The pharmacokinetics and pharmacodynamics of fludarabine phosphate in patients with renal impairment: a prospective dose adjustment study

Nephrons and non-relapse mortality: simplified comorbidity index and acute kidney injury are associated with NRM in adults undergoing allogeneic hematopoietic cell transplant

The Simplified Comorbidity Index (SCI) is a recently published 5-component, pre-transplant tool to predict non-relapse mortality (NRM) in allogeneic hematopoietic cell transplantation (alloHCT) patients. The SCI captures chronic kidney disease (CKD) using estimated glomerular filtration rate (eGFR) based on the CKD-EPI equation (KDIGO 2021 CKD-EPI), which may be more sensitive to predict risk of NRM than the creatinine cut-off in the 16-component, Hematopoietic Cell Transplant-Comorbidity Index (HCT-CI). We retrospectively assessed the ability of the SCI to risk-stratify patients and the impact of acute kidney injury (AKI) to NRM in adults who underwent alloHCT at the University of Minnesota. We included 373 patients who underwent their first alloHCT between 2015 and 2019. Through multivariate analysis, we found that patients with an SCI of greater than 4 had a higher risk of NRM. Additionally, we noted that AKIs stages 2-3 prior to day +100 was independently associated with a 3-fold greater NRM than patients who did not experience clinically significant AKI.

Transient acute kidney injury after chimeric antigen receptor T-cell therapy in patients with hematological malignancies

Background

Acute kidney injury (AKI) occurs in 30% of patients infused with chimeric antigen receptor (CAR) T-cells. The purpose of this study was to identify risk factors and long-term outcomes after AKI in patients who received CAR T-cell therapy.

Methods

Medical records of 115 adult patients with R/R hematological malignancies treated with CD19-targeted CAR T-cells at Vall d'Hebron University Hospital between July 2018 and May 2021. Baseline demographic data including age, gender, ethnicity, body mass index (BMI), and co-morbidities, as well as the type of hematological neoplasia and prior lines of therapy were collected. Laboratory parameters including serum creatinine and whole blood hemoglobin were retrospectively reviewed and values were gathered for days +1, +7, +14, +21, and +28 post-infusion.

Results

A total of 24/115 (21%) patients developed AKI related to CAR T-cell therapy; 6/24 with AKI over chronic kidney disease (CKD). Two patients had AKI in the context of lymphodepleting (LD) chemotherapy and the other 22 after CAR T-cell infusion, starting at day+1 in 3 patients, day+7 in 13 patients, day +14 in 1 patient, day+21 in 2 patients, and day+28 in 3 patients. Renal function was recovered in 19/24 (79%) patients within the first month after infusion. Male gender, CKD, cytokine release syndrome (CRS), and immune effector cell-associated neurotoxicity syndrome (ICANS) were associated with AKI. Male gender, CKD, ICANS grade ≥3 and CRS grade ≥2 were identified as independent risk factors for AKI on multivariable analysis. In terms of the most frequent CAR T-cell related complications, CRS was observed in 95 (82%) patients and ICANS in 33 (29%) patients. Steroids were required in 34 (30%) patients and tocilizumab in 37 (32%) patients. Six (5%) patients were admitted to the intensive care unit (1 for septic shock, 4 for CRS grade ≥2 associated to ICANS grade ≥2, and 1 for CRS grade ≥3). A total of 5 (4.4%) patients died in the first 30 days after CAR T-cell infusion for reasons other than disease progression, including 4 cases of infectious complications and 1 of heart failure.

Conclusion

Our results suggest that AKI is a frequent but mild adverse event, with fast recovery in most patients.

Has the shortage of fludarabine altered the current paradigm of lymphodepletion in favor of bendamustine?

The most common lymphodepletion regimen used prior to infusion of chimeric antigen receptor-T cells (CAR-T) is cyclophosphamide (CY) in combination with fludarabine (Flu) (CY-FLU). While cyclophosphamide (CY) possesses lymphotoxic effects, it concurrently preserves regulatory T cell activity, potentially affecting the efficacy of CAR-T cells. Moreover, the use of fludarabine (FLU) has been linked to neurotoxicity, which could complicate the early detection of immune effector cell-associated neurotoxicity syndrome (ICANS) observed in CAR-T cell therapy. Given the ongoing shortage of FLU, alternative lymphodepleting agents have become necessary. To date, only a limited number of studies have directly compared different lymphodepleting regimens, and most of these comparisons have been retrospective in nature. Herein, we review the current literature on lymphodepletion preceding CAR-T cell therapies for lymphoid hematologic malignancies, with a specific focus on the use of bendamustine (BEN). Recent evidence suggests that administering BEN before CAR-T cell infusion yields comparable efficacy, possibly with a more favorable toxicity profile when compared to CY-FLU. This warrants further investigation through randomized prospective studies.

Case Report: Lymphodepletion followed by CAR-T cell therapy with Idecabtagen vicleucel in a patient with severe renal impairment

Acute kidney injury and chronic kidney disease is common in multiple myeloma. Fludarabine which is part of lymphodepletion before CAR-T cell therapy is renally eliminated and its use is not recommended for patients with severe renal impairment defined as a glomerular filtration rate below 30ml/min/1.73m2. We administered fludarabine to a 58-year-old female patient with myeloma-associated severe renal impairment as part of lymphodepletion before Idecabtagen vicleucel infusion. Fludarabine was administered in reduced dose (15mg/m2) and cyclophosphamide with a dose of 300mg/m2 followed by hemodialysis over six hours using a larger filter (FX-100). The therapy was well tolerated with excellent CAR-T cell expansion and complete remission which is ongoing now beyond 12 months.

Management of multiple myeloma-related renal impairment: recommendations from the International Myeloma Working Group

Here, the International Myeloma Working Group (IMWG) updates its clinical practice recommendations for the management of multiple myeloma-related renal impairment on the basis of data published until Dec 31, 2022. All patients with multiple myeloma and renal impairment should have serum creatinine, estimated glomerular filtration rate, and free light chains (FLCs) measurements together with 24-h urine total protein, electrophoresis, and immunofixation. If non-selective proteinuria (mainly albuminuria) or involved serum FLCs value less than 500 mg/L is detected, then a renal biopsy is needed. The IMWG criteria for the definition of renal response should be used. Supportive care and high-dose dexamethasone are required for all patients with myeloma-induced renal impairment. Mechanical approaches do not increase overall survival. Bortezomib-based regimens are the cornerstone of the management of patients with multiple myeloma and renal impairment at diagnosis. New quadruplet and triplet combinations, including proteasome inhibitors, immunomodulatory drugs, and anti-CD38 monoclonal antibodies, improve renal and survival outcomes in both newly diagnosed patients and those with relapsed or refractory disease. Conjugated antibodies, chimeric antigen receptor T-cells, and T-cell engagers are well tolerated and effective in patients with moderate renal impairment.

Safety of CAR-T Cell Therapy in Patients With Renal Failure/Acute Kidney Injury: Focused Review

Chimeric antigen receptor (CAR) T-cell therapy is novel immunotherapy targeting specifically cancerous cells, and has been shown to induce durable remissions in some refractory hematological malignancies. However, CAR T-cell therapy has adverse effects, such as cytokine release syndrome (CRS), immune effector-associated neurotoxicity syndrome (ICANS), tumor lysis syndrome (TLS), and acute kidney injury (AKI), among others. Not many studies have covered the repercussions of CAR T-cell therapy on the kidneys. In this review, we summarized the available evidence on the safety profile of CAR T-cell therapy in patients with pre-existing renal insufficiency/AKI and in those who develop AKI as a result of CAR T-cell therapy. With a 30% incidence of AKI post-CAR T-cell, various pathophysiological mechanisms, such as CRS, hemophagocytic lymphohistiocytosis (HLH), TLS, serum cytokines, and inflammatory biomarkers, have been shown to play a role. However, CRS is commonly reported as an underlying mechanism. Overall, 18% of patients in our included studies developed AKI after receiving CAR T-cell therapy, and most cases were reversible with appropriate therapy. While phase-1 clinical trials exclude patients with significant renal toxicity, two studies (Mamlouk et al. and Hunter et al.) reported successful treatment of dialysis-dependent patients with refractory diffuse large B-cell lymphoma, and demonstrated that CAR T-cell therapy and lymphodepletion (Flu/Cy) can be safely administered.

Monoclonal Gammopathy of Undetermined Significance: A Comprehensive Review

Monoclonal Gammopathy of Undetermined Significance (MGUS) is an asymptomatic premalignant plasma cell dyscrasia with a predominate rise of the IgG immunoglobulin fraction without end-organ damage, often diagnosed incidentally. Despite its progression into various subsequent forms of hematological malignancies, MGUS remains underdiagnosed. A literature search was conducted using the Medline, Cochrane, Embase, and Google Scholar databases, including articles published until December 2022. Keywords used encompassed "Monoclonal Gammopathy of Undetermined Significance," "Plasma Cell dyscrasia," "Monoclonal gammopathy of renal significance," and "IgM Monoclonal gammopathy of Undetermined Significance," This study aimed to conduct a critical review to update knowledge regarding the pathophysiology, risk factors, clinical features, diagnostic protocols, complications, and current and novel treatments for MGUS. We recommend a multidisciplinary approach to manage MGUS due to the complexity of the illness's etiology, diagnosis, and therapy. This comprehensive review also highlights future prospects, such as developing screening protocols for at-risk populations, prevention of disease progression by early diagnosis through genome-wide association studies, and management using Daratumumab and NSAIDs.

Outcomes of CD19-Targeted Chimeric Antigen Receptor T Cell Therapy for Patients with Reduced Renal Function Including Dialysis

Patients with renal impairment (RI) are typically excluded from trials evaluating chimeric antigen receptor (CAR) T cell therapies. We evaluated the outcomes of patients with RI receiving standard of care (SOC) CAR T cell therapy for relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). In this retrospective, single-center cohort study of patients with R/R DLBCL treated with SOC axicabtagene ciloleucel (axi-cel) or tisagenlecleucel (tisa-cel) after 2 or more prior lines of therapy, renal and survival outcomes were compared based on RI and fludarabine dose reduction (DR) status. RI was defined by an estimated glomerular filtration rate <60 mL/min/1.73 m2 as determined by the Modification of Diet in Renal Disease equation using day -5 creatinine (Cr) values. Acute kidney injury (AKI) was identified and graded using standard Kidney Disease: Improving Global Outcomes criteria. Renal recovery was considered to occur if Cr was within .2 mg/mL of baseline by day +30. Fludarabine was considered DR if given at <90% of the recommended Food and Drug Administration label dose. Among 166 patients treated with CAR T cell therapy were 17 patients (10.2%) with baseline RI and 149 (89.8%) without RI. After CAR T cell infusion, the incidence of any grade AKI was not significantly different between patients with baseline RI and those without RI (42% versus 21%; P = .08). Similarly, severe grade 2/3 AKI was seen in 1 of 17 patients (5.8%) with baseline RI and in 11 of 149 patients (7.3%) without RI (P = 1). Decreased renal perfusion (28 of 39; 72%) was the most common cause of AKI, with cytokine release syndrome (CRS) contributing to 17 of 39 AKIs (44%). Progression-free survival (PFS) and overall survival (OS) did not differ between patients with RI and those without RI or between those who received standard-dose fludarabine and those who received reduced-dose fludarabine. In contrast, patients with AKI had worse clinical outcomes than those without AKI (multivariable PFS: hazard ratio [HR], 2.1; 95% confidence interval [CI], 1.2 to 3.7; OS: HR, 3.9; 95% CI, 2.1 to 7.4). Notably, peak inflammatory cytokine levels were higher in patients who experienced AKI. Finally, we describe 2 patients with end-stage renal disease (ESRD) on dialysis who received lymphodepletion and CAR T cell therapy. Baseline renal function did not affect renal or efficacy outcomes after CAR T cell therapy in DLBCL. On the other hand, patients with AKI went on to experience worse clinical outcomes. AKI was commonly related to CRS and high peak inflammatory cytokine levels. CAR T cell therapy is feasible in patients with ESRD and requires careful planning of lymphodepletion.

