TUBERCULOSIS IS the world’s deadliest infectious disease. In 2017, the World Health Organization reported that about 10 million people globally developed active tuberculosis, which is caused by the bacterium Mycobacterium tuberculosis, and that 1.6 million died from the disease.
While the illness can be cured, not everyone gets treatment — the WHO has identified “large and persistent gaps in detection and treatment” — and those who do sometimes quit taking the big handful of pills prematurely. Another factor is the rise of drug-resistant strains that are more difficult to treat.
Now, there is evidence of an effective new antibiotic that might help save lives among those with the most highly drug-resistant strains. The Food and Drug Administration on Wednesday approved the new compound, Pretomanid, for use with two other drugs. The combination was tested in a trial with 109 patients, the agency said, and a surprising 89 percent were effectively treated. This compares to other treatments that require many more pills and have been effective only about 34 percent of the time; for the most extremely resistant strain, the cure rate is far less. Although the sample in the Pretomanid study was small, and some experts have urged larger clinical trials, the apparent success rate offers hope for progress against one of the world’s most difficult public-health problems. The number of people with highly drug-resistant TB is estimated to be greater than 40,000 worldwide. In the United States, the cases have been relatively few.
Antibiotic resistance occurs as bacteria evolve, and it is a continuing and serious challenge. While antibiotics discovered after World War II became a pillar of modern medicine, the pipeline of new drugs has not kept up. One reason is that drug discovery and development are extremely expensive, but antibiotics generally don’t provide a large return on investment. Pharmaceutical companies have not had a strong incentive to pour research funds into the search for new antibiotics.
One alternative is public-private partnerships that would stimulate research and not rely solely on the market. This new drug was developed by the TB Alliance, a nonprofit group attempting to leverage cooperation from different sectors to come up with new, fast-acting and affordable drugs to fight TB. It is encouraging to see a nonprofit partnership produce a success like this — the world could use many more.
In another innovation, Pretomanid became the second drug to utilize a special regulatory pathway at the FDA. The Limited Population Pathway for Antibacterial and Antifungal Drugs, or LPAD, was established by Congress in the 21st Century Cures Act in 2016 to speed development and approval of antibiotics to treat serious or life-threatening infections in a limited population of patients. It allows for smaller, shorter or fewer clinical trials than the drawn-out and potentially costly process in regular drug development. If Pretomanid saves lives and continues to show such high rates of efficacy, the new regulatory path will have been worth it. Hopefully this is a harbinger of more successful attempts to come up with novel antibiotics.