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

Time to evolve: predicting engineered T cell-associated toxicity with next-generation models

Despite promising clinical results in a small subset of malignancies, therapies based on engineered chimeric antigen receptor and T-cell receptor T cells are associated with serious adverse events, including cytokine release syndrome and neurotoxicity. These toxicities are sometimes so severe that they significantly hinder the implementation of this therapeutic strategy. For a long time, existing preclinical models failed to predict severe toxicities seen in human clinical trials after engineered T-cell infusion. However, in recent years, there has been a concerted effort to develop models, including humanized mouse models, which can better recapitulate toxicities observed in patients. The Accelerating Development and Improving Access to CAR and TCR-engineered T cell therapy (T2EVOLVE) consortium is a public–private partnership directed at accelerating the preclinical development and increasing access to engineered T-cell therapy for patients with cancer. A key ambition in T2EVOLVE is to design new models and tools with higher predictive value for clinical safety and efficacy, in order to improve and accelerate the selection of lead T-cell products for clinical translation. Herein, we review existing preclinical models that are used to test the safety of engineered T cells. We will also highlight limitations of these models and propose potential measures to improve them.

Chimeric antigen receptor T-cell therapy for the treatment of lymphoid malignancies: is there an excess risk for infection?

Therapy with genetically engineered chimeric antigen receptor (CAR) T cells targeting the CD19 antigen is promising for a number of refractory or relapsed B-cell malignancies. Information on the infectious complications of this immunotherapeutic strategy is scarce and difficult to interpret, as many factors influence infection incidence and outcomes. CAR T-cell therapy is usually given to patients with haematological cancers who have been heavily pretreated and are severely immunosuppressed. Moreover, the risk of infection is increased by the administration of lymphodepleting chemotherapy before CAR T-cell infusion, and by the development of complications such as cytokine release syndrome or immune effector cell-associated neurotoxicity syndrome, which are managed with anti-interleukin-6 antibodies, or corticosteroids, or both. On-target, off-tumour toxicities, such as B-cell aplasia, hypogammaglobulinaemia, and persistent or biphasic cytopenia, are common. In this Review, we evaluate the reported infectious complications of CAR T-cell therapy and associated risk factors and offer perspectives on its infection risk.

Fludarabine-based versus CHOP-like regimens with or without rituximab in patients with previously untreated indolent lymphoma: a retrospective analysis of safety and efficacy

Fludarabine-based regimens and CHOP (doxorubicin, cyclophosphamide, vincristine, prednisone)-like regimens with or without rituximab are the most common treatment modalities for indolent lymphoma. However, there is no clear evidence to date about which chemotherapy regimen should be the proper initial treatment of indolent lymphoma. More recently, the use of fludarabine has raised concerns due to its high number of toxicities, especially hematological toxicity and infectious complications. The present study aimed to retrospectively evaluate both the efficacy and the potential toxicities of the two main regimens (fludarabine-based and CHOP-like regimens) in patients with previously untreated indolent lymphoma. Among a total of 107 patients assessed, 54 patients received fludarabine-based regimens (FLU arm) and 53 received CHOP or CHOPE (doxorubicin, cyclophosphamide, vincristine, prednisone, or plus etoposide) regimens (CHOP arm). The results demonstrated that fludarabine-based regimens could induce significantly improved progression-free survival (PFS) compared with CHOP-like regimens. However, the FLU arm showed overall survival, complete response, and overall response rates similar to those of the CHOP arm. Grade 3–4 neutropenia occurred in 42.6% of the FLU arm and 7.5% of the CHOP arm (P < 0.000). Moreover, the FLU arm also had a higher occurrence of infection than the CHOP arm (27.8% vs 8.5%; P = 0.034). Multi-factor regression of infection revealed that only age (>60 years) and presentation of grade 3–4 myelosuppression were the independent factors to infection, and the FLU arm had significantly higher myelosuppression. In conclusion, the present study revealed that the use of fludarabine-based regimens could induce high rates of myelosuppression over CHOP-like regimens, in spite of significant increases in PFS.

