ACTTIVAC

The challenge

Tuberculosis (TB) remains one of the world’s biggest public health challenges, with an estimated 10 million new cases a year. Transmission of TB is mostly due to infections in adolescents and adults, who are therefore a critical target group for new vaccine development.

TB vaccine development has proven highly challenging. The exact nature of protective immunity remains unclear: T-cell responses (particularly Th1-type responses) appear to be critical but are not by themselves a guarantee of protection. Relatively few vaccine candidates are in the pipeline, and there is a high risk of failure, so there is a continuing need to advance potential new options. The ACTTIVAC project is focusing on a highly promising TB vaccine candidate, ID93+GLA-SE, developed by the Access to Advanced Health Institute (AAHI). ID93+GLA-SE is a protein subunit vaccine that incorporates four TB antigens associated with virulence or disease, as well as an adjuvant (GLA-SE) designed to enhance immune responses against vaccine antigens.

The project

A key innovation in the ACTTIVAC project is the transition to a single-vial lyophilised (freeze-dried) formulation of the ID93+GLA-SE vaccine. Unlike the earlier two-vial liquid version, the single-vial presentation simplifies preparation and administration, reduces the risk of dosing errors, and streamlines supply chain logistics. These are critical advantages for large-scale immunisation programmes. Critically, the thermostable formulation remains stable at higher ambient temperatures, eliminating or greatly reducing dependence on a cold chain/refrigeration storage. This enables reliable delivery to remote, hard-to-reach, or hot-climate settings across sub-Saharan Africa and other resource-limited regions, where maintaining refrigeration is often challenging and costly. Together, these improvements significantly enhance the vaccine’s practicality, accessibility, and potential for rapid rollout in TB-endemic countries.

AAHI’s agreement to the technology transfer of ID93+GLA-SE adjuvant manufacturing to African partners such as Afrigen Biologics represents a strategic step toward greater health sovereignty on the continent. By enabling local production of this critical vaccine, often one of the most complex and expensive elements, the initiative reduces reliance on distant global supply chains, mitigates risks of shortages or delays, and can lower long-term costs. 

Beyond ID93+GLA-SE, this capacity-building effort strengthens Africa’s overall vaccine manufacturing ecosystem, fosters skills development and technology ownership, and positions the continent to better respond to future health threats with home-grown solutions rather than depending on imports. This collaborative approach not only accelerates access to the current TB vaccine candidate but also lays a foundation for sustainable, regionally controlled vaccine production. This same principle extends to the trial's data: BioInformatiCo will manage the study's clinical data to regulatory standards, keeping regulatory-grade research data and the capacity to produce it on the continent.

The ACTTIVAC project, coordinated by Stichting Tuberculosis Vaccine Initiative, is a phase 2a clinical trial of this new formulation, with the main goal of selecting a suitable dose and administration regimen for a future phase 2b efficacy trial. Safety and immunogenicity of four different doses will be evaluated at two ethnically and geographically diverse sites in South Africa, led by the South African Tuberculosis Vaccine Initiative of the University of Cape Town and the Aurum Institute, focusing on BCG-vaccinated, TB-exposed adolescents and adults. 

In addition to antibody and T-cell responses, the study will assess a wide range of other immune responses that might be associated with long-term protection against TB disease. The thermostability properties of the new formulation will also be evaluated in field conditions by Obafemi Awolowo University at sites in Nigeria.

Impact

The ACTTIVAC project will advance a much-needed new vaccine for tuberculosis by:

• Generating safety and immunogenicity data for the new thermostable, lyophilised formulation of ID93+GLA-SE in TB-endemic populations in sub-Saharan Africa.
• Identifying the optimal dose of ID93+GLA-SE for a subsequent field efficacy trial.
• Establishing the foundation for local manufacturing of the GLA-SE adjuvant in Africa, strengthening regional production capabilities.
• Advancing AAHI’s shark-free squalene, which is a plant-based Solanesol rather than shark liver oil, supporting ethical sourcing, scalable manufacturing and a more resilient supply chain in Africa.

With an effective TB vaccine urgently needed, the ACTTIVAC project’s work on ID93+GLA-SE will bring a promising candidate closer to crucial field testing to assess its efficacy and potential impact on TB control.