Fludarabine in resistant or relapsing B-cell chronic lymphocytic leukemia: the Spanish Group experience

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.

Treatment of relapsed or refractory chronic lymphocytic leukemia

BACKGROUND

Recent advances in the treatment of chronic lymphocytic leukemia (CLL) have moved beyond the traditional use of alkylating agents and purine analogs into regimens combining these two chemotherapy classes with monoclonal antibodies.

METHODS

This article reviews treatments options for patients with relapsed or refractory CLL.

RESULTS

Several studies have investigated novel agents in treating patients with 17p deletion, TP53 mutation, and fludarabine-refractory CLL, as well as patients with suboptimal response to intense treatment. These investigational agents include rituximab, alemtuzumab, ofatumumab, bendamustine, high-dose methylprednisolone, lenalidomide, lumiliximab, cyclin-dependent kinase inhibitors, small modular immunopharmaceuticals, Bcl-2 inhibitors, and histone deacetylase inhibitors. While these newer drugs and combination therapies have shown promise as treatment options for CLL, additional studies are needed to determine the immunosuppression, toxicities, and infections associated with their use.

CONCLUSIONS

Despite improvement in initial overall response rates, most patients relapse and require further treatment. CLL remains incurable with standard therapies due to development of disease refractoriness. As such, novel approaches such as those noted above warrant continued research to improve outcomes for patients with CLL.

Chronic lymphocytic leukemia: new concepts and emerging therapies

OPINION STATEMENT

Remarkable progress in elucidating the biology of chronic lymphocytic leukemia (CLL) has been made over the last two decades. Improved understanding of CLL has lead to new prognostic tools and therapeutic options, and holds promise for eventually finding a cure for this disease. Challenges lie in incorporating the various treatment modalities, including chemotherapy, monoclonal antibodies, immunotherapeutic strategies and novel small molecules, into a comprehensive treatment strategy guided by the biological complexity of CLL.

Five-year follow-up of patients with advanced chronic lymphocytic leukemia treated with allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

PURPOSE

We reported encouraging early results of allogeneic hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning in 64 patients who had advanced chronic lymphocytic leukemia (CLL). Here, we have extended the follow-up to a median of 5 years and have included data on an additional 18 patients.

PATIENTS AND METHODS

Eighty-two patients, age 42 to 72 years, who had fludarabine-refractory CLL were conditioned with 2 Gy total-body irradiation alone or combined with fludarabine followed by HCT from related (n = 52) or unrelated (n = 30) donors.

RESULTS

Complete remission (CR) and partial remission were achieved in 55% and 15% of patients, respectively. Higher CR rates were noted after unrelated HCT (67% v 48%). The 5-year incidences of nonrelapse mortality (NRM), progression/relapse, overall survival, and progression-free survival were 23%, 38%, 50%, and 39%, respectively. Among 25 patients initially reported in CR, 8% relapsed and 8% died as a result of NRM, whereas 84% have remained alive and in CR. Among 14 responding patients who were tested and who had molecular eradication of their disease, two died as a result of NRM, two relapsed, and 10 have remained negative. At 5 years, 76% of living patients were entirely well, whereas 24% continued to receive immunosuppression for chronic graft-versus-host disease; the median performance status in each group was 100% and 90%, respectively. Lymphadenopathy > or = 5 cm, but not cytogenetic abnormalities at HCT, predicted relapse. In a risk-stratification model, patients who had lymphadenopathy less than 5 cm and no comorbidities had a 5-year OS of 71%.

CONCLUSION

Nonmyeloablative HCT resulted in a median survival of 5 years for patients who had fludarabine-refractory CLL with sustained remissions and in the continued resolution of chronic graft-versus-host disease in surviving patients.

Emerging therapy for chronic lymphocytic leukaemia

The presentation, clinical course and prognosis for chronic lymphocytic leukaemia (CLL) is diverse and strategies for therapy reflect this variability. Staging of the disease has assisted in deciding treatment options and more recently the cytogenetic, molecular and surrogate markers of the immunoglobulin heavy chain mutational status, CD38 and ZAP-70, have assisted in further risk stratification. Chemotherapy has been the mainstay of interventional therapy when required and the two most important classes of agents in the treatment of CLL are nucleoside analogues and alkylating agents. Combining these two groups of agents has significantly improved prognosis in this disease. More recently a number of novel agents have been applied to patients with CLL to determine if they represent better therapy. However, allogeneic stem cell transplantation offers perhaps the only realistic chance of a cure in this disease. Clinical trials are still needed to determine the timing and role of this promising treatment modality in the treatment of CLL and, where possible, combined with the emerging awareness of the disease biology, related biological markers and prognostic indicators.

