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Active, Not Recruiting

NCT Number: NCT06891066

A Study of Islatravir (ISL) and Ulonivirine (ULO) Once Weekly (QW) in Virologically Suppressed Adults With Human Immunodeficiency Virus Type 1 (HIV-1) (MK-8591B-060)

Investigators are trying to find better treatments for people with HIV-1. In this clinical study, investigators want to see how well a new treatment called ISL+ULO, taken once a week, works compared to an existing treatment called BIC/FTC/TAF, which is taken every day. Investigators will check how many people still have a high level of the virus in their blood after 24 weeks. The investigators also want to understand if the new treatment, MK-8591B, is safe and how well people can handle it.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

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Key information

Conditions

Human Immunodeficiency Virus Type 1 (HIV-1) Infection Acquired Immunodeficiency Syndrome Blood-Borne Infections Communicable Diseases Genital Diseases HIV Infections Immune System Diseases Immunologic Deficiency Syndromes Infections Lentivirus Infections RNA Virus Infections Retroviridae Infections Sexually Transmitted Diseases Sexually Transmitted Diseases, Viral Slow Virus Diseases Urogenital Diseases Virus Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Momentum Clinical Research - Darlinghurst ( Site 4260), Darlinghurst, New South Wales, Australia

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion:

The main inclusion criteria include but are not limited to the following:

  • Has been receiving Bictegravir/Emtricitabine/Tenofovir alafenamide (BIC/FTC/TAF) therapy with documented viral suppression [Human immunodeficiency virus type 1 (HIV-1) ribonucleic acid (RNA) <50 copies/mL] for ≥6 months prior to providing documented informed consent and has no history of prior virologic treatment failure on any past or current regimen.

Exclusion:

The main exclusion criteria include but are not limited to the following:

  • 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) coinfection.
  • Has hepatitis B virus (HBV) coinfection.
  • 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.

Treatment and study plan

ISL

Drug

ISL 1mg oral capsule will be administered as 2mg orally (each capsule 1mg) as part of ISL and ULO combination to group 1 participants for 96 weeks and for group 2 participants in part 2 of the study from 49 to 96 weeks.

Other names: MK-8591, Islatravir

ULO

Drug

ULO 100mg oral tablet will be administered as 200mg (2 tablets) orally as part of ISL and ULO combination to group 1 participants for 96 weeks and for group 2 participants in part 2 of the study from 49 to 96 weeks.

Other names: MK-8507, Ulonivirine.

BIC/FTC/TAF

Drug

BIC 50mg oral tablet/FTC 200mg oral tablet/TAF 25 mg oral tablet administered orally to group 2 participants for 48 weeks in part 1 of the study.

Other names: BIKTARVY®

Primary outcomes

  1. Percentage of Participants With HIV-1 RNA ≥50 copies/mL at Week 24

    Time frame: 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.

  2. Percentage of Participants who Experience an Adverse Event (AE)

    Time frame: Up to ~ 96 weeks

    An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The percentage of participants who experience an AE will be reported.

  3. Percentage of Participants Discontinuing Study Treatment due to AEs

    Time frame: Up to ~ 96 weeks

    An AE is any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The percentage of participants who discontinue study treatment due to an AE will be reported.

Secondary outcomes

  1. Percentage of Participants With HIV-1 RNA ≥50 copies/mL at Week 48

    Time frame: Week 48

    Plasma HIV-1 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 48.

  2. Percentage of Participants With HIV-1 RNA <50 copies/mL at Week 24

    Time frame: Week 24

    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 24.

  3. Percentage of Participants With HIV-1 RNA <50 copies/mL at Week 48

    Time frame: 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.

  4. Percentage of Participants With HIV-1 RNA <200 copies/mL at Week 24

    Time frame: Week 24

    Plasma HIV-1 RNA quantification will be performed at the central laboratory using a PCR assay. Percentage of participants with HIV-1 RNA <200 copies/mL will be reported at week 24.

