Independently, in 2022 the priMe project completed recruitment into its phase III trial of VPM1002. Like BCG, VPM1002 is based on a relative of Mtb, M. bovis, which causes bovine TB, but has been precisely engineered so that it retains some of the immune-stimulating components that have been lost in BCG. The priMe trial is being carried out in Gabon, Kenya, South Africa, Tanzania and Uganda, with VPM1002 also being compared with BCG.

The POR-TB trial is assessing an innovative use of vaccination against TB – prevention of recurrence (POR). It is evaluating a novel vaccine, H56:IC31, which is designed to prevent latent Mtb infections from progressing to active TB disease. To assess its efficacy, POR-TB trial is undertaking a prevention of recurrence study, to determine whether it reduces the number of patients who relapse after completion of TB antibiotic treatment – relapse is typically seen in about 1 in 10 patients. This will provide an efficient trial design to determine whether larger-scale efficacy studies are warranted. Dosing of the final participant in the POR-TB trial took place in March 2022.

In May 2022, the MTBVACN3 project held its kick-off meeting in Spain. This phase III trial is evaluating a live attenuated Mycobacterium tuberculosis (Mtb) vaccine, MTBVAC, as a potential alternative or complement to the childhood vaccine BCG. It aims to recruit more than 7000 newborns at six sites in TB-endemic countries in sub-Saharan Africa, with participants being randomised to receive either MTBVAC or BCG.

The MTBVACN3 project is drawing on the related MTBVAC-Newborns trial, a phase IIa dose-escalation study which completed recruitment in 2021. This work identified the dose being evaluated in the MTBVACN3 project.

Although affected by the COVID-19 pandemic, the projects have continued to make progress. EDCTP, TBVI and the individual projects are exploring opportunities for collaboration, including on the development of new resources for the TB vaccine R&D community, building on those made available on the EDCTP website in 2021; these included various guidance documents and templates, as well as a directory of TB vaccine trial sites in Africa. 

EDCTP has invested more than €50 million in four TB vaccine projects, focusing on prevention of infection in newborns (MTBVACN3, MTBVAC-Newborns, priMe) and prevention of recurrence in adults treated for TB disease (POR-TB). In April 2022, representatives of these projects met to exchange knowledge and experiences, at an event organised by the Tuberculosis Vaccine Initiative (TBVI), which has received funding from EDCTP to promote coordination across projects.