Late-onset Pneumocystis jirovecii pneumonia post-fludarabine, cyclophosphamide and rituximab: implications for prophylaxis

Objective

Fludarabine, cyclophosphamide and rituximab (FCR) therapy for lymphoid malignancies has historically been associated with a low reported incidence of Pneumocystis jirovecii pneumonia (PJP). However, prophylaxis was routinely used in early studies, and molecular diagnostic tools were not employed. The objective of this study was to review the incidence of PJP during and post‐FCR in the era of highly sensitive molecular diagnostics and ¹⁸F‐fluorodeoxyglucose (FDG) positron emission tomography (PET)–computerised tomography (CT).

Methods

All patients treated with standard FCR at the Peter MacCallum Cancer Centre (March 2009 to June 2012) were identified from a medications management database. Laboratory‐confirmed PJP cases during this time were identified from an electronic database.

Results

Overall, 66 patients were treated with a median of 5.5 FCR cycles. Eight PJP cases were identified, 6 of whom had received chemotherapy prior to FCR. In 5 cases, ¹⁸F‐FDG PET demonstrated bilateral ground‐glass infiltrates. Median CD4⁺ lymphocyte counts at time of PJP diagnosis and 9–12 months following FCR were 123 and 400 cells/μL, respectively. In patients receiving no prophylaxis, 9.1% developed PJP during FCR. The rate following FCR was 18.4%, with median onset at 6 months (2.4–24 months).

Conclusion

Given the high rate of late‐onset PJP, consideration should be given for extended PJP prophylaxis for up to 12 months post‐FCR, particularly in pretreated patients. Further evaluation of the role of CD4⁺ monitoring is warranted to quantify risk of disease development and to guide duration of prophylaxis.

Management of patients with chronic lymphocytic leukemia treated with lenalidomide

Lenalidomide is an immunomodulatory drug that has shown preliminary activity in the treatment of chronic lymphocytic leukemia (CLL). Much is known about the safety profile of lenalidomide from experience in other hematologic malignancies, such as myelodysplastic syndromes and multiple myeloma. In addition to the known adverse effects associated with lenalidomide (e.g., myelosuppression, rash, fatigue), some unique effects (e.g., tumor flare reactions, tumor lysis syndrome) have arisen during clinical studies of CLL. Typical signs of tumor flare reactions include early onset of painful enlargement of the lymph nodes or spleen, with or without low-grade fever, rash, and bone pain. Management may require nonsteroidal anti-inflammatory drugs or a short course of corticosteroids. Dose delays or reductions usually are not required for tumor flare reactions. Signs of tumor lysis syndrome may include shortness of breath, peripheral edema, generalized weakness, sweating, fever, and tachycardia. Untreated tumor lysis syndrome can result in renal impairment and congestive heart failure. Careful monitoring and appropriate management of treatment-related side effects can help ensure that patients with CLL achieve maximum therapeutic benefit from lenalidomide therapy.

Chemoimmunotherapy of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) has long been regarded as an incurable disease of the elderly, worthy only of symptom palliation. Past generations of chemotherapy resulted in improved response rates, but did not change the natural history of the disease. Prolonged remissions and improvements in survival are, however, now possible owing to therapeutic advances including the use of purine analogs as frontline treatment and the emergence of monoclonal antibody-containing chemoimmunotherapy combinations. Moreover, consolidation strategies using non-cross resistant agents have improved the success rates of patients with residual disease at the end of induction treatment. Together, these new developments promise to deliver the tools necessary to render a state of minimal residual disease negativity in the majority of patients commencing treatment for CLL. This Review will outline the history and results of chemoimmunotherapy regimens that contain purine analogs and rituximab-the most successful combinations developed to date. We will also discuss how new developments in induction and consolidation strategies are leading the path towards cure.