  5. Percentage of Participants With HIV-1 RNA <200 copies/mL at Week 48

    Time frame: 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 <200 copies/mL will be reported at week 48.

  6. Percentage of Participants With HIV-1 RNA ≥50 copies/mL at Week 96

    Time frame: Week 96

    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 96.

  7. Percentage of Participants With HIV-1 RNA <50 copies/mL at Week 96

    Time frame: Week 96

    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 96.

  8. Percentage of Participants With HIV-1 RNA <200 copies/mL at Week 96

    Time frame: Week 96

    Plasma HIV-1 RNA quantification will be performed at the central laboratory using a PCR assay. Percentage of participants with HIV-1 RNA <200 copies/mL will be reported at week 96.

  9. Mean Change From Baseline in CD4+ T-cell Count at Week 24

    Time frame: Week 24

    The mean change from baseline in CD4+ T-cell count will be calculated at each applicable time point at which CD4+ T-cell count is collected with primary interest at 24 weeks. Blood samples are taken for this purpose. Baseline measurements are defined as the Day 1 value for each participant.

  10. Mean Change From Baseline in CD4+ T-cell Count at Week 48

    Time frame: Week 48

    The mean change from baseline in CD4+ T-cell count will be calculated at each applicable time point at which CD4+ T-cell count is collected with primary interest at 48 weeks. Blood samples are taken for this purpose. Baseline measurements are defined as the Day 1 value for each participant.

  11. Mean Change From Baseline in CD4+ T-cell Count at Week 96

    Time frame: Week 96

    The mean change from baseline in CD4+ T-cell count will be calculated at each applicable time point at which CD4+ T-cell count is collected with primary interest at 96 weeks. Blood samples are taken for this purpose. Baseline measurements are defined as the Day 1 value for each participant.

  12. Percentage of Participants With Development of Viral Drug Resistance to any Component of Study Intervention at Week 24

    Time frame: Week 24

    Antiviral drug resistance is the reduced susceptibility of the virus to the study intervention. Participants with HIV-1 RNA ≥400 copies/mL will be included in the resistance analyses. Participants who have test results showing signs of viral resistance will also be included for analysis, irrespective of the viral load. Percentage of participants in each treatment group who have evidence of resistance-associated substitutions will be analyzed at week 24.

  13. Percentage of Participants With Development of Viral Drug Resistance to any Component of Study Intervention at Week 48

    Time frame: Week 48

    Antiviral drug resistance is the reduced susceptibility of the virus to the study intervention. Participants with HIV-1 RNA ≥400 copies/mL will be included in the resistance analyses. Participants who have test results showing signs of viral resistance will also be included for analysis, irrespective of the viral load. Percentage of participants in each treatment group who have evidence of resistance-associated substitutions will be analyzed at week 48.

  14. Percentage of Participants With Development of Viral Drug Resistance to any Component of Study Intervention at Week 96

    Time frame: Week 96

    Antiviral drug resistance is the reduced susceptibility of the virus to the study intervention. Participants with HIV-1 RNA ≥400 copies/mL will be included in the resistance analyses. Participants who have test results showing signs of viral resistance will also be included for analysis, irrespective of the viral load. Percentage of participants in each treatment group who have evidence of resistance-associated substitutions will be analyzed at week 96.

Sponsors and collaborators

Lead sponsor

Merck Sharp & Dohme LLC

Industry

Registry information

Official study title

A Phase 2b, Randomized, Active-Controlled, Open-Label Clinical Study to Evaluate a Switch to Islatravir (ISL) and Ulonivirine (ULO) Once Weekly in Adults With HIV-1 Virologically Suppressed on Bictegravir/Emtricitabine/Tenofovir Alafenamide (BIC/FTC/TAF) Once Daily

Important dates

Study start
2025
Primary completion
2027
Study completion
2031
First posted
Mar 24, 2025
Registry last updated
Oct 16, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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