The US Food and Drug Administration (FDA) approved a new drug for the treatment of a deadly type of treatment-resistant tuberculosis, one of the world’s leading infectious causes of death.
The tablets called Pretomanid is approved in combination with bedaquiline and linezolid for treating a limited and specific population of adult patients with extensively drug resistant, treatment-intolerant or nonresponsive multidrug resistant tuberculosis of the lung. Tuberculosis, or TB, is spread by droplets that are sneezed or coughed by someone infected and typically attacks the lungs and then other parts of the body, if not treated. Like other bacterial infections, TB must be treated with a cocktail of drugs, rather than a single therapy, to prevent the microbes from developing resistance and roaring back.
About 10 million people globally developed TB in 2017, and of them, about 558,000 had a form that was resistant to at least one TB drug, according to the World Health Organization. An estimated 1.6 million died of the disease in 2017. The FDA cleared Pretomanid using a relatively new pathway established under a 2016 federal law to spur the development of new antibiotics and antifungal drugs for infections that lack effective treatment. Unusually, the drug was developed by a not-for-profit. The group, the Global Alliance for TB Drug Development Inc., or TB Alliance, acquired the rights to develop the pill in 2002 from Chiron Corp. The group developed Pretomanid with funding from multiple partners. “We’re very optimistic that this will help save a lot of lives,” said Mel Spigelman, president and CEO of the TB Alliance. “If we can find good new drugs, even the worst cases of TB can be treated in a reasonable manner.”
The regimen’s half-year duration could make treatment easier for patients with extensively drug-resistant or multidrug-resistant TB. They have faced courses of treatment lasting 18 months or more with multiple drugs, many of which are decades old and have toxic side effects. Many of these patients die despite the intense treatment, because the drugs don’t work against their infections. Pretomanid is only the third new TB drug to be approved by the FDA in more than 40 years, according to the TB Alliance. The group’s aim in developing the new pill was to provide more effective treatment by including it in a new regimen, rather than adding it to existing treatments.
“We’ve always had this idea that just adding on one drug, that’s not going to do much,” Dr. Spigelman said. “If we really wanted to make that quantum leap, then we had to replace the whole regimen.”The ultimate goal, he said, is to make the new combination into the regimen of choice for all TB patients. The TB Alliance is studying whether it can reduce doses of or replace linezolid in the regimen because that drug carries significant side effects, namely nerve damage and anemia, he said.