletedFirst Posted
Study publicly available on registry
December 5, 2025
CompletedStudy Start
First participant enrolled
December 18, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
March 21, 2029
ExpectedStudy Completion
Last participant's last visit for all outcomes
April 3, 2030
April 13, 2026
April 1, 2026
3.3 years
December 1, 2025
April 10, 2026
Conditions
Outcome Measures
Primary Outcomes (6)
Phase 2: Percentage of Participants With Human Immunodeficiency Virus Type 1 (HIV-1) Ribonucleic Acid (RNA) <50 Copies/mL at Week 24
Plasma HIV-1 ribonucleic acid (RNA) quantification will be performed at the central laboratory using a polymerase chain reaction (PCR) assay. Percentage of participants with HIV-1 RNA \<50 copies/mL will be reported at week 24.
Week 24
Phase 2: Percentage of Participants Who Experience an Adverse Event (AE) at Week 24
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.
Week 24
Phase 2: Percentage of Participants Who Discontinue Study Intervention Due to an AE at Week 24
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.
Week 24
Phase 3: Percentage of Participants With HIV-1 RNA <50 Copies/mL at Week 48
Plasma HIV-1 RNA quantification will be performed at the central laboratory using a PCR assay. Percentage of participants with HIV-1 RNA \<50 copies/mL will be reported at week 48.
Week 48
Phase 3: Percentage of Participants Who Experience an AE at Week 48
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.
Week 48
Phase 3: Percentage of Participants Who Discontinue Study Intervention Due to an AE at Week 48
An AE is defined as any unfavorable and unintended sign, symptom, disease, or worsening of preexisting condition temporally associated with study treatment and irrespective of causality to study treatment.
Week 48
Secondary Outcomes (24)
Phase 2: Percentage of Participants With HIV-1 RNA <50 Copies/mL at Week 48
Week 48
Phase 2: Percentage of Participants With HIV-1 RNA <50 Copies/mL at Week 96
Week 96
Phase 2: Percentage of Participants With HIV-1 RNA <200 Copies/mL at Week 24
Week 24
Phase 2: Percentage of Participants With HIV-1 RNA <200 Copies/mL at Week 48
Week 48
Phase 2: Percentage of Participants With HIV-1 RNA <200 Copies/mL at Week 96
Week 96
- +19 more secondary outcomes
Study Arms (4)
Phase 2: ISL + ULO
EXPERIMENTALIslatravir (ISL) 2mg and Ulonivirine (ULO) 200mg administered orally once weekly (qw) for 96 weeks
Phase 2: BIC/FTC/TAF
ACTIVE COMPARATORBictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF) 50/200/25 mg, administered orally once daily (qd) for 96 weeks
Phase 3: ISL/ULO and Placebo to BIC/FTC/TAF
EXPERIMENTALISL/ULO fixed dose combination (2/200 mg), administered orally qw, and matching placebo to BIC/FTC/TAF administered orally qd for 96 weeks
Phase 3: BIC/FTC/TAF and Placebo to ISL/ULO
ACTIVE COMPARATORBIC/FTC/TAF 50/200/25 mg, administered orally qd, and matching placebo to ISL/ULO administered orally qw for 96 weeks
Interventions
BIC/FTC/TAF-matching placebo oral tablet administered qd for 96 weeks
ISL/ULO-matching placebo oral tablets administered qw for 96 weeks
ISL/ULO fixed-dose combination 2 mg/200 mg oral tablet administered qw for 96 weeks
ISL 2 x 1 mg oral capsules administered qw for 96 weeks
ULO 2 x 100 mg oral tablets administered qw for 96 weeks
BIC/FTC/TAF 50/200/25 mg oral tablet administered qd for 96 weeks
Eligibility Criteria
You may qualify if:
- Phase 2: Is human immunodeficiency virus type 1 (HIV-1) positive with Plasma HIV-1 ribonucleic acid (RNA) ≥500 and ≤100,000 copies/mL.
- Phase 3: Is HIV-1 positive with Plasma HIV-1 RNA ≥500 copies/mL.
- Phase 2: Has cluster of differentiation 4-positive (CD4+) T-cell count ≥200 cells/mm\^3.
- Is naïve to antiretroviral therapy (ART), defined as having received no prior therapy with any antiretroviral agent following a diagnosis of HIV 1 infection.
You may not qualify if:
- Has human immunodeficiency virus type 2 (HIV-2) infection.
- Has a diagnosis of an active acquired immune deficiency syndrome (AIDS)-defining opportunistic infection.
- Has active hepatitis C virus (HCV) or active hepatitis B virus (HBV) infection.
