Ehab Atallah, MD
This month, two studies reported on the addition of novel therapies to the backbone of low dose cytarabine. The first study, evaluated the role of adding quizartinib to low-dose cytarabine (LDAC) in older patients with acute myeloid leukemia (AML) not suitable for intensive chemotherapy. The addition of quizartinib to LDAC vs. LDAC alone improved survival and response in older patients with AML with an FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation who were unfit for intensive chemotherapy (IC). Among patients with FLT3-ITD mutation, LDAC+quizartinib improved response in 38% of patients vs. 0% of patients receiving LDAC alone (P = .02). The 2-year overall survival also improved significantly in patients receiving LDAC+quizartinib (hazard ratio [HR] 0.36; P = .024). The study included 202 older patients with AML (de novo AML 63%; secondary AML 25%; high-risk myelodysplastic syndrome 11%) unsuitable for IC with (n = 27) or without FLT3-ITD mutation randomly assigned to receive LDAC+quizartinib or LDAC alone.1
The second study evaluated the combination of LDAC with venetoclax vs. placebo in treatment-naive patients with AML ineligible for IC. LDAC+venetoclax vs. LDAC+placebo improved median overall survival (HR 0.70; P = .04), along with higher rates of complete response (CR) or CR with incomplete hematologic recovery (CRi) (48.3% vs. 13.2%; P < .001) and postbaseline red blood cell and platelet transfusion independence (39.2% vs. 17.6%; P = .002). This was a post hoc analysis performed after an additional 6 months of follow-up of the phase 3 VIALE-C trial, including 211 adult patients with AML who were treatment-naive and unsuitable for IC. Patients were randomly assigned to receive LDAC with venetoclax (n = 143) or placebo (n = 68).2 This study was previously reported with a shorter follow up and ddi not demonstrate a survival difference for LDAC+venetoclax vs. LDAC alone. It is very reassuring to see these results with longer follow-up with an improvement of the median overall survival from 4.1 months with LDAC alone to 8.4 months with LDAC+venetoclax. In addition, responses were seen in patients who had prior hypomethylating agents. The CR, CR/CRi and CR/CR with partial hematologic recovery (CRh) rates were 7%, 29%, and 21% respectively.
Finally in a study by Roboz et al. patients who received oral azacytidine as maintenance had no worsening of fatigue or health-related quality of life. Maintenance therapy with oral azacitidine (oral-AZA) did not negatively affect fatigue and health-related quality of life (HrQoL) in patients with acute myeloid leukemia (AML) in complete remission (CR) or CR with incomplete hematologic recovery (CRi) after intensive chemotherapy (IC). Effects of oral-AZA on fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue: difference in overall least square mean change [D] −0.89; 95% CI −2.37- 0.59) and HrQoL (EQ-5D-3L health utility index: D −0.01; 95% CI, −0.03-0.01; EQ-5D visual analog: D −0.95; 95% CI, −4.38-2.47) were comparable to placebo. Findings are from the QUAZAR AML-001 trial, including 444 patients with AML with intermediate- or poor-risk cytogenetics at diagnosis and unsuitable for transplantation. The patients were randomly assigned to receive either oral-AZA (n = 225) or placebo (n = 219) in first CR/CRi after IC. One caveat is that the assessments were performed on Day 1 of each 28 day cycle, which may have allowed for the recovery from side effects of oral azacytidine.3
References
- Dennis M et al. Randomised evaluation of quizartinib and low-dose ara-C vs low-dose ara-C in older acute myeloid leukemia patients. Blood Adv. 2021 Oct 1.
- Wei AH et al. 6-month follow-up of VIALE-C demonstrates improved and durable efficacy in patients with untreated AML ineligible for intensive chemotherapy. Blood Cancer J. 2021;11:163.
- Roboz GJ et al. Oral azacitidine preserves favorable level of fatigue and health-related quality of life for patients with acute myeloid leukemia in remission: results from the phase 3, placebo-controlled QUAZAR AML-001 trial. Haematologica. 2021 Sep 23.