* Sirturo uses new mechanism to fight TB
* Blocks enzyme TB bacteria need to survive
* Will carry warning about risks, including death
By Toni Clarke
Dec 31 U.S. health regulators have approved a
new Johnson & Johnson drug for patients with
tuberculosis who do not respond to other treatments, the company
The drug is the first in 40 years to tackle the disease
using a new mechanism of action, according to J&J. The drug
blocks an energy-producing enzyme that tuberculosis bacteria
need to survive.
The U.S. Food and Drug Administration approved the drug,
chemically known as bedaquiline and to be marketed as Sirturo,
on Monday following a positive review by an advisory panel last
Tuberculosis is an air-spread infection that usually attacks
the lungs but it can also affect the brain, the spine and the
In 2011, nearly 9 million people around the world became
sick with TB, according to the Centers for Disease Control and
Prevention, and there were 1.4 million TB-related deaths. The
disease requires six to nine months of drug treatment.
TB is more prevalent now than at any time in history, FDA
Commissioner Margaret Hamburg wrote in a blog on the FDA
website. This drug will help treat and cure patients who are
putting themselves and others at serious health risk, she said.
The drug itself has significant potential risks, she wrote,
and will carry a warning about an increased rate of death
observed in patients who received it.
Her comments followed those of the FDA advisers who found
the drug to be effective, though they noted that more deaths
were seen in the group of patients who took bedaquiline in
combination with standard treatments than in the group that took
standard drugs alone.
Doctors Without Borders said that the drug was a "potential
game changer" against drug-resistant forms of the disease and an
important milestone in fighting TB.
Multidrug-resistant tuberculosis is caused by strains of the
bacterium that have become resistant to at least isoniazid and
rifampin, the two most potent drugs for TB.
Support has not been unanimous. Consumer advocacy group
Public Citizen earlier this month said it had written to the FDA
because of the risks of death asking it not to approve of the
drug, which received a fast approval.
DETAILS FROM TRIAL
Chrispin Kambili, medical affairs leader for bedaquiline at
J&J's Janssen Therapeutics unit, said in a recent interview that
the company is studying the difference in death rates but has so
far seen no common pattern.
Almost every death was due to a different cause, including a
motor vehicle accident. What was unusual, he said, was the low
rate of death in the placebo group.
Advisers to the FDA expressed concern that a greater number
of patients had elevated liver enzymes, a potential sign of
liver toxicity, and elongated QT levels, an electrical
irregularity in the heart that can cause sudden death.
But Kambili said none of the patients died due to serious QT
prolongation and there was no unifying findings in the data.
Kambili said J&J's drug is designed for a relatively small
portion of patients - some 650,000 - who do not respond to
And while investment analysts at Cowen and Co have forecast
peak annual sales of the product at a relatively modest $300
million, the drug is important from a public health standpoint,
J&J shares were 0.1 percent higher to $69.56 in late morning
trading on the New York Stock Exchange.