Acute myeloid leukemia, or AML, is a complex heterogeneous disease. Due to advanced age at the time of diagnosis and the need for aggressive treatment to achieve remission, AML is often associated with poor survival outcomes. Adults with t-AML and AML-MRC have a particularly poor prognosis.
The development of new treatment options and achieving meaningful improvements in treating these patients has been challenging. The 7+3 chemotherapy regimen has remained the foundation and has been the standard of care for AML induction for over 40 years.
As a pioneer in liposomal nanotechnology research, Dr. Lawrence Mayer has led the development of multiple liposomal products in the pharmaceutical industry. With VYXEOS, he saw an opportunity to answer the high unmet need for adult patients \with newly-diagnosed t-AML or AML-MRC.
VYXEOS is the first FDA-approved dual-drug liposomal technology that encapsulates daunorubicin and cytarabine, the foundation drugs of the 7+3 regimen. VYXEOS was designed for simultaneous delivery of the 2 individual medications in 1 liposome at a fixed 1:5 molar ratio that is sustained in the bone marrow for a prolonged period of time.
How is VYXEOS different from the traditional 7+3 regimen? When administering daunorubicin and cytarabine individually, as with the 7+3 regimen, each drug has its own unique pharmacokinetics and distribution within the body. VYXEOS was developed to control the relative daunorubicin and cytarabine levels that reach leukemia cells.
Designed with dual-drug liposomal technology, VYXEOS is a nanoscale liposome of daunorubicin and cytarabine. Through extensive preclinical research, a molar ratio of one to five of daunorubicin to cytarabine was carefully selected, allowing for a synergistic effect at killing leukemia cells.
Pharmacokinetic studies have demonstrated that following a 90-minute intravenous infusion, VYXEOS exhibits a prolonged half-life with greater than 99% of daunorubicin and cytarabine in the plasma, remaining encapsulated within the liposomes.
Due to the pharmacokinetics and simultaneous delivery, with in vitro and in vivo studies, VYXEOS has been shown to deliver daunorubicin and cytarabine in a fixed one-to-five molar ratio to leukemia cells.
Based on animal models, the mechanism of action for VYXEOS is thought to occur in 3 main steps:
- VYXEOS liposomes enter and persist in the bone marrow.
- The liposomes are taken up by leukemia cells to a greater extent than by normal bone marrow cells in a murine model.
- VYXEOS liposomes undergo degradation, releasing daunorubicin and cytarabine within the intracellular environment.
Once released within the intracellular environment, daunorubicin and cytarabine exert their antineoplastic activity. The 1:5 molar ratio of daunorubicin to cytarabine has been shown to have synergistic effects at killing leukemia cells in vitro and in animal models.
Dr. Arthur Louie is a board-certified clinical oncologist with over 30 years of experience in pharmaceutical research. He led the development of the clinical program for VYXEOS. He will now review some key efficacy and safety data for VYXEOS.
Based on experience throughout the clinical development program, we designed the pivotal phase 3 trial to look at VYXEOS in a population of adults with newly-diagnosed, therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (AML-MRC).
The pivotal phase 3 trial was a multicenter, open-label, active-controlled, superiority trial. In this trial, VYXEOS was studied in a head-to-head comparison versus the standard 7+3 (cytarabine and daunorubicin) regimen. The trial randomized 309 patients with newly-diagnosed t-AML or AML-MRC. This trial included patients with de novo AML with MDS-related cytogenetic abnormalities, AML with a history of myelodysplasia or chronic myelomonocytic leukemia, and t-AML.
The study established that VYXEOS is the first chemotherapy to demonstrate superior overall survival of 9.6 months vs 5.9 months for the control arm in adults with newly-diagnosed t-AML or AML-MRC.
Next, let’s review some safety data from the phase 3 trials. As shown in this table, reported adverse reactions were generally consistent with the known safety profile of daunorubicin and cytarabine therapy. Fatal treatment-emergent CNS hemorrhage not in the setting of progressive disease occurred in 2% of patients in the VYXEOS arm and 0.7% percent of patients in the control arm. VYXEOS was also associated with lower 30- and 60-day mortality rates compared to 7+3.
With its demonstrated improvement in overall survival compared to 7+3 in adult patients with newly-diagnosed therapy-related AML or AML with myelodysplasia-related changes, VYXEOS represents a significant therapeutic advance for these AML patients.
VYXEOS is indicated for the treatment of newly-diagnosed therapy-related acute myeloid leukemia (t‑AML) or AML with myelodysplasia-related changes (AML-MRC) in adults and pediatric patients 1 year and older.
IMPORTANT SAFETY INFORMATION