Nilotinib-induced bone marrow aplasia

Stem cell allografting for chronic Myeloid leukemia in the tyrosine kinase era - forgotten but not gone

Due to the remarkable success of tyrosine kinase inhibitors (TKI) in chronic myeloid leukemia (CML), allogeneic stem cell transplantation (alloSCT) is not first-line treatment for delivering durable, long-term survival. Consequently, alloSCT is reserved for patients with TKI-resistant or TKI-intolerant chronic phase CML (CP-CML) and advanced phase CML (AP-CML). Advances in transplant technology, such as high-resolution HLA typing, introduction of reduced intensity conditioning and increased alternative donor availability, coupled with improved supportive care, have significantly reduced transplant-related mortality and expanded the pool of transplant-eligible patients. Refinement of conditioning regimens, innovative use of post-transplant cellular and pharmacological therapies, and judicious post-transplant monitoring are important strategies for reducing risk of relapse. Given its potential to cure, alloSCT will invariably remain a key part of the treatment algorithm. This article reviews the data underpinning the role and outcomes of alloSCT and provides an update on current recommendations.

Postmarketing Safety of Sacituzumab Govitecan: A Pharmacovigilance Study Based on the FDA Adverse Event Reporting System

Sacituzumab govitecan is widely used for the treatment of breast cancer and urothelial carcinoma, but available information regarding adverse events (AEs) is limited. We aim to explore the AE induced by sacituzumab govitecan by mining the FDA Adverse Event Reporting System (FAERS) database. The association between sacituzumab govitecan and AEs was evaluated using the information component. A multivariate logistic regression analysis was conducted for all identified signals to explore the risk factors associated with AEs leading to hospitalization. In total, 1,884 reports related to sacituzumab govitecan were retrieved, and 114 AE signals involving 20 systems were identified. The median time for onset of AEs was ~ 6-7 days after initiating treatment with sacituzumab govitecan, with over 80% of AEs occurring within 30 days. Subgroup analysis revealed that 14 signals were reported in men and 110 in women. There were 58 signals reported in patients under 65 following the use of sacituzumab govitecan, 59 signals in patients over 65, and 31 signals were present in both groups. Multivariable analysis showed that being male and the occurrence of colitis, pneumonitis, febrile neutropenia, pyrexia, sepsis, dehydration, and diarrhea were risk factors leading to hospitalization with an area under the curve (AUC) of 0.89. Additionally, sensitivity analysis revealed that this study had good robustness. This is the first retrospective analysis based on FAERS to review the safety of sacituzumab govitecan. The results highlight the need to closely monitor adverse reactions such as neutropenia, diarrhea, colitis, and sepsis when using sacituzumab govitecan.

Aplastic anemia secondary to tyrosine kinase inhibitor therapy in a patient with chronic myeloid leukemia

INTRODUCTION

Nilotinib, as the second generation of tyrosine kinase inhibitor, has significant efficacy in patients with chronic myeloid leukemia resistant or intolerant to Imatinib. Aplastic anemia induced by tyrosine kinase inhibitors is an uncommon complication.

CASE REPORT

A 34-year-old female case with CML in the chronic phase was treated with Imatinib in first-line therapy. Nilotinib was switched because of failure to achieve complete cytogenetic response at 6 months following Imatinib. Three years with Nilotinib, the patient developed a persistent pancytopenia grade 4 while a major molecular response was achieved.

MANAGEMENT & OUTCOME

Nilotinib was discontinued. However, the hematologic finding of the patient had not recovered after three months. A bone marrow biopsy showed marked hypocellularity and fatty tissue without evidence of myelofibrosis. Immunosuppressive therapy was started. Unfortunately, the patient died due to septic and hemorrhagic shock nine months after Nilotinib interruption. According to Naranjo's algorithm, the causality relationship with the drug is probable with a score of 5.

DISCUSSION

Aplastic anemia is an uncommon adverse event of tyrosine kinase inhibitors but it can be a fatal complication. The early diagnosis of aplastic anemia related to Nilotinib therapy is needed to avoid further detrimental effects of the drug.