- Has a history of malignancy ≤5 years prior to providing documented informed consent except for adequately treated basal cell or squamous cell skin cancer, in situ cervical or in situ anal cancer, or cutaneous Kaposi's sarcoma.
- Has prior exposure to islatravir (ISL) or ulonivirine (ULO) for any duration any time prior to Day 1.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (34)
Vivent Health ( Site 1519)
Denver, Colorado, 80246, United States
Whitman-Walker Institute ( Site 1538)
Washington D.C., District of Columbia, 20032, United States
Midway Immunology and Research Center ( Site 1503)
Ft. Pierce, Florida, 34982, United States
CAN Community Health- Miami Gardens ( Site 1549)
Miami Gardens, Florida, 33055, United States
Orlando Immunology Center ( Site 1501)
Orlando, Florida, 32803, United States
CAN Community Health ( Site 1510)
Sarasota, Florida, 34237, United States
Triple O Research Institute ( Site 1505)
West Palm Beach, Florida, 33407, United States
Metro Infectious Diseases Consultants L.L.C. ( Site 1509)
Decatur, Georgia, 30033, United States
Mercer university, Department of internal medicine-Clinical Research ( Site 1512)
Macon, Georgia, 31201, United States
KC CARE Health Center ( Site 1506)
Kansas City, Missouri, 64111, United States
ID Care ( Site 1507)
Hillsborough, New Jersey, 08844, United States
Atrium Health Infectious Disease Kenilworth - Charlotte ( Site 1533)
Charlotte, North Carolina, 28204, United States
Regional Center for Infectious Diseases ( Site 1516)
Greensboro, North Carolina, 27401, United States
The Ohio State University ( Site 1536)
Columbus, Ohio, 43210, United States
University of Pennsylvania Perelman School of Medicine ( Site 1508)
Philadelphia, Pennsylvania, 19104, United States
Saint Hope Foundation, Inc. ( Site 1504)
Bellaire, Texas, 77401, United States
Prism Health North Texas, Oak Cliff Health Center ( Site 1514)
Dallas, Texas, 75208, United States
North Texas Infectious Diseases Consultants ( Site 1500)
Dallas, Texas, 75246, United States
Texas Center for Infectious Disease Associates ( Site 1502)
Fort Worth, Texas, 76104, United States
DCOL Center for Clinical Research ( Site 1511)
Longview, Texas, 75605, United States
Centro Medico Dra. Laura Maffei- Investigacion Clinica Aplicada ( Site 3102)
Caba, Buenos Aires, C1425AGC, Argentina
Spectrum Health ( Site 3307)
Vancouver, British Columbia, V6Z 2T1, Canada
Gestion clinique médicale l'Actuel ( Site 3303)
Montreal, Quebec, H2L 4P9, Canada
Bordeaux University Hospital - Pellegrin ( Site 3605)
Bordeaux, Gironde, 33000, France
Centre Hospitalier Universitaire de Toulouse - Hôpital Purpan ( Site 3608)
Toulouse, Haute-Garonne, 31059, France
Centre Hospitalier Universitaire de Nantes - L' Hopital l'hôtel-Dieu-Infectious Disease ( Site 3606)
Nantes, Pays de la Loire Region, 44093, France
HOPITAL DE LA CROIX ROUSSE ( Site 3613)
Lyon, Rhone, 69317, France
Hôpital Avicenne ( Site 3602)
Bobigny, Île-de-France Region, 93000, France
Hôpital Bichat - Claude-Bernard ( Site 3601)
Paris, Île-de-France Region, 75018, France
Clínica Médica Especializada en Pediatría e Infectología Pediátrica - Dr. Mario Melgar ( Site 3801)
Guatemala City, 01009, Guatemala
MEDI-K ( Site 3803)
Guatemala City, 01009, Guatemala
CELAN,S.A ( Site 3802)
Guatemala City, 01010, Guatemala
Wentworth Hospital ( Site 4303)
Durban, KwaZulu-Natal, 4052, South Africa
Hospital Universitari Vall d'Hebron ( Site 3402)
Barcelona, 08035, Spain
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Medical Director
Merck Sharp & Dohme LLC
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Masking Details
- Phase 2: no masking Phase 3: Participant, Sponsor, and Investigator are masked
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
December 1, 2025
First Posted
December 5, 2025
Study Start
December 18, 2025
Primary Completion (Estimated)
March 21, 2029
Study Completion (Estimated)
April 3, 2030
Last Updated
April 13, 2026
Record last verified: 2026-04
Data Sharing
- IPD Sharing
- Will share
https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf