The invention relates to a pharmaceutical composition comprising a compound preventing EthR from binding to the ethA promoter, for example a compound of formula 1 wherein R1 is optionally substituted phenyl or optionally substituted pyridyl; R2 (CH2)n wherein n is 1, 2, 3 or 4; R3 is CH3(CH2)m wherein m is 0, 1, 2 or 3; X1 is O, S, NH, N(CH3) or CH2; and X2 is O, S or NH; in particular 2-phenylethyl butyrate, and a thioamide or thiourea of formula 2 wherein R4 is optionally substituted phenyl, optionally substituted pyridyl, optionally substituted indolyl, —NR7R8; or —NH—N═CH—R9; and substituents R5 to R9 have the meanings indicated in the description, in particular ethionamide. The pharmaceutical composition is useful, e.g., in the treatment of multidrug-resistant tuberculosis.