The M72 could potentially become the first new vaccine to help prevent pulmonary TB, a form of active TB, in more than 100 years if it is proven effective.

To support the M72 Phase III clinical trial, which will cost an estimated US$550 million, Wellcome is providing up to $150 million while the Gates Foundation will fund the remainder, about $400 million.

As TB remains one of the world’s deadliest infectious diseases, the development of an affordable and accessible vaccine for adolescents and adults is considered an innovative approach desperately needed to drive up progress in preventing escalating infections and in protecting those most affected.

“People can be infected [with a bacterium that causes TB] but they do not have the signs of infection and do not have TB disease. By vaccinating them, we can prevent their infection from progressing to active TB disease. It will ultimately drive down the disease transmission,” said Wellcome infectious diseases director Alexander Pym in a virtual press briefing about TB on Wednesday.

He asserted the funding of the M72 vaccine as a potential new tool in TB prevention, and control could accelerate efforts to eliminate TB as a public health threat.

In 2021, about 10.6 million people suffered from TB with 1.6 million deaths, about 4,300 people per day, according to World Health Organization (WHO) data. Almost a quarter of today’s global population is believed to have latent TB, in which TB bacteria stay in the body without making them sick.

During the COVID-19 pandemic in 2021, TB cases increased by 4.5 percent from those reported in 2020, and because of virus-related mobility restrictions, fewer people were diagnosed or received treatment.

Read also: Do not overlook threat of TB during COVID-19 pandemic, says Jokowi

TB tends to heavily impact people in low- and middle-income countries. People at highest risk are often living in poverty, in which they have poor living and working conditions and suffer from undernutrition.

“TB is a disease of poverty. It remains rife in many middle-income countries, even in the richer regions of the world […]. And COVID-19 has given us all the sense that there are no national barriers that you can hide behind for a global transmission problem like TB,” said Trevor Mundel, president of Global Health at the Gates Foundation, in the press briefing.

As of today, Bacille Calmette-Guérin (BCG) remains the only TB vaccine in use after it was first administered to people in 1921. The vaccine helps protect babies and young children against severe systemic forms of TB. However, it offers only limited protection against pulmonary TB among adolescents and adults.

“The M72 vaccine candidate is developed to give adolescents and adults stronger protection against pulmonary TB. But one point I need to underline here, the M72 vaccine will not be used to replace BCG vaccinations in children,” Pym told The Jakarta Post.

The Bill & Melinda Gates Medical Research Institute (the Gates MRI), a nonprofit organization and subsidiary of the Gates Foundation, will sponsor the Phase III clinical trial to assess the efficacy of the M72 vaccine in preventing progression from latent TB infection to pulmonary TB.

Conducted in collaboration with an international consortium of TB clinical investigators, the trial will enroll approximately 26,000 people, including people living with HIV and without TB infection, at more than 50 trial sites in Africa and Southeast Asia. The Gates MRI is the license holder for the M72 in low- and middle-income countries with a high TB burden.

Read also: Govt scales up TB surveillance as caseload rises after COVID-19

Africa Health Research Institute head of public engagement Nomathamsanqa Majozi said despite being curable, TB remains one of the leading causes of death in South Africa.

According to Majozi, in the area where she lives and works, more than half of all people have had, or will have, TB at some point in their lives. The consequences are devastating, both at a personal and a community level, she added

“From me, I’m quite excited about the possibility for us to have a new TB vaccine. Our aim should be a zero rate of TB because this disease is curable and preventable. If we can get a vaccine that is effective, then there’s a hope that our communities will be healthy,” said Majozi.

“The M72 offers us new hope for a TB-free future,” she said in the press briefing.

The M72/AS01E vaccine candidate is one of 17 TB vaccine candidates currently in the pipeline and it has been in development since the early 2000s. The vaccine candidate contains the M72 recombinant fusion protein, which is derived from two Mycobacterium tuberculosis antigens (Mtb32A and Mtb39A), combined with the GSK proprietary Adjuvant System AS01E.

GSK developed the M72 vaccine candidate up to the proof-of-concept phase (Phase IIb) under its partnership with Aeras and the International AIDS Vaccine Initiative (IAVI), with a partial funding from the Gates Foundation.

In the Phase IIb trial, the M72 showed approximately 50 percent efficacy in reducing pulmonary TB in adults with latent TB infection.

“With TB cases and deaths on the rise, the need for new tools has never been more urgent,” said Bill Gates, cochair of the Bill & Melinda Gates Foundation, in a statement.

“Greater investment in safe and effective TB vaccines alongside a suite of new diagnostics and treatment could transform TB care for millions of people, saving lives and lowering the burden of this devastating and costly disease.”

To achieve the 2030 Sustainable Development Goals (SDGs) target of an 80 percent reduction in the TB incidence rate compared with 2015, the world needs new tools to combat the disease, the United Nations says.

“The tuberculosis crisis demands a new vaccine to reduce disease transmission and avoidable deaths, especially targeting adults and adolescents who carry at least 90 percent of the TB epidemic’s burden,” said WHO director general Tedros Adhanom Ghebreyesus in a statement.