The U.S. Food and Drug Administration announced on Monday that it has approved Sirturo (bedaquiline) to treat multiple drug resistant tuberculosis (MDR-TB) in adults when all other treatments fail.

The drug is manufactured by Johnson & Johnson and it's the first drug with a new mechanism of action to be approved for tuberculosis in over 40 years.

TB, one of the world's deadliest diseases is caused by Mycobacterium tuberculosis. The disease spreads from person to person and infects mainly lungs. However, other organs like kidney and brain can also be affected.

In 1993, WHO declared TB as a global public health emergency. According to a report by the agency, in 2010 there were 8.8 million people in the world who were diagnosed with TB. In the same year, as many as 650,000 people were diagnosed with MDR-TB.

Multi-drug resistant TB occurs when the bacteria becomes resistant to isonazid and rifampin, two powerful drugs most commonly used to treat TB. The new drug, Sirturo, works by inhibiting enzyme needed by M. tuberculosis to spread throughout the body. It must be used in combination with other drugs that are used to treat TB, according to FDA.

"Multi-drug resistant tuberculosis poses a serious health threat throughout the world, and Sirturo provides much-needed treatment for patients who have don't have other therapeutic options available. However, because the drug also carries some significant risks, doctors should make sure they use it appropriately and only in patients who don't have other treatment options," said Edward Cox, director of the Office of Antimicrobial Products in the FDA's Center for Drug Evaluation and Research, in a statement.

Side-effects of the drug include nausea, joint pain, and headache, according to FDA. The drug also carries a boxed warning as the use of drug can cause abnormal heart rhythm.