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.

How I treat refractory CLL

Therapy for patients with chronic lymphocytic leukemia (CLL) has greatly changed over the past few years. After years of stagnation, with treatment revolving around the use of rather ineffective drugs such as alkylators, many patients are now being treated with more effective agents such as purine analogs either alone or combined with other drugs and/or monoclonal antibodies. Treatment of patients refractory to these treatments is particularly challenging and should be decided only upon a careful evaluation of the disease, patient characteristics, and prognostic factors. Refractory disease should be clearly separated from relapsing disease. The only curative therapy for patients with CLL, including those with refractory disease, is allogeneic stem cell transplantation. However, the use of allogeneic transplantation is limited because of the advanced age of most patients and the high transplant-related mortality (TRM). Transplants with nonmyeloablative regimens may reduce TRM and allow more patients to receive transplants more safely. For patients in whom an allogeneic transplantation is not feasible or in whom it is deemed inappropriate, participation in phase 2 trials should be encouraged. Finally, to investigate mechanisms to overcome resistance to therapy in CLL and to identify patients that might gain benefit from early, intensive therapies (eg, based on biologic markers) constitute a challenge that needs active investigation.

Infections associated with purine analogs and monoclonal antibodies

Nucleoside analogs and monoclonal antibodies are commonly used to treat lymphoproliferative disorders and have become established as the treatment of choice in chronic lymphocytic leukemia, hairy cell leukemia, and follicular lymphomas, as well as a number of other malignant lymphoid neoplasms. When used in standard doses, these agents have a low incidence of extramedullary side effects resulting in their inclusion in a number of combination regimens. The most important complications associated with these drugs are myelosuppression, immunosuppression and infections. This is further accentuated when they are used in combination with other drugs such as alkylating agents. Several investigators have attempted to delineate the risk factors predicting the risk of infections associated with these agents. Furthermore, risk-based strategies to decrease the incidence of these infectious complications have been proposed.

Purine nucleoside analogues and combination therapies in B-cell chronic lymphocytic leukemia: dawn of a new era

Purine nucleoside analogues are unique drugs that are effective in a variety of hematologic malignancies. Fludarabine and 2-chlorodeoxyadenosine (2-CdA) are active in chronic lymphocytic leukemia (CLL) both as salvage therapy and in newly diagnosed patients. These agents have revolutionized therapeutic strategies for patients with CLL that had remained unchanged for many years and included alkylating agents-based therapy with no potential for long-term remission or cure. Purine analogues have also been successfully combined with a variety of other chemotherapeutic drugs such as mitoxantrone, cyclophosphamide, corticosteroids, and monoclonal antibodies, specifically Rituximab and CAMPATH-1H. These agents are immunosuppressive and have been associated with opportunistic infections, the incidence of which can be significantly reduced by early recognition and administration of prophylactic antibiotics. In this review, the activity and toxicity of 2-CdA, fludarabine, and pentostatin in CLL as single agents and in combination with conventional chemotherapy are discussed. These drugs are increasingly used as initial therapy in CLL. Such strategies are associated with higher remission rates than have been previously achieved and in some cases, molecular remission, suggesting an important step towards cure.

Tumor lysis syndrome (TLS) following fludarabine therapy for chronic lymphocytic leukemia (CLL): case report and review of the literature

Adenosine deaminase inhibitors have proven superior to alkylating agent-based therapies in inducing clinical and hematologic remissions in treated and previously untreated chronic lymphocytic leukemia (CLL) patients, and they have become increasingly accepted as a standard for therapy. We report the case of a 66-year-old patient with a 7-year history of CLL who had been previously treated with alkylating agents. Upon presentation with abdominal lymphadenopathy, a 5-day course of the nucleoside analogue, fludarabine, was administered. Two days after completion, the patient developed acute tumor lysis syndrome (TLS) that induced renal failure with hyperkalemia and hyperuricemia. This resulted in critical, life-threatening complications requiring hospitalization, aggressive hemodialysis and fluid replacement therapy. While only 5 other cases of TLS associated with fludarabine therapy have been reported since 1989, we recommend that adenosine deaminase inhibitor therapy be initiated with the addition of allopurinol, and that hydration with copious amounts of oral fluids during therapy be encouraged in order to help protect against the renal effects of potential TLS induced by these agents.

