GSPT1 and acute myeloid leukemia: As the representative GSPT1/BTK heterobifunctional degrader, GBD‐9 efficiently concurrently degraded GSPT1 acting as an MGD and degraded BTK1 acting as a PROTACs by recruiting CRBN, and displayed high activity in various diffuse large B‐cell lymphoma (DLBCL) and AML cell lines.