Scientists at Texas Biomedical Research Institute are investigating new approaches to combating tuberculosis, a bacterial infection that has grown resistant to the standard cocktail of antibiotics used to treat the disease.
Although tuberculosis is typically thought of as a disease of the past in the Western World, it’s still the leading cause of death from infectious diseases worldwide.
Local researchers will look at an emerging approach to fighting drug-resistant infections known as host-directed therapy. Instead of attacking the pathogen directly, host-directed therapy boosts the body’s immune system and dampens inflammation — similar to immunotherapy treatments used against certain cancers.
“If we think of the immune system as the light bulb, TB infection dims the light, dampens the immune response so that it can grow,” said Eusondia Arnett, a molecular biologist at Texas Biomed who is co-leading the study. “Host-directed therapy is going to turn the light bulb back on, (activating) the immune system to kill the bug.”
Over 1.2 million people died from tuberculosis in 2024, according to the World Health Organization. The disease is especially rampant and deadly in poorer countries with less medical infrastructure and access to treatment.
The U.S. sees around 10,000 cases of tuberculosis every year, according to the U.S. Centers for Disease Control and Prevention, and a majority of those cases occur in people born outside of the country.
Symptoms of tuberculosis often include a persistent cough, chest pain, shortness of breath, night sweats, coughing up blood, fever, unexplained weight loss and lack of appetite.
A portion of tuberculosis cases are drug resistant, meaning the infection doesn’t respond to some of the main drugs used to treat the disease. There are also rare cases where nearly all medications are ineffective. Worldwide, an estimated 390,000 people developed drug-resistant tuberculosis in 2024, according to the WHO.
“It’s really reduced what’s out there that can be used to help treat TB,” Arnett said.
Many bacterial infections are seeing increasing resistance to conventional drugs, an issue that researchers estimated could lead to nearly 40 million deaths worldwide between 2025 and 2050.
Host-directed therapy is one emerging candidate in the fight against these microbes, but monoclonal antibodies, phages and new vaccines and antibiotics are also in the works.
Texas has the second largest population of tuberculosis patients in the U.S., behind California alone. Bexar County records between 60 and 90 cases of the disease in a typical year, state data shows.
San Antonio is also home to the Texas Center for Infectious Disease, the last freestanding tuberculosis hospital in the U.S., the City Chest Clinic, a tuberculosis screening and treatment provider operated by the San Antonio Metropolitan Health District, and the Heartland National TB Center, a CDC-funded tuberculosis training and consultation center.
And researchers like Arnett work to advance understanding of the disease and new ways of treating it through Texas Biomed’s IN-TRAC research program.
With the help of $200,000 in grant funding from Lyda Hill Philanthropies, Arnett and collaborators will look at methods of getting host-directed therapy into the lungs, where tuberculosis does the most damage.
Dr. Larry Schlesinger, Texas Biomed’s president and CEO, and Arnett are co-leading the project. Researchers with San Antonio’s Southwest Research Institute, Texas A&M University, the University of Texas and Colorado State University will also be a part of the project.
The therapy could help tamp down the systemic inflammation that comes with tuberculosis and the accompanying lung damage it causes, which can linger even after the infection clears, Arnett said.
It might also reduce the time tuberculosis patients spend on long and unpleasant treatment plans for the disease. Treatment plans typically include around a dozen pills taken daily — with side effects such as nausea, fatigue and flu-like symptoms — over the course of several months to over a year.
“I’m just mindful as a clinician of the burdens on our patients,” said Dr. Lisa Armitige, co-medical director of the Heartland National TB Center. “We try to lessen those as much as we can, but really the treatment is the treatment. It’s effective, but it’s not easy.”
The host-directed therapy research will take years and any treatment would still need to go through the approval process by the U.S. Food and Drug Administration.
Arnett said that the team has chosen certain pathways that are already FDA-approved or being tested in clinical trials as potential cancer treatments so that the research could go from the lab to the clinic quicker.
“We’ve been focusing on combinations of compounds that are already FDA-approved for treatment of some leukemias and pairing them with other chemicals that are now in phase one or two clinical trials for cancer,” she said. “We hope that by building on that … we can more readily translate this into the clinic.”
