US Approves Drug-Resistant Tuberculosis Treatment

The U.S. Food and Drug Administration has approved a new medication for treating multi-drug resistant tuberculosis (MDR-TB).

Sirturo, known chemically as bedaquiline, is the first new anti-TB therapy approved in more than 40 years. It is also the first designed as part of a combination therapy to treat adults infected with drug-resistant pulmonary TB, when other treatments are unavailable. The new drug works by blocking an enzyme the disease pathogen needs to spread throughout the body.

Developed by Janssen Therapeutics, a division of U.S. drugmaker Johnson & Johnson, Sirturo was approved under the FDA’s accelerated review program that allows promising drugs to be brought to market more quickly.

The federal agency cautions that the medication carries risks of potentially deadly heart problems, and advises doctors to prescribe and administer Sirturo carefully. A consumer health group, Public Citizen, criticized the FDA’s accelerated review of bedaquiline, saying its apparent toxicity “means an increased level of scrutiny should be required for its approval.”

But Dr. Mel Spigelman, president and CEO of the non-profit Global Alliance for TB Drug Development, calls the FDA's approval of Sirturo "the beginning of a new era" in TB treatment. He predicts more powerful therapies will soon emerge to replace the few drugs that have been used to treat TB for the past half-century.

Tuberculosis is one of the world's leading killers. An estimated two-billion people carry the bacterial respiratory infection; more than nine-million people, many living in poverty, have an active form of the disease, which can be spread easily from person to person through the air, by coughing, and by poor sanitary conditions.

Of the nine-million active cases of TB, about half a million are caused by multi-drug resistant tuberculosis, which manifests when the disease pathogen Mycobacterium tuberculosis becomes resistant to isonazid and rifampin, the two drugs most widely used to treat TB.

There were fewer than 100 cases of MDR-TB in the United States last year, but this hard-to-treat and deadlier form of TB poses a growing public health threat throughout much of the developing world, especially in regions of Africa, China, South Asia and Eastern Europe.

The new drug is approved for use only in the United States.