A selective BCL-XL PROTAC degrader achieves safe and potent antitumor activity

B-cell lymphoma extra large (BCL-XL) is a well-validated cancer target. However, the on-target and dose-limiting thrombocytopenia limits the use of BCL-XL inhibitors, such as ABT263, as safe and effective anticancer agents. To reduce the toxicity of ABT263, we converted it into DT2216, a BCL-XL proteolysis-targeting chimera (PROTAC), that targets BCL-XL to the Von Hippel-Lindau (VHL) E3 ligase for degradation. We found that DT2216 was more...