The CHAPS Trial: Combined HIV Adolescent PrEP and Prevention (CHAPS)
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ClinicalTrials.gov Identifier: NCT03986970 |
Recruitment Status :
Completed
First Posted : June 14, 2019
Last Update Posted : August 2, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
HIV/AIDS | Drug: Tenofovir | Phase 2 |
- Investigate the timing and dose of FTC-TDF and FTC-TAF as oral PrEP and in vitro PEP (applied directly to removed foreskin tissue) required to prevent ex vivo HIV infection in foreskin tissue and blood using the explant model
- Determine blood, rectal fluid and foreskin tissue concentrations of FTC, TFV, TAF and their active metabolites that are required for ex vivo HIV protection
- Evaluate inflammation, cellular activation, foreskin mucosal integrity, gene expression and microbiome in foreskin tissue following oral in vivo PrEP and in vitro PEP
- Evaluate the efficacy of in vitro post exposure dosing with PrEP in protection against ex vivo HIV infection using the explant model
- To investigate sexual behaviour, PrEP acceptability and feedback on HIV prevention trials implementation
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 72 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | Open-label, randomised controlled trial (RCT) |
Masking: | None (Open Label) |
Primary Purpose: | Prevention |
Official Title: | Combined HIV Adolescent PrEP and Prevention: On Demand Pre-exposure Prophylaxis to Provide Protection From HIV in Men - Using Foreskin Tissue to Estimate Protection (Phase II) |
Actual Study Start Date : | November 11, 2019 |
Actual Primary Completion Date : | February 25, 2021 |
Actual Study Completion Date : | February 25, 2021 |

Arm | Intervention/treatment |
---|---|
No Intervention: Arm 1: Control
No PrEP.
|
|
Experimental: Arm 2: FTC-TDF
FTC-TDF one day, 5 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 3: FTC-TDF
FTC-TDF one day, 21 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 4: FTC-TDF
FTC-TDF two days, 5 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 5: FTC-TDF
FTC-TDF two days, 21 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 6: FTC-TAF
FTC-TAF one day, 5 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 7: FTC-TAF
FTC-TAF one day, 21 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 8: FTC-TAF
FTC-TAF two days, 5 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
Experimental: Arm 9: FTC-TAF
FTC-TAF two days, 21 hours before circumcision.
|
Drug: Tenofovir
Pre-exposure prophylaxis
Other Name: Emtricitabine, Tenofovir disoproxil, Tenofovir alafenamide |
- HIV Infection free [ Time Frame: 15 days ]We will ascertain the proportion of patients' foreskin tissue that is not infected with HIV 15 days following our ex-vivo HIV challenge. We will use the concentration of p24 antigen (pg/mL) at day15 and also report the slope of the p24 curves from day 3 to 15 (pg/mL per day) and also the AUC day 3 to 15 (pg/mL days).
- Timing [ Time Frame: 1 year ]The delay between the timing of last dose of FTC-TDF and FTC-TAF as oral PrEP and the timing of circumcision.
- Dose [ Time Frame: 1 year ]The efficacy of preventing in-vitro HIV infection by dose of FTC-TDF and FTC-TAF as oral PrEP compared to no intervention
- Blood PrEP Concentrations [ Time Frame: 1 year ]Plasma concentrations (ng/mL) of FTC, TFV, TAF and their active metabolites that are required for ex vivo HIV protection.
- Rectal Fluid PrEP concentrations [ Time Frame: 1 year ]Rectal fluid concentrations (ng/mL) of FTC, TFV, TAF and their active metabolites that are required for ex vivo HIV protection.
- Foreskin tissue PrEP concentration [ Time Frame: 1 year ]Foreskin tissue concentrations (ng/mL) of FTC, TFV, TAF and their active metabolites that are required for ex vivo HIV protection
- Efficacy of post-exposure PrEP [ Time Frame: 1 year ]The proportion of participants' foreskin tissue that remains HIV infection free in the ex-vivo challenge model when additional doses of PrEP are added to that model.

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Ages Eligible for Study: | 13 Years to 24 Years (Child, Adult) |
Sexes Eligible for Study: | Male |
Gender Based Eligibility: | Yes |
Gender Eligibility Description: | Male genital anatomical features. |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
Participants must satisfy all the following criteria within 21 days prior to their circumcision visit:
- Clinically eligible for either forceps guided, or dorsal slit circumcision
- The ability to understand and sign a written informed consent form by participant (and participant's legal guardian if younger than 18 years) prior to participation in any study procedures and to comply with all trial requirements
- Male sex at birth
- Age 13- 24 years
- Haemoglobin >9g/dL
- Weight >35Kg
- Two negative rapid HIV antibody tests results (manufactured by different companies), dating from 21 days or less prior to VMMC
- Two locator information details (including physical address, telephone contacts, email) for contacting of either patient or their parent
Exclusion Criteria:
- Any significant acute or chronic medical illness and current therapy that in the opinion of the site investigator would preclude receipt either of investigational products, or VMMC
- Any evidence that participant is not suitable for VMMC

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03986970
South Africa | |
The Perinatal HIV Research Unit | |
Johannesburg, Gauteng, South Africa, 1862 |
Principal Investigator: | Neil A Martinson | Perinatal HIV Research Unit |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Wits Health Consortium (Pty) Ltd |
ClinicalTrials.gov Identifier: | NCT03986970 |
Other Study ID Numbers: |
The CHAPS Trial |
First Posted: | June 14, 2019 Key Record Dates |
Last Update Posted: | August 2, 2022 |
Last Verified: | April 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Undecided |
Plan Description: | Data will be shared with callaborators. |
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 |
Pre-exposure prophylaxis |
Acquired Immunodeficiency Syndrome HIV Infections Blood-Borne Infections Communicable Diseases Infections Sexually Transmitted Diseases, Viral Sexually Transmitted Diseases Lentivirus Infections Retroviridae Infections RNA Virus Infections Virus Diseases Slow Virus Diseases |
Immunologic Deficiency Syndromes Immune System Diseases Tenofovir Emtricitabine Antiviral Agents Anti-Infective Agents Reverse Transcriptase Inhibitors Nucleic Acid Synthesis Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Anti-HIV Agents Anti-Retroviral Agents |