Thrombotic microangiopathy: a new dose-limiting toxicity of high-dose sequential chemotherapy

A pharmacovigilance study of etoposide in the FDA adverse event reporting system (FAERS) database, what does the real world say?

Introduction: Etoposide is a broad-spectrum antitumor drug that has been extensively studied in clinical trials. However, limited information is available regarding its real-world adverse reactions. Therefore, this study aimed to assess and evaluate etoposide-related adverse events in a real-world setting by using data mining method on the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database. Methods: Through the analysis of 16,134,686 reports in the FAERS database, a total of 9,892 reports of etoposide-related adverse drug events (ADEs) were identified. To determine the significance of these ADEs, various disproportionality analysis algorithms were applied, including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) algorithms. Results: As a result, 478 significant disproportionality preferred terms (PTs) that were identified by all four algorithms were retained. These PTs included commonly reported adverse events such as thrombocytopenia, leukopenia, anemia, stomatitis, and pneumonitis, which align with those documented in the drug's instructions and previous clinical trials. However, our analysis also uncovered unexpected and significant ADEs, including thrombotic microangiopathy, ototoxicity, second primary malignancy, nephropathy toxic, and ovarian failure. Furthermore, we examined the time-to-onset (TTO) of these ADEs using the Weibull distribution test and found that the median TTO for etoposide-associated ADEs was 10 days (interquartile range [IQR] 2-32 days). The majority of cases occurred within the first month (73.8%) after etoposide administration. Additionally, our analysis revealed specific high-risk signals for males, such as pneumonia and cardiac infarction, while females showed signals for drug resistance and ototoxicity. Discussion: These findings provide valuable insight into the occurrence of ADEs following etoposide initiation, which can potentially support clinical monitoring and risk identification efforts.

Delayed Development of Hemolytic Anemia with Fragmented Red Blood Cells and Cardiac and Renal Impairments after High-Dose Chemotherapy and Autologous Hematopoietic Stem Cell Transplantation for Malignant Lymphoma

Among 42 consecutive patients with malignant lymphoma who underwent high-dose chemotherapy (HDC) followed by autologous hematopoietic stem cell transplantation (AHSCT), 5 developed hemolytic anemia with fragmented red blood cells (HA-FrRBCs) on days 87-125 (median 107) of AHSCT. Nadir Hb levels ranged between 5.0 and 6.4 g/dL with 2.2-5.6% FrRBCs. All patients developed grade ≥3 hypoxia and heart failure, and 4 developed grade ≥3 hypertension. The ejection fraction of the left ventricle assessed by echocardiography was significantly reduced in 3 patients. Peak creatinine levels were >4 times above the baseline and estimated glomerular filtration rates were reduced to <30 mL/min/1.73 m2. One patient received plasma exchange, while the remaining 4 responded to treatment with diuretics and cardiovascular agents. Hematological parameters normalized within a median duration of 91 days after the development of HA-FrRBCs. Renal and cardiac functions gradually improved, even though renal function did not return to the baseline. HA-FrRBCs associated with cardiac and renal impairments may represent a thrombotic microangiopathy syndrome and are a delayed complication of HDC/AHSCT. The close monitoring of laboratory abnormalities and persistent treatment with cardiovascular agents and diuretics are the mainstay for the management of this condition.

Antineoplastic agents and thrombotic microangiopathy

Thrombotic microangiopathy is an uncommon but reported adverse effect of a variety of antineoplastic drugs, including chemotherapy agents such as mitomycin C and gemcitabine, and newer targeted agents such as the vascular endothelial growth factor inhibitors. We present a review of thrombotic microangiopathy associated with antineoplastic agents and its implications in current cancer therapy.

Anti-Neoplastic Cytotoxicity of Gemcitabine-(C4-amide)-[anti-EGFR] in Dual-combination with Epirubicin-(C3-amide)-[anti-HER2/neu] against Chemotherapeutic-Resistant Mammary Adenocarcinoma (SKBr-3) and the Complementary Effect of Mebendazole

AIMS

Delineate the feasibility of simultaneous, dual selective "targeted" chemotherapeutic delivery and determine if this molecular strategy can promote higher levels anti-neoplastic cytotoxicity than if only one covalent immunochemotherapeutic is selectively "targeted" for delivery at a single membrane associated receptor over-expressed by chemotherapeutic-resistant mammary adenocarcinoma.

