The Gates Institute Pushes Forward with Tuberculosis Vaccine Trial

The Bill & Melinda Gates Medical Research Institute (Gates MRI) has announced the commencement of the third phase clinical trial evaluating the M72/AS01E tuberculosis (TB) vaccine candidate.

According to an official statement Tuesday from the foundation, the initial doses of the vaccine are administered in South Africa, where TB takes a heavy toll and should it prove to be “well-tolerated and effective,” the vaccine could potentially become the first vaccine to help prevent pulmonary TB in adolescents and adults.

It explained that the efforts could mark the first new TB vaccine in over a century to reduce the incidence of pulmonary TB, which is the most common and contagious form of the disease.

The Gates MRI noted that it will take up to five years to complete the trial, followed by data analysis and then preparation for submission of data to regulatory authorities.

The World Health Organisation estimates that 10.6 million people globally fell ill with TB while 1.3 million died in 2022. In South Africa alone, around 280,000 people are diagnosed with TB each year.

The only available TB vaccine, Bacilli Calmette-Guerin (BCG), dates back to 1921, which only protects babies and young children against severe forms of TB, but is inadequate for adolescents and adults against the pulmonary form of the disease.

Nigeria ranks first in Africa and sixth amongst 30 countries globally with the highest burden of the disease. The BCG is also the only available vaccine against tuberculosis in the country.

More about vaccine trial

According to Gates MRI, the vaccine trial will include up to 20,000 participants, including people living with HIV, at up to 60 trial sites in seven countries — South Africa, Zambia, Malawi, Mozambique, Kenya, Indonesia and Vietnam.

“Participants will receive either the investigational M72/AS01E vaccine or a placebo in what is known as a double-blind trial, meaning neither the trial participant nor the clinical investigators will know who receives vaccine or placebo,” it noted.

“This approach is considered the gold standard for evaluating the safety and efficacy of an investigational vaccine.”

The trial is being sponsored by the Gates MRI, a subsidiary of the Bill & Melinda Gates Foundation, which is supported by funding from the Gates Foundation and Wellcome.

The M72/AS01E vaccine candidate has been in development since the early 2000s. It was originally designed and clinically evaluated by the biopharma company GSK up to the proof-of-concept phase (Phase 2b), in partnership with Aeras and the International AIDS Vaccine Initiative (IAVI) and was funded by GSK and in part by the Gates Foundation.

The Gates MRI further noted that in GSK’s Phase 2b trial, M72/AS01E provided approximately 50 per cent protection against progression to active pulmonary tuberculosis for three years in Mycobacterium tuberculosis-infected HIV-negative adults, which was unprecedented in decades of TB vaccine research.

It cited that the WHO estimates that over 25 years, that level of protection could save 8.5 million lives, prevent 76 million new TB cases and save $41.5 billion for TB-affected households.

Comments from partners

The CEO of Gates MRI, Emilio Emini, was quoted to have said the launch of this pivotal Phase 3 trial demonstrates commitment to harnessing the power of medical innovation to fight diseases like TB that are particularly devastating for low- and middle-income countries.

“Clinical study of the vaccine will still require years, but our incredible partners in South Africa and elsewhere who have come together for the Phase three study share our hope in the vaccine’s potential,” he said.

Alemnew Dagnew, who leads development of M72/AS01E at the Gates MRI also said if M72/AS01E is effective, it could reinvigorate a global fight against TB that has been weakened by the COVID-19 pandemic.

Mr Dagnew noted that TB is both a health problem and a socioeconomic problem that affects people during their prime working years, leaving families without income and children without parents. Almost half of TB-affected households face costs higher than 20 per cent of their household income.