Data from Outcomes in Patients with Poor-Risk Cytogenetics with or without <i>TP53</i> Mutations Treated with Venetoclax and Azacitidine

AbstractPurpose:

To evaluate efficacy and safety of venetoclax + azacitidine in treatment-naïve patients with acute myeloid leukemia harboring poor-risk cytogenetics and TP53^mut or TP53^wt.

Patients and Methods:

We analyzed data from a phase III study (NCT02993523) comparing venetoclax (400 mg orally days 1–28) + azacitidine (75 mg/m² days 1–7) or placebo + azacitidine, and from a phase Ib study (NCT02203773) of venetoclax + azacitidine. Patients were ineligible for intensive therapy. TP53 status was analyzed centrally; cytogenetic studies were performed locally.

Results:

Patients (n = 127) with poor-risk cytogenetics receiving venetoclax + azacitidine (TP53^wt = 50; TP53^mut = 54) were compared with patients with poor-risk cytogenetics (n = 56) receiving azacitidine alone (TP53^wt = 22; TP53^mut = 18).

For poor-risk cytogenetics + TP53^wt patients, venetoclax + azacitidine versus azacitidine alone resulted in composite remission rates (CRc) of 70% versus 23%, median duration of remission (DoR) of 18.4 versus 8.5 months, and median overall survival (OS) of 23.4 versus 11.3 months, respectively. Outcomes with venetoclax + azacitidine were comparable with similarly treated patients with intermediate-risk cytogenetics and TP53^wt.

For poor-risk cytogenetics + TP53^mut patients, venetoclax + azacitidine versus azacitidine alone resulted in CRc of 41% versus 17%, median DoR of 6.5 versus 6.7 months, and median OS of 5.2 versus 4.9 months, respectively.

For poor-risk cytogenetics + TP53^mut patients, predominant grade ≥3 adverse events (AE) for venetoclax + azacitidine versus azacitidine were febrile neutropenia (55%/39%), thrombocytopenia (28%/28%), neutropenia (26%/17%), anemia (13%/6%), and pneumonia (28%/33%). AEs were comparable between TP53^mut and TP53^wt patients.

Conclusions:

In poor-risk cytogenetics + TP53^mut patients, venetoclax + azacitidine improved remission rates but not DoR or OS compared with azacitidine alone. However, in poor-risk cytogenetics + TP53^wt patients, venetoclax + azacitidine resulted in higher remission rates and longer DoR and OS than azacitidine alone, with outcomes comparable with similarly treated patients with intermediate-risk cytogenetics. Toxicities were similar in TP53^mut and TP53^wt patients.

See related commentary by Green and Zeidner, p. 5235