The primary purpose of the study is to investigate safety and tolerability following single and multiple ascending subcutaneous (SC) and intramuscular (IM) doses of capsid inhibitors in healthy participants. The study will also describe the pharmacokinetics following single and multiple ascending SC and IM doses of capsid inhibitors in healthy participants.

Inclusion Criteria:

• Participants who are overtly healthy.
• Participants who are negative on a single test for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) (approved molecular polymerase chain reaction (PCR), point of care test), performed on the day of admission (Day -1). A negative result is required prior to the administration of study intervention on Day 1.
• Male or female participants of non-childbearing potential.
• Capable of giving signed informed consent.

Exclusion Criteria:

• History or presence of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, neurological or psychiatric disorders capable of significantly altering the absorption, metabolism, or elimination of drugs; constituting a risk when taking the study intervention or interfering with the interpretation of data.
• Abnormal blood pressure.
• Lymphoma, leukemia, or any malignancy within the past 5 years except for basal cell or squamous epithelial carcinomas of the skin that have been resected with no evidence of metastatic disease for 3 years.
• Breast cancer within the past 10 years.
• Current or chronic history of liver disease or known hepatic or biliary abnormalities.
• History of sensitivity to any of the study interventions, a history of drug allergy or other allergy that contraindicates their participation.
• The participant has an underlying skin disease or disorder that would interfere with assessment of injection sites.
• Participants considered to have insufficient musculature to allow safe capsid inhibitor intramuscular (gluteus medius) administration.
• History of or on-going high-risk behaviours that may put the participant at increased risk for HIV.
• Past or intended use of over-the-counter or prescription medication including herbal medications.
• Current enrollment or recent past participation in another investigational study.
• Exposure to more than 4 investigational products within 12 months prior to dosing.
• Alanine transaminase (ALT) ≥1.5x upper limit of normal (ULN), Total bilirubin ≥1.5x ULN (isolated total bilirubin >1.5xULN), and/or estimated creatinine clearance (eGFR) of <60 millilitre per minute (mL/min)/1.73 square meter (m^2).
• History of or current infection with hepatitis B or hepatitis C.
• Positive SARS-CoV-2 polymerase chain reaction test, having signs and symptoms, or having contact with known coronavirus disease 2019 (COVID-19) positive person/s in the 14 days prior to inpatient admission.
• Use of tobacco or nicotine-containing products, regular alcohol consumption and/or regular use of known drugs of abuse.
• Positive HIV antibody/antigen test.
• Abnormal electrocardiogram (ECG) parameters.
• Evidence of previous myocardial infarction, any conduction abnormality, any significant arrhythmia, non-sustained or sustained ventricular tachycardia, and/or sinus pauses (>3 seconds).
• The participant has a tattoo or other dermatological condition overlying the location of injection or a prior history of silicone implants or fillers (gluteal) which may interfere with interpretation of injection site reactions or administration of study product.

Sponsor will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.viiv-studyregister.com/documents/About\_ViiV\_Patient\_Level\_Data\_Sharing\_Final\_25Sep2023.pdf.

Anonymized IPD will be made available within 6 months of publication of primary, key secondary and safety results for studies in product with approved indication(s) or terminated asset(s) across all indications.

Anonymized IPD is shared with researchers whose proposals are approved by an Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months but an extension may be granted, when justified, for up to 6 months.