A patient with multidrug-resistant tuberculosis (MDR-TB) is started on bedaquiline. The unique mechanism of action of bedaquiline that differentiates it from all other anti-TB drugs is:

• A Inhibition of mycobacterial DNA gyrase
• B Disruption of mycolic acid synthesis in the cell wall
• C Inhibition of mycobacterial 50S ribosomal subunit
• D Inhibition of mycobacterial ATP synthase (F0F1 subunit) ✓

Explanation

Bedaquiline specifically inhibits the mycobacterial ATP synthase (the F0 proton pump subunit), blocking ATP production and depleting energy stores in mycobacteria. This mechanism is entirely novel among antitubercular drugs and is active against both replicating and non-replicating (dormant) bacilli. Because it is mycobacterium-specific, it does not affect human mitochondrial ATP synthase at therapeutic concentrations, though QTc prolongation is a significant adverse effect requiring monitoring.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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