CYP3A4 and tuberculosis: Concomitant HIV and TB treatments are challenging because significant drug–drug interactions, overlapping toxicities, and immune reconstitution inflammatory syndrome.[11–13] Efavirenz and rifampicin, the cornerstones of first-line cART and anti- TB treatments, respectively, are potent inducers CYP2B6 and CYP3A enzymes and transporter proteins.[10,14,15] Efavirenz is mainly metabolized by genetically polymorphic CYP2B6 and to some extent by CYP3A enzymes.