A multi-country program evaluation (Opt4TPT)

Optimising the delivery cascade for tuberculosis preventive treatment among people living with HIV

The Opt4TPT study is a three-year programmatic assessment of TPT delivery across three countries, namely Ethiopia, South Africa and Zimbabwe, to generate critical knowledge to improve TPT uptake, implementation and outcomes. Specifically, the objectives of the study are to →

Quantify the TPT continuum of care

Identify Models of Care

Conduct a cost-effectiveness analysis

Updated October 2021

Project Milestones

Zimbabwe study team initiates patients on TB preventive treatment (TPT)

From 17 August 2021, the Opt4TPT Study team in Zimbabwe led by the Clinton Health Access Initiative (CHAI) started enrolling patients initiating on 3HP, a short course TB preventive treatment or Isoniazid prevention treatment (IPT) at three public health facilities.

On 16 September 2021, the Opt4TPT study team in South Africa implemented by the Aurum Institute started enrolling patients visiting the Chiawelo Community Health Centre (CHC) for ART refills and initiations at one of the three study sites.



The Ethiopian Opt4TPT team starts to recruit and enrol participants in study

The Ethiopian team of Opt4TPT, a three-year programmatic assessment of Tuberculosis Preventive Treatment (TPT) delivery, started enrolment of participants on 25 August 2021, at Arada Health Centre. As of 13 January 2022, 667 participants have been enrolled.



How will data be collected?

Patient Level


A prospective observational study will be conducted at three health facilities per country—two implementing 3HP and one still implementing IPT. Adult patients receiving HIV care will be offered an opportunity to take part in the study at the time of antiretroviral therapy (ART) initiation or refill until 200 eligible and consenting participants are enrolled at each participating facility.

Clinic Level

To understand structures and processes in the delivery of TPT, data will be collected across 10 clinics in each of the project countries by observing and analysing all steps involved for individual patients.

This will include reviewing patient records, audio recordings of clinician and patient encounters, pharmacy records and interviews with pharmacy managers to assess the drug stock management and provider barriers and facilitators to prescribing TPT.


The Opt4TPT project will build on existing projects and global investments. This includes the Aurum Institute’s IMPAACT4TB project, which is catalysing the initiation of 3HP among approximately 2 million people, focusing on PLHIV and children under five, and subsequently all those in close contact with TB patients in 12 high-burden countries.1 IMPAACT4TB is seeking to inform the feasibility of introducing 3HP from global pricing, national policy and clinic roll-out perspectives. The project’s monitoring and evaluation is not, however, designed to assess clinic level processes, provider attitudes, the patient journey (including costs) or TB drug resistance in 3HP clinics. Therefore, Opt4TPT will build on the IMPAACT4TB infrastructure to gain deeper insights into patient-level and clinic-level processes, experiences and preferences for TPT regimens.


By following a cohort of PLHIV prospectively and directly observing service delivery in health facilities, Opt4TPT’s approach will provide valuable new knowledge regarding routine use of TPT, as well as outcomes during, and following, TPT. This study will create an important understanding of TPT uptake and completion from the patient perspective and delivery from the health system perspective. These results will provide actionable information for improving service delivery and the scale-up of TPT.

Opt4TPT is funded by the Bill and Melinda Gates Foundation and is being implemented by the Aurum Institute, in collaboration with Johns Hopkins University School of Medicine, as well as KNCV (Ethiopia), Clinton Health Access Initiative (Zimbabwe) and Ministries of Health in project countries. The study is being implemented in collaboration with the IMPAACT4TB project.

project progress
Study Patients
TPT Adherence
Download the full information brochure here