A Clinical Study of Islatravir and Ulonivirine for People With HIV-1 Who Have Not Been Treated Before (MK-8591B-062)

NCT07266831 | Recruiting Phase 2 DMC FDA Drug

• 4 other identifiers: 8591B-062U1111-1323-46892025-522519-40MK-8591B-062
• Study Type: interventional
• Target: 570
• Locations: 9 countries
• Sites: 56

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.

Conditions

Human Immunodeficiency Virus Type 1 (HIV-1) Infection

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

Study Arms (4)

Phase 2: ISL + ULO

EXPERIMENTAL

Islatravir (ISL) 2mg and Ulonivirine (ULO) 200mg administered orally once weekly (qw) for 96 weeks

Drug: ISL; Drug: ULO

Phase 2: BIC/FTC/TAF

ACTIVE COMPARATOR

Bictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF) 50/200/25 mg, administered orally once daily (qd) for 96 weeks

Drug: BIC/FTC/TAF

Phase 3: ISL/ULO and Placebo to BIC/FTC/TAF

EXPERIMENTAL

ISL/ULO fixed dose combination (2/200 mg), administered orally qw, and matching placebo to BIC/FTC/TAF administered orally qd for 96 weeks

Drug: Placebo for BIC/FTC/TAF; Drug: ISL/ULO

Phase 3: BIC/FTC/TAF and Placebo to ISL/ULO

ACTIVE COMPARATOR

BIC/FTC/TAF 50/200/25 mg, administered orally qd, and matching placebo to ISL/ULO administered orally qw for 96 weeks

Drug: BIC/FTC/TAF; Drug: Placebo to ISL/ULO

Interventions

Placebo for BIC/FTC/TAF DRUG

BIC/FTC/TAF-matching placebo oral tablet administered qd for 96 weeks

Phase 3: ISL/ULO and Placebo to BIC/FTC/TAF

ISL/ULO DRUG

ISL/ULO fixed-dose combination 2 mg/200 mg oral tablet administered qw for 96 weeks

Also known as: MK-8591B

Phase 3: ISL/ULO and Placebo to BIC/FTC/TAF

ISL DRUG

ISL 2 x 1 mg oral capsules administered qw for 96 weeks

Also known as: islatravir, MK-8591

Phase 2: ISL + ULO

ULO DRUG

ULO 2 x 100 mg oral tablets administered qw for 96 weeks

Also known as: ulonivirine, MK-8507

Phase 2: ISL + ULO

Placebo to ISL/ULO DRUG

ISL/ULO-matching placebo oral tablets administered qw for 96 weeks

Phase 3: BIC/FTC/TAF and Placebo to ISL/ULO

BIC/FTC/TAF DRUG

BIC/FTC/TAF 50/200/25 mg oral tablet administered qd for 96 weeks

Also known as: bictegravir/emtricitabine/tenofovir alafenamide, BIKTARVY®

Phase 2: BIC/FTC/TAF; Phase 3: BIC/FTC/TAF and Placebo to ISL/ULO

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

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.

Sponsors & Collaborators

• Merck Sharp & Dohme LLC: lead

Study Sites (56)

Ruane Clinical Research Group, Inc. ( Site 1513)

Los Angeles, California, 90036, United States

RECRUITING

Vivent Health ( Site 1519)

Denver, Colorado, 80246, United States

RECRUITING

Whitman-Walker Institute ( Site 1538)

Washington D.C., District of Columbia, 20032, United States

RECRUITING

Midway Immunology and Research Center ( Site 1503)

Ft. Pierce, Florida, 34982, United States

RECRUITING

CAN Community Health- Miami Gardens ( Site 1549)

Miami Gardens, Florida, 33055, United States

RECRUITING

Orlando Immunology Center ( Site 1501)

Orlando, Florida, 32803, United States

RECRUITING

CAN Community Health ( Site 1510)

Sarasota, Florida, 34237, United States

RECRUITING

Triple O Research Institute ( Site 1505)

West Palm Beach, Florida, 33407, United States

RECRUITING

Metro Infectious Diseases Consultants L.L.C. ( Site 1509)

Decatur, Georgia, 30033, United States

RECRUITING

Mercer university, Department of internal medicine-Clinical Research ( Site 1512)

Macon, Georgia, 31201, United States

RECRUITING

Rush University Medical Center-Infectious Disease ( Site 1522)

Chicago, Illinois, 60612, United States

RECRUITING

Henry Ford Hospital ( Site 1535)

Detroit, Michigan, 48202, United States

RECRUITING

KC CARE Health Center ( Site 1506)

Kansas City, Missouri, 64111, United States

RECRUITING

ID Care ( Site 1507)

Hillsborough, New Jersey, 08844, United States

RECRUITING

Atrium Health Infectious Disease Kenilworth - Charlotte ( Site 1533)

Charlotte, North Carolina, 28204, United States

RECRUITING

Regional Center for Infectious Diseases ( Site 1516)

Greensboro, North Carolina, 27401, United States

RECRUITING

The Ohio State University ( Site 1536)

Columbus, Ohio, 43210, United States

RECRUITING

University of Pennsylvania Perelman School of Medicine ( Site 1508)

Philadelphia, Pennsylvania, 19104, United States

RECRUITING

Saint Hope Foundation, Inc. ( Site 1504)

Bellaire, Texas, 77401, United States

RECRUITING

Prism Health North Texas, Oak Cliff Health Center ( Site 1514)

Dallas, Texas, 75208, United States

RECRUITING

North Texas Infectious Diseases Consultants ( Site 1500)

Dallas, Texas, 75246, United States

RECRUITING

Texas Center for Infectious Disease Associates ( Site 1502)