Fludarabine, cyclophosphamide and mitoxantrone in the treatment of resistant or relapsed chronic lymphocytic leukaemia

We evaluated the efficacy and toxicity of fludarabine combined with cyclophosphamide and mitoxantrone (FCM) in patients with relapsed or resistant chronic lymphocytic leukaemia (CLL). In total, 37 patients with recurrent or resistant CLL received FCM: fludarabine 25 mg/m2 intravenously (IV), d 1-3; cyclophosphamide 200 mg/m2 IV, d 1-3; and mitoxantrone 6 mg/m2 IV, d 1, at 4-week intervals for up to six courses. Moreover, 23 patients received FCM with cyclophosphamide 600 mg/m2 i.v. and mitoxantrone 8 mg/m2 i.v. on d 1. In addition to clinical methods, response was assessed using cytofluorometric and molecular techniques. 'In vitro' sensitivity to the FCM regimen was also analysed in 20 samples. The median number of courses given was 3 (range: 1-6). Overall, 30 patients (50%) achieved complete response (CR), including 10 cases of negative minimal residual disease (MRD(-)) (17%), and 17 (28%) partial response (PR). The median duration of response was 19 months. 'In vitro' sensitivity also correlated with CR achievement (P = 0.04). Main toxicity consisted of neutropenia, infections (8% of courses), and nausea and vomiting. The treatment-related mortality was 5%. FCM did not hamper stem cell harvesting in patients who were candidates for autologous stem cell transplantation. FCM induced a high CR rate, including an important number of MRD(-), in patients with previously treated CLL.

Therapy-related myeloid leukemias are observed in patients with chronic lymphocytic leukemia after treatment with fludarabine and chlorambucil: results of an intergroup study, cancer and leukemia group B 9011

PURPOSE

Patients with chronic lymphocytic leukemia (CLL) may have disease transformation to non-Hodgkin's lymphoma or prolymphocytic leukemia; however, development of therapy-related acute myeloid leukemia (t-AML) is unusual. A series of patients enrolled onto an intergroup CLL trial were examined for this complication.

PATIENTS AND METHODS

A total of 544 previously untreated B-cell CLL patients were enrolled onto a randomized intergroup study comparing treatment with chlorambucil, fludarabine, or fludarabine plus chlorambucil. Case report forms from 521 patients were reviewed for t-AML.

RESULTS

With a median follow-up of 4.2 years, six patients (1.2%) to date have developed therapy-related myelodysplastic syndrome (t-MDS; n = 3), t-AML (n = 2), or t-MDS evolving to t-AML (n = 1), from 27 to 53 months (median, 34 months) after study entry. This included five (3.5%) of 142 patients treated with fludarabine plus chlorambucil and one (0.5%) of 188 receiving fludarabine; no chlorambucil-treated patients developed t-MDS or t-AML (P =.007). At study entry, the median age among these six patients was 56 years (range, 44 to 72 years); three were male; the CLL Rai stage was I/II (n = 4) or III/IV (n = 2). Response to CLL therapy was complete (n = 4) or partial remission (n = 1) and stable disease (n = 1). Marrow cytogenetics, obtained in three of six cases at diagnosis of t-MDS or t-AML, were complex, with abnormalities in either or both chromosomes 5 and 7. Other abnormalities involved chromosomes X, 1, 8, 12, 17, and 19. Median survival after diagnosis of t-MDS/AML was 3.5 months (range, 0.5 to 10.1 months).

CONCLUSION

Our findings raise the possibility that alkylator-purine analog combination therapy may increase the risk of therapy-related myeloid malignancies, which is of particular relevance with regard to ongoing trials using these combination therapies.

