Which of the following is a latest drug approved for MDR TB?
**Core Concept**
Treatment of multi-drug resistant tuberculosis (MDR-TB) requires the use of multiple drugs to which the bacteria are susceptible. The World Health Organization (WHO) has recommended a regimen that includes a combination of at least four drugs. New drugs are being developed to address the increasing resistance to existing TB medications.
**Why the Correct Answer is Right**
Delamanid (D) is a diarylquinoline antibiotic that was approved by the US FDA in 2014 for the treatment of MDR-TB. It works by inhibiting the mycobacterial ATP synthase enzyme, which is essential for the energy production of Mycobacterium tuberculosis. This leads to the death of the bacteria. Delamanid has shown promise in clinical trials, particularly in combination with other anti-TB medications.
**Why Each Wrong Option is Incorrect**
**Option A:** Bedaquiline (Sirturo) is another new anti-TB medication but it was approved earlier than Delamanid.
**Option B:** Linezolid is an antibiotic used to treat various bacterial infections, but it is not specifically approved for MDR-TB.
**Option C:** Isoniazid is a first-line medication for TB, but it is not a new drug and is not approved for MDR-TB.
**Clinical Pearl / High-Yield Fact**
Delamanid and bedaquiline are the first new anti-TB medications approved since 1966, highlighting the urgent need for new treatments to address the growing crisis of MDR-TB.
**Correct Answer: D. Delamanid.**