Fort Worth, Texas, 76104, United States

RECRUITING

DCOL Center for Clinical Research ( Site 1511)

Longview, Texas, 75605, United States

RECRUITING

Harborview Medical Center ( Site 1526)

Seattle, Washington, 98104, United States

RECRUITING

Centro Medico Dra. Laura Maffei- Investigacion Clinica Aplicada ( Site 3102)

Caba, Buenos Aires, C1425AGC, Argentina

RECRUITING

Fundación Huesped ( Site 3100)

CABA, Buenos Aires, C1427CEA, Argentina

RECRUITING

Instituto de Investigaciones Clinicas Mar del Plata ( Site 3103)

Mar del Plata, Buenos Aires, B7600FZN, Argentina

RECRUITING

Fundación IDEAA ( Site 3101)

Buenos Aires, Buenos Aires F.D., C1405CKC, Argentina

RECRUITING

Instituto CAICI SRL ( Site 3106)

Rosario, Santa Fe Province, S2000PBJ, Argentina

RECRUITING

Clínica Mayo de Urgencias Médicas Cruz Blanca S.R.L ( Site 3105)

San Miguel de Tucumán, Tucumán Province, T4000IHE, Argentina

RECRUITING

Spectrum Health ( Site 3307)

Vancouver, British Columbia, V6Z 2T1, Canada

RECRUITING

Gestion clinique médicale l'Actuel ( Site 3303)

Montreal, Quebec, H2L 4P9, Canada

RECRUITING

Biomedica Research Group ( Site 4201)

Santiago, Region M. de Santiago, 7500710, Chile

RECRUITING

Clínica Universidad de Los Andes ( Site 4207)

Santiago, Region M. de Santiago, 7620157, Chile

RECRUITING

Espacio Eme ( Site 4202)

Santiago, Region M. de Santiago, 7770086, Chile

RECRUITING

Bordeaux University Hospital - Pellegrin ( Site 3605)

Bordeaux, Gironde, 33000, France

RECRUITING

Centre Hospitalier Universitaire de Toulouse - Hôpital Purpan ( Site 3608)

Toulouse, Haute-Garonne, 31059, France

RECRUITING

Centre Hospitalier Universitaire de Nantes - L' Hopital l'hôtel-Dieu-Infectious Disease ( Site 3606)

Nantes, Pays de la Loire Region, 44093, France

RECRUITING

HOPITAL DE LA CROIX ROUSSE ( Site 3613)

Lyon, Rhone, 69317, France

RECRUITING

Hôpital Avicenne ( Site 3602)

Bobigny, Île-de-France Region, 93000, France

RECRUITING

Hôpital Saint-Louis ( Site 3600)

Paris, Île-de-France Region, 75010, France

RECRUITING

Hôpital Bichat - Claude-Bernard ( Site 3601)

Paris, Île-de-France Region, 75018, France

RECRUITING

Clínica Médica Especializada en Pediatría e Infectología Pediátrica - Dr. Mario Melgar ( Site 3801)

Guatemala City, 01009, Guatemala

RECRUITING

MEDI-K ( Site 3803)

Guatemala City, 01009, Guatemala

RECRUITING

CELAN,S.A ( Site 3802)

Guatemala City, 01010, Guatemala

RECRUITING

Morales Vargas Centro de Investigacion, S.C. ( Site 4502)

León, Guanajuato, 37000, Mexico

RECRUITING

Arké SMO S.A de C.V ( Site 4505)

Veracruz, 91910, Mexico

RECRUITING

Josha Research ( Site 4302)

Bloemfontein, Free State, 9301, South Africa

RECRUITING

Wentworth Hospital ( Site 4303)

Durban, KwaZulu-Natal, 4052, South Africa

RECRUITING

Be Part Yoluntu Centre ( Site 4300)

Mbekweni, Paarl, Western Cape, 7646, South Africa

RECRUITING

Hospital Universitario La Paz ( Site 3404)

Madrid, Madrid, Comunidad de, 28029, Spain

RECRUITING

Consorcio Hospital General Universitario de Valencia ( Site 3406)

Valencia, Valenciana, Comunitat, 46014, Spain

RECRUITING

Hospital Universitari Vall d'Hebron ( Site 3402)

Barcelona, 08035, Spain

RECRUITING

HOSPITAL CLÍNIC DE BARCELONA ( Site 3400)

Barcelona, 08036, Spain

RECRUITING

Hospital Universitario 12 de Octubre ( Site 3405)

Madrid, 28041, Spain

RECRUITING

Complejo Hospitalario Virgen De La Victoria ( Site 3409)

Málaga, 29010, Spain

RECRUITING

Related Links

• Merck Clinical Trials Information
• Plain Language Summary

MeSH Terms

Conditions

Acquired Immunodeficiency Syndrome; Infections

Interventions

islatravir; ulonivirine; bictegravir, emtricitabine, tenofovir alafenamide, drug combination

Condition Hierarchy (Ancestors)

HIV Infections; Blood-Borne Infections; Communicable Diseases; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Lentivirus Infections; Retroviridae Infections; RNA Virus Infections; Virus Diseases; Slow Virus Diseases; Genital Diseases; Urogenital Diseases; Immunologic Deficiency Syndromes; Immune System Diseases

Study Officials

• Medical Director

  Merck Sharp & Dohme LLC

  STUDY DIRECTOR

Central Study Contacts

Toll Free Number

CONTACT

1-888-577-8839; Trialsites@msd.com

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: June 8, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will share

Locations

CL (3); ES (6); ZA (3); AR (6); FR (7); US (24); GU (3); CA (2); ME (2)