Oral ISL QM as PrEP in Cisgender Women at High Risk for HIV-1 Infection (MK-8591-022) (Impower-022)
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ClinicalTrials.gov Identifier: NCT04644029 |
Recruitment Status :
Recruiting
First Posted : November 25, 2020
Last Update Posted : April 12, 2021
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
HIV-I Human Immunodeficiency Virus Type 1 Prophylaxis | Drug: ISL Drug: Placebo to FTC/TDF Drug: FTC/TDF Drug: Placebo to ISL | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 4500 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Triple (Participant, Care Provider, Investigator) |
Masking Description: | A double-blinding technique with in-house blinding will be used. ISL and FTC/TDF and FTC/TAF will be packaged identically relative to their matching placebos so that blind is maintained. The participant, the investigator, and Sponsor personnel or delegate(s) who are involved in the study intervention administration or clinical evaluation of the participants are unaware of the intervention assignments. |
Primary Purpose: | Prevention |
Official Title: | A Phase 3, Randomized, Active-Controlled, Double-blind Clinical Study to Evaluate the Efficacy and Safety of Oral Islatravir Once-Monthly as Preexposure Prophylaxis in Cisgender Women at High Risk for HIV-1 Infection |
Actual Study Start Date : | February 24, 2021 |
Estimated Primary Completion Date : | July 5, 2024 |
Estimated Study Completion Date : | July 5, 2024 |
Arm | Intervention/treatment |
---|---|
Experimental: ISL QM
ISL (islatravir) once monthly AND placebo to FTC/TDF (emtricitabine/tenofovir disoproxil fumarate) once daily
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Drug: ISL
Oral 60mg tablet administered once monthly
Other Name: MK-8591 Drug: Placebo to FTC/TDF 0mg tablet administered once daily |
Active Comparator: FTC/TDF QD
FTC/TDF (emtricitabine/tenofovir disoproxil fumarate) once daily AND placebo to ISL (islatravir) once monthly
|
Drug: FTC/TDF
200/245mg or 200/300mg tablet administered orally once daily
Other Names:
Drug: Placebo to ISL 0mg tablet administered orally once monthly |
- Incidence Rate Per Year of Confirmed HIV-1 Infections [ Time Frame: Up to approximately 36 months ]Incidence rate per year of confirmed HIV-1 infections is the number of participants with confirmed HIV-1 infections divided by the total person-years of follow-up time to HIV-1 infection status. The primary analysis will compare the incidence rate per year of confirmed HIV-1 Infections between the ISL QM arm participants and incidence rate per year of confirmed HIV-1 Infections in the FTC/TDF QD arm participants. HIV serology tests and polymerase chain reaction (PCR) tests will be done at pre-specified timepoints to confirm HIV-1 infection.
- Percentage of Participants Who Experienced One or More Adverse Events [ Time Frame: Up to approximately 37 months ]An adverse event (AE) is any untoward medical occurrence in a study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign, symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
- Percentage of Participants Who Discontinued Treatment Due to an Adverse Event [ Time Frame: Up to approximately 36 months ]An adverse event (AE) is any untoward medical occurrence in a study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign, symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
- Incidence Rate per Year of Confirmed HIV-1 Infections Among Participants [ Time Frame: Up to approximately 36 months ]Incidence rate per year of confirmed HIV-1 infections is the number of participants with confirmed HIV-1 infections divided by the total person-years of follow-up time to HIV-1 infection status. The secondary analysis will compare the incidence rate per year of confirmed HIV-1 Infections between the ISL QM arm participants and the background incidence rate calculated from screened participants. The background incidence rate will be estimated using tests based on biomarkers that can differentiate "recent" from "nonrecent" infections in the population screened for this study.

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Ages Eligible for Study: | 16 Years to 45 Years (Child, Adult) |
Sexes Eligible for Study: | Female |
Gender Based Eligibility: | Yes |
Gender Eligibility Description: | Assigned female sex at birth and is cisgender |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- Confirmed HIV-uninfected based on negative HIV-1/HIV-2 test results before randomization.
- Sexually active with a male sexual partner in the 30 days prior to screening.
- High risk for HIV-1 infection.
- Not pregnant or breastfeeding, and one of the following conditions applies: Not a woman of childbearing potential (WOCBP) or is a WOCBP and is using an acceptable contraceptive method during the intervention period and for at least 42 days after the last dose.
- A WOCBP must have a negative pregnancy test within 24 hours prior to the first dose of study intervention.
Exclusion Criteria:
- Hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator.
- Active hepatitis B virus (HBV) infection.
- Current or chronic history of liver disease.
- History of malignancy within 5 years of screening except for adequately-treated basal cell or squamous cell skin cancer, or in situ cervical cancer.
- Past or current use of cabotegravir.
- Currently participating in or has participated in an interventional clinical study with an investigational compound or device, within 30 days prior to Day 1.
- Expecting to conceive or donate eggs at any time during the study.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04644029
Contact: Toll Free Number | 1-888-577-8839 | Trialsites@merck.com |
United States, District of Columbia | |
MedStar Health Research Institute (MedStar Physician Based R-MedStar Washington Hospital Center ( Si | Recruiting |
Washington, District of Columbia, United States, 20010 | |
Contact: Study Coordinator 202-877-0486 | |
United States, Florida | |
Orlando Immunology Center ( Site 0068) | Recruiting |
Orlando, Florida, United States, 32803 | |
Contact: Study Coordinator 40764739602115 | |
United States, Mississippi | |
The University of Mississippi Medical Center ( Site 0065) | Recruiting |
Jackson, Mississippi, United States, 39216 | |
Contact: Study Coordinator 601-815-5009 | |
United States, Missouri | |
KC CARE Health Center-Clinical Trials ( Site 0059) | Recruiting |
Kansas City, Missouri, United States, 64111 | |
Contact: Study Coordinator 816-777-2759 | |
United States, Texas | |
Prism Health North Texas, Oak Cliff Health Center ( Site 0070) | Recruiting |
Dallas, Texas, United States, 75208 | |
Contact: Study Coordinator 972-807-7370 |
Study Director: | Medical Director | Merck Sharp & Dohme Corp. |
Responsible Party: | Merck Sharp & Dohme Corp. |
ClinicalTrials.gov Identifier: | NCT04644029 |
Other Study ID Numbers: |
8591-022 MK-8591-022 ( Other Identifier: Merck ) |
First Posted: | November 25, 2020 Key Record Dates |
Last Update Posted: | April 12, 2021 |
Last Verified: | April 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | http://engagezone.msd.com/doc/ProcedureAccessClinicalTrialData.pdf |
URL: | http://engagezone.msd.com/ds_documentation.php |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Preexposure prophylaxis (PrEP) Prevention |
Acquired Immunodeficiency Syndrome HIV Infections Immunologic Deficiency Syndromes Immune System Diseases Lentivirus Infections Retroviridae Infections RNA Virus Infections Virus Diseases Sexually Transmitted Diseases, Viral Sexually Transmitted Diseases Slow Virus Diseases |
Tenofovir Emtricitabine Emtricitabine, Tenofovir Disoproxil Fumarate Drug Combination Antiviral Agents Anti-Infective Agents Reverse Transcriptase Inhibitors Nucleic Acid Synthesis Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Anti-Retroviral Agents Anti-HIV Agents |