Infectious complications in patients with acute myeloid leukemia treated according to the protocol with daunorubicin and cytarabine with or without addition of cladribine. A multicenter study by the Polish Adult Leukemia Group (PALG)

OBJECTIVES

The addition of cladribine to the standard regimen consisting of daunorubicin and cytarabine has been reported to increase the efficacy of induction therapy in acute myeloid leukemia (AML). The goal of this study was to determine the effect of this modification on the incidence and spectrum of infectious complications.

METHODS

Case report forms of 309 patients with newly diagnosed AML who had been enrolled in the prospective, randomized 'DAC-7 vs. DA-7' trial were reviewed. The frequency, etiology, localization, severity, and outcome of infections were compared for patients receiving only daunorubicin and cytarabine (DA-7) and those additionally treated with cladribine (DAC-7).

RESULTS

A total of 443 febrile episodes were reported with no significant difference between the treatment groups. A trend towards a higher frequency of bacteremias was observed among DA-7 patients compared to those in the DAC-7 group (31% vs. 21%; p=0.08). The treatment arms did not differ in terms of the distribution of the isolated Gram-positive, Gram-negative, fungal, and viral organisms. However, when bacteremias were considered, Gram-positive blood cultures tended to be more frequent in the DA-7 compared to the DAC-7 group (16% vs. 8.5%; p=0.07). This difference reached statistical significance when major blood bacteremias were analyzed separately (13% vs. 5%; p=0.02). Complete recovery from infections was observed in the majority of patients across both treatment arms and no significant difference was noted regarding infection-related mortality.

CONCLUSIONS

The addition of cladribine to standard induction chemotherapy has no impact on the incidence and spectrum of infectious complications in newly diagnosed AML patients.

Toxicity of fludarabine and cyclophosphamide with or without rituximab as initial therapy for patients with previously untreated mantle cell lymphoma: results of a randomised phase II study

The National Cancer Research Network (NCRN) is currently coordinating a Phase III randomised study (LY05) comparing fludarabine and cyclophosphamide (FC) with or without rituximab (R) for previously untreated mantle cell lymphoma (MCL). The combination of FC is well-recognised as significantly immunosuppressive and there are concerns that adding rituximab may increase infection risk further. The impact of rituximab on other markers of toxicity is also unclear. We analysed the toxicity data on 139 patients treated within the NCRN LY05 trial. Non-hematological toxicity was similar between the two treatment arms. The only difference in hematological toxicity was a higher rate of lymphocytopenia with fludarabine cyclophosphamide and rituximab (FCR), which did not translate into increased febrile episodes or infections. In conclusion, the addition of rituximab to FC for previously untreated MCL has no significant impact on toxicity.

The epidemiology and treatment of infections in cancer patients

Significant changes in the epidemiology of infectious complications in cancer patients have emerged during the past decade. Among blood culture isolates from febrile neutropenic patients, Gram-positive pathogens have become predominant, and an increasing spread of methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci must be taken into consideration. Risk factors such as indwelling venous catheters or chemotherapy-induced mucosal damage are associated with an increased incidence of Gram-positive infections. Invasive fungal infections, particularly invasive aspergillosis, have become most important in severely neutropenic patients and are associated with fatality rates of 40-60%. The use of nucleoside analogues and the CD52-antibody alemtuzumab induce a long-lasting lymphopenia facilitating the occurrence of opportunistic infections specifically caused by viruses and fungi. In elderly patients undergoing intensive myelosuppressive chemotherapy, infectious complications may be managed as successfully as in younger patients by appropriate antimicrobial therapy. The broad use of fluoroquinolones for antibacterial prophylaxis in neutropenic patients may lead to very high resistance rates among Gram-negative bacilli such as E. coli. In patients given moxifloxacin for infection prevention, unacceptably large numbers of Clostridium difficile-associated enterocolitis have been reported.

