Researchers from the University of St Andrews have developed a new treatment for TB (tuberculosis) that could shorten the therapeutic process by up to two months, saving millions of lives.
TB causes almost a million deaths every year. Scientists constantly work to change this and save lives with new tools and treatments. Active treatment for TB requires a combination of drugs; the most drug-sensitive forms of the disease require at least four months of treatment using four different anti-TB drugs.
According to the World Health Organization (WHO), an estimated 1.6 million people died of TB in 2021, although some estimates have suggested that TB could have killed many more people.
Assessing multi-drug treatment
The researchers evaluated the BPaMZ regimen, consisting of bedaquiline (B), pretomanid (Pa), moxifloxacin (M), and pyrazinamide (Z). This combination of drugs has previously shown high efficacy and treatment-shortening potential in preclinical evaluations and early-stage clinical studies in drug-resistant patients.
A total of 455 patients enrolled in the SimpliciTB trial. All participants either had drug-susceptible (DS) or drug-resistant (DR) Tb. The trial took place across 26 sites in eight countries: South Africa, Tanzania, Georgia, Brazil, Russia, the Philippines, Uganda, and Malaysia.
Drug-resistant TB develops when the long, complex, decades-old TB drug regimen is administered improperly or when people contract TB from others with a drug-resistant form of the disease. Only around one-third of people with drug-resistant TB infections received treatment in 2021.
The trial allowed the researchers to evaluate the safety and efficacy of BPaMZ in patients with either DS-TB or DR-TB. Results showed that the BPaMZ regimen was highly potent against the TB bacteria. DS-TB patients were found to be 2.93 times more likely to culture convert by week eight.
However, the four-month experimental BPaMZ regimen did not have favourable outcomes concerning noninferiority compared to HRZE in DS-TB. This was due to adherence challenges, with approximately 10% of patients on the BPaMZ course stopping their treatment due to negative side effects.
Treatment for TB needs to evolve
“Recent progress in TB therapeutics has been limited, with few new drug classes emerging in the last 50 years. Innovative clinical trials like SimpliciTB help us better understand how novel drug regimens work against both drug-sensitive and drug-resistant TB, lighting the way to better treatment options for all TB patients,” explained Dr Muge Cevik, a clinical academic in infectious diseases and medical virology based in the Infections and Global Health Research Division of the School of Medicine at St Andrews.
Reports suggest that nearly 500,000 people are infected by a drug-resistant disease yearly. In some regions, as many as 40% of all cases are drug resistant. Novel drug regimens are vital in the fight to bring the TB pandemic under control.
“This study shows the value of St Andrews world-leading partnership working with international collaborators and the TB Alliance. Together, we have a sustained commitment to develop new and better treatments for tuberculosis, which remains a threat to human health globally,” said Professor Stephen Gillespie, leader of the infection group at St Andrews.