Cadazolid is an experimental antibiotic of the oxazolidinone class made by Actelion Pharmaceuticals Ltd. which is effective against Clostridium difficile, a major cause of drug resistant diarrhea in the elderly.[1] Current drug treatments for this infection involve orally delivered antibiotics, principally fidaxomicin, metronidazole and vancomycin; the last two drugs are the principal therapeutic agents in use, but fail in approximately 20 to 45% of the cases. The drug works by inhibiting synthesis of proteins in the bacteria, thus inhibiting the production of toxins and the formation of spores.[2] Cadazolid progressed through to Phase III clinical trials,[1] but in its financial results for Q1 2018, Idorsia mentions that Actelion informed them that "following completion of Phase 3 data analysis of cadazolid - it has decided to discontinue the development of the compound."[3] __TOC__
The chemical structure of cadazolid combines the pharmacophores of oxazolidinone and fluoroquinolone antibiotics.[2]
In a study published in the journal Anaerobe, cadazolid has been shown to be effective in vitro against 133 strains of Clostridium difficile all collected from Sweden.[4]
In phase I tests, sixty four male patients reacted favourably to cadazolid which primarily acted and remained in the colon while displaying little toxicity even in regimes involving large doses.[1]