METHODOLOGY

Gemcitabine and epirubicin were covalently bond to anti-EGFR and anti-HER2/neu utilizing a rapid multi-phase synthetic organic chemistry reaction scheme. Determination that 96% or greater gemcitabine or epirubicin content was covalently bond to immunoglobulin fractions following size separation by micro-scale column chromatography was established by methanol precipitation analysis. Residual binding-avidity of gemcitabine-(C4-amide)-[anti-EG-FR] applied in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu] was determined by cell-ELIZA utilizing chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) populations. Lack of fragmentation or polymerization was validated by SDS-PAGE/immunodetection/chemiluminescent autoradiography. Anti-neoplastic cytotoxic potency was determined by vitality stain analysis of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) monolayers known to uniquely over-express EGFR (2 × 105/cell) and HER2/neu (1 × 106/cell) receptor complexes. The covalent immunochemotherapeutics gemcitabine-(C4-amide)-[anti-EGFR] and epirubicin-(C3-amide)-[anti-HER2/neu] were applied simultaneously in dual-combination to determine their capacity to collectively evoke elevated levels of anti-neoplastic cytotoxicity. Lastly, the tubulin/microtubule inhibitor mebendazole evaluated to determine if it's potential to complemented the anti-neoplastic cytotoxic properties of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu].

RESULTS

Dual-combination of gemcitabine-(C4-amide)-[anti-EGFR] with epirubicin-(C3-amide)-[anti-HER2/neu] produced greater levels of anti-neoplastic cytotoxicity than either of the covalent immunochemotherapeutics alone. The benzimidazole microtubule/tubulin inhibitor, mebendazole complemented the anti-neoplastic cytotoxicity of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu].

CONCLUSIONS

The dual-combination of gemcitabine-(C4-amide)-[anti-EGFR] with epirubicin-(C3-amide)-[anti-HER2/neu] produced higher levels of selectively "targeted" anti-neoplastic cytotoxicity against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) than either covalent immunochemotherapeutic alone. The benzimidazole tubulin/microtubule inhibitor, mebendazole also possessed anti-neoplastic cytotoxicity against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) and complemented the potency and efficacy of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu].

Kidney complications of hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) exposes a patient's kidneys to a unique combination of challenges, including high-dose radiation, anemia, chemotherapeutic agents, graft-versus-host disease, opportunistic infections, attenuated and altered immunologic responses, fluid and electrolyte imbalances, and extensive courses of antimicrobial agents. Since the inception of HSCT in the 1950s, there has been increasing interest in defining, determining, and managing the kidney complications that accompany this procedure. In this article, we review the common causes of acute kidney injury and chronic kidney disease that occur with HSCT, including HSCT-associated thrombotic microangiopathy, a distinct cause of chronic kidney disease with a multifactorial cause previously known as bone marrow transplant nephropathy or radiation nephropathy. Additionally, we review other kidney complications, including calcineurin inhibitor nephrotoxicity and chronic graft-versus-host disease-associated glomerulonephritis, that develop post-HSCT. Critically, due to its grave prognosis, it is important to identify HSCT-associated thrombotic microangiopathy early, as well as distinguish it from the other causes of chronic kidney disease.

Influence of Alternative Tubulin Inhibitors on the Potency of a Epirubicin-Immunochemotherapeutic Synthesized with an Ultra Violet Light-Activated Intermediate: Influence of incorporating an internal/integral disulfide bond structure and Alternative Tubulin/Microtubule Inhibitors on the Cytotoxic Anti-Neoplastic Potency of Epirubicin-(C3-amide)-Anti-HER2/neu Synthesized Utilizing a UV-Photoactivated Anthracycline Intermediate

Immunochemotherapeutics, epirubicin-(C₃-amide)-SS-[anti-HER2/neu] with an internal disulfide bond, and epirubicin-(C₃-amide)-[anti-HER2/neu] were synthesized utilizing succinimidyl 2-[(4,4'-azipentanamido) ethyl]-1,3'-dithioproprionate or succinimidyl 4,4-azipentanoate respectively. Western blot analysis was used to determine the presence of any immunoglobulin fragmentation or IgG-IgG polymerization. Retained HER2/neu binding characteristics of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] were validated by cell-ELISA using a mammary adenocarcinoma (SKBr-3) population that highly over-expresses trophic HER2/neu receptor complexes. Cytotoxic anti-neoplastic potency of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] between epirubicin-equivalent concentrations of 10^-10 M and 10^-6 M was determined by measuring the vitality/proliferation of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3 cell type). Cytotoxic anti-neoplastic potency of benzimidazoles (albendazole, flubendazole, membendazole) and griseofulvin were assessed between 0-to-2 μg/ml and 0-to-100 μg/ml respectively while mebendazole and griseofulvin were analyzed at fixed concentrations of 0.35 μg/ml and 35 g/ml respectively in dual combination with gradient concentrations of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu]. Cytotoxic anti-neoplastic potency for epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) was nearly identical at epirubicin-equivalent concentrations of 10^-10 M and 10^-6 M. The benzimadazoles also possessed cytotoxic anti-neoplastic activity with flubendazole and albendazole being the most and least potent respectively. Similarly, griseofulvin had cytotoxic anti-neoplastic activity and was more potent than methylselenocysteine. Both mebendazole and griseofulvin when applied in dual combination with either epirubicin-(C₃-amide)-[anti-HER2/neu] or epirubicin-(C₃-amide)-SS-[anti-HER2/neu] produced enhanced levels of cytotoxic anti-neoplatic potency.

Acute renal endothelial injury during marrow recovery in a cohort of combined kidney and bone marrow allografts

An idiopathic capillary leak syndrome ('engraftment syndrome') often occurs in recipients of hematopoietic cells, manifested clinically by transient azotemia and sometimes fever and fluid retention. Here, we report the renal pathology in 10 recipients of combined bone marrow and kidney allografts. Nine developed graft dysfunction on day 10-16 and renal biopsies showed marked acute tubular injury, with interstitial edema, hemorrhage and capillary congestion, with little or no interstitial infiltrate (≤10%) and marked glomerular and peritubular capillary (PTC) endothelial injury and loss by electron microscopy. Two had transient arterial endothelial inflammation; and 2 had C4d deposition. The cells in capillaries were primarily CD68(+) MPO(+) mononuclear cells and CD3(+) CD8(+) T cells, the latter with a high proliferative index (Ki67(+) ). B cells (CD20(+) ) and CD4(+) T cells were not detectable, and NK cells were rare. XY FISH showed that CD45(+) cells in PTCs were of recipient origin. Optimal treatment remains to be defined; two recovered without additional therapy, six were treated with anti-rejection regimens. Except for one patient, who later developed thrombotic microangiopathy and one with acute humoral rejection, all fully recovered within 2-4 weeks. Graft endothelium is the primary target of this process, attributable to as yet obscure mechanisms, arising during leukocyte recovery.

Thrombotic thrombocytopenic purpura associated with renal failure after autologous transplantation for multiple myeloma successfully treated with rituximab

Thrombotic thrombocytopenic purpura (TTP) is a haematological syndrome characterised by a dramatic onset requiring an urgent treatment with plasma exchange (PE). However, the prognosis is still dismal for PE related complications, a rate of failure and remarkable frequencies of relapse. TTP post transplantation is largely described as an outstanding, unusual complication of allogenic transplantation, but it is rarely mentioned after autologous transplantation. We describe a 62-year-old Caucasian patient who presented with TTP, accompanied by renal failure, after an autologous transplantation for multiple myeloma. PE together with hemodialysis was rapidly initiated but without any benefit. Since empirical administration of Rituximab, anti CD20 monoclonal antibody,was reported to be effective, we administered four courses of Rituximab inducing a complete remission of TTP and subsequently of the renal failure. This response to Rituximab in TTP post transplantation is suggestive of a possible implication of B-lymphocytes in the pathogenesis of TTP and it paves the way for an investigational approach in this settings.

Fatal pulmonary thromboembolism after a second course of high-dose chemotherapy with autologous peripheral blood stem cell transplantation

We describe a 4-yr-old boy with an occult primitive neuroectodermal tumor, who suffered fatal PTE after a second course of HDC with autologous PBSCT. On day + 52 after a second PBSCT, he was admitted because of respiratory distress. Respiratory failure rapidly progressed and he died within 4 days. The diagnosis of PTE was confirmed by a lung perfusion study with technetium-99m macroaggregated albumin, but too late to allow treatment. Although rare, PTE must be recognized as an important differential diagnosis when respiratory symptoms are observed after HDC with PBSCT.

Posttransplantation thrombotic thrombocytopenic purpura: a single-center experience and a contemporary review

OBJECTIVE

To assess the activity of von Willebrand factor-cleaving protease (vWF-CP) in patients with thrombotic thrombocytopenic purpura (TTP) complicating bone marrow transplantation (BMT) and peripheral blood stem cell transplantation (PBSCT).