Chemotherapy for non-Hodgkin lymphoma in the hemodialysis patient: A comprehensive review

Chemotherapy for non-Hodgkin lymphoma (NHL) in the hemodialysis (HD) patient is a challenging situation. Because many drugs are predominantly eliminated by the kidneys, chemotherapy in the HD patient requires special considerations concerning dose adjustments to avoid overdose and toxicities. Conversely, some drugs are removed by HD and may expose the patient to undertreatment, therefore the timing of drug administration in relation to HD sessions must be carefully planned. Also, the metabolites of some drugs show different toxicities and dialysability as compared with the parent drug, therefore this must also be catered for. However, the pharmacokinetics of many chemotherapeutics and their metabolites in HD patients are unknown, and the fact that NHL patients are often treated with distinct multiagent chemotherapy regimens makes the situation more complicated. In a realm where uncertainty prevails, case reports and case series reporting on actual treatment and outcomes are extremely valuable and can aid physicians in decision making from drug selection to dosing. We carried out an exhaustive review of the literature and adopted 48 manuscripts consisting of 66 HD patients undergoing 71 chemotherapy regimens for NHL, summarized the data, and provide recommendations concerning dose adjustments and timing of administration for individual chemotherapeutics where possible. The chemotherapy regimens studied in this review include, but are not limited to, rituximab, cyclophosphamide + vincristine + prednisolone (CVP) and cyclophosphamide + doxorubicin + vincristine + prednisolone (CHOP)-like regimens, chlorambucil, ibrutinib, bendamustine, methotrexate, platinum compounds, cytarabine, gemcitabine, etoposide, ifosfamide, melphalan, busulfan, fludarabine, mogamulizumab, brentuximab vedotin, and 90 Y-ibritumomab tiuxetan.

The evaluation and management of monoclonal gammopathy of renal significance and monoclonal gammopathy of neurological significance

Despite the benign nature of monoclonal gammopathy of undetermined significance (MGUS), mounting data are associating MGUS with the development of organ dysfunction, specifically monoclonal gammopathy of renal significance (MGRS) and monoclonal gammopathy of neurological significance (MGNS), which could be associated with substantial morbidity. Emerging evidence suggests that patients with MGRS and MGNS could benefit from treatments used for myeloma, Waldenström macroglobulinemia, or chronic lymphocytic leukemia, depending on the underlying pathology. However, the treatment of MGRS and MGNS is not standardized, and potentially effective therapies might not be reimbursed because these conditions do not formally meet the criteria for malignant processes. The present review aims at establishing standards for the evaluation and management of MGRS and MGNS, which can facilitate the diagnosis of and provide therapeutic options for treating practitioners and patients affected by these conditions. The careful design and execution of clinical trials for patients with MGRS and MGNS are positively encouraged.

The interaction mechanism between fludarabine and human serum albumin researched by comprehensive spectroscopic methods and molecular docking technique

Fludarabine (Flu) is widely used to treat B-cell chronic lymphocytic leukemia. HSA is of the essence to human, especially in blood circulation system. The interaction mechanism between Flu and HSA was studied by comprehensive spectroscopic methods and molecular docking technique. UV-vis and FL spectrum results indicated that Flu bond with HSA, and there was a new complex produced at the binding site I in subdomain IIA. Association constants at 298 K were 1.637 × 10⁴ M^-1 and 1.552 × 10⁴ M^-1 at 310 K, respectively. The negative enthalpy (ΔH) and positive entropy (ΔS) values for the interaction revealed that the binding behavior was driven by hydrophobic forces and hydrogen bonds. The results obtained from UV, RLS spectra, 3D fluorescence and CD spectrum illustrated that Flu could change the secondary structure of HSA. According to molecule docking result, the binding energy of interaction is -11.15 kcal/mol.

Monoclonal gammopathy of renal significance: clinical manifestation, pathogenic characteristic and treatment

Monoclonal gammopathy of renal significance (MGRS) is a group of renal disorders caused by a monoclonal immunoglobulin (MIg) secreted by a dangerous plasmatic/B-cell clone hyperplasia through MIg deposition or dysfunction of complement pathway, with increasing risk of progress to end stage renal disease (ESRD) and the underlying hematologic malignancy. The combination of renal biopsy, complete laboratory examination and bone marrow biopsy is an indispensable diagnostic tool for MGRS to identify accurately and unequivocally the pathogenic monoclonal MIg and provide guidance to treatment. Treatment of MGRS is composed of conventional therapy, chemotherapy, and stem cell transplantation to target the underlying clone and eliminate the noxious MIg on the basis of clinical data of some retrospective studies and a small amount of prospective trial. In addition, it is worthwhile point out assessment of therapeutic effect is significantly relevant for renal and overall prognosis. Thus, by comprehensively analyzing the clinical manifestations and pathogenic characteristic of MGRS, early recognition and prompt treatment can improve the prognosis and prevent post-translation recurrence with multidisciplinary cooperation.

