Single-arm, single-center, Phase I/II clinical trial, in four groups. Individuals with HIV infection taking Efavirenz (EFV) and two nucleoside reverse transcriptase inhibitors (NRTI) who have undetectable (Groups 1 and 2) or detectable (Group 3 and 4) HIV viral load and an indication for TPT, will be switched to DTG with tenofovir/emtricitabine (Groups 1 and 2) or lamivudine/tenofovir (Groups 3 and 4). Group 1 and 2 will receive weekly HP for 12 total doses starting 8 weeks after initiating DTG. Individuals who are on an existing DTG-based plus two NRTI ART regimen for at least eight weeks (and have not received efavirenz or nevirapine for at least two months) who have an undetectable HIV viral load may also participate. Individuals with HIV infection who are ART treatment naïve at any HIV viral load level and have an indication for TPT will start DTG and be enrolled to receive standard IPT (Group 3) or HP (Group 4) initiated at the same time as DTG. Group 3 and 4 will be enrolled after follow up of Group 1 and 2 has been completed.

Group 1 (n=30): The first 12 participants (Group 1A) will take dolutegravir 50 milligrams (mg) once daily (with tenofovir/emtricitabine) from Days 1-57. Semi-intensive PK sampling for dolutegravir will be performed on Day 57. Participants will continue once-daily dolutegravir and will receive once-weekly HP for 12 total doses beginning on Day 58. Semi-intensive PK sampling for dolutegravir will be performed on Day 72 (with the 3rd dose of HP) and Day 108 (following the 8th dose of HP). Trough concentrations (CT) will be measured on Days 59, 74, and 78. PK assessments will be performed at weeks 9 and 11 for rifapentine and at week 11 for isoniazid. VL will be measured at baseline and weeks 11 and 24. Safety labs (complete blood count (CBC), urea and electrolytes (U&E) and creatinine and liver function tests (LFT)) will be obtained at baseline, and weeks 9, 11, 13, 16, 20 and 24.

After the 12 Group 1A participants have completed the second semi-intensive PK visit, an interim PK, safety, and VL assessment will be performed to ensure that the 50 mg once daily dose is safe and meets PK targets. The subsequent 18 participants in Group 1 (Group 1B) will receive either dolutegravir 50 mg or a higher dose of dolutegravir, if dose adjustment is required (e.g. dolutegravir 50 mg twice daily just on HP dosing days, dolutegravir 50 mg twice daily seven days a week, etc.) A second interim evaluation focused on PK will occur after all Group 1B participants have completed the Week 11 semi-intensive PK visit. This evaluation will include all PK data from Group 1A, who will have completed their Week 16 semi-intensive PK visit plus PK data from Group 1B up to and including the Week 11 semi-intensive PK visit.

A third interim evaluation focused on safety and virologic response will occur after all participants (Groups 1A, 1B, and 2) have completed the Week 11 visit. This evaluation will include all safety data and HIV viral load information collected up until that point from all participants.

Group 2 (n=30): These participants will receive dolutegravir and HP at the same doses and dose schedule as the participants in Group 1B. They will undergo safety assessments at baseline and weeks 9, 11, 13, 16, 20 and 24; HIV VL assessments will be performed at baseline and weeks 11 and 24. Sparse (trough) PK samples for dolutegravir will be collected on two occasions.

Group 3 (n=25): The next 25 participants who are ART treatment naïve will start dolutegravir 50 milligrams (mg) once daily (with tenofovir/lamivudine on study Day 0. Sparse PK sampling for trough concentrations (CT) of dolutegravir will be performed on Day 1 (24 hours after taking the first dose of DTG, and before taking the first dose of standard isoniazid). Sparse PK sampling for trough concentrations (CT) of dolutegravir will be performed on Day 24 (Week 3), to parallel 721 hours after the 3rd dose of HP. The final sparse PK sampling for trough concentrations (CT) of dolutegravir will be performed on Day 59 (Week 8), to parallel 721 hours after the 8th dose of HP. HIV VL will be measured at screening, and Weeks 3, 8, 12, 16, and 24. Safety labs (complete blood count (CBC), urea and electrolytes (U&E) and creatinine and liver function tests (LFT)) will be obtained at baseline. Creatinine will be repeated at Weeks 2, 4, 8, 12, 16 and 24 and LFTs will be repeated at weeks 4, 8, and 12.

Group 4 (n=50): After Group 3 is fully enrolled, another group of 50 participants who are ART treatment naïve will start dolutegravir 50 milligrams (mg) once daily (with tenofovir/lamivudine) on Day 0. They will begin TPT with once weekly HP the day after starting DTG, on Day 1. Sparse PK sampling for trough concentrations (CT) dolutegravir will be performed on Day 1 (24 hours after the first dose of DTG, before the first dose of HP). Sparse PK sampling for trough concentrations (CT) of dolutegravir will be performed on Day 24 (721 hours after the third dose of HP). Sparse PK sampling for trough concentrations (CT) of dolutegravir will be performed on Day 59 (721 hours after the eighth dose of HP). HIV VL will be measured at screening, and Weeks 3, 8, 12, 16, and 24. Safety labs (complete blood count (CBC), urea and electrolytes (U&E) and creatinine and liver function tests (LFT)) will be obtained at baseline. Creatinine will be repeated at Weeks 2, 4, 8, 12, 16, and 24, and LFTs will be repeated at weeks 4, 8, and 12.

1 (+/- 24 hours)

Inclusion Criteria:

1. Age > 18 years
2. Weight > 50 kg
3. Documented HIV infection*
4. At least 8 weeks of HIV treatment with efavirenz or dolutegravir plus two NRTI, or ART treatment naïve, depending upon the enrolling treatment Group
5. Undetectable or detectable HIV-1 viral load, depending upon the enrolling treatment Group

Exclusion Criteria:

1. Confirmed or suspected TB disease
2. Likely to move from the study area during the study period
3. Known exposure to TB cases with known or suspected resistance to isoniazid or rifampicin in the source case
4. TB treatment within the past year
5. TB preventive therapy within the last year
6. Sensitivity or intolerance to isoniazid or rifamycins
7. On nevirapine, etravirine, rilpivirine, PI-based, or raltegravir-containing ART regimens
8. Suspected acute hepatitis or known chronic liver disease; severe hepatic impairment (Class C or greater) as determined by Child Pugh classification
9. ALT≥ 3 times the upper limit of normal (ULN)
10. Total bilirubin ≥ 2.5 times the ULN
11. Absolute neutrophil count (ANC) ≤ 750 cells/mm3
12. Creatinine clearance < 50 ml/min
13. Pregnancy or breastfeeding
14. Women of childbearing potential who are unable or unwilling to use contraception
15. Self-reported alcohol use exceeding 28 units per week for men, or 21 units for women
16. Karnofsky status < 80
17. On prohibited medications e.g. dofetilide (see Appendix 1)
18. Known porphyria

To be shared amongst the collaborators on shared database when study starts and is complete.

Results will be disseminated via conferences and publication by scientific peer reviewed journal(s)

Pre-study start: Study protocol and Informed Consent Form to collaborators on SharePoint).

Post-study completion: Clinical Study Report, Results with Statistical Analysis will be shared with scientific peer reviewed journal(s) and collaborators.

Password protected and user defined credentials (Pre-study via SharePoint)

Open access (Post-study completion)