A Study to Investigate the Antiviral Effect, Safety, Tolerability and Pharmacokinetics of VH3739937 in in Treatment-Naive Adults Living With HIV-1

Inclusion Criteria: Participants who are overtly healthy (other than HIV infection) as determined by the Investigator or medically qualified designee based on a medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring Positive HIV antibody test Treatment-naïve: No Antiretrovirals (ARVs) (in combination or monotherapy) received after the diagnosis of HIV-1 infection Body weight ≥50.0 kilogram (kg) (110 pounds [lbs]) for men and ≥45.0 kg (99 lbs) for women and BMI for all participants within the range 18.5-35.0 kilogram per meter square (kg/m^2). Capable of giving signed informed consent Participant must be willing and able to start Combination Antiretrovial Therapy (cART) as selected with the Investigator on Study Day 8 (except in the case of early termination, clinically relevant AE/SAE, lab abnormality, the withdrawal of consent, lost to follow-up, etc., where circumstances could dictate otherwise). Exclusion Criteria: Current or chronic history of liver disease or known hepatic or biliary abnormalities (with the exception of Gilbert's syndrome or asymptomatic gallstones) Participants with primary HIV infection, evidenced by acute retroviral syndrome (e.g., fever, malaise, fatigue, etc) and/or evidence of recent (within 3 months) documented viremia without antibody production and/or evidence of recent (within 3 months) documented seroconversion Myocardial infarction, acute coronary syndrome, unstable angina, stroke, transient ischemic attack, or intermittent claudication in the past 3 months The participant has received an investigational HIV vaccine (immunotherapeutic or immunomodulatory) Regular use of drugs of abuse Sensitivity to heparin or heparin-induced thrombocytopenia