Radiopaque Matrix MK-8591 Implant in Participants at Low-Risk for Human Immunodeficiency Virus Type 1 (HIV-1) Infection (MK-8591-043)

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the safety, tolerability, and pharmacokinetics (PK) of an islatravir (ISL)-eluting implant. Participants will receive an implant placed in the upper arm for approximately 52 weeks with 8 weeks of follow-up in the Base Study. A subset of participants will also receive a second implant for an additional 12 weeks before 8 weeks of follow-up in the Substudy.

Official Title
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A Phase 2a, Double-Blind, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of a Radiopaque Matrix MK-8591 Implant in Participants at Low-Risk for HIV-1 Infection

Conditions
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Human Immunodeficiency Virus, HIV

Intervention / Treatment
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* Drug: Islatravir
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Is in good health Is confirmed human immunodeficiency virus (HIV)-uninfected Is at low risk of HIV infection For males, uses contraception in accordance with local regulations regarding contraception use for those participating in clinical trials For females, is not pregnant or breastfeeding and one of the following applies: Is not a participant of childbearing potential (POCBP) Is a POCBP and uses an acceptable contraception method or is abstinent Exclusion Criteria: Has an active diagnosis of hepatitis (B or C) due to any cause Has a history of malignancy ≤5 years before signing informed consent Has a history or current evidence of any condition that might confound study results or interfere with study participation Has a history of keloid in upper arm or presence of tattoo, scar, or other physical finding that could interfere with implant placement (the contralateral arm may be used if the findings are limited to 1 arm) Is taking or is expected to take immunosuppressants during the study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Islatravir 47 mg<br>Participants receive an ISL 47 mg implant for approximately 52 weeks. A subset of participants will receive a second implant for 12 weeks after removal of the first implant. | Drug: Islatravir<br>* ISL 47, 52, or 57 mg implantable rod placed subdermally on the upper arm.<br>* Other names: MK-8591;|
| Experimental: Islatravir 52 mg<br>Participants receive an ISL 52 mg implant for approximately 52 weeks. A subset of participants will receive a second implant for 12 weeks after removal of the first implant. | Drug: Islatravir<br>* ISL 47, 52, or 57 mg implantable rod placed subdermally on the upper arm.<br>* Other names: MK-8591;|
| Experimental: Islatravir 57 mg<br>Participants receive an ISL 57 mg implant for approximately 52 weeks. A subset of participants will receive a second implant for 12 weeks after removal of the first implant. | Drug: Islatravir<br>* ISL 47, 52, or 57 mg implantable rod placed subdermally on the upper arm.<br>* Other names: MK-8591;|
| Placebo Comparator: Placebo<br>Participants receive a placebo implant for approximately 52 weeks. A subset of participants will receive a second implant for 12 weeks after removal of the first implant. | Drug: Placebo<br>* Placebo implantable rod placed subdermally on the upper arm.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of participants with ≥1 adverse events (AEs) | 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. | Up to 60 weeks | 
| Percentage of participants withdrawing from study treatment due to 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. | Up to 52 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma concentration of islatravir (ISL) 12 weeks after placement of an ISL-eluting implant (ISL C12weeks) | Plasma ISL C12weeks will be determined. | Week 12 | 
| Plasma concentration of islatravir (ISL) 52 weeks after placement of an ISL-eluting implant (ISL C52weeks) | Plasma ISL C52weeks will be determined. | Week 52 |