Today, The Lancet launched an impressive new series of articles on the global tuberculosis epidemic, which claims 1.8 million lives every year. The Lancet articles note that TB is a leading cause of death in people in the most economically productive age-groups. The series highlights scale up of treatment and diagnoses, drug-resistant TB, and HIV/TB co-infection, as well as the huge funding gap for TB control and research and development, with many countries struggling to deliver basic diagnostic and treatment services.
The authors of one lead article conclude: “Acceleration of the present decline towards TB elimination will need invigorated actions in four broad areas: continued scale-up of early diagnosis and proper treatment in line with the Stop TB Strategy; development and enforcement of bold health-system policies; establishment of links with the broader development agenda; and promotion and intensification of research.”
With the unveiling of this series, we spoke today with Zhenkun Ma, Ph.D., Chief Scientific Officer for the TB Alliance, who authored this article focused on TB drug development and the promise of new medicines to greatly improve TB treatment.
Q: You point to the results of a modeling study that suggests the combination of a 2-month treatment regimen that cures 95% of MDR tuberculosis, a better TB diagnostic tool, and a joint pre-exposure and post-exposure TB vaccine could potentially reduce the incidence of this disease by 71% by 2050. But that seems like a very tall order. How realistic is it that we can achieve those goals and what will it take to get there?
A: I think it’s very feasible. We have a very strong pipeline. On the drugs front, the goal of achieving a 95 percent cure rate for drug-resistant TB with new drugs is very doable. Right now, there are 10 drugs in clinical development, and the majority—six new drugs—belong to novel drug classes with new modes of action, new mechanisms. Bacterium has never seen these compounds before. They work differently from old drugs and are able to overcome drug-resistant forms of TB.
Four of the drugs in the pipeline are currently being used to treat other bacterial infections. We are in the process of figuring out how to best use these to treat TB. Because of these developments, I think it’s very feasible to achieve significant reductions in TB incidence.
Q: One problem you highlight is inadequate clinical trial capacity to test new regimens for TB treatment. Can you elaborate on that? Why isn’t there enough capacity, how inadequate is it, and what will it take to get to full capacity?
A: TB has its worst impact on developing countries. The places you have TB patients, generally, do not have the capacity to conduct modern clinical trials. Most parts of Africa, for example, simply don’t have the laboratory capacity required to support registration trials. And the places we are able to conduct registration trials, you simply don’t have enough patients with TB. So that’s the challenge and the disconnect. Funding is really the key to support capacity building and clinical capacity strengthening.
Q: What research is currently underway to improve pediatric treatment of TB?
A: Pediatric TB has largely been ignored. It’s a major challenge because it’s hard to do. We don’t have very good diagnostic tools. It will take a lot of research work to figure out how best to detect TB and monitor the efficacy of treatments in children. However, we are committed to developing drugs that can be used for all patient populations.
Q: The funding shortfall for TB research is huge. It has long been a neglected disease. What do you think it will take to change that?
A: Clearly the funding gap is huge. MSF recently reported there is a 75 percent gap in the funds needed for TB research and development. A lot of people think TB is simply not a problem anymore. The Lancet articles are a great opportunity to point out that TB is still a devastating global problem, with 2 million people dying from TB and more than 9 million new cases of TB occurring each year. This is really a massive global problem and requires people to pay more attention and invest more resources. We need all the stakeholders to allocate more resources to support TB drug development.