A Study to Evaluate the Effectiveness of Long-acting (LA) Cabotegravir (CAB) + Rilpivirine (RPV) LA When Given to Participants With Detectable HIV-1

Inclusion Criteria:

• Age

1. Aged >=12 years and >=35 kg (at the time of obtaining informed consent).

• Type of Participant and Disease Characteristics 2.HIV-1 infection, documented by anylicensed rapid HIV test or HIV enzyme or chemiluminescence immunoassay (E/CIA) testkit at any time prior to study entry and confirmed by a licensed Western blot or asecond antibody test by a method other than the initial rapid HIV and/or E/CIA, orby HIV-1 antigen, plasma HIV-1 RNA VL.

3.Plasma HIV-1 RNA >1 000 c/mL and greater than (<) 100 000 c/mL at Screening. 4.Evidence of insufficient virologic response to participant's current oral ARTregimen within 18 months prior to study entry according to at least 1 of thefollowing criteria: i.<1 log10 decrease in HIV-1 RNA or HIV-1 RNA >200 c/mL at 2time points at least 4 weeks apart in individuals who have been prescribed oral ARTfor at least 3 consecutive months.

ii. Documented lapse in current oral ART regimen usage expected to result in HIV-1 viremia (defined as at least a 30-day consecutive period of non-use of oral ART) iii. Documented need for change from oral ART regimen that investigator attributes as primary reason for insufficient virologic response (e.g., safety findings and/or limited tolerability, clinically relevant DDIs).

Currently being treated with an oral ART regimen specific regimen to be recorded at Screening, and willing to continue taking that regimen until approximately 1 week after the Month 6 visit.

• Pregnancy, Sex and Contraceptive/Barrier Requirements 5. Person of childbearingpotential (POCBP) must have a negative serum or urine pregnancy test at screeningand on Day 1.

• Informed Consent/Assent 6.Informed consent/Assent must be provided as follows:

1. Adult participants (>=18 years old) must be capable of giving signed informedconsent as described in the full study protocol, which includes compliance withthe requirements and restrictions listed in the informed consent form (ICF) andstated in the full study protocol.

2. For adolescent participants (12 to <18 years of age at screening), theparent(s) or legal guardian must be capable of giving signed informed consent.

Exclusion Criteria:

• Medical Conditions

1. HIV-1 Subtype A6, if known from historical result.

2. Participants who are pregnant, breast/chest feeding or plan to become pregnant orbreast/chest feed during the study.

3. Unstable liver disease (as defined by the presence of ascites, encephalopathy,coagulopathy, hypoalbuminemia, esophageal or gastric varices, or persistentjaundice), cirrhosis, known biliary abnormalities (with the exception ofhyperbilirubinemia or jaundice due to Gilbert's syndrome or asymptomaticgallstones).

4. Individuals with both HIV and Hepatitis B virus (HBV) will be excluded fromparticipating in studies where they would not be able to receive appropriate therapyfor their HBV co-infection and therefore may be at risk of hepatitis B flare.Exclusion will be determined by evidence of HBV infection based on the results oftesting at Screening for HBsAg, HBcAb, HBsAb and HBV.

5. History of liver cirrhosis with or without hepatitis viral co-infection.

6. Participants with severe hepatic impairment (Class C) as determined by Child-Pughclassification.

7. Participants with HCV co-infection will be excluded entry into this study if theyare currently receiving anti-HCV therapy at baseline (Day 1).

8. Participants determined by the investigator to have a high risk of seizures,including participants with an unstable or poorly controlled seizure disorder.

9. History of sensitivity to any of the study medications or their components or drugsof their class, or a history of drug or other allergy that, in the opinion of theinvestigator or Medical Monitor, contraindicates their participation.

10. Participants who in the investigator's judgment, pose a significant suicidalityrisk. Participant's history of suicidal behaviour and/or suicidal ideation should beconsidered when evaluating for suicide risk.

11. Any pre-existing physical or mental condition which, in the opinion of theInvestigator, may interfere with the participant's ability to comply with the dosingschedule and/or protocol evaluations or which may compromise the safety of theparticipant.

• Prior/Concomitant Therapy

12. Any previous use of CAB.

13. Current or anticipated need for chronic anti-coagulants.

14. Use of concomitant medications which are associated with Torsades de Pointes (TdP).

15. Treatment with an HIV-1 immunotherapeutic vaccine within 90 days of Screening.

16. Treatment with any of the following agents within 28 days of Screening:

17. radiation therapy;

18. cytotoxic chemotherapeutic agents;

19. tuberculosis therapy with the exception of isoniazid;

20. anti-coagulation agents, with the exception of the use of low doseacetylsalicylic acid (<=325mg);

21. immunomodulators that alter immune responses such as chronic systemiccorticosteroids, interleukins, or interferons.

22. Exposure to an experimental drug or experimental vaccine within either 28 days, 5half-lives of the test agent, or twice the duration of the biological effect of thetest agent, whichever is longer, prior to the first dose of investigationalmedicinal product (IP).

23. Participants receiving any protocol-prohibited medication and who are unwilling orunable to switch to an alternate medication.

• Prior/Concurrent Clinical Study Experience

19. Participant is currently participating in, or anticipates being selected for, anyother interventional study.

• Diagnostic assessments

20. Any evidence of viral drug resistance based on the presence of any major RAM toINSTIs or NNRTIs in the Screening result; or, if known, in any historical resistancetest result.

21. Any acute laboratory abnormality at Screening, which, in the opinion of theinvestigator, would preclude the participant's participation in the study of aninvestigational compound.

22. Any verified Grade 4 laboratory abnormality, with the exception of Grade 4 lipidabnormalities. A single repeat test is allowed during the Screening period to verifya result.

23. ALT >=5 times ULN or ALT >=3×ULN and bilirubin >=1.5×ULN (with >35% directbilirubin).

24. eGFR of <30 mL/min/1.73 m2 via refitted, race-neutral CKD-EPIcr_R method (adultparticipants) or <50 mL/min/1.73 m2 using the Bedside Schwartz equation (adolescentparticipants).

25. Hemoglobin <9.0 g/dL.

26. Corrected QT interval (QTc >450 msec or QTc >480 msec for participants with bundlebranch block, calculated using ECGs performed in triplicate).

• Other exclusions

27. Unwilling to receive injections, or unable to receive gluteal injections.

28. The participant has gluteal implants or prosthesis; or a tattoo or otherdermatological condition overlying the gluteus region which may interfere withinterpretation of injection site reaction (ISRs).

29. Evidence of alcohol or substance use disorder within the previous 12 months, usingstandard methods for their site, that would interfere with the participant's safety.

30. Adolescents who are wards of the state or government. To assess any potential impacton participant eligibility with regard to safety, the investigator must refer to theInvestigator's brochure (IB) and supplements, approved product labels, and/or localprescribing information for detailed information regarding warnings, precautions,contraindications, AEs, drug interactions, and other significant data pertaining tothe study drugs.