B-chronic lymphocytic leukemia: practical aspects

B-CLL is the most common adult leukemia in the Western world. It is a neoplasia of mature looking B-monoclonal lymphocytes co-expressing the CD5 antigen (involving the blood, the bone marrow, the lymph nodes and related organs). Much new information about the nature of the neoplastic cells, including chromosomal and molecular changes as well as mechanisms participating in the survival of the leukemic clone have been published recently, in an attempt to elucidate the biology of the disease and identify prognostic subgroups. For the time being, clinical stage based on Rai and Binet staging systems remains the strongest predictor of prognosis and patients' survival, and therefore it affects treatment decisions. In the early stages treatment may be delayed until progression. When treatment is necessary according to well-established criteria, there are nowadays many different options. Chlorambucil has been the standard regimen for many years. During the last decade novel modalities have been tried with the emphasis on fludarabine and 2-chlorodeoxyadenosine and their combinations with other drugs. Such an approach offers greater probability of a durable complete remission but no effect on overall survival has been clearly proven so far. Other modalities, included in the therapeutic armamentarium, are monoclonal antibodies, stem cell transplantation (autologous or allogeneic) and new experimental drugs. Supportive care is an important part of patient management and it involves restoring hypogammaglobulinemia and disease-related anemia by polyvalent immunoglobulin administration and erythropoietin respectively.

Chronic lymphocytic leukemia: case-based session

Drs. Hartmut Döhner, Michael J. Keating, Kanti R. Rai and Emili Montserrat form the panel to review chronic lymphocytic leukemia (CLL) while focusing on the clinical features of a particular patient. The pace of progress in CLL has accelerated in the past decade. The pathophysiological nature of this disease, as had been known in the past, was based largely on the intuitive and empiric notions of two leaders in hematology, William Dameshek and David Galton. Now the works of a new generation of leaders are providing us with the scientific explanations of why CLL is a heterogeneous disease, perhaps consisting of at least two separate entities. In one form of CLL, the leukemic lymphocytes have a surface immunoglobulin (Ig) variable region gene that has undergone somatic mutations, with tell-tale markers suggesting that these cells had previously traversed the germinal centers. Such patients have a distinctly superior prognosis than their counterparts whose leukemic lymphocytes IgV genes have no mutations (these are indeed immunologically naive cells), who have a worse prognosis. The introduction of fluorescence in situ hybridization (FISH) technique has provided us with new insights into the diverse chromosomal abnormalities that can occur in CLL, and which have significant impact on the clinical behavior and prognosis of patients with this disease. Major advances in therapeutics of CLL also have occurred during the past decade. Two monoclonal antibodies, Campath-1H (anti-CD52) and rituximab (anti-CD20), and one nucleoside analogue, fludarabine, have emerged as three agents of most promise in the front-line treatment of this disease. Studies currently in progress reflect our attempts to find the most effective manner of combining these agents to improve the overall survival statistics for CLL patients. As in many other hematological malignancies, high dose chemotherapy followed by autologous or HLA-compatible allogeneic stem cells rescue strategies are under study as a salvage treatment for a relatively younger age group of CLL patients with poor prognosis characteristics.

Significance of the levels of bone marrow lymphoid infiltrate in chronic lymphocytic leukemia patients with nodular partial remission

Patients with chronic lymphocytic leukemia (CLL) are considered in nodular partial remission (nPR) when they are in remission but bone marrow biopsies show rare nodules. The significance of the level of residual disease in nPR is not known. We studied 91 previously untreated CLL patients who were treated with fludarabine alone, fludarabine with prednisone, or fludarabine with cyclophosphamide and achieved nPR at the end of six courses. We compared bone marrow lymphoid infiltration before therapy and at the end of three and six courses of therapy as evaluated by a pathologist in retrospective fashion with that of the routine evaluation at the time of performing bone marrow biopsy. We then compared these results with those obtained by computer-aided histomorphometry in 28 patients in nPR. There was significant correlation (P < 0.05) between pathologists as well as between pathologists and histomorphometry. Upon correlation with clinical characteristics, there was significant correlation (P 0.01) between marrow involvement before therapy and white blood cell counts (wbc), hemoglobin (hgb), absolute lymphocyte counts, and beta2-microglobulin (beta2-m) but none of these parameters correlated with the lymphoid infiltrate at the end of three or six courses of therapy. more importantly, lymphoid infiltration after three and six courses did not correlate with time to progression (ttp) or overall survival (os). however, patients with >70% marrow involvement before therapy had a significantly shorter TTP (P = 0.02). All 91 patients showed similar results. However, we found reverse correlation between marrow lymphoid infiltrate at the end of three courses and OS (P = 0.01).

