Rifapentine differs from rifampicin in a property that allows once-weekly dosing in selected latent tuberculosis regimens such as the 3HP schedule. This distinguishing property is:

• A Complete oral bioavailability without food requirement
• B Absence of CYP450 enzyme induction
• C Activity against non-replicating persisters only
• D Much longer plasma half-life permitting intermittent dosing ✓

Explanation

Rifapentine shares the rifamycin mechanism of inhibiting DNA-dependent RNA polymerase but has a half-life roughly five times longer than rifampicin, enabling once-weekly administration with isoniazid for 12 doses over 3 months (3HP) for latent TB. It still induces cytochrome P450 enzymes, so drug interactions persist. Like other rifamycins it acts on replicating bacilli and discolours body fluids orange.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 13th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.