PATIENTS AND METHODS

From March 1, 1999, to June 30, 2001, allogeneic and autologous hematopoietic stem cell transplantation was performed in 118 and 400 patients, respectively. We reviewed risk factors for development of posttransplantation TTP and measured vWF-CP activity during active TTP in 10 recipients.

RESULTS

The incidence of TTP after allogeneic and autologous transplantation was 6.8% (8/118) and 0.25% (1/400), respectively. Among the allogeneic transplant recipients, the incidence of TTP after nonmyeloablative (NMA) PBSCT, matched unrelated donor BMT, and sibling BMT or PBSCT was 15.4% (2/13), 11.8% (2/17), and 4.5% (4/88), respectively. Of the 10 patients with TTP, 9 (90%) had received extensive prior therapy, including autologous transplantation in both NMA recipients. Acute graft-vs-host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate in most affected patients. The vWF antigen level was elevated in all patients, and no patients showed evidence of vWF-CP deficiency. During active TTP, 6 patients had grade II-IV acute GVHD, 1 had extensive chronic GVHD, and 4 had cytomegalovirus viremia. Risk factor analysis for development of TTP showed that transplant type (NMA and matched unrelated donor) and source of stem cells (bone marrow vs peripheral blood stem cell) were significant.

CONCLUSIONS

Posttransplantation TTP was not found to be associated with severe vWF-CP deficiency. The elevated levels of vWF antigen are consistent with diffuse endothelial injury likely because of multiple interacting factors such as extensive prior therapy, GVHD, cyclosporine, and reactivation of cytomegalovirus. The disorder appears to be more frequent among patients with, or at risk for, acute GVHD, suggesting a possible role in the pathogenesis. Nonmyeloablative transplantation does not appear to confer a lesser risk, possibly for these reasons.

Thrombotic microangiopathy in blood and marrow transplant patients receiving tacrolimus or cyclosporine A

BACKGROUND

Cyclosporine A (CSA) and tacrolimus (FK-506) are both associated with thrombotic microangiopathy (TMA) in allogeneic BMT recipients, although it is not known which drug is more likely to cause the syndrome. The optimal treatment of BMT-associated TMA is also not known.

STUDY DESIGN AND METHODS

To estimate the risks, predisposing factors, and outcomes of TMA, data were analyzed from two cohorts of BMT patients who had received CSA or FK-506 in our institution with the same clinical definition for TMA. TMA was diagnosed in 11 of 55 patients (CSA, 3 of 24; FK-506, 8 of 31).

RESULTS

The daily risk of developing TMA was 0.12 percent for patients receiving CSA and 0.26 percent for those receiving FK-506 (p = 0.16, chi-square). Among patients receiving FK-506, sibling donor BMT recipients were as likely to develop TMA as matched unrelated donor recipients. Serum CSA and FK-506 concentrations were not elevated above the therapeutic range in most patients with TMA. The blood urea nitrogen to serum creatinine ratio was elevated in patients with TMA. Despite daily plasmapheresis, 9 of 11 patients died without resolution of TMA; however, the causes of death were multifactorial, including GVHD. Histologic evidence for TMA was absent in 1 patient who died with persistent clinical signs attributed to microangiopathy.

CONCLUSIONS

In this study, a high incidence of TMA was found in patients receiving either CSA or FK-506 following BMT, with uniform diagnostic criteria and strict monitoring. Neither drug showed elevated levels in most patients with TMA. Plasmapheresis was unsuccessful in reversing most cases of TMA.

Recent developments in toxic nephropathy

Toxic nephropathy is an important cause of reversible renal injury if detected early. Renal damage can be due to several different mechanisms affecting different segments of the nephron, renal microvasculature or interstitium. Clinical signs may not be apparent in the early stages and assessment of renal function should include thorough evaluation of glomerular filtration rate, proximal and distal tubular function. A kidney biopsy may be indicated to establish the cause and effect relationship. The presence of comorbid conditions such as older age, diabetes mellitus, hypertension and congestive heart failure have a significant influence on the patient's ability to recover from the toxic effects. A significant degree of drug-induced renal toxicity is only acceptable if the causative agent is used for the curative treatment of an underlying disease but not if the aim is the palliative or supportive therapy. The decision to reduce the dose or to stop the toxic agent must be based on the ultimate goal of therapy and the patient's baseline health status.