Timcodar (also known as VX-853) is a benzenepropanamide derivative patented by Vertex Pharmaceuticals Incorporated as an efflux pump inhibitor for the treatment of multi-drug resistant bacterial infection. Timcodar potentiates the activity of ethidium bromide (EtBr), a model efflux substrate, against three clinically significant gram-positive pathogens: Staphylococcus aureus, Enterococcus faecalis, and Streptococcus pneumoniae. Timcodar weakly inhibits M. tuberculosis growth in broth culture but shows a 10-fold increase in the growth inhibition of M. Tuberculosis cultured in host macrophage cells and demonstrated synergy with rifampin, moxifloxacin, and bedaquiline. In a mouse model of tuberculosis lung infection, timcodar reduces the likelihood of a relapse infection and potentiates the efficacies of rifampin and isoniazid. Timcodar in combination with Doxorubicin was studied in phase 1/2 clinical trials in patients with solid tumors, but no results have been published.