E7107

E7107 is a semisynthetic derivative of pladienolide B, a natural product originally isolated from Streptomyces platensis. It is the first-in-class small molecule inhibitor targeting the spliceosome, specifically binding to Splicing factor 3B subunit 1 (SF3B1). By inhibiting SF3B1, E7107 blocks normal pre-mRNA splicing in oncogenes, leading to antitumor effects. The drug was developed as an anticancer agent and underwent Phase I clinical trials for advanced solid tumors. However, its development was suspended due to unacceptable adverse events, including cases of vision loss and severe gastrointestinal toxicity[1][4][6][7].