Breakthroughs Blog: Tuberculosis

At the recent Union World Conference on Lung Health, TB Alliance presented the results of a Phase 2 clinical trial showing that the novel antibiotic candidate sorfequiline has the potential to improve tuberculosis (TB) treatment when combined with pretomanid and linezolid in people with drug-sensitive TB. The regimen was more effective than the current standard of care, and sorfequiline also demonstrated greater activity than bedaquiline, a key component of the BPaL regimen, a previous breakthrough that drastically reduced treatment time for most drug-resistant TB. This new treatment could shorten TB therapy even further. TB Alliance is working with partners ahead of the launch of a Phase 3 trial next year. Researchers at the University of California San Diego and partners have developed a new method to combat antibiotic-resistant bacteria, which could pave the way for developing alternatives to traditional antibiotics for treating a wide range of deadly infections, as the global threat of antimicrobial resistance continues to grow. The researchers used bacteriophages (or phages), which are viruses that infect and kill bacteria. Phages have been used to treat bacterial infections for more than 100 years but are usually limited in the bacterial strains they can successfully target. Researchers overcame this by allowing the pages to evolve alongside bacteria in a controlled laboratory setting for 30 days, enabling the phages to adapt their bacterial defenses, becoming more effective at killing a wide variety of bacterial strains, including drug-resistant ones, and better at suppressing bacterial growth for extended periods. Researchers at Indiana University have developed a molecular test that can simultaneously detect three dangerous fungi much faster than traditional methods, helping patients receive accurate, timely treatment against this growing global challenge. The test works by targeting genetic regions unique to each fungus, and it was much faster and more accurate than standard methods, a key advance as fungal infections are often mistaken for other respiratory illnesses. While the test still needs to be clinically validated in further studies, the research team believe it could eventually fill a major gap in fungal diagnostics. 

The World Health Organization's (WHO's) TB Vaccine Accelerator Council recently published a new report calling for action to ensure equitable access to future tuberculosis (TB) vaccines currently in the pipeline. While the only licensed vaccine for TB is 100 years old and has limited effectiveness in adolescents and adults, as of September, there are 16 candidate vaccines in clinical development, six of which are in Phase 3 trials. WHO estimates that a vaccine for adolescents and adults that is at least 50 percent effective could avert up to 76 million TB cases and 8.5 million deaths over 25 years. However, as the report claims, global demand could far exceed supply in the initial years after a vaccine is approved because there is no designated funding for such a rollout in low- and middle-income countries most affected by TB, which are already facing significant funding shortfalls. In anticipation of these potential bottlenecks and barriers to access, the report identifies six solutions to encourage countries with a high burden of TB, manufacturers, and other funders and stakeholders to start preparing now for the rollout to ensure future vaccines can reach people who need them faster. In a Phase 1 randomized controlled trial, an experimental intranasal vaccine against multiple H5N1 avian flu strains generated a broad immune response, demonstrating the potential of such a vaccine to play a major role in preparing for outbreaks of emerging viruses with evolving strains, as H5N1 continues its worrying spread. The University of Maryland research team tested the vaccine against a placebo in 40 adults between 18 and 45, finding that the vaccine was safe, well-tolerated, and stimulated immunity at various doses. One group received a vaccine dose combined with an adjuvant, an ingredient used to trigger a stronger immune response, and their immune systems were better able to neutralize infected cells for longer, suggesting that the use of an adjuvant could be a promising approach that might allow for lower doses, which could stretch limited vaccine supplies in the event of an outbreak. Last week, IAVI published new findings from the first-in-human Phase 1 clinical trial of its Lassa virus vaccine candidate, which show that one dose of the vaccine triggers robust and long-lasting immunity and is safe. There are no vaccines or treatments currently licensed against the dangerous illness, which causes thousands of deaths in endemic West Africa and has been designated as a priority pathogen with pandemic potential. The trial enrolled 114 volunteers in Liberia and the United States. The candidate, now undergoing a Phase 2a trial in West Africa, is currently the most advanced Lassa fever vaccine candidate in the pipeline and uses the same platform as Merck’s single-dose Ebolavirus vaccine, which is approved in more than a dozen countries. 

A team of chemists from the University of Warwick and Monash University has identified a promising, potent new antibiotic that seems to be much more effective than existing drugs against deadly superbugs like MRSA and shows no signs of resistance so far, encouraging news as the global threat of antimicrobial resistance continues to grow and the pipeline of new antibiotics continues to fall short. The molecule had been overlooked for decades as an intermediate chemical in the natural process to produce another known antibiotic, methylenomycin A, which was discovered 50 years ago, and despite having been synthesized multiple times, the synthetic intermediates have seemingly not been tested before for antimicrobial activity. The new antibiotic is much more potent than methylenomycin A itself—100 times more active against a range of serious bacteria. It could not only be a powerful new tool against rising drug resistance, but this work could also pave the way for new approaches to antibiotic discovery. A team of researchers has developed an antivenom using antibodies from a llama and an alpaca that can neutralize venom from some of the world’s most venomous snakes. Snakebites are a neglected public health issue that kill around 20,000 people in sub-Saharan Africa yearly. Current antivenom treatments are usually specific to a single snake species, and it can be difficult to identify which of the many types of venomous snakes is behind a bite, making timely, effective treatment difficult to achieve. The researchers exposed an alpaca and a llama to venoms from 18 of the most dangerous snake species in sub-Saharan Africa, isolated the antibodies that the animals produced against the venom, and then combined some of those antibodies in a single cocktail. In mice, the treatment protected against toxins from 17 African snake species and reduced skin damage. Many scientists previously thought that developing a broad-spectrum antivenom would require too many antibodies to be practical because some venom can contain up to 100 toxins, but this study shows that a combination of just a handful of antibodies can neutralize the venom of many snake species, paving the way for the development of similar broad-spectrum antivenoms for other areas where snakebites are a common public health challenge. Last week, Cepheid announced that its Xpert MTB/XDR test for tuberculosis (TB) drug resistance has been prequalified by the World Health Organization (WHO), enabling procurement through international agencies and greater access in areas with a high TB burden. The test is designed to detect resistance to multiple first- and second-line TB drugs from patient samples. It also delivers results quickly, within 90 minutes, allowing health care providers to make quicker, more reliable treatment decisions and have a better understanding of drug resistance, especially in regions with a high TB burden where timing and accuracy are critically important. 

An international research team led by the University of Liverpool has discovered an exciting new class of antibiotics with the potential to target some of the world’s most dangerous multidrug-resistant bacteria, including MRSA and Enterococcus faecium, as experts continue to warn of the growing global threat of antimicrobial resistance. The new class, Novltex, targets a key component of bacterial cell walls that does not mutate, meaning that, unlike traditional antibiotics, it could offer long-lasting protection against antibiotic-resistant strains of bacteria. Novltex is a synthetically designed platform, making it cheaper to produce and easier to scale up for global use than common antibiotics that utilize complex, expensive natural molecules. In studies so far, researchers found Novltex to be potent and fast-acting, even at low doses, and safe. A research team led by investigators at Weill Cornell Medicine has been awarded a five-year, $20.8 million grant from the National Institute of Allergy and Infectious Diseases at the US National Institutes of Health to further the preclinical development of a promising experimental HIV vaccine for pediatric populations. Experts agree that a preventive vaccine for HIV could help turn the tide of the pandemic. Previous studies of the experimental vaccine found that it was safe and may be effective in infants, although it seems to only work in young immune systems, not in adults. The new funding will support optimization of the vaccine in preparation for clinical trials in infants in parts of the world with a high burden of HIV. Researchers at Tulane University have designed an optimized CRISPR-based tuberculosis (TB) test that uses a simple tongue swab, which, if it continues to demonstrate promise, could be a breakthrough for TB testing. Current TB tests often rely on sputum, which can be difficult to collect and which not everyone can produce, and require sophisticated laboratory equipment and skilled health care workers, leading to gaps in diagnosis, particularly in low-resource settings. The researchers built on a previous CRISPR-based TB test, developing an assay that they found to be highly effective using tongue swabs and also highly sensitive in detecting TB in respiratory, pediatric stool, and spinal fluid samples. This painless and low-resource method could improve access to TB testing, particularly at the point of care in remote and low-resource communities.