In our cohort of 13 HMCLs and by contrast to previous results, CX5461 was more efficient in TP53wt than in TP53abn HMCLs...ATR inhibitor VE-821 (2.5mM) was efficient in both types of HMCLs (mean of death in TP53wt was 45% and 28% in TP53abn HMCLs, p=0.6). Combination of CX5641 (0.5mM) with VE-821 (2.5mM) was more efficient than each drug alone and efficacy was not dependent on TP53 status (mean of death in TP53wt was 69% versus 56% in TP53abn HMCLs, p=0.6): interestingly, combo was efficient in all TP53abn HMCLs, being either additive (n=5) or even synergistic (n=3)....Preliminary results of combos in 6 consecutive primary samples with MM or plasma cell leukemia (3 TP53wt and 3 TP53abn) demonstrated efficacy.