Fludarabine

Fludarabine (Fludara), a purine nucleoside analogue, has been extensively evaluated in the treatment of a number of lymphoproliferative malignancies, including various types of non-Hodgkin's lymphoma. Clinical studies have shown that fludarabine (alone, and particularly as a component of combination therapy) can result in high overall and complete response in adults with various types of non-Hodgkin's lymphoma, including follicular lymphoma. As mono- or combination therapy, intravenous fludarabine is as effective as several other standard treatment regimens in treatment-naive patients and is also effective in patients with recurrent or refractory disease. The efficacy of fludarabine therapy is improved with the use of rituximab, as part of the initial therapeutic regimen or as maintenance therapy, and deserves consideration. The once-daily oral formulation was effective in the treatment of patients with relapsed indolent B-cell non-Hodgkin's lymphoma; however, further studies are required to confirm its role and establish its efficacy relative to that of standard treatment in this patient population. Fludarabine has generally acceptable tolerability; however, it is associated with haematological adverse events, including myelosuppression. Fludarabine, therefore, provides a highly effective first- or second-line option in the treatment of non-Hodgkin's lymphoma.

Due to low infection rates no routine anti-infective prophylaxis is required in younger patients with chronic lymphocytic leukaemia during fludarabine-based first line therapy

The impact of the combination therapy fludarabine plus cyclophosphamide (FC) in comparison with fludarabine alone regarding the incidence and severity of infections among previously untreated patients with chronic lymphocytic leukaemia (CLL) was evaluated within a multicentre phase III study. A total of 375 patients, up to 65 years old, were randomised between fludarabine or FC for first line therapy. No routine anti-infective prophylaxis was provided. A total of 196 infectious episodes, including 33 severe infections, were documented. In the fludarabine arm, 32.9% of the patients developed an infectious complication compared with 39.9% in the FC arm (P = 0.2). No difference was observed in the rate of severe infections (Common Toxicity Criteria grades III and IV) between both treatment arms. Dose reductions were performed more frequently in FC-treated patients. Granulocyte colony-stimulating factor (G-CSF) was administered due to leucopenia in 5% of all patients. A multivariate regression model identified only elevated thymidine kinase, but not the treatment arm, as a statistically independent risk factor for infections. In summary, FC was not associated with a higher rate of infections compared with fludarabine alone. No routine antibiotic or virostatic prophylaxis, or preemptive treatment with G-CSF, is necessary in first line therapy with fludarabine-based regimens in younger patients with CLL, if adequate dose reduction is performed. The combination therapy FC is not associated with a higher rate of infections compared with fludarabine alone. No routine antibiotic or virostatic prophylaxis as well as preemptive treatment with G-CSF is necessary in first line therapy with fludarabine-based regimen in younger patients with CLL, if adequate dose reductions due to cytopenia or previous infections are performed.

The effect of immunoglobulin VH gene mutation status and other prognostic factors on the incidence of major infections in patients with chronic lymphocytic leukemia

BACKGROUND

Infections are a major factor in the clinical course of chronic lymphocytic leukemia (CLL) and account for 30% to 50% of all deaths. The pathogenesis of infections in CLL is related to hypo-gamma-globulinemia, T-cell immune dysfunction, and the immunosuppressive effect of treatment.

METHODS

The authors retrospectively assessed the correlations between new prognostic markers and types of infections encountered, the time taken to develop these infections, and infection-related mortality in 280 unselected patients with CLL.

RESULTS

One hundred patients (36%) had at least 1 major infection (median, 2 major infections; range, 1-8 major infections) over a median follow-up of 67 months. Infections were the most common cause of death, accounting for 51% of all fatalities. Older age (P = .007), clinical Stage B or C disease (P < .001), unmutated immunoglobulin (Ig)VH gene status (P < .001), genetic abnormalities (P < .001), positive CD38 status (P < .001), and type of initial therapy were associated with a significantly shorter time to first infection. Equally, patient age (P < .001), disease stage (P < .001), CD38 expression (P < .001), IgVH mutation status (P < .001), and genetic abnormalities (P = .003) had a significant impact on infection-related mortality.

