Treezer Michelle Atieno
There is evidence that giving infants the BCG vaccine helps protect them from serious forms of Tuberculosis (TB) when they’re young, like miliary TB or TB meningitis. But as they grow up, the vaccine doesn’t work as well against the most common type of TB in older kids and adults, called pulmonary TB.
In South Africa, TB rates have been reducing slowly since 2010, but they are still high. In a recent interview with Zameer Brey, the Interim Director for Technology Diffusion at the Bill and Melinda Gates Foundation, he described TB as stubbornly high in South Africa.
Zameer stated, “The number of South Africans dying from tuberculosis every day is equivalent to a plane full of people crashing and killing South Africans daily. Just imagine if a plane actually crashed today. I’m sure the president would call for an inquiry. If it happened the next day, we would probably see the airspace being closed.”
“However, tuberculosis is a disease that disproportionately affects the poor. Even after 100 years, there is still no better vaccine than the old BCG, which has limited efficacy and only protects certain age groups.”
According to the World Health Organization, TB claimed the lives of approximately 1 in 8 people diagnosed with the disease in 2022, resulting in over 3,500 deaths worldwide each day. In South Africa alone, about 280,000 individuals are diagnosed with TB each year.
In response to this development, on March 19th, the Gates MRI announced the start of a Phase 3 clinical trial for the M72/AS01E tuberculosis vaccine candidate. The initial doses have been administered in South Africa, where TB is widespread. If proven safe and effective, this vaccine could be a significant breakthrough in preventing pulmonary TB in adolescents and adults, marking the first of its kind in over a century.
During a media roundtable with the President of Global Health at the Bill & Melinda Gates Foundation Trevor Mundel on March 26th, 2024, he stated that TB affects individuals in low- and middle-income countries, particularly those living in poverty and facing adverse living and working conditions, as well as malnutrition. He expressed the organization’s commitment to combating diseases like TB in these countries through medical innovation.
“Although the clinical study of the vaccine will span several years, we are optimistic about its potential, as are our partners involved in the trial conducted in South Africa and other study sites,” said Trevor.
The vaccine candidate’s development originally started in the early 2000s. The biopharma company GSK, in collaboration with Aeras and IAVI, designed and evaluated the vaccine up to Phase 2b. GSK primarily funded the development, with some funding from the Gates Foundation. In 2020, GSK partnered with the Gates MRI to further advance the vaccine.GSK still provides technical assistance and supplies the adjuvant component of the vaccine for the Phase 3 trial. They also plan to continue supplying it after licensing if the trial is successful.
“All the partners involved in the trial are focused on ensuring the long-term accessibility and affordability of the vaccine for communities with a high disease burden, such as South Africa,” said Trevor. “The Gates MRI, along with GSK, Wellcome, and the Gates Foundation, is collaborating to guide the TB candidate vaccine through Phase 3. Their aim is to understand the demand for the vaccine and create a plan for long-term access if the trial is successful.”
According to Trevor, this involves supporting research, collecting evidence on the vaccine’s impact, identifying community requirements for vaccine acceptance, and collaborating with necessary partners for vaccine implementation. Additionally, the trial funders plan to form an international advisory group. Developing and ensuring access to global health products requires global collaboration and partnerships.
A press release by the Gates Foundation explains that the trial will involve a maximum of 20,000 participants at trial sites across seven countries. Participants will be randomly assigned to receive either the M72/AS01E investigational vaccine or a placebo in a double-blind manner. This approach is standard for assessing the safety and effectiveness of an investigational vaccine.
“We are ecstatic that the Phase 3 trial is now underway after dedicating more than two decades to developing this crucial candidate vaccine,” said Deborah Waterhouse, CEO of ViiV Healthcare and President of Global Health at GSK. “Our partnership demonstrates the potential of leveraging diverse expertise to address challenging diseases like TB.”
Tuberculosis (TB) is a deadly infectious disease globally and the leading cause of death for individuals with HIV. However, the only available TB vaccine, BCG, was developed in 1921. While it provides protection against severe forms of TB in infants and young children, it does not offer sufficient protection against the pulmonary form of the disease in adolescents and adults, which is responsible for the transmission of the TB bacteria.
“If M72/AS01E proves effective, it could inject new life into the global fight against TB, which has been hindered by the COVID-19 pandemic,” said Alemnew Dagnew, M.D., leader of the M72/AS01E development at the Gates MRI. “As a physician who has worked in Ethiopia, I have witnessed the devastating impact of pulmonary TB on communities. A vaccine that can help prevent this would be transformative.” Dagnew emphasized that TB is not only a health issue but also a socio-economic one, as it affects individuals during their productive years and leads to a loss of income for families.
“We need to take immediate action in developing and distributing innovative tools that can revolutionize the prevention, diagnosis, and treatment of TB. The Phase 3 clinical trial for the M72 TB vaccine candidate by Gates MRI marks a significant milestone in the battle against TB, a disease that wreaks havoc on vulnerable communities. We view this trial as the beginning of a series of opportunities that will bring forth promising new TB tools. The Gates Foundation is dedicated to supporting partners in expediting the solutions necessary to save lives and alleviate suffering caused by this preventable illness,” expressed Trevor.
Alex Pym, Director of Infectious Disease at Wellcome, said, “While achieving results will require a long journey, the initiation of this trial in South Africa brings us one step closer to having an effective vaccine to safeguard those individuals most susceptible to TB. Collaboration with regulators, policymakers, and affected communities on a global scale is vital to ensure that those in greatest need can benefit from this vaccine, provided the trial proves successful.”
The trial is expected to take up to five years to complete, followed by data analysis and preparation for submission to regulatory authorities.
“After a century of battling TB, the exciting news is finally here. This trial, sponsored by the Gates Foundation, is a $500 million endeavour. Our goal is to develop a vaccine to prevent tuberculosis infection and transmission, primarily benefiting the poor and reducing inequality. This is an excellent example of how the foundation steps in where the market fails to produce a vaccine,” said Zameer.
“Although it will be costly and require a long-term approach, we believe that the foundation’s investments in over a dozen vaccines in the last 20 years have played a catalytic role in reaching this point.”
