Tag: Acute Myeloid Leukemia

Late Breaking Abstract- ASH 2023: ERG is a New Predisposition Gene for Bone Marrow Failure and Hematological Malignancy

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SUMMARY: ERG (ETS-Related Gene) is a known oncogene located on chromosome 21, and is a member of the ETS (erythroblast transformation-specific) family of transcription factors. The ERG gene encodes for a protein also called ERG that functions as a transcriptional regulator, and regulates differentiation of early hematopoietic cells.

ERG has been linked to Down syndrome- associated Acute Megakaryocytic Leukemia. ERG typically via gene-fusions can lead to dysregulated ERG overexpression in hematologic malignancies and solid tumors. ERG can fuse with TMPRSS2 protein to form an oncogenic fusion gene that is commonly found in Hormone-Refractory Prostate Cancer, suggesting that ERG overexpression may contribute to development of androgen-independence in prostate cancer through disruption of androgen receptor signaling. EWS1-ERG fusion has been noted in 10% of Ewing’s Sarcoma cases. ERG is also involved in oncogenesis by generating fusion genes with FUS/TLS in Acute Myeloid Leukemia.

The researchers in this study identified a germline ERG variant associated with bone marrow failure and hematological malignancies. The study originated from a family case involving thrombocytopenia and neutropenia, where the mother developed Acute Myeloid Leukemia (AML) and MyeloDysplastic Syndrome (MDS). ERG, a known oncogene, was discovered as a predisposition gene for bone marrow failure and hematological malignancy. A germline ERG ETS domain variant (p.Y373C) was identified, segregating with thrombocytopenia in a family, leading to AML and therapy-related MDS. Copy neutral Loss of Heterozygosity of chromosome 21q, including the ERG locus, was observed in affected individuals. Validation of their findings involved functional assays, demonstrating Loss of Function variants in ERG, affecting DNA binding and nuclear localization. Experiments using a fetal liver assay confirmed the role of ERG in cytokine-independent growth and leukemia development.

Through global collaborations, 15 heterozygous variants in the ERG gene were identified, including 13 missense and 2 truncating variants in 17 individuals with cytopenia, hematological malignancy or lymphedema. Of these 15 variants, 12 have been confirmed germline. Onset of hematological symptoms ranged from birth to 38 years for truncating and constrained ETS domain variants. Functional studies revealed that most ETS domain missense variants displayed Loss-of-Function (LOF) characteristics affecting transcriptional transactivation, DNA binding, and/or nuclear localization.

This ERG syndrome parallels GATA2 deficiency syndrome (hematological malignancy with lymphedema) and RUNX1 Familial Platelet disorder-myeloid malignancy (thrombocytopenia and hematological malignancy). ERG, like the well-known disease genes GATA2, and RUNX1 is a member of the transcription factor heptad involved in hematopoietic stem cell maintenance and differentiation.

The researchers concluded that germline ERG variants predispose to diverse cytopenia, bone marrow failure and hematological malignancies in both children and adults and ERG adds to a growing list of genes whose unregulated expression contributes to hematological malignancy and other cancers. Identification of germline ERG variants has direct clinical implications for patient and family management including diagnosis, counseling, surveillance, and treatment strategies, such as bone marrow transplant and targeted therapies. Potential clinical implications include ERG screening in germline panels for bone marrow failures and hematological malignancies. Additionally there is a need for further longitudinal studies to understand the natural history of ERG-related syndromes.

ERG is a New Predisposition Gene for Bone Marrow Failure and Hematological Malignancy. Scott HS, Zerella J, Homan C, et al. ASH Annual Meeting & Exposition 2023. LBA-6.

VANFLYTA® (Quizartinib)

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The FDA on July 20, 2023, approved VANFLYTA® (Quizartinib) with standard Cytarabine and Anthracycline induction and Cytarabine consolidation, and as maintenance monotherapy following consolidation chemotherapy, for the treatment of adult patients with newly diagnosed Acute Myeloid Leukemia (AML) that is FLT3 Internal Tandem Duplication (ITD)-positive, as detected by an FDA-approved test. VANFLYTA® is a product of Daiichi Sankyo, Inc.

Long Term Overall Survival Benefit with VIDAZA® plus VENCLEXTA® in Elderly AML Patients

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SUMMARY: The American Cancer Society estimates that in 2023, 20,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,310 patients will die of the disease. AML is one of the most common types of leukemia in adults and can be considered as a group of molecularly heterogeneous diseases with different clinical behavior and outcomes. A significant percentage of patients with newly diagnosed AML are not candidates for intensive chemotherapy or have disease that is refractory to standard chemotherapy. Even with the best available therapies, the 5-year Overall Survival in patients 65 years of age or older is less than 5%. 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. More importantly, with the understanding of molecular pathology of AML, personalized and targeted therapies are becoming an important part of the AML treatment armamentarium.

The pro-survival (anti-apoptotic) protein BCL2 is over expressed by AML cells and regulates clonal selection and cell survival. A new class of anticancer agents known as BH3-mimetic drugs mimic the activity of the physiologic antagonists of BCL2 and related proteins and promote apoptosis (programmed cell death). VENCLEXTA® (Venetoclax) is a second generation, oral, selective, small molecule inhibitor of BCL2 and restores the apoptotic processes in tumor cells. VIDAZA® (Azacitidine) is a hypomethylating agent that promotes DNA hypomethylation by inhibiting DNA methyltransferases. VIDAZA® has been shown to significantly improve Overall Survival (OS), when compared to conventional care regimens, in elderly unfit patients with newly diagnosed AML, who are not candidates for intensive chemotherapy. The combination of VIDAZA® and VENCLEXTA® in a previously published Phase Ib study was highly efficacious, with significant responses, duration of response and Overall Survival benefit.

VIALE-A is a Phase III, multicenter, randomized, double-blind, placebo-controlled confirmatory trial, conducted to evaluate the efficacy and safety of a combination of VIDAZA® and VENCLEXTA®, as compared with VIDAZA® plus placebo (the control regimen), in previously untreated patients with AML, who were ineligible for intensive induction therapy. In this study, 431 patients (N=431) with previously untreated AML were randomly assigned in a 2:1 ratio to receive either VIDAZA® plus VENCLEXTA® (N=286), or VIDAZA® plus placebo (N=145). Enrolled patients were ineligible for standard induction chemotherapy because of coexisting conditions, 75 years of age or older, or both. All patients received VIDAZA® 75 mg/m2 subcutaneously or IV on days 1 through 7 of every 28-day cycle. Patients in the study group also received VENCLEXTA® 100 mg orally on day 1 and 200 mg on day 2 and target dose of 400 mg on day 3, and continued daily until day 28 during cycle 1, to mitigate Tumor Lysis Syndrome. The dose of VENCLEXTA® was initiated at 400 mg daily in all subsequent 28-day cycles. In the control group, a matching placebo was administered orally, once daily, in 28-day cycles. The median age was 76 years in both groups, approximately 60% were male and 76% were Caucasian. Molecular abnormalities of interest included FLT-3, observed in 14% of patients receiving VIDAZA® plus VENCLEXTA®, IDH1/2, observed in 25% of patients, TP53, observed in 23.3% of patients and NPM1, observed in 16.6% of patients. Secondary AML was reported in 25% of the patients in the VIDAZA® plus VENCLEXTA® group and in 24% of the patients in the control group. All the patients were hospitalized on or before day 1 of cycle 1 and for at least 24 hours after receiving the final dose of VENCLEXTA®, in order to receive prophylaxis against the Tumor Lysis Syndrome and for monitoring. The Primary endpoint was Overall Survival (OS). The Secondary end points included Complete Remission (CR) rates, composite Complete Remission (Complete Remission or Complete Remission with incomplete hematologic recovery), RBC and platelet transfusion independence, and Quality of Life according to Patient-Reported Outcomes.

At a median follow up of 20.5 months, the median OS was 14.7 months in the VIDAZA® plus VENCLEXTA® group versus 9.6 months in the VIDAZA® plus placebo group (HR=0.66; P<0.001). VIDAZA® plus VENCLEXTA® combination resulted in a CR rate of 36.7% versus 17.9%; P<0.001 and composite CR of 66.4% versus 28.3%; P<0.001, when compared to the control regimen. Most responses were seen after the first 28-day cycle. The median time to first response was 1.3 versus and 2.8 months respectively, duration of CR was 17.5 months versus 13.3 months and median duration of composite CR was 17.5 months in the VIDAZA® plus VENCLEXTA® group and 13.4 months in the control group. RBC transfusion independence occurred in 59.8% of the patients in the VIDAZA® plus VENCLEXTA® group and in 35.2% of those in the control group (P<0.001), and platelet transfusion independence occurred in 68.5% and 49.7% (P<0.001), respectively. The benefits with VIDAZA® plus VENCLEXTA® were noted in almost all molecular subgroups compared to the control regimen. The response rates were highest among patients with FLT3 mutations (72.4% versus 36.4%, P=0.02) and those with IDH1 or IDH2 mutations (75.4 % versus 10.7%, P<0.001), respectively.

The researchers conducted 2 years of additional follow-up to determine the long-term survival benefit of VIDAZA® plus VENCLEXTA® combination and at this meeting reported the analysis of VIALE-A trial, after the occurrence of 100% of the pre-planned survival events. With a median follow-up of 43.2 months, the median Overall Survival (OS) benefit since the interim analysis in the overall population was maintained and was 14.7 months in the VIDAZA® plus VENCLEXTA® group versus 9.6 months in the VIDAZA® plus placebo group (HR=0.58; P<0.001). Among patients with Measurable Residual Disease (MRD) <10-3 who had achieved either Complete Remission (CR) or CR with incomplete hematologic recovery (CRi), the median OS was reached at 34.2 months in the VIDAZA® plus VENCLEXTA® group and 25.0 months in the control group. For patients in the IDH1/2 mutant subgroup, the median OS at final analysis with VIDAZA® plus VENCLEXTA® was 19.9 months and was 6.2 months in the control group (HR=0.31; P<0.001). Overall safety profiles were comparable between the treatment groups.

The 2-year follow up analysis of the VIALE-A trial confirmed the sustained Overall Survival benefit of VIDAZA® plus VENCLEXTA® combination in patients with AML, ineligible for intensive chemotherapy, with no new safety findings noted.

Long-Term Follow-up of the Phase 3 Viale-a Clinical Trial of Venetoclax Plus Azacitidine for Patients with Untreated Acute Myeloid Leukemia Ineligible for Intensive Chemotherapy. Pratz KW, Jonas BA, Pullarkat VA, et al. Presented at the 64th ASH Annual Meeting and Exposition, December 10-13, 2022, New Orleans, Louisiana. Abstract # 219

FDA Approves Quizartinib for Newly Diagnosed Acute Myeloid Leukemia

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SUMMARY: The FDA on July 20, 2023 approved Quizartinib (VANFLYTA®) with standard Cytarabine and Anthracycline induction and Cytarabine consolidation, and as maintenance monotherapy following consolidation chemotherapy, for the treatment of adult patients with newly diagnosed Acute Myeloid Leukemia (AML) that is FLT3 Internal Tandem Duplication (ITD)-positive, as detected by an FDA-approved test. FDA also approved LeukoStrat CDx FLT3 Mutation Assay as a companion diagnostic for Quizartinib.

The American Cancer Society estimates that in 2023, 20,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,310 patients will die of the disease. AML is one of the most common types of leukemia in adults and can be considered as a group of molecularly heterogeneous diseases with different clinical behavior and outcomes. A significant percentage of patients with newly diagnosed AML are not candidates for intensive chemotherapy, or have disease that is refractory to standard chemotherapy. Even with the best available therapies, the 5-year Overall Survival in patients 65 years of age or older is less than 5%. 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. More importantly, with the understanding of molecular pathology of AML, personalized and targeted therapies are becoming an important part of the AML treatment armamentarium.

The Fms-Like Tyrosine kinase 3 (FLT3) protein is a receptor tyrosine kinase in the PDGF family of growth factor receptors located on the hematopoietic stem cell surface (transmembrane). FLT3 normally promote cell survival, growth, and differentiation. FLT3 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. Approximately 25% of patients with newly diagnosed AML have FLT3-ITD mutations and approximately 7% have point mutations in the Tyrosine Kinase Domain (TKD). FLT3-ITD (Internal Tandem Duplication) mutation is 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 have poor outcomes with shorter remission duration and significantly decreased Leukemia Free and Overall Survival.

Quizartinib is an oral, highly potent, selective, Type 2 FLT3 inhibitor. This agent in combination with chemotherapy showed antitumor activity with an acceptable safety profile in patients with FLT3-ITD-positive newly diagnosed AML.

QuANTUM-First is a randomized, double-blind, placebo controlled, global, Phase III trial in which the efficacy of Quizartinib with chemotherapy was evaluated in patients with newly diagnosed FLT3-ITD positive AML aged 18–75 years. In this study, 539 patients (N=539) with newly diagnosed FLT3-ITD positive AML were randomly assigned 1:1 to receive chemotherapy plus Quizartinib (N=268) or placebo (N=271). Treatment consisted of induction with standard 7 plus 3 induction regimen of Cytarabine 100 mg/m2 daily (or 200 mg/m2 daily per institutional standard) by continuous IV from Days 1-7 and anthracycline (Daunorubicin 60 mg/m2 daily or Idarubicin 12 mg/m2 daily, by IV infusion on Days 1, 2, and 3, then Quizartinib 40 mg orally or placebo once daily, starting on day 8, for 14 days. Patients in complete remission or complete remission with incomplete neutrophil or platelet recovery received standard consolidation with high-dose Cytarabine plus Quizartinib (40 mg orally daily) or placebo, allo- Hematopoietic Stem Cell Transplantation (HSCT), or both as consolidation therapy, followed by continuation of single-agent Quizartinib or placebo for up to 3 years. There was no re-randomization at the initiation of post-consolidation therapy. Patients who proceeded to HSCT initiated maintenance therapy after HSCT recovery. FLT3-ITD status was determined prospectively with a clinical trial assay and verified retrospectively with the companion diagnostic LeukoStrat CDx FLT3 Mutation Assay. This study included patients aged 18 to 75 years, 55% male and 45% female, with newly diagnosed primary or secondary AML harboring a FLT3-ITD activating mutation, with an allelic ratio of 3% or more. The median age was 56 years. The aim of this study was to assess the effect of Quizartinib versus placebo on Overall Survival in patients with FLT3-ITD-positive newly diagnosed AML. The Primary end point of the trial was Overall Survival (OS). Secondary end points included Event-Free Survival (EFS), post induction rates of Complete Remission (CR) rate, composite CR (CRc) rate, Safety, and pharmacokinetics.

At a median follow up of 39.2 months, the median Overall Survival was 31.9 months for Quizartinib versus 15.1 months for placebo (HR=0.78; P=0.032), a 22% reduction in the risk of death. The CR rate in the Quizartinib group was 55%, with median response duration of 38.6 months, whereas the CR rate in those receiving placebo was 55% with median response duration of 12.4 months. Approximately 42% of patients treated with Quizartinib versus 38% treated with placebo were MRD negative at the time of Complete Remission or Complete Remission with incomplete neutrophil or platelet recovery. However, patients in both groups who were MRD negative had improved Overall Survival (HR 0.57), compared with those who remained MRD positive. The most common Grade 3 or 4 adverse events were febrile neutropenia, hypokalaemia, and pneumonia in both groups, and neutropenia in the Quizartinib group.

It was concluded that the addition of Quizartinib to standard chemotherapy with or without allo-HSCT, followed by continuation monotherapy for up to 3 years, resulted in improved Overall Survival in adults patients with FLT3-ITD-positive newly diagnosed AML, and provides a new, effective, and generally well tolerated treatment option for this patient group. The authors added that this is the first time a FLT3 inhibitor was studied in patients aged 18-75 years and is specifically approved for patients who have the worst FLT3 mutation, the ITD mutation.

Quizartinib plus chemotherapy in newly diagnosed patients with FLT3-internal-tandem-duplication-positive acute myeloid leukaemia (QuANTUM-First): a randomised, double-blind, placebo-controlled, phase 3 trial. Erba HP, Montesinos P, Kim H-J, et al. on behalf of the QuANTUM-First Study Group. The Lancet 2023;401:1571-1583.

Long Term Overall Survival Benefit with VIDAZA® plus VENCLEXTA® in Elderly AML Patients

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SUMMARY: The American Cancer Society estimates that in 2023, 20,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,310 patients will die of the disease. AML is one of the most common types of leukemia in adults and can be considered as a group of molecularly heterogeneous diseases with different clinical behavior and outcomes. A significant percentage of patients with newly diagnosed AML are not candidates for intensive chemotherapy or have disease that is refractory to standard chemotherapy. Even with the best available therapies, the 5-year Overall Survival in patients 65 years of age or older is less than 5%. 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. More importantly, with the understanding of molecular pathology of AML, personalized and targeted therapies are becoming an important part of the AML treatment armamentarium.

The pro-survival (anti-apoptotic) protein BCL2 is over expressed by AML cells and regulates clonal selection and cell survival. A new class of anticancer agents known as BH3-mimetic drugs mimic the activity of the physiologic antagonists of BCL2 and related proteins and promote apoptosis (programmed cell death). VENCLEXTA® (Venetoclax) is a second generation, oral, selective, small molecule inhibitor of BCL2 and restores the apoptotic processes in tumor cells. VIDAZA® (Azacitidine) is a hypomethylating agent that promotes DNA hypomethylation by inhibiting DNA methyltransferases. VIDAZA® has been shown to significantly improve Overall Survival (OS), when compared to conventional care regimens, in elderly unfit patients with newly diagnosed AML, who are not candidates for intensive chemotherapy. The combination of VIDAZA® and VENCLEXTA® in a previously published Phase Ib study was highly efficacious, with significant responses, duration of response and Overall Survival benefit.

VIALE-A is a Phase III, multicenter, randomized, double-blind, placebo-controlled confirmatory trial, conducted to evaluate the efficacy and safety of a combination of VIDAZA® and VENCLEXTA®, as compared with VIDAZA® plus placebo (the control regimen), in previously untreated patients with AML, who were ineligible for intensive induction therapy. In this study, 431 patients (N=431) with previously untreated AML were randomly assigned in a 2:1 ratio to receive either VIDAZA® plus VENCLEXTA® (N=286), or VIDAZA® plus placebo (N=145). Enrolled patients were ineligible for standard induction chemotherapy because of coexisting conditions, 75 years of age or older, or both. All patients received VIDAZA® 75 mg/m2 subcutaneously or IV on days 1 through 7 of every 28-day cycle. Patients in the study group also received VENCLEXTA® 100 mg orally on day 1 and 200 mg on day 2 and target dose of 400 mg on day 3, and continued daily until day 28 during cycle 1, to mitigate Tumor Lysis Syndrome. The dose of VENCLEXTA® was initiated at 400 mg daily in all subsequent 28-day cycles. In the control group, a matching placebo was administered orally, once daily, in 28-day cycles. The median age was 76 years in both groups, approximately 60% were male and 76% were Caucasian. Molecular abnormalities of interest included FLT-3, observed in 14% of patients receiving VIDAZA® plus VENCLEXTA®, IDH1/2, observed in 25% of patients, TP53, observed in 23.3% of patients and NPM1, observed in 16.6% of patients. Secondary AML was reported in 25% of the patients in the VIDAZA® plus VENCLEXTA® group and in 24% of the patients in the control group. All the patients were hospitalized on or before day 1 of cycle 1 and for at least 24 hours after receiving the final dose of VENCLEXTA®, in order to receive prophylaxis against the Tumor Lysis Syndrome and for monitoring. The Primary endpoint was Overall Survival (OS). The Secondary end points included Complete Remission (CR) rates, composite Complete Remission (Complete Remission or Complete Remission with incomplete hematologic recovery), RBC and platelet transfusion independence, and Quality of Life according to Patient-Reported Outcomes.

At a median follow up of 20.5 months, the median OS was 14.7 months in the VIDAZA® plus VENCLEXTA® group versus 9.6 months in the VIDAZA® plus placebo group (HR=0.66; P<0.001). VIDAZA® plus VENCLEXTA® combination resulted in a CR rate of 36.7% versus 17.9%; P<0.001 and composite CR of 66.4% versus 28.3%; P<0.001, when compared to the control regimen. Most responses were seen after the first 28-day cycle. The median time to first response was 1.3 versus and 2.8 months respectively, duration of CR was 17.5 months versus 13.3 months and median duration of composite CR was 17.5 months in the VIDAZA® plus VENCLEXTA® group and 13.4 months in the control group. RBC transfusion independence occurred in 59.8% of the patients in the VIDAZA® plus VENCLEXTA® group and in 35.2% of those in the control group (P<0.001), and platelet transfusion independence occurred in 68.5% and 49.7% (P<0.001), respectively. The benefits with VIDAZA® plus VENCLEXTA® were noted in almost all molecular subgroups compared to the control regimen. The response rates were highest among patients with FLT3 mutations (72.4% versus 36.4%, P=0.02) and those with IDH1 or IDH2 mutations (75.4 % versus 10.7%, P<0.001), respectively.

The researchers conducted 2 years of additional follow-up to determine the long-term survival benefit of VIDAZA® plus VENCLEXTA® combination and at this meeting reported the analysis of VIALE-A trial, after the occurrence of 100% of the pre-planned survival events. With a median follow-up of 43.2 months, the median Overall Survival (OS) benefit since the interim analysis in the overall population was maintained and was 14.7 months in the VIDAZA® plus VENCLEXTA® group versus 9.6 months in the VIDAZA® plus placebo group (HR=0.58; P<0.001). Among patients with Measurable Residual Disease (MRD) <10-3 who had achieved either Complete Remission (CR) or CR with incomplete hematologic recovery (CRi), the median OS was reached at 34.2 months in the VIDAZA® plus VENCLEXTA® group and 25.0 months in the control group. For patients in the IDH1/2 mutant subgroup, the median OS at final analysis with VIDAZA® plus VENCLEXTA® was 19.9 months and was 6.2 months in the control group (HR=0.31; P<0.001). Overall safety profiles were comparable between the treatment groups.

The 2-year follow up analysis of the VIALE-A trial confirmed the sustained Overall Survival benefit of VIDAZA® plus VENCLEXTA® combination in patients with AML, ineligible for intensive chemotherapy, with no new safety findings noted.

Long-Term Follow-up of the Phase 3 Viale-a Clinical Trial of Venetoclax Plus Azacitidine for Patients with Untreated Acute Myeloid Leukemia Ineligible for Intensive Chemotherapy. Pratz KW, Jonas BA, Pullarkat VA, et al. Presented at the 64th ASH Annual Meeting and Exposition, December 10-13, 2022, New Orleans, Louisiana. Abstract # 219

Sequential Conditioning and Allogeneic Hematopoietic Cell Transplantation WITHOUT Prior Remission-Induction Chemotherapy in AML

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SUMMARY: The American Cancer Society estimates that for 2023, about 20,380 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,310 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.

Cytotoxic chemotherapy for AML often consists of induction therapy to achieve remission, followed by consolidation therapy. However, standard induction chemotherapy achieves Complete Remission in only 40-60% of AML patients older than 60 years of age, and majority of these patients will eventually relapse. This had been attributed to clonal evolution and epigenetic reprogramming, leading to aberrant DNA methylation, and persistence of leukemia-initiating cells. Patients with AML who are under age 55 with high-risk cytogenetics in first clinical remission, are considered for allogeneic Hematopoietic Cell Transplantation, as this has shown to offer survival advantage over conventional chemotherapy. Patients receive salvage chemotherapy, targeted therapy for FLT3-mutant and susceptible IDH mutant AML, or treatment with a BCL2 inhibitor and hypomethylating agent, if a donor is not readily available and a prolonged donor search is needed.

ASAP is a randomized Phase III trial, conducted in patients with an unfavorable risk AML who either had a poor response to first induction therapy or had a relapse after first induction therapy. This study enrolled AML patients with poor response after first induction therapy or relapsed AML, who were eligible for intensive chemotherapy and allogeneic Hematopoietic Cell Transplantation with either a matched sibling donor, an HLA-compatible (9 or more/10) unrelated donor, or ongoing donor search with two potential unrelated donors with 90% or more HLA-matching probability. This analysis included 276 patients, of whom 272 patients were treated per protocol. Patients were randomized 1:1 to a Remission Induction arm in which patients received Cytarabine 3 g/m2 IV (1 g/m2 for patients more than 60 years) twice daily on days 1-3 plus Mitoxantrone 10 mg/m2 IV on days 3-5 and subsequent allogeneic Hematopoietic Cell Transplantation (Remission Induction Strategy arm-N=134) or to Disease Control arm (DISC arm-N=138) prior to sequential conditioning and allogeneic Hematopoietic Cell Transplantation. Disease Control Strategy consisted primarily of watchful waiting, but low-dose Cytarabine and single doses of mitoxantrone were permitted for disease-control. The median age was 61 years and at randomization, 39 patients had matched sibling donor, 133 patients had an HLA-compatible unrelated donor with confirmed HLA-typing, and 104 patients had ongoing unrelated donor searches. The Primary endpoint was Disease Free Survival (DFS), defined as Complete Remission at day 56 after allogeneic Hematopoietic Cell Transplantation, although the statistical goal of the study was to show non-inferiority of the Disease Control arm. Major secondary endpoints included Overall Survival (OS) from randomization and Leukemia-Free Survival from Complete Remission at day 56. The median time to allogeneic Hematopoietic Cell Transplantation was 8 weeks in the Remission Induction Strategy arm and 4 weeks in the Disease Control arm. At 24 weeks from randomization 96% and 94% of patients had been transplanted in the Remission Induction Strategy arm and Disease Control arm, respectively.

The Primary endpoint was met with the Disease Control arm, which is the less intensive treatment strategy, meeting the Primary endpoint of DFS/Complete Remission at day 56 after allogeneic Hematopoietic Cell Transplantation. The Disease-Free Survival at day 56 was 81.3% in the Remission Induction Strategy arm and 84.1% in the Disease Control arm (P for noninferiority=0.047). Among patients who met the Primary endpoint, after a median follow-up from randomization of 37 months, there was no significant difference in the Leukemia-Free Survival or Overall Survival from day 56, in the Remission Induction Strategy arm and Disease Control arm. The Disease Control Strategy was also associated with significantly fewer Grade 3 or more adverse events, compared to the Remission Induction Strategy (23% versus 64%, P<0.001), and fewer mean number of days in hospital prior to transplant (19 versus 42 days, P<0.001).

The researchers concluded from this first randomized controlled trial that intensive remission induction chemotherapy prior to allogeneic Hematopoietic Cell Transplantation for patients with Relapsed/Refractory AML DID NOT result in a higher overall success rate and did not confer a survival advantage. It was noted that watchful waiting followed by sequential conditioning and allogeneic Hematopoietic Cell Transplantation resulted in comparable overall Complete Remission rates and survival. The researchers added that the data from this study support sequential conditioning and Hematopoietic Cell Transplantation, without prior remission-induction chemotherapy, whenever a donor is readily available. Further, the results of this study emphasize the importance of allogeneic Hematopoietic Cell Transplantation in patients with Relapsed/Refractory AML and stress the need for starting donor search at diagnosis.

In Patients with Relapsed/Refractory AML Sequential Conditioning and Immediate Allogeneic Stem Cell Transplantation (allo-HCT) Results in Similar Overall and Leukemia-Free Survival Compared to Intensive Remission Induction Chemotherapy Followed By Allo-HCT: Results from the Randomized Phase III ASAP Trial. Stelljes M, Middeke JM, Bug G, et al. 64th ASH Annual Meeting and Exposition December 10th-13,2022. Abstract#4.

FDA Approves REZLIDHIA® for Acute Myeloid Leukemia

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SUMMARY: The FDA on December 1, 2022, approved REZLIDHIA® (Olutasidenib) capsules for adult patients with Relapsed or Refractory Acute Myeloid Leukemia (AML) with a susceptible IDH1 mutation, as detected by an FDA-approved test. The FDA on the same day also approved the Abbott RealTime IDH1 Assay to select patients for REZLIDHIA®.

The American Cancer Society estimates that for 2022, about 20,050 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,540 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. AML mainly affects older adults and the median age at diagnosis is 68 years. A significant majority of patients with AML are unable to receive intensive induction chemotherapy due to comorbidities and therefore receive less intensive, noncurative regimens, with poor outcomes.

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 can thus promote leukemogenesis in Acute Myeloid Leukemia and tumorigenesis in solid tumors and can result in inferior outcomes. 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 20-25% 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. IDH2 mutations are more common than IDH1 mutations, occurring in approximately 15% to 20% of patients with AML. The presence of IDH mutations has both prognostic and predictive value. Patients with an IDH mutation and a Nucleo¬phosmin (NPM1) mutation usually have a better prognosis whereas patients with mutations in IDH and FMS-like tyrosine kinase 3 (FLT3) do not. Further IDH mutations predict response to specific IDH1 and IDH2 inhibitors in the Relapsed and Refractory setting. The presence of an IDH mutation is therefore not only prognostic, but also predictive of response to certain therapies.

The two IDH inhibitors presently available in the US include IDHIFA® (Enasidenib), approved for the treatment of patients with Relapsed or Refractory AML with IDH2 mutation and TIBSOVO® (Ivosidenib), approved for AML patients with the IDH1 mutation who have Relapsed/Refractory disease, as well as monotherapy for newly diagnosed AML patients 75 years or older with comorbidities that preclude the use of intensive induction chemotherapy. IDHIFA® can be associated with indirect hyperbilirubinemia, which is of no clinical consequence, whereas with TIBSOVO® there is a small risk of QT interval prolongation. Both agents can lead to Differentiation Syndrome in 10-15% of patients which requires systemic steroids and hemodynamic monitoring for at least 3 days.

REZLIDHIA® is a potent, selective, oral, brain-penetrant, small molecule inhibitor of mutant IDH1, that has exhibited favorable tolerability and clinical activity in high-risk AML patients in a Phase 1 trial (Watts JM, et al. Blood 2019). The present FDA approval was based on the Phase 1/2 Study 2102-HEM-101 trial (NCT02719574), which included 147 adult patients with Relapsed or Refractory AML with an IDH1 mutation, confirmed using the above now approved assay. Enrolled patients had pathologically proven AML, except those with Acute Promyelocytic Leukemia with the t(15;17) translocation, or intermediate high, or very high-risk MDS as defined by the WHO criteria or Revised International Prognostic Scoring System. REZLIDHIA® 150 mg was given orally, twice daily, until disease progression, unacceptable toxicity, or Hematopoietic Stem Cell Transplantation. The median treatment duration was 4.7 months. Sixteen (11%) patients underwent Hematopoietic Stem Cell Transplantation following treatment with REZLIDHIA®. The Primary end points included the rate of Complete Remission (CR) plus Complete Remission with partial hematologic recovery (CRh). Secondary end points included time to response, Duration of Response, Event-Free Survival, Overall Survival, and Relapse-Free Survival.

The Complete Remission plus Complete Remission with partial hematologic recovery rate with REZLIDHIA® was 35%, with 32% CR and 2.7% CRh. The median time to CR+CRh was 1.9 months and the median duration of CR+CRh was 25.9 months. Among the 86 patients who were Red Blood Cell (RBC) and/or platelet transfusions dependent at baseline, 34% became RBC and platelet transfusion independent during any 56-day post-baseline period. Of the 61 patients who were RBC and platelet transfusions independent at baseline, 64% remained transfusion independent during any 56-day post-baseline period. The most common adverse reactions were nausea, diarrhea, constipation, mucositis, fatigue/malaise, arthralgia, fever, rash, leukocytosis, dyspnea, and transaminitis. Health care professionals and patients should be aware of the risk of Differentiation Syndrome, which can be fatal.

REZLIDHIA® is the third IDH inhibitor currently approved for the treatment of Acute Myeloid Leukemia.

https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-olutasidenib-relapsed-or-refractory-acute-myeloid-leukemia-susceptible-idh1-mutation.

TIBSOVO® and VIDAZA® Combo Improve Survival in IDH1-Mutated Acute Myeloid Leukemia

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SUMMARY: The American Cancer Society estimates that for 2022, about 20,050 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,540 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. AML mainly affects older adults and the median age at diagnosis is 68 years. A significant majority of patients with AML are unable to receive intensive induction chemotherapy due to comorbidities and therefore receive less intensive, noncurative regimens, with poor outcomes.

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 can thus promote leukemogenesis in Acute Myeloid Leukemia and tumorigenesis in solid tumors and can result in inferior outcomes. 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.MOA-of-Ivosidenib

TIBSOVO® (Ivosidenib) is a first-in-class, oral, potent, targeted, small-molecule inhibitor of mutant IDH1. The FDA in 2018, approved TIBSOVO® for adult patients with relapsed or refractory AML with a susceptible IDH1 mutation and in 2019 approved TIBSOVO® for newly diagnosed AML with a susceptible IDH1 (Isocitrate DeHydrogenase-1) mutation, in patients who are at least 75 years old or who have comorbidities that preclude the use of intensive induction chemotherapy. VIDAZA® (Azacitidine) is a hypomethylating agent that promotes DNA hypomethylation by inhibiting DNA methyltransferases. VIDAZA® has been shown to significantly improve Overall Survival (OS) when compared to conventional care regimens in elderly unfit patients with newly diagnosed AML, who are not candidates for intensive chemotherapy. In a Phase Ib trial, TIBSOVO® in combination with VIDAZA® showed encouraging clinical activity in newly diagnosed IDH1-mutated AML patients.

AGILE is a global, double-blind, randomized, placebo-controlled, Phase III trial in which the efficacy and safety of a combination of TIBSOVO® and VIDAZA® were assessed, as compared with placebo and VIDAZA®, in patients with newly diagnosed IDH1-mutated Acute Myeloid Leukemia, who were ineligible for intensive induction chemotherapy. Patients were randomly assigned in a 1:1 ratio to receive TIBSOVO® 500 mg orally once daily combined with VIDAZA® 75 mg/m2 subcutaneously or IV for 7 days in 28-day cycles (N=72) or placebo and VIDAZA® (N=74). All the patients were to be treated for a minimum of six cycles until disease progression or unacceptable toxicities. The median patient age was 76 years, 75% had primary AML and 25% had secondary AML, 67% had intermediate cytogenetic risk and 22% had poor cytogenetic risk. Patients were stratified according to geographic region and disease status (Primary versus Secondary Acute Myeloid Leukemia). The Primary end point was Event-Free Survival, defined as the time from randomization until treatment failure (failure of complete remission by week 24), relapse from remission, or death from any cause, whichever occurred first.

At a median follow-up of 12.4 months, Event-Free Survival was significantly longer in the TIBSOVO® and VIDAZA® group than in the placebo and VIDAZA® group (HR=0.33; P=0.002). This benefit was seen across all key subgroups. The estimated probability that a patient would remain event-free at 12 months was 37% in the TIBSOVO® and VIDAZA® group and 12% in the placebo and VIDAZA® group. The median Overall Survival was 24.0 months with TIBSOVO® and VIDAZA® and 7.9 months with placebo and VIDAZA® (HR=0.44; P=0.001). Among those patients who were dependent on transfusion of red blood cells, platelets, or both at baseline, a higher percentage of patients converted to transfusion independence with TIBSOVO® and VIDAZA®, than with placebo and VIDAZA® (46% versus 18%; P=0.006). Health-Related Quality of Life scores favored TIBSOVO® and VIDAZA® across all subscales. Grade 3 or higher Adverse Events included febrile neutropenia (28% with TIBSOVO® and VIDAZA® versus 34% with placebo and VIDAZA®) and neutropenia (27% versus 16%, respectively). Differentiation syndrome of any grade occurred in 14% of the patients receiving TIBSOVO® and VIDAZA® versus 8% among those receiving placebo and VIDAZA®.

It was concluded that a combination of TIBSOVO® and VIDAZA® significantly improved Event-Free Survival, Response Rates, and Overall Survival, as compared with placebo and VIDAZA®, in patients with newly diagnosed IDH1-mutated Acute Myeloid Leukemia, who were ineligible for induction chemotherapy. The authors added that treatment with TIBSOVO® and VIDAZA® resulted in better Quality of Life and higher rates of transfusion independence.

Ivosidenib and Azacitidine in IDH1-Mutated Acute Myeloid Leukemia. Montesinos P, Recher C, Vives S, et al. N Engl J Med 2022; 386:1519-1531.