A Case of Tyrosine Kinase Inhibitor-Induced Bone Marrow Aplasia That Was Successfully Treated with Allogeneic Hematopoietic Stem Cell Transplantation

Here, we present a rare case of tyrosine kinase inhibitor (TKI)-induced bone marrow aplasia. A 58-year-old man presented with leukocytosis and was diagnosed with chronic myeloid leukemia. He was initially treated with imatinib for 6 years and abruptly discontinued treatment by himself. He was administered dasatinib 5 years after treatment interruption, and presented with pancytopenia 6 months after dasatinib initiation. Bone marrow biopsy revealed severe hypocellularity without blasts. Dasatinib was discontinued, and he recovered from pancytopenia 3 months later; however, BCR-ABL1 was positive for almost all white blood cells in the peripheral blood. We retreated with ponatinib, but pancytopenia developed again. The clinical course indicated TKI-induced bone marrow aplasia. Therefore, ponatinib was discontinued and the patient received an allogeneic hematopoietic stem cell transplantation from a haploidentical daughter using post-transplant cyclophosphamide. He had a major molecular response and had normal complete blood counts and bone marrow 1 year after transplantation.

Unexpected pancytopenia: Dasatinib induced aplastic anemia in chronic myeloid leukemia

INTRODUCTION

The use of TKIs in CML has dramatically altered the natural course of the disease and improved outcomes for patients. TKIs overall have a very favorable safety profile. Dasatinib, a second generation TKI, is commonly used as a first-line treatment option in CML.

CASE REPORT

We describe the first two reported cases of first-line dasatinib induced aplastic anemia in CML. In both patients, pancytopenia occurred within one year of diagnosis/starting dasatinib. Both bone marrow biopsies showed hypocellularity with mild fibrosis and persistent BCR-Abl1 positivity.

MANAGEMENT & OUTCOME

Dose reduction was attempted without success in both patients. In one patient, multiple TKIs were trialed, while in the other, growth factor support was attempted; neither regimen was effective. Ultimately, the cytopenias associated with dasatinib were only resolved after immunosuppression in one patient and allogeneic stem cell transplant in the other patient.

DISCUSSION

Prior reports have shown that aplasia/aplastic anemia can rarely be associated with imatinib and nilotinib. Here we show that dasatinib can lead to this phenomenon as well. This diagnosis should be considered in patients with CML who unexpectedly develop cytopenias.

Aplasia in Chronic Phase CML Post-TKI Therapy: A Management Dilemma

Transient cytopenias and bone marrow hypoplasia commonly occur during treatment of CML with TKIs (tyrosine kinase inhibitors). This is usually related to the eradication of CML clones that initially compose the majority of hematopoietic cells in the bone marrow at the time of diagnosis. With continuation of effective therapy, normal blood counts return as normal hematopoiesis is restored and CML clones are reduced. Though rare and more unusual than myelodysplastic syndrome (MDS), isolated instances of persistent marrow aplasia have been documented with chronic use of TKIs. We describe two such instances of chronic phase CML where no significant reduction of CML clones was achieved following treatment with TKIs, but bone marrow aplasia occurred resulting in persistent dysfunctional hematopoiesis. Due to prolonged aplasia/hypoplasia, such patients are no longer amenable to TKI treatment. CML progression to accelerated or blast phase in that setting would likely be fatal.

Recurrent bone marrow aplasia secondary to nilotinib in a patient with chronic myeloid leukemia: A case report

Nilotinib is a potent tyrosine kinase inhibitor of breakpoint cluster region-abelson (BCR-ABL), which has been approved as front-line therapy for newly diagnosed chronic myeloid leukemia in chronic phase and as second-line therapy after imatinib failure in chronic or accelerated phase chronic myeloid leukemia. Tyrosine kinase inhibitors have been associated with myelosuppression and grade 3 or grade 4 cytopenias are not uncommon in chronic myeloid leukemia patients treated with these drugs. There are a few reports of imatinib-associated bone marrow aplasia, but to our knowledge only one reported case of bone marrow aplasia associated with nilotinib. Herein, we report a 49-year-old male patient with chronic phase chronic myeloid leukemia, who developed severe bone marrow aplasia due to nilotinib. Possible mechanisms for this significant adverse drug reaction are discussed along with a review of literature.

Hematologic toxicities of small molecule tyrosine kinase inhibitors

Small molecule tyrosine kinase inhibitors (TKIs) are potent anti-cancer targeted therapies. TKIs are considered safe and efficacious therapeutic modalities, and are generally tolerated well. However, they are associated with certain side effects including hematologic toxicities such as anemia, macrocytosis, neutropenia, thrombocytopenia, hemolytic anemia, bone marrow aplasia and necrosis. Thrombotic microangiopathy, arterial thromboembolism and splenic infarction can also occur following treatment with TKIs. Cytopenias are the most common adverse effects associated with these agents, and other hematologic toxicities are not frequent. It is essential for clinicians to monitor patients closely, and recognize those side effects as early as possible, in order to improve efficacy of small molecule TKIs and optimize outcomes. This article summarizes hematologic toxicities associated with the commonly used small molecule TKIs. It also provides practical strategies for the management of these toxicities.