Pharmacokinetics and Model-Based Dosing to Optimize Fludarabine Therapy in Pediatric Hematopoietic Cell Transplant Recipients

A prospective multicenter study was conducted to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of fludarabine plasma (f-ara-a) and intracellular triphosphate (f-ara-ATP) in children undergoing hematopoietic cell transplantation (HCT) and receiving fludarabine with conditioning. Plasma and peripheral blood mononuclear cells (PBMCs) were collected over the course of therapy for quantitation of f-ara-a and f-ara-ATP. Nonlinear mixed-effects modeling was used to develop the PK model, including identification of covariates impacting drug disposition. Data from a total of 133 children (median age, 5 years; range, .2 to 17.9) undergoing HCT for a variety of malignant and nonmalignant disorders were available for PK-PD modeling. The implementation of allometric scaling of PK parameters alone was insufficient to describe drug clearance, particularly in very young children. Renal impairment was predicted to increase drug exposure across all ages. The rate of f-ara-a entry into PBMCs (expressed in pmoles per million cells) decreased over the course of therapy, resulting in 78% lower f-ara-ATP after the fourth dose (1.7 pmoles/million cells [range, .2 to 7.2]) compared with first dose (7.9 pmoles/million cells [range, .7 to 18.2]). The overall incidence of treatment-related mortality (TRM) was low at 3% and 8% at days 60 and 360, respectively, and no association with f-ara-a exposure and TRM was found. In the setting of malignancy, disease-free survival was highest at 1 year after HCT in subjects achieving a systemic f-ara-a cumulative area under the curve (cAUC) greater than 15 mg*hour/L compared to patients with a cAUC less than 15 mg*hour/L (82.6% versus 52.8% P = .04). These results suggest that individualized model-based dosing of fludarabine in infants and young children may reduce morbidity and mortality through improved rates of disease-free survival and limiting drug-related toxicity. ClinicalTrials.gov Identifier: NCT01316549.

Personalized fludarabine dosing to reduce nonrelapse mortality in hematopoietic stem-cell transplant recipients receiving reduced intensity conditioning

Patients undergoing hematopoietic cell transplantation (HCT) with reduced intensity conditioning (RIC) commonly receive fludarabine. Higher exposure of F-ara-A, the active component of fludarabine, has been associated with a greater risk of nonrelapse mortality (NRM). We sought to develop a model for fludarabine dosing in adult HCT recipients that would allow for precise dose targeting and predict adverse clinical outcomes. We developed a pharmacokinetic model from 87 adults undergoing allogeneic RIC HCT that predicts F-ara-A population clearance (Clpop) accounting for ideal body weight and renal function. We then applied the developed model to an independent cohort of 240 patients to identify whether model predictions were associated with NRM and acute graft versus host disease (GVHD). Renal mechanisms accounted for 35.6% of total F-ara-A Clpop. In the independent cohort, the hazard ratio of NRM at day 100 was significantly higher in patients with predicted F-ara-A clearance (Clpred) <8.50 L/h (P < 0.01) and area under the curve (AUCpred) >6.00 μg × h/mL (P = 0.01). A lower Clpred was also associated with more NRM at month 6 (P = 0.01) and trended toward significance at 12 months (P = 0.05). In multivariate analysis, low fludarabine clearance trended toward higher risk of acute GVHD (P = 0.05). We developed a model that predicts an individual's systemic F-ara-A exposure accounting for kidney function and weight. This model may provide guidance in dosing especially in overweight individuals and those with altered kidney function.

Pharmacotherapeutic Management of Chronic Lymphocytic Leukaemia in Patients with Comorbidities: New Agents, New Hope

Chronic lymphocytic leukaemia (CLL) is mostly considered a disease of the elderly. As such, many patients present with comorbidities. Several scores allow for a qualitative and quantitative assessment of comorbidity in patients with CLL. Although our knowledge about the impact of comorbidity on outcomes in patients with CLL is still incomplete, it is becoming increasingly apparent that comorbidities could negatively interfere with CLL treatment. Recently, a number of new agents have been approved for use in patients with previously untreated CLL and comorbidities (i.e. obinutuzumab, ofatumumab), as well as in patients with previously treated or high-risk CLL (i.e. idelalisib, ibrutinib). This review discusses the role of comorbidity in patients with CLL, together with the changing treatment landscape for CLL in this patient population.

Combined Bone Marrow and Kidney Transplantation for the Induction of Specific Tolerance

The induction of specific tolerance, in order to avoid the detrimental effects of lifelong systemic immunosuppressive therapy after organ transplantation, has been considered the "Holy Grail" of transplantation. Experimentally, tolerance has been achieved through clonal deletion, through costimulatory blockade, through the induction or infusion of regulatory T-cells, and through the establishment of hematopoietic chimerism following donor bone marrow transplantation. The focus of this review is how tolerance has been achieved following combined bone marrow and kidney transplantation. Preclinical models of combined bone marrow and kidney transplantation have shown that tolerance can be achieved through either transient or sustained hematopoietic chimerism. Combined transplants for patients with multiple myeloma have shown that organ tolerance and prolonged disease remissions can be accomplished with such an approach. Similarly, multiple clinical strategies for achieving tolerance in patients without an underlying malignancy have been described, in the context of either transient or durable mixed chimerism or sustained full donor hematopoiesis. To expand the chimerism approach to deceased donor transplants, a delayed tolerance approach, which will involve organ transplantation with conventional immunosuppression followed months later by bone marrow transplantation, has been successful in a primate model. As combined bone marrow and organ transplantation become safer and increasingly successful, the achievement of specific tolerance may become more widely applicable.

Preparative regimen dosing for hematopoietic stem cell transplantation in patients with chronic kidney disease: analysis of the literature and recommendations

Hematopoietic stem cell transplantation (HSCT) is a potentially life-saving therapy that has traditionally been associated with high treatment-related mortality due to direct regimen toxicity and a high incidence of graft-versus-host disease. Historically, pre-existing renal insufficiency has been considered an exclusion criterion for transplantation. The advent of nonmyeloablative conditioning regimens as a less toxic modality for treatment has made HSCT more accessible to elderly patients and patients with comorbidities, such as renal impairment. However, there is no clear standard for how to dose preparative regimens for patients with chronic renal impairment who undergo HSCT. This article serves as a review of the current literature to provide dosing recommendations for commonly used preparative agents in the setting of chronic kidney disease, with the aim of providing optimal dosing for this patient population.

Ocular toxicity of fludarabine: a purine analog

The purine analogs, fludarabine and cladribine represent an important class of chemotherapy agents used to treat a broad spectrum of lymphoid malignancies. Their toxicity profiles include dose-limiting myelosuppression, immunosuppression, opportunistic infection and severe neurotoxicity. This review summarizes the neurotoxicity of high- and standard-dose fludarabine, focusing on the clinical and pathological manifestations in the eye. The mechanisms of ocular toxicity are probably multifactorial. With increasing clinical use, an awareness of the neurological and ocular vulnerability, particularly to fludarabine, is important owing to the potential for life- and sight-threatening consequences.

How I treat monoclonal gammopathy of renal significance (MGRS)

Recently, the term monoclonal gammopathy of renal significance (MGRS) was introduced to distinguish monoclonal gammopathies that result in the development of kidney disease from those that are benign. By definition, patients with MGRS have B-cell clones that do not meet the definition of multiple myeloma or lymphoma. Nevertheless, these clones produce monoclonal proteins that are capable of injuring the kidney resulting in permanent damage. Except for immunoglobulin light chain amyloidosis with heart involvement in which death can be rapid, treatment of MGRS is often indicated more to preserve kidney function and prevent recurrence after kidney transplantation rather than the prolongation of life. Clinical trials are rare for MGRS-related kidney diseases, except in immunoglobulin light chain amyloidosis. Treatment recommendations are therefore based on the clinical data obtained from treatment of the clonal disorder in its malignant state. The establishment of these treatment recommendations is important until data can be obtained by clinical trials of MGRS-related kidney diseases.

Impact of dose intensity on outcome of fludarabine, cyclophosphamide, and rituximab regimen given in the first-line therapy for chronic lymphocytic leukemia

Fludarabine-cyclophosphamide-rituximab is the most efficient first-line treatment for chronic lymphocytic leukemia patients. Many dose adjustments of the original MD Anderson Cancer Center regimen have been proposed. However, whether fludarabine-cyclophosphamide-rituximab relative dose intensity may have an impact on outcome has not yet been investigated. We retrospectively assessed relative dose intensity in 106 community-based patients included in our regional healthcare network from 2004-11, all receiving fludarabine-cyclophosphamide-rituximab as first-line treatment outside clinical trials. Dose reductions were observed in 51.4% of patients, mainly decided by the individual physician and not based on recommendations (52.7%), while there were fewer reports of toxicity or dose reduction because of impaired renal function. Progression-free survival was significantly reduced in patients who had a reduction in dose intensity of more than 20% in fludarabine-cyclophosphamide and/or rituximab. Multivariate analysis showed dose of rituximab had a significant impact on minimal residual disease and progression-free survival. Although prophylactic granulocyte-colony stimulating factor significantly reduced the rate of grade 3-4 neutropenia and febrile neutropenia, it had no impact on relative dose intensity and outcome. This study shows that, in routine clinical practice, there is low adherence to the original MD Anderson Cancer Center fludarabine-cyclophosphamide-rituximab schedule, and that the decision to modify dosage was mostly taken by the individual physician and was based on anticipated toxicity. This study shows that reduction of fludarabine-cyclophosphamide and, more importantly, of rituximab doses seriously interferes with progression-free survival.

Treatment and management of chronic lymphocytic leukemia in the elderly: what the pharmacist clinician should know

OBJECTIVE

To review the literature for current treatment options and supportive care management for elderly patients with chronic lymphocytic leukemia (CLL).

DATA SOURCES

PubMed searches using the terms chronic lymphocytic leukemia, elderly, practice guidelines, and controlled clinical trials were performed from 1949 through August 2011. Reference lists from relevant articles were examined for additional studies, review articles, and guidelines.

STUDY SELECTION AND DATA EXTRACTION

Eighty-three articles were generated and abstracted articles were chosen based on trial results that changed clinical practice, resulted in approval of new drugs for CLL by the Food and Drug Administration and/or had clinical relevance to the elderly population.

DATA SYNTHESIS

Fit elderly CLL patients have more treatment options than frail elderly. Most studies include patients younger than 65 years of age, and recent advances in treatment may not prove beneficial for all ages. Clinicians should use available evidence and clinical judgment when treating and monitoring elderly CLL patients.

CONCLUSION

Treatment armamentarium has improved over the last decade, yet clinical trials research should include more elderly cohorts as new agents are developed. Increased awareness of supportive care issues improves quality of life for a population with multiple disease complications.

Management of hematological malignancies in patients affected by renal failure

The management of hematological malignancies (HM) in renally impaired patients may be a difficult task. Indeed, the kidney represents a major elimination pathway for many chemotherapeutic agents and their metabolites, whose serum levels are not usually measured in daily clinical practice. In addition, many antineoplastic drugs have a narrow therapeutic index for which they require dose adjustment when administered to patients with renal failure. Only limited data regarding the use of chemotherapy in patients with renal impairment and in those on dialysis are available. Indeed, renal patients with HM are often excluded from most clinical trials. Thus far, in order to provide recommendations, we have reviewed the pertinent literature, gathering information from published guidelines regarding chemotherapy in patients with kidney dysfunction and from articles describing the use of individual agents in renal patients with HM.

High fludarabine exposure and relationship with treatment-related mortality after nonmyeloablative hematopoietic cell transplantation

Despite its common use in nonmyeloablative preparative regimens, the pharmacokinetics of fludarabine are poorly characterized in hematopoietic cell transplantation (HCT) recipients and exposure-response relationships remain undefined. Our objective of this study was to evaluate the association between plasma F-ara-A exposure, the systemically circulating moiety of fludarabine, and engraftment, acute graft vs host disease (GVHD), treatment-related mortality (TRM) and survival after HCT. The preparative regimen consisted of cyclophosphamide 50 mg/kg/day i.v. day −6; plus fludarabine 30-40 mg/m²/day i.v. on days −6 to −2 and TBI 200 cGy on day −1. F-ara-A pharmacokinetics were performed with the first dose of fludarabine in 87 adult patients. Median (range) F-ara-A AUC _(0-∞) was 5.0 ug*hr/mL (2.0-11.0), clearance 15.3 L/hour (6.2-36.6), C_min 55 ng/mL (17-166), and concentration on day_zero 16.0 ng/mL (0.1-144.1). Despite dose reductions, patients with renal insufficiency had higher F-ara-A exposures. There was strong association between high plasma concentrations of F-ara-A and increased risk of TRM and reduced overall survival. Patients with an AUC_(0-∞) greater than 6.5 ug*hr/mL had 4.56 greater risk of TRM and significantly lower survival. These data suggest that clinical strategies are needed to optimize dosing of fludarabine to prevent overexposure and toxicity in HCT.

Development of fludarabine formulations in the treatment of chronic lymphocytic leukemia

Fludarabine is an antineoplastic agent used in the treatment of hematological malignancies, particularly chronic lymphocytic leukemia (CLL) and indolent B-cell lymphoma. Because of its immunosuppressive effects, fludarabine has been added to reduced intensity conditioning regimens. The oral formulation of fludarabine has become widely available. Pharmacokinetic studies have shown that an oral dose of 40 mg/m²/d would provide systemic drug exposure similar to the standard intravenous (IV) dose of 25 mg/m²/d. The oral dose can be taken once daily without any dietary restrictions. Dose adjustments are mandatory in patients with renal impairment to avoid increased toxicity. Several noncomparative trials in previously untreated and treated patients with CLL have shown that treatment with the oral formulation demonstrates similar efficacy compared to historical control groups treated with the IV formulation. The tolerability profile of oral fludarabine seems similar to that of the IV formulation. Myelosuppression and infectious complications are the most frequently reported adverse events. Gastrointestinal toxicity is more frequent with the oral formulation, but is usually of mild or moderate severity. Although oral fludarabine makes treatment more convenient, health care workers must be aware of the compliance behavior of each patient.

Anticancer drug therapy in the older cancer patient: pharmacology and polypharmacy

OPINION STATEMENT

Older patients currently are the largest group of oncology patients and their numbers will continue to expand. There has been minimal participation of older patients in clinical trials. This has resulted in a lack of data to make high-level evidence-based decisions with regard to chemotherapy. There has now been a number of clinical trials which have given information with regard to age-related changes and the spectrum of toxicity that occurs with older patients. There is also an expanding literature on organ dysfunction. The overall data seem to indicate that there are a very few age-related changes in the pharmacokinetics of chemotherapy. The small changes that are present have not been clinically significant. It seems that the pattern of toxicity is more reflective of patient selection (functional status, performance status), comorbidity, and drug scheduling. The large number of drugs with significant renal excretion requires careful evaluation of renal function. Future clinical trial design needs to be adapted to older patients. Therefore, drugs, which will be primarily used by older patients, should be studied in older patients. These studies should involve pharmacokinetics, and oral therapies should include measurements of compliance. Phase II trials of new agents should consider prospectively dividing groups of patients by age (i.e., <75 years vs. >or=75 years). Phase I trials should consider accruing older patients. The studies can be performed in the older group by using progressive degrees of functional impairment and increasing comorbidity as a surrogate for dose limiting toxicity. Functional independence as a clinical benefit of cancer treatment in older individuals should be considered as an endpoint. Overall survival may not be an appropriate endpoint in clinical trials in the oldest group. Clinical trials should consider studying long-term functional and medical consequences of cancer treatment in long-term older cancer survivors. Journal editors should encourage the inclusion of age-related analyses in the reporting of clinical trials to provide meaningful information for clinicians caring for older patients. Ideally, the clinical trial design should prospectively incorporate age analysis to maximize clinical benefit of data generated. A careful assessment of medication used in older patients needs to be part of routine evaluation to minimize the adverse effects of polypharmacy.

Fludarabine-based nonmyeloablative stem cell transplantation for sickle cell disease with and without renal failure: clinical outcome and pharmacokinetics

End-organ damage is common in patients with sickle cell disease (SCD) thereby limiting the use of allogeneic stem cell transplantation (SCT). We report the outcome of 2 adult SCD patients, 1 with end-stage renal disease (ESRD), who underwent fludarabine-based nonmyeloablative SCT from HLA-identical matched siblings. To prevent fludarabine toxicity, the patient with ESRD underwent aggressive dialysis following adjusted fludarabine dosing. Pharmacokinetics of the fludarabine metabolite F-Ara-A was studied on the patient with ESRD and 2 additional patients with normal renal function. Both patients with SCD achieved full donor erythroid chimerism, have normal blood counts, and are on no immunosuppressive medications. With a 20% dose reduction followed by daily dialysis, we achieved fludarabine drug exposure that is nearly identical to that achieved in patients with normal renal function. We conclude that fludarabine-based nonmyeloablative allogeneic SCT for adult patients with SCD is feasible, even in the setting of ESRD.

International Society of Geriatric Oncology Chemotherapy Taskforce: evaluation of chemotherapy in older patients--an analysis of the medical literature

The elderly comprise the majority of patients with cancer and are the recipients of the greatest amount of chemotherapy. Unfortunately, there is a lack of data to make evidence-based decisions with regard to chemotherapy. This is due to the minimal participation of older patients in clinical trials and that trials have not systematically evaluated chemotherapy. This article reviews the available information with regard to chemotherapy and aging provided by a task force of the International Society of Geriatric Oncology (SIOG). Due to the lack of prospective data, the conclusions and recommendations made are a consensus of the participants. Extrapolation of data from younger to older patients is necessary, particularly to those patients older than 80 years, for which data is almost entirely lacking. The classes of drugs reviewed include alkylators, antimetabolites, anthracyclines, taxanes, camptothecins, and epipodophyllotoxins. Clinical trials need to incorporate an analysis of chemotherapy in terms of the pharmacokinetic and pharmacodynamic effects of aging. In addition, data already accumulated need to be reanalyzed by age to aid in the management of the older cancer patient.

International Society of Geriatric Oncology (SIOG) recommendations for the adjustment of dosing in elderly cancer patients with renal insufficiency

A SIOG taskforce was formed to discuss best clinical practice for elderly cancer patients with renal insufficiency. This manuscript outlines recommended dosing adjustments for cancer drugs in this population according to renal function. Dosing adjustments have been made for drugs in current use which have recommendations in renal insufficiency and the elderly, focusing on drugs which are renally eliminated or are known to be nephrotoxic. Recommendations are based on pharmacokinetic and/or pharmacodynamic data where available. The taskforce recommend that before initiating therapy, some form of geriatric assessment should be conducted that includes evaluation of comorbidities and polypharmacy, hydration status and renal function (using available formulae). Within each drug class, it is sensible to use agents which are less likely to be influenced by renal clearance. Pharmacokinetic and pharmacodynamic data of anticancer agents in the elderly are needed in order to maximise efficacy whilst avoiding unacceptable toxicity.

Fludarabine in chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in the Western world. Historically, CLL patients have received prednisone- or chlorambucil-containing regimens, resulting in modest responses and a slim chance of long-term survival. The addition of purine nucleoside analogues, specifically fludarabine, to the armamentarium has significantly improved efficacy in treatment-naive or heavily pretreated CLL patients. Since the 1980s, fludarabine monotherapy has demonstrated an improvement in response over historical chemotherapeutic agents. Single-agent fludarabine therapy has expanded into a combination regimen containing cyclophosphamide and has further evolved to incorporate monoclonal antibodies. A review of the fludarabine literature shows that these advancements in fludarabine-containing therapy have enhanced the overall patient response with a potential increase in survival time, thus representing progress towards a superior treatment for CLL.

The influence of increasing age on the deliverability and toxicity of fludarabine-based combination chemotherapy regimens in patients with indolent lymphoproliferative disorders

BACKGROUND

Fludarabine-based combination chemotherapy regimens are highly effective in the treatment of patients with indolent lymphoproliferative disorders. Despite the prevalence of such disorders in older patients, the effect of increasing age on the deliverability of these regimes has not been assessed.

METHODS

The authors analyzed the effect of increasing age on the deliverability and toxicity of 3 fludarabine-based regimens, all using fludarabine 25 mg/m2 per day for 3 days intravenously every 28 days, in 180 patients who were stratified into 2 age groups (age <60 years and age > or =60 years), with multivariate analysis to control for other differences between groups. The authors also explored the impact of age > or =70 years within the older cohort.

RESULTS

Older patients were more likely to experience an episode of nonsevere hematologic or infectious toxicity, but there was no difference in the rate of severe toxicity. Toxicity rates per cycle did not differ between age groups. The rates of neutropenia (absolute neutrophil count [ANC], < 1.0 x 10(9)/L) and severe neutropenia (ANC, 0.5 x 10(9)/L) were 22% and 13%, respectively, in older patients versus 20% and 11%, respectively, in younger patients (P > .1 for both). The rates of thrombocytopenia (platelet count, <100 x 10(9)/L) and severe thrombocytopenia (platelet count, <50 x 10(9)/L) were 21% and 5%, respectively, in older patients and 16% and 5%, respectively, in younger patients (each P value > .1). The rate of infection was 18% per cycle in older patients and 15% per cycle in younger patients (P = .2), with no difference noted in severity. Other organ toxicities were uncommon and showed no difference between age groups. The treatment-related mortality rate was <1% in both cohorts (P > .5). In multivariate analysis, increasing age and performance status influenced the incidence of hematologic toxicity, whereas only performance status influenced the rate of infection and severe infection.

CONCLUSIONS

Fludarabine-based combination chemotherapy regimens were well tolerated and can be delivered safely to older patients who have a good performance status with modestly increased myelosuppression but no increase in severe infectious complications or treatment-related mortality.

Dialysate concentration and pharmacokinetics of 2F-Ara-A in a patient with acute renal failure

Fludarabine is frequently used for treatment of B-cell chronic lymphocytic leukemia and in conditioning regimes for hematopoietic cell transplantations. The total body clearance of the principal metabolite 2-fluoro-ara-A (2F-Ara-A) correlates with the creatinine clearance. We report data on total dialysate concentration as well as pharmacokinetics of 2F-Ara-A in a patient with anuric acute renal failure. On three consecutive days the patient received a daily dose of 80 mg (40 mg/m(2)) fludarabine and underwent three consecutive extended (daily) dialysis (ED) sessions. ED removed a considerable amount of the drug. The average dialysis clearance was 33.85 ml/min which is about 25% of the clearance in patients without renal failure. No toxic side effects of the treatment were observed. This case suggests that fludarabine treatment can be considered in patients requiring dialysis if dose reduction and adequate removal of the drug by hemodialysis is provided.

Drug dosing in chronic kidney disease

Patients with chronic kidney disease (CKD) are at high risk for adverse drug reactions and drug-drug interactions. Drug dosing in these patients often proves to be a difficult task. Renal dysfunction-induced changes in human pathophysiology regularly results may alter medication pharmacodynamics and handling. Several pharmacokinetic parameters are adversely affected by CKD, secondary to a reduced oral absorption and glomerular filtration; altered tubular secretion; and reabsorption and changes in intestinal, hepatic, and renal metabolism. In general, drug dosing can be accomplished by multiple methods; however, the most common recommendations are often to reduce the dose or expand the dosing interval, or use both methods simultaneously. Some medications need to be avoided all together in CKD either because of lack of efficacy or increased risk of toxicity. Nevertheless, specific recommendations are available for dosing of certain medications and are an important resource, because most are based on clinical or pharmacokinetic trials.

A new model for predicting infectious complications during fludarabine-based combination chemotherapy among patients with indolent lymphoid malignancies

BACKGROUND

Fludarabine-containing combination chemotherapy regimens are increasingly used in the treatment of indolent lymphoid malignancies, with the associated risk of infection being the major toxicity. Predictors of infection during fludarabine-containing combination therapy are poorly defined and optimal strategies for infection prophylaxis are not known. The authors analyzed their experience with patients treated with the fludarabine-mitoxantrone (FM) or fludarabine-cyclophosphamide (FC) regimens to develop a predictive model for infections.

METHODS

Ninety-two patients with indolent lymphoid malignancies were treated with FM (n = 29) or FC (n = 63). Baseline variables including age, gender, regimen, disease histology, previous therapy, time from diagnosis to current treatment, performance status, renal function, absolute neutrophil count (ANC), lymphocyte count, and immunoglobulin G levels were examined retrospectively for their association with risk of infectious complications during or within 4 weeks of therapy.

RESULTS

Six risk factors were associated with infectious complications: age > 60 years, > or = 3 previous therapies, previous fludarabine exposure, time from diagnosis to current treatment of > 3 years, performance status > or = 2, and baseline ANC < 2.0 x 10(9)/L. Compared with patients with 0-2 risk factors, patients with > or = 3 risk factors had higher infection rates (26% vs. 7% per cycle, P < 0.0001), more Grade 4 neutropenia (41% vs. 8% per cycle, P < 0.0001), and more neutropenic sepsis (15% vs. 1% per cycle, P < 0.0001).

CONCLUSIONS

Infection risk during fludarabine-containing combination chemotherapy was predicted with a model comprising six baseline risk factors. Patients predicted to be at high risk of infection were an appropriate group for consideration of prophylactic strategies.

Pharmacological factors influencing anticancer drug selection in the elderly

Persons over the age of 65 years are the fastest growing segment of the US population. In the next 30 years this segment will represent more than 20% of the population. Fifty percent of all cancers occur in this age group and therefore the total cancer burden is expected to rise. Data are becoming available that will better guide the use of chemotherapy in the older patient population. Studies are presented discussing pharmacokinetic data on a number of chemotherapeutic agents with an emphasis on those that have entered clinical practice over the past few years. Many of these agents seem to have a beneficial therapeutic index, particularly in regard to older patients. Aging can affect the pharmacokinetics of chemotherapy in a number of ways. Absorption is only modified minimally by age. The greater concern with the use of oral drugs is patient compliance. Volume of distribution is affected by changes in body composition, anaemia and decreased plasma albumin concentration. There are many drugs in which renal excretion plays an important role. Decline in glomerular filtration is a consistent phenomenon with aging. Drug metabolism is primarily affected by changes in the P450 system and coadministration of drugs which also interact with this important enzyme system. The selection of chemotherapy in the elderly is frequently determined by degree of comorbidity and the patients' functional status. These factors are critical and can often determine response and toxicity. This article discusses the changes that occur with antimetabolites, camptothecins, anthracyclines, taxanes, platinum compounds, epipodophyllotoxins and vinca alkaloids. There has also been an increasing trend toward the use of oral chemotherapy. Factors that must be considered in selecting chemotherapeutic agents include limitations of saturability of absorption, patient compliance and the pharmacokinetic and pharmacodynamic changes that occur in older patients. Interpatient variability and age-related changes in drug metabolism are discussed. Careful attention to the physiological changes with age and dose adjustments necessary for end-organ dysfunction (renal, hepatic) are needed to ensure the safe administration of chemotherapy. In this article specific diseases are discussed (breast, colon, ovarian and non-small lung cancers) with recommendations for drug selection in adjuvant chemotherapy and the treatment of metastatic disease. Future studies will need to incorporate these various factors to properly evaluate chemotherapy in older patients. Research and educational initiatives targeted to this population will need to be a priority.

Advances in the therapy of chronic lymphocytic leukemia

Chronic lymphocytic leukemia therapy has changed dramatically over the past decade, with recent studies supporting the use of fludarabine as the initial therapy for symptomatic disease. New findings relative to the use of fludarabine and complications arising from this therapy are reviewed. Exciting combination approaches using monoclonal antibodies such as rituximab or Campath-1H in combination with fludarabine offer the opportunity to improve the complete response rate further in chronic lymphocytic leukemia. Furthermore, the field of experimental therapeutics for chronic lymphocytic leukemia was advanced by the description of a new mouse model of human chronic lymphocytic leukemia and identification of several disrupted signal transduction pathways in this disease. The description of therapies that target AKT, protein kinase C, phosphodiesterase 4, mammalian target of rapamycin, histone deacetylase, and methyltransferase offer the opportunity to utilize molecularly targeted therapy for this disease. Such targeted approaches offer hope that we might be on the threshold to changing the natural history of chronic lymphocytic leukemia.