CONCLUSIONS

Clinical stage at diagnosis, IgVH mutation status, and initial therapy were possible predictors of severe infections in patients with CLL. The current results may help to identify which patients with CLL are at particularly high risk of developing serious infections and, thus, should be considered for Ig or antibiotic prophylaxis.

Purine Analogues in Advanced T-Cell Lymphoid Malignancies

T-cell lymphomas account for 10% to 15% of all lymphoid malignancies. In advanced stages of T-cell lymphoma, single or multiagent chemotherapy and bioimmunotherapeutic agents have been used. Purine analogues have demonstrated activity in both refractory cutaneous T-cell lymphoma and peripheral T-cell lymphoma with response rates ranging from 20% to 70%. Response rates have been higher with pentostatin (60%) than with the other compounds in this class. The potential limitation to this therapy is the prolonged immunosuppression, which increases the risk of opportunistic injections in patients who are already at heightened risk for infections. Patients should be monitored closely with CD4 counts and surveillance for opportunistic infections. Future studies of purine analogues should evaluate patients who are less heavily pretreated and combination therapy with other agents such as alemtuzumab should be investigated in order to prolong the duration of disease remission.

Spectrum of infection, risk and recommendations for prophylaxis and screening among patients with lymphoproliferative disorders treated with alemtuzumab*

There is an increasing use of monoclonal antibodies in the treatment of haematological malignancies. Alemtuzumab (Campath-1H; Ilex Pharmaceuticals, San Antonio, TX, USA) is a monoclonal antibody reactive with the CD52 antigen used as first and second line therapy for two types of lymphoproliferative disorders: chronic lymphocytic leukaemia (CLL), and T-cell lymphomas [both peripheral (PTCL) and cutaneous (CTCL)]. With alemtuzumab therapy, viral, bacterial and fungal infectious complications are frequent, and may be life threatening. An understanding of the patients at highest risk and duration of risk are important in developing recommendations for empirical management, antimicrobial prophylaxis and targeted surveillance. This review discusses the infection risks associated with these lymphoproliferative disorders and their treatment, and provide detailed recommendations for screening and prophylaxis.

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.

Pediatric cancer patients in clinical trials of sepsis: factors that predispose to sepsis and stratify outcome

OBJECTIVE

To delineate the factors that predispose pediatric oncology and hematopoietic stem cell transplant (HSCT) patients to sepsis and to identify factors that stratify their outcome.

DATA SOURCE

Peer-reviewed literature available via MEDLINE search.

STUDY SELECTION

All types of study.

CONCLUSIONS

Pediatric oncology patients account for a relatively high proportion of severe sepsis in children. Available data suggest that outcomes among the non-HSCT oncology population are not substantially different from that of the general population. Data suggest that children with cancer (non-HSCT) who survive their septic episode will have a high probability of 6-month survival. In light of these findings, pediatric oncology patients are an important source of potential candidates for clinical trials of sepsis. In addition, HSCT patients seem to have significantly worse outcomes from sepsis than the non-HSCT oncology population, and thus, their participation in clinical trials is needed. However, in view of these worse outcomes, it is important to stratify the randomization for this population and to ensure that studies are adequately powered to assess outcomes in this subgroup.

Evidence-based guidelines for the management of neutropenia following outpatient hematopoietic stem cell transplantation

Hematopoietic stem cell transplantation (HSCT) involves the transfer of stem cells to establish hematopoiesis in patients who have received myeloablative chemotherapy with or without whole body irradiation. Following high-dose therapy and HSCT, all patients experience a period of neutropenia. Outpatient care delivery models place expanded responsibilities on patients and their families for the management of this treatment side effect. Proactive management of neutropenia is critical to decrease the depth and duration of neutropenia following HSCT, limit exposure to opportunistic and nosocomial pathogens, and ensure prompt intervention should febrile neutropenia or infection develop. Patient and family education, psychosocial support, and coordination of care are key nursing responsibilities.