MYLOTARG® (Gemtuzumab ozogamicin)

The FDA on September 1, 2017 approved MYLOTARG® for the treatment of newly-diagnosed CD33-positive Acute Myeloid Leukemia (AML) in adults and for treatment of relapsed or refractory CD33-positive AML in adults and in pediatric patients 2 years and older. MYLOTARG® may be used in combination with Daunorubicin and Cytarabine for adults with newly diagnosed AML, or as a stand-alone treatment for certain adult and pediatric patients. MYLOTARG® is a product of Pfizer Inc.

FDA Approves IDHIFA® for Patients with Relapsed or Refractory Acute Myeloid Leukemia

SUMMARY: The FDA on August 1, 2017 granted regular approval to IDHIFA® (Enasidenib), for the treatment of adult patients with relapsed or refractory Acute Myeloid Leukemia (AML) with an Isocitrate DeHydrogenase-2 (IDH2) mutation, as detected by an FDA-approved test. The American Cancer Society estimates that in 2017, 21,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 10,590 patients will die of the disease. AML can be considered as a group of heterogeneous diseases with different clinical behavior and outcomes. Cytogenetic analysis has been part of routine evaluation when caring for patients with AML. By predicting resistance to therapy, tumor cytogenetics will stratify patients, based on risk and help manage them accordingly. Even though cytotoxic chemotherapy may lead to long term remission and cure in a minority of patients with favorable cytogenetics, patients with high risk features such as unfavorable cytogenetics, molecular abnormalities, prior myelodysplasia and advanced age, have poor outcomes with conventional chemotherapy alone.

Isocitrate DeHydrogenase (IDH) is a metabolic enzyme that helps generate energy from glucose and other metabolites by catalyzing the conversion of Isocitrate to Alpha-Ketoglutarate. Alpha-ketoglutarate is required to properly regulate DNA and histone methylation, which in turn is important for gene expression and cellular differentiation. IDH mutations lead to aberrant DNA methylation and altered gene expression thereby preventing cellular differentiation, with resulting immature undifferentiated cells. IDH mutations may thus promote leukemogenesis in Acute Myeloid Leukemia and tumorigenesis in solid tumors. There are three isoforms of IDH. IDH1 is mainly found in the cytoplasm, as well as in peroxisomes, whereas IDH2 and IDH3 are found in the mitochondria, and are a part of the Krebs cycle. Approximately 20% of patients with AML, 70% of patients with Low-grade Glioma and secondary Glioblastoma, 50% of patients with Chondrosarcoma, 20% of patients with Intrahepatic cholangiocarcinoma, 30% of patients with Angioimmunoblastic T-cell lymphoma and 8% of patients with Myelodysplastic syndromes/Myeloproliferative neoplasms, are associated with IDH mutations.

IDHIFA® is an oral, selective, small molecule inhibitor of mutated IDH2 protein. The approval of IDHIFA® was based on an open label, single arm, multicenter, clinical trial that included 199 adults with relapsed or refractory AML, who had an IDH2 mutation as detected by the RealTime IDH2 Assay. Patients received IDHIFA® 100 mg orally daily. The median age was 67 years, the median number of prior therapies was 2 and a third of the patients had unfavorable cytogenetics. Study endpoints included Complete Response (CR) and Complete Response with partial hematologic recovery (CRh) rates, CR/CRh duration, and conversion from transfusion dependence to transfusion independence.

After a median follow up of 6.6 months, 23% of patients experienced CR or CRh lasting a median of 8.2 months, with 19% of patients having a CR lasting a median 8.2 months, and 4% with a CRh lasting a median 9.6 months. The median time to first response was 1.9 months and the median time to best response of CR/CRh was 3.7 months. Of the 157 patients who required transfusions at the initiation of the trial, 34% of the patients no longer required transfusions during at least one 8 week time period on IDHIFA®. Of the 42 patients who did not require transfusions at the start of the study, 76% maintained transfusion independence. The most common toxicities were nausea, vomiting, diarrhea, elevated bilirubin and decreased appetite. Differentiation syndrome occurred in 14% of patients and these patients should be promptly managed, as this could be fatal.

The authors concluded that IDHIFA® is well tolerated and induced lasting Complete Responses in patients who had failed prior AML therapies, with the clinical efficacy related to differentiation of myeloblasts rather than cytotoxicity. This is the first FDA approval for relapsed or refractory AML specifically with an IDH2 mutation. Enasidenib in mutant-IDH2 relapsed or refractory acute myeloid leukemia (R/R AML): Results of a phase I dose-escalation and expansion study. Stein EM, Dinardo CD, Pollyea DA, et al. J Clin Oncol 35, 2017 (suppl; abstr 7004).

IDHIFA® (Enasidenib)

The FDA on August 1, 2017 granted regular approval to IDHIFA®, for the treatment of adult patients with relapsed or refractory Acute Myeloid Leukemia with an Isocitrate DeHydrogenase-2 (IDH2) mutation, as detected by an FDA-approved test. IDHIFA® is a product of Celgene Corp.

FDA Approves RYDAPT® for FLT3-Mutated Acute Myeloid Leukemia

The FDA on April 28, 2017 approved RYDAPT® (Midostaurin), a multikinase inhibitor, for the treatment of adult patients with newly diagnosed Acute Myeloid Leukemia (AML), who are FLT3 mutation-positive (FLT3+), as detected by an FDA-approved test, in combination with standard Cytarabine and Daunorubicin induction and Cytarabine consolidation. Activating mutations in the FLT3 receptor is the most common genetic abnormality in AML and is detected in approximately 30% of the patients. RYDAPT® along with chemotherapy significantly improved Overall Survival and represents a new standard of care for FLT3-mutated AML patients.

RYDAPT® (Midostaurin)

The FDA on April 28, 2017 approved RYDAPT® for the treatment of adult patients with newly diagnosed Acute Myeloid Leukemia (AML) who are FLT3 mutation-positive (FLT3+), as detected by an FDA-approved test, in combination with standard Cytarabine and Daunorubicin induction and Cytarabine consolidation. RYDAPT® is a product of Novartis Pharmaceuticals Corp.

FDA Approves RYDAPT®, A Targeted Multikinase Inhibitor for FLT3-Mutated Acute Myeloid leukemia

SUMMARY: The FDA on April 28, 2017 approved RYDAPT® for the treatment of adult patients with newly diagnosed Acute Myeloid Leukemia (AML) who are FLT3 mutation-positive (FLT3+), as detected by an FDA-approved test, in combination with standard Cytarabine and Daunorubicin induction and Cytarabine consolidation. The American Cancer Society estimates that in 2017, 21,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 10,590 patients will die of the disease. AML can be considered as a group of heterogeneous diseases with different clinical behavior and outcomes. Cytogenetic analysis has been part of routine evaluation when caring for patients with AML. By predicting resistance to therapy, tumor cytogenetics will stratify patients, based on risk and help manage them accordingly. Even though cytotoxic chemotherapy may lead to long term remission and cure in a minority of patients with favorable cytogenetics, patients with high risk features such as unfavorable cytogenetics, molecular abnormalities, prior myelodysplasia and advanced age, have poor outcomes with conventional chemotherapy alone.

The Fms-Like Tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase in the PDGF family of growth factor receptors located on the cell surface (transmembrane) and plays an important role in both normal and malignant hematopoiesis by activating key signaling pathways. Activating mutations in the FLT3 receptor is the most common genetic abnormality in AML and is detected in approximately 30% of the patients. The three FLT3 mutation subtypes include Tyrosine Kinase Domain (TKD), Internal Tandem Duplications (ITD) high and ITD low. The most common FLT3 mutation is the FLT3-ITD accounting for about 75% of patients with a FLT3 mutation. The presence of FLT3-ITD mutations can negate the benefit of any other favorable molecular and cytogenetic features. Patients with FLT3-ITD mutations are predicted to have poor outcomes with shorter remission duration and significantly decreased leukemia free and overall survival. These mutations are detected using Polymerase Chain Reaction (PCR) based molecular diagnostic DNA testing.

VYXEOS® – A Novel First Line Treatment for High Risk Acute Myeloid Leukemia

SUMMARY: The American Cancer Society estimates that in 2016, 19,950 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 10,430 patients will die of the disease. Acute Myeloid Leukemia in general is a disease of the elderly and the average age of a patient with AML is about 66 years. AML can be considered as a group of heterogeneous diseases with different clinical behavior and outcomes. In general, only 40% of patients younger than 60 years of age survive more than 5 years and 5 year survival for those who relapse after achieving a complete remission (CR) is dismal. Treatment with conventional chemotherapy regimens in elderly patients with secondary AML (sAML) have resulted in poor outcomes. Even though rapid development of new agents against genetic and epigenetic targets is underway, modifications and reformulations of conventional chemotherapy have demonstrated improved outcomes in patients with AML.

CPX-351 (VYXEOS®) is a liposomal formulation of a fixed combination of Cytarabine and Daunorubicin in a 5:1 molar ratio, developed using a platform known as “CombiPlex”. In vitro studies have demonstrated that this ratio maximizes synergy with the lowest level of antagonism and results in preferential uptake of the drug into leukemic cells. In a randomized, open label phase II trial involving patients with or without secondary AML (sAML), CPX-351 improved the composite CR (CRc) rate (Complete Remission and CR with incomplete blood count recovery – CRi) when compared to conventional induction chemotherapy with Daunorubicin and Cytarabine. Those patients with a higher rate of CRc (CR + CRi) had a statistically significant 6 month survival benefit. In another study of AML patients in first relapse, CPX-351 improved median Overall Survival (OS) in poor-risk patients when compared to investigator’s choice of salvage regimens.

On the basis of these studies, the authors conducted a randomized, open-label, phase III trial of first-line CPX-351 in patients with high-risk sAML. Enrolled patients (N=309) were stratified based on AML type (therapy-related AML, AML with a history of MDS with and without prior Hypo Methylating Agent therapy, AML with a history of CMML, or de novo AML with MDS karyotype) and age (60-69 yrs or 70-75yrs). Patients were randomized in a 1:1 ratio to receive either CPX-351 (N=153) 100 units/m2, days 1, 3, 5 or the standard 7+3 (Cytarabine 100 mg/m2/day x 7 days, Daunorubicin 60 mg/m2 days 1, 2, 3) induction therapy (N=156). Both treatment groups were well balanced. The primary end point was Overall Survival (OS) and secondary endpoints included Event Free Survival (EFS), independent blinded assessment of CR+CRi, and 60-day mortality.

The final analysis began after a minimum follow up of 13.7 months. Patients in the CPX-351 group had a significant improvement in Overall Survival compared with standard treatment (HR=0.69; P=0.005; median OS, 9.56 versus 5.95 months). Additionally, there was a significant improvement in Event Free Survival for the CPX-351 group compared to standard therapy (HR=0.74; P=0.021), as well as CR+CRi response (47.7% versus 33.3%; P=0.016) and 60-day mortality (13.7% versus 21.2%). The Complete Remission rates alone were 37.3% and 25.6%, in favor of CPX-351 (P=0.04). Grade 3-5 Adverse Events were similar in frequency and severity in both arms (92% versus 91%) and similar numbers of patients underwent transplantation in both treatment groups.

The authors concluded that treatment with CPX-351 (VYXEOS®) significantly improved Overall Survival, Event Free Survival and Response Rates, without an increase in 60-day mortality or Adverse Events, in elderly patients with high risk secondary AML, when compared with standard induction therapy. CPX-351 reduced the risk of death by 31%. Final results of a phase III randomized trial of CPX-351 versus 7+3 in older patients with newly diagnosed high risk (secondary) AML. Lancet JE, Uy GL, Cortes JE, et al. J Clin Oncol 34, 2016 (suppl; abstr 7000).

Prognostic significance of FLT3 internal tandem duplication, nucleophosmin 1, and CEBPA gene mutations for acute myeloid leukemia patients with normal karyotype and younger than 60 years a systematic review and meta-analysis

SUMMARY: The American Cancer Society estimates that in 2014, 18,860 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 10,460 patients will die of the disease. Acute Myeloid Leukemia in general is a disease of the elderly and the average age of a patient with AML is about 66 years. AML can be considered as a group of heterogeneous diseases with different clinical behavior and outcomes. Cytogenetic analysis has been part of routine evaluation when caring for patients with AML. By predicting resistance to therapy, tumor cytogenetics will stratify patients, based on risk and help manage them accordingly. Even though cytotoxic chemotherapy may lead to long term remission and cure in a minority of patients with favorable cytogenetics, patients with high risk features such as unfavorable cytogenetics, molecular abnormalities, prior myelodysplasia and advanced age, have poor outcomes with conventional chemotherapy. The Fms-Like Tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase in the PDGF family of growth factor receptors located on the cell surface (transmembrane) and plays an important role in both normal and malignant hematopoiesis by activating key signaling pathways. Activating mutations in the FLT3 receptor is the most common genetic abnormality in AML and is detected in approximately 30% of the patients. The most common FLT3 mutation is the FLT3-ITD (Internal Tandem Duplication) mutation caused by tandem duplication within the coding region of the gene. The presence of FLT3-ITD mutations can negate the benefit of any other favorable molecular and cytogenetic features. Patients with FLT3-ITD mutations are predicted to have poor outcomes with shorter remission duration and significantly decreased leukemia free and overall survival. These mutations are detected using Polymerase Chain Reaction (PCR) based molecular diagnostic DNA testing. The authors in this meta-analysis examined the prognostic significance of three mutations frequently noted in patients with cytogenetically normal Acute Myeloid Leukemia. These mutations included FLT3-ITD, mutated NPM1 (Nucleophosmin) and mutations of the CCAAT enhancer-binding protein alpha (CEBPA) gene. This systematic review and meta-analysis included 1942 patients from multiple electronic databases from 2000 to March 2012. It was noted that FLT3-ITD was associated with the worse prognosis, with inferior Overall Survival (OS) and Relapse Free Survival (RFS), whereas mutations in NPM1 and CEBPA genes were associated with a favorable prognosis. The discovery of new molecular mutations in AML patients with normal cytogenetics may help predict outcomes and provide valuable information to facilitate risk-adapted therapy. Port M, Böttcher M, Thol F, et al. Ann Hematol. 2014;93:1279-1286

Final results of a randomized phase 2 study showing the clinical benefit of quizartinib (AC220) in patients with FLT3-ITD positive relapsed or refractory acute myeloid leukemia

SUMMARY: Acute Myeloid Leukemia (AML) is generally a disease of the elderly and the average age of a patient at the time of diagnosis is about 66 years. According to the American Cancer Society, approximately 18,860 new cases of AML will be diagnosed in 2014 and 10,460 patients will die of the disease. AML can be considered as a group of heterogeneous diseases with different clinical behavior and outcomes. Even though cytotoxic chemotherapy may lead to long term remission and cure in a minority of patients with favorable cytogenetics, patients with high risk features such as unfavorable cytogenetics, molecular abnormalities, prior myelodysplasia and advanced age, have poor outcomes with conventional chemotherapy. The fms-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase in the PDGF family of growth factor receptors located on the cell surface (transmembrane) and plays an important role in both normal and malignant hematopoiesis by activating key signaling pathways. Activating mutations in the FLT3 receptor is the most common genetic abnormality in AML and is detected in approximately 30% of the patients. The most common FLT3 mutation is the FLT3-ITD (Internal Tandem Duplication) mutation caused by a tandem duplication within the coding region of the gene. The presence of FLT3-ITD mutations can negate the benefit of any other favorable molecular and cytogenetic features. Patients with FLT3-ITD mutations have poor outcomes with shorter remission duration and significantly decreased leukemia free and overall survival. These mutations are detected using Polymerase Chain Reaction (PCR) based molecular diagnostic DNA testing. Several therapeutic agents are being developed to target FLT3 mutations. Quizartinib (AC220) is an oral tyrosine kinase inhibitor, which has demonstrated activity in patients with both wild type FLT3 as well as those with FLT3-ITD mutations. In this randomized, open label phase II study, the authors evaluated the efficacy and safety of two different, lower dosages of Quizartinib, in patients 18 years of age or older, with FLT3-ITD positive, relapsed or refractory AML. Seventy six patients (N=76) were randomized to receive either Quizartinib 30 mg/day (Group A) or Quizartinib 60 mg/day (Group B), given orally and continuously, during a 28 day treatment cycle. Treatment was continued until relapse, intolerance or Hematopoietic Stem Cell Transplantation (HSCT). Both groups were well balanced except for age over 60 years (42% Group A, 26% Group B) and the percentage with secondary AML (8% Group A, 18% Group B). The composite Complete Remission (CRc) rate included Complete Remission (CR), Complete Remission with incomplete platelet recovery (CRp), and Complete Remission with incomplete hematologic recovery (CRi). The CRc rate in both groups A and B was 47% and the Overall Response Rate (CRc + Partial Response (PR)) was 61% in Group A and 71% in Group B. Further, 32% of patiens in Group A and 42% in Group B were able to undergo HSCT, after achieving CRc or PR. The most common treatment related adverse events were diarrhea (18%), febrile neutropenia (16%), and QT prolongation (15%). The QT prolongation rate was significantly less with lower doses of Quizartinib, as was used in this study, compared to what was noted with higher doses of Quizartinib utilized in other trials. The authors concluded that Quizartinib is highly effective in relapsed and refractory AML patients with FLT3-ITD mutations, with an acceptable safety profile. Schiller GJ, Tallman MS, Goldberg SL, et al. J Clin Oncol 32:5s, 2014 (suppl; abstr 7100)