BACKGROUND: CPX-351 (United States: Vyxeos®; Europe: Vyxeos® Liposomal), a 
dual-drug liposomal encapsulation of daunorubicin and cytarabine in a 
synergistic 1:5 molar ratio, is approved by the US FDA and the EMA for the 
treatment of adults with newly diagnosed therapy-related acute myeloid leukemia 
or acute myeloid leukemia with myelodysplasia-related changes. In a pivotal 
phase 3 study that evaluated 309 patients aged 60 to 75 years with newly 
diagnosed high-risk/secondary acute myeloid leukemia, CPX-351 significantly 
improved median overall survival versus conventional 7 + 3 chemotherapy 
(cytarabine continuous infusion for 7 days plus daunorubicin for 3 days), with a 
comparable safety profile. A Quality-adjusted Time Without Symptoms of disease 
or Toxicity (Q-TWiST) analysis of the phase 3 study was performed to compare 
survival quality between patients receiving CPX-351 versus conventional 7 + 3 
after 5 years of follow-up.
METHODS: Patients were randomized 1:1 between December 20, 2012 and November 11, 
2014 to receive induction with CPX-351 or 7 + 3. Survival time for each patient 
was partitioned into 3 health states: TOX (time with any grade 3 or 4 toxicity 
or prior to remission), TWiST (time in remission without relapse or grade 3 or 4 
toxicity), and REL (time after relapse). Within each treatment arm, Q-TWiST was 
calculated by adding the mean time spent in each health state weighted by its 
respective quality-of-life, represented by health utility. The relative Q-TWiST 
gain, calculated as the difference in Q-TWiST between treatment arms divided by 
the mean survival of the 7 + 3 control arm, was determined in order to evaluate 
results in the context of other Q-TWiST analyses.
RESULTS: The relative Q-TWiST gain with CPX-351 versus 7 + 3 was 53.6% in the 
base case scenario and 39.8% among responding patients. Across various 
sensitivity analyses, the relative Q-TWiST gains for CPX-351 ranged from 48.0 to 
57.6%, remaining well above the standard clinically important difference 
threshold of 15% for oncology.
CONCLUSIONS: This post hoc analysis demonstrates that CPX-351 improved 
quality-adjusted survival, further supporting the clinical benefit in patients 
with newly diagnosed high-risk/secondary acute myeloid leukemia. Trial 
registration This trial was registered on September 28, 2012 at 
www.clinicaltrials.gov as NCT01696084 ( 
https://clinicaltrials.gov/ct2/show/NCT01696084 ) and is complete.