Activity of oral fludarabine phosphate in previously treated chronic lymphocytic leukemia

PURPOSE

A prospective, multicenter, open-label phase II clinical trial was conducted to assess the efficacy and safety of oral fludarabine phosphate. Reference to an historical group of patients treated with the intravenous (IV) formulation allowed the investigators to compare the two formulations.

PATIENTS AND METHODS

Efficacy was assessed using the International Workshop on Chronic Lymphocytic Leukemia (IWCLL) and National Cancer Institute (NCI) criteria for complete remission (CR), partial remission (PR), stable disease, or disease progression. Safety monitoring included World Health Organization (WHO) toxicity grading for all adverse events.

RESULTS

Seventy-eight (96.3%) of 81 recruited patients with previously treated B-cell chronic lymphocytic leukemia (CLL) received 10-mg tablets of fludarabine phosphate to a dose of 40 mg/m(2)/d for 5 days, repeated every 4 weeks, for a total of six to eight cycles. According to IWCLL criteria, the overall remission rate was 46.2% (CR, 20.5%; PR, 25.6%). The comparative figures using NCI criteria were 51.3% (CR, 17.9%; PR, 33.3%). Overall, 30 incidents of severe adverse events were reported for 22 patients. WHO grade 3 or grade 4 hematologic toxicities included granulocytopenia (53.8%), leukocytopenia (28.2%), thrombocytopenia (25.6%), and anemia (24.4%). Gastrointestinal adverse events were more common with the oral formulation than previously reported with IV fludarabine phosphate. However, these events were generally mild to moderate.

CONCLUSION

This study demonstrates that oral fludarabine phosphate has similar clinical efficacy to the IV formulation and a safety profile that is both predictable and essentially similar to that of the IV formulation.

Peripheral blood stem cell (PBSC) mobilization and transplantation after fludarabine therapy in chronic lymphocytic leukaemia (CLL): a report of the European Blood and Marrow Transplantation (EBMT) CLL subcommittee on behalf of the EBMT Chronic Leukaemias Working Party (CLWP)

We performed a survey from 122 centres of the European Group of Blood and Marrow Transplantation (EBMT) concerning peripheral blood stem cell (PBSC) mobilization after fludarabine treatment of patients with chronic lymphocytic leukaemia (CLL). A total of 101 leucaphereses from 29 patients was performed. The median cell numbers collected were: CD34+ cells, 2.2 x 106/kg (0.1-15.3); granulocyte-macrophage colony-forming units (GM-CFU), 4.29 x 104/kg (0.4-177); and mononuclear cells, 6.4 x 108/kg (1.3-63). In univariate and multivariate analyses, the numbers of cells collected were not significantly influenced by the nature of mobilizing regimen and there was a trend towards the collection of a higher number of CD34+ cells from patients who received fludarabine only before mobilization. There was a significant correlation between the median number of CD34+ cells collected and the number of courses of fludarabine (higher CD34+ cell numbers were related to more than six courses) and the interval between the last dose of fludarabine and the start of mobilizing therapy (higher CD34+ cell numbers were related to a delay > or = 2 months). Sixteen patients have subsequently undergone autologous transplantation and showed rapid engraftment. In conclusion, the results reported favour early stem cell mobilization in CLL patients who are in remission after first-line therapy. However, attention should be given to the timing of mobilization with respect to the time since the last dose of fludarabine.

Management of chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is the most common form of adult leukaemia in Western countries. The diagnosis requires mature-appearing lymphocytes in the peripheral blood to >5 x 10(9)/L. The immunophenotype typically includes B cell antigens CD19, CD20 and CD23, low expression of surface immunoglobulin and CD5+, with other T cell antigens absent. Bone marrow biopsy, although not required for diagnosis, must show at least 30% lymphocytes. Cytogenetic abnormalities are frequent in patients with CLL, and may be associated with poor prognosis. Clinically, most patients are asymptomatic at presentation, with incidental lymphadenopathy and/or hepatosplenomegaly in the routine physