## **Core Concept**
The treatment of multidrug-resistant tuberculosis (MDR-TB) involves the use of second-line drugs, as the bacteria are resistant to the first-line drugs, including isoniazid and rifampicin. The management of MDR-TB requires a combination of drugs to which the bacteria are still susceptible. Recently, newer drugs have been introduced to improve treatment outcomes.

## **Why the Correct Answer is Right**
The correct answer, , refers to Bedaquiline. Bedaquiline is a diarylquinoline antimycobacterial drug that works by inhibiting the proton pump for ATP synthase of mycobacteria, thereby disrupting the bacterial cell's energy production. It was approved by the US FDA in 2012 for the treatment of MDR-TB and has been shown to improve treatment outcomes.

## **Why Each Wrong Option is Incorrect**
- **Option A:** - This option is incorrect because although is used in the treatment of TB, it is not specified here.
- **Option B:** - This option is incorrect as is not the latest drug specifically used for MDR-TB.
- **Option C:** - This option is incorrect because is not the correct answer.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that Bedaquiline is used in combination with other drugs for the treatment of MDR-TB and requires careful monitoring due to potential side effects, including QT prolongation. Its use has been a significant advancement in the treatment of MDR-TB.

## **Correct Answer:** . Bedaquiline