AIFM2 and neoplasm: However, because the first described FSP1-specific inhibitor iFSP1 (ref. 5) does not qualify to be further developed as an anti-cancer drug, owing to its limited potential for medicinal chemistry development in terms of an unfavourable structure and substitution pattern16, next-generation, efficacious in vivo FSP1 inhibitors for tumour treatment are urgently required.