Improving HIV-1 Control in Africa with Long Acting Antiretrovirals (IMPALA)

A Phase 3b Randomised, Multicentre, Open-label Study Evaluating the Effectiveness of Switching to Two-monthly Long-acting Injectable Cabotegravir and Rilpivirine from First-line Oral Antiretroviral Therapy in HIV-1 Positive Virologically Suppressed Adults with a History Of, or At Risk Of, Sub-optimal HIV Control in Sub-Saharan Africa

IMPALA is a randomized, open-label, multicenter, interventional study of 540 virologically suppressed HIV-1 infected adults who have a history of sub-optimal adherence to daily oral ART and/or engagement in HIV care. The study will seek to demonstrate non-inferior antiviral effectiveness of the 2-monthly long-acting injectable combination of cabotegravir/rilpivirine as compared to continuation of first line oral antiretroviral therapy.

Study Overview

• Status: Active, not recruiting
• Conditions: HIV-1-infection
• Intervention / Treatment: Drug: Cabotegravir/Rilpivirine; Drug: Antiretroviral

Detailed Description

IMPALA is a randomized, open-label, multicenter, interventional study of 540 virologically suppressed (<200 c/mL) HIV-1 infected adults (18 years or older) who have a history of sub-optimal adherence to daily oral ART and/or engagement in HIV care. IMPALA seeks to demonstrate the non-inferior antiviral effectiveness of switching to long acting injectable rilpivirine (RPV LA) plus long acting injectable cabotegravir (CAB LA) given every 2 months (Q2M CAB LA + RPV LA) by IM compared to the continuation of first-line daily oral ART containing 2 nucleoside reverse transcriptase inhibitor (NRTIs) plus an integrase strand transfer inhibitor (INSTI; dolutegravir [DTG]).

After providing written informed consent, participants will be evaluated for eligibility during the screening period. Participants who are viremic (HIV VL >200 c/mL) at the time of screening will be virologically suppressed (for >3 months) on a regimen of 2 NRTIs plus DTG prior to randomization. On Day 1 virologically suppressed (<200 c/mL for at least 3 months) individuals will be randomized 1:1 to either continue daily oral ART (2 NRTI + DTG, control arm), or switch to Q2M CAB LA + RPV LA IM, the intervention arm. Those randomized to the intervention arm will be offered either optional oral lead-in (OLI) of 1 month daily oral CAB and RPV or a direct to injection (DTI) approach. This decision to dose with or without an OLI Phase will be determined by the study participant following the informed consent discussion with the investigator. The total duration of the study will be 24 months. Any participant who has received at least a single dose of CAB LA + RPV LA and discontinues the regimen for any reason before Month 24 must start suppressive daily oral ART within 2 months of the last injection. There will be an optional real-world extension phase, provided the regimen is deemed to be non-inferior at Month 12 and 24.

• Study Type: Interventional
• Enrollment (Actual): 540
• Phase: Phase 3

Contacts and Locations

Study Locations

• Kenya
  • Kisumu, Kenya
    • Jaramogi Oginga Odinga Teaching & Referral Hospital
  • Nairobi, Kenya
    • Kenyatta National Hospital
• South Africa
  • Cape Town, South Africa
    • Desmond Tutu Health Foundation
  • Durban, South Africa
    • CAPRISA
• Uganda
  • Entebbe, Uganda
    • Entebbe Grade A Hospital
  • Fort Portal, Uganda
    • JCRC Fort Portal
  • Kampala, Uganda
    • Infectious Diseases Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. 18 years of age and above
2. HIV-1 infection confirmed in clinic records or by study team.
3. Two consecutive HIV-1 VL <200 copies/mL ≥3 months apart prior to randomization.
4. On an oral regimen of 2NRTI + DTG as part of first line ART

5. Is identified as a participant with a history of, sub-optimal ART adherence or engagement in care based on one or more of the following criteria:

   1. Documented detectable HIV-1 VL (>1000 c/mL) on all-oral ART (EFV/NVP or DTG-based) in the prior 2 years despite being ART-experienced for

      ≥3 months.

   2. History of being lost to follow-up from care (>4 weeks elapsed since a missed scheduled clinic appointment or refill in the prior 2 years).
   3. Failed to link to HIV care despite ≥3 months elapsed since HIV diagnosis.
6. Females: human chorionic gonadotrophin (HCG) negative and willing to use one highly effective form of contraception if woman of reproductive potential
7. Must sign informed consent form (ICF) indicating that the participant understands the purpose of, and procedures required for, the study and is willing to participate in the study.
8. Willing and able to attend all clinic appointments.

Exclusion Criteria:

1. Not virologically suppressed (VL<200 c/mL) for ≥3 months at the end of the screening process.
2. Previous use, or intention to use, protease inhibitor-based ART at any time.
3. Evidence of prior HIV-1 resistance test with NNRTI drug resistance mutations (other than K103N) and/or INSTI drug resistance mutations.
4. Unwillingness to receive 2 injections on a 2 monthly basis.
5. Unwilling to use a form of contraception.
6. Pregnant, breastfeeding or planning to become pregnant during the study period.
7. Requires tuberculosis therapy or other drug with clinically relevant drug interaction
8. High risk of seizures, including participants with an unstable or poorly controlled seizure disorder.
9. Has active TB or other mycobacterial disease and requires treatment.
10. Advanced liver disease, known biliary abnormalities (with the exception of Gilbert's syndrome or asymptomatic gallstones) or history of cirrhosis.
11. Chronic Hepatitis C with planned or anticipated use of Hep C therapy

12. Evidence of hepatitis B virus (HBV) infection based on the results of testing at Screening for Hepatitis B surface antigen (HBsAg), Hepatitis B core antibody (HBcAb), Hepatitis B surface antibody (HBsAb) as follows:

    • Participants positive for HBsAg are excluded
    • Participants negative for HBsAg but positive for HBcAb, with no evidence of HBsAb are excluded NOTE: Participants positive for HBcAb due to prior infection (negative HBsAg status) and with evidence of HBsAb have some immunity to HBV and have low risk of reactivation so are not excluded.
13. Current or anticipated need for chronic anticoagulation therapy.
14. Previous use of oral or injectable CAB or RPV.
15. Any Grade 4 laboratory abnormality at the conclusion of screening process.
16. Creatinine clearance (CrCl) <50 mL/min/1.732 by Chronic Kidney Disease Epidemiology Collaboration (CKD EPI) equation.
17. Alanine aminotransferase (ALT) > 3×upper limit of normal (ULN).
18. Has a tattoo or other dermatological condition overlying the gluteus region that may interfere with interpretation of ISRs.
19. Has ongoing or clinically significant medical conditions that in the opinion of the investigator may interfere with the absorption, distribution, metabolism or excretion of the study interventions or could affect participant safety.
20. Has pre-existing physical or mental condition which, in the opinion of the investigator, may interfere with the participant's ability to comply with the dosing schedule and/or protocol evaluations or which may compromise the safety of the participant.
21. Known allergies, hypersensitivity, or intolerance to cabotegravir or rilpivirine or its excipients.
22. Received an investigational intervention (including investigational vaccines) or used an invasive investigational medical device within 30 days before the planned first dose of study intervention or is currently enrolled in another interventional study.
23. Has received any prohibited medication listed in Section 6.8.2, Prohibited Medications and Non-drug Therapies and is unwilling or unable to switch to an alternate medication.

24. Has been treated with any of the following agents within 28 days of Screening:

    1. Radiation therapy.
    2. Cytotoxic chemotherapeutic agents.
    3. Tuberculosis therapy with the exception of isoniazid (isonicotinyl hydrazid, INH).
    4. Anticoagulation agents (e.g., warfarin and direct oral anticoagulants).
25. Is using immunomodulators that alter immune responses (such as chronic systemic corticosteroids, interleukins, or interferons). Note: Participants using short-term steroid tapers, topical, inhaled and intranasal corticosteroids, topical imiquimod are eligible for enrolment.
26. Treatment with an HIV-1 immunotherapeutic vaccine within 90 days of Screening.
27. QTc interval >450 ms (if QTc interval is >450 ms on the ECG read out, then it should be corrected according to Fridericia; https://www.mdcalc.com/corrected-qt-interval-qtc) within 90 days prior to study entry.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CAB LA + RPV LA Arm; The first 4 weeks of the treatment differ depending on whether participant opts for direct to injection (DTI) or Oral lead-in (OLI). DTI: participants will remain on daily oral ART for 4weeks after randomization and will receive the 1st injection of IM CAB LA 600mg+RPV LA 900mg at the Month 1 visit. 2nd injections administered at Month 2, followed by maintenance injections every 2 months (Q2M) OLI: participants will receive the study intervention in 2 phases: Participants will receive CAB 30mg+RPV 25mg OD for 4weeks to be taken daily with food. The purpose of the optional OLI Phase is to allow an opportunity for participants to assess tolerability of the combination prior to administration of the injectables. There is no proven benefit to this approach; After 4weeks participants return for the Month 1 visit to receive the 1st IM CAB LA 600mg+RPV LA 900mg injections. The 2nd injections administered at Month 2 and then continuation injections will be administered Q2M	Drug: Cabotegravir/Rilpivirine; injectable long-acting cabotegravir 600mg + long-acting rilpivirine 900mg administered every 2 months; Other Names: Vocabria/Rekambys
Active Comparator: ART Group; Participants will take a daily oral combination of 2 NRTIs plus DTG 50mg. Ideally, the single tablet fixed-dose combination regimen of (tenofovir disoproxil fumarate [TDF] 300 mg + lamivudine [3TC] 300 mg (or emtricitabine [FTC] 200 mg) + DTG 50 mg) will be used as per local country guidelines up to Month 24. If there are preexisting reasons why TDF or 3TC cannot be used as the NRTI backbone then alternative NRTIs are acceptable. Participants will be permitted to switch daily oral ART drugs in case of toxicity, after discussion with the coordinating center.	Drug: Antiretroviral; Oral antiretroviral therapy in the form of 2NRTIs + dolutegravir 50mg administered daily; Other Names: 2NRTIs + dolutegravir 50mg once daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HIV-1 viral load at 12 months	Proportion with plasma HIV-1 viral load (VL) <50 c/mL at 12 months (by Food and Drug Administration [FDA] snapshot algorithm)	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Confirmed virologic failure on 2 consecutive occasions	Proportion with confirmed virologic failure (CVF) [plasma HIV-1 VL ≥200 c/mL on 2 consecutive occasions]	12 months
Confirmed virologic failure on 2 consecutive occasions	Proportion with confirmed virologic failure (CVF) [plasma HIV-1 VL ≥200 c/mL on 2 consecutive occasions]	24 months
Lost to follow up	Proportion with LTFU [>4 weeks elapsed since their last missed appointment]	12 months
Lost to follow up	Proportion with LTFU [>4 weeks elapsed since their last missed appointment]	24 months
HIV-1 viral load <200c/mL	Proportion with plasma HIV-1 VL <200 c/mL	12 months
Change in CD4+ T cell count	Change in CD4+ T cell count from baseline	12 months
Change in CD4+ T cell count	Change in CD4+ T cell count from baseline	24 months
HIV disease progression	Incidence of HIV disease progression (HIV/AIDS related hospitalizations, illness or deaths)	24 months
Adverse Events	Incidence of adverse events (AEs)	12 months
Adverse Events	Incidence of adverse events (AEs)	24 months
Grade 3 and 4 Adverse Events	Incidence of AEs, Grade 3 and 4 excluding injection site reactions	12 months
Grade 3 and 4 Adverse Events	Incidence of AEs, Grade 3 and 4 excluding injection site reactions	24 months
Injection Site Reactions	Frequency of injection site reactions of any grade	24 months
Virologic response	Proportion with plasma HIV-1 VL <50 c/mL	12 months and 24 months
Virologic non-response	Proportion with plasma HIV-1 VL >=50 c/mL (by FDA snapshot algorithm)	24 months
Resistance Emergence	Frequency of emergence of new integrase strand transfer inhibitor and non-nucleoside reverse transcriptase inhibitor resistance mutations in those who develop virologic failure	12 months and 24 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in health-related quality of life	Change from baseline in EQ-5D-5L	12 months and 24 months
Change in health-related quality of life	Change from baseline in MOS-HIV	12 months and 24 months
Change in health-related quality of life	quality of life outcomes in in-depth interviews	6 months, 12 months and 18 months
Treatment satisfaction	For participants in the CAB LA + RPV LA group, change from baseline in HIVTSQ scores	12 months and 24 months
Treatment preference	For participants randomized to the CAB LA + RPV LA group, preference for CAB LA + RPV LA compared to daily oral ART regimen using a single dichotomous preference question	12 months and 24 months
Medical resource utilisation	medical resource utilisation	24 months
Medical resource utilisation	Clinic / hospital attendances	24 months
Medical resource utilisation	Rates of opportunistic infections and other illnesses	24 months
Programmatic acceptability of Q2M CAB LA + RPV LA	Thematic analysis of data from interviews and focus group discussions with participants, healthcare workers and key stakeholders	24 months
Treatment adherence	Self-reported adherence and pill count for daily oral ART and delayed/missed injections for CAB LA + RPV LA	24 months

Collaborators and Investigators

• Sponsor: MRC/UVRI and LSHTM Uganda Research Unit
• Collaborators: Janssen Pharmaceuticals
• Investigators: Principal Investigator: Fiona Cresswell, MBChB, PhD, MRC/UVRI & LSHTM

Study record dates

Study Major Dates

• Study Start (Actual): December 8, 2022
• Primary Completion (Estimated): April 1, 2025
• Study Completion (Estimated): March 1, 2026

Study Registration Dates

• First Submitted: September 16, 2022
• First Submitted That Met QC Criteria: September 16, 2022
• First Posted (Actual): September 19, 2022

Study Record Updates

• Last Update Posted (Actual): September 27, 2024
• Last Update Submitted That Met QC Criteria: September 25, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Molecular Mechanisms of Pharmacological Action; Anti-Infective Agents; Antiviral Agents; Reverse Transcriptase Inhibitors; Nucleic Acid Synthesis Inhibitors; Enzyme Inhibitors; Anti-HIV Agents; HIV Integrase Inhibitors; Integrase Inhibitors; Anti-Retroviral Agents; Dolutegravir; Rilpivirine; Cabotegravir
• Other Study ID Numbers: TMC278LAHTX3005

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No