…oral ATR inhibitor BAY 1895344 intermittently dosed 5–80 mg twice daily…The first patient had hormone receptor positive, human epidermal growth factor receptor 2-negative, platinum-refractory breast cancer and had ATM expression in ≤2% of tumor cells by IHC in a fresh baseline tumor biopsy and an ATM deleterious mutation (ATM_T2333fs*) with an allele frequency of 71%. This patient…achieved a RECIST partial response (best response of −54% in target lesion size, in addition to −50% and −40% in 2 liver lesions) with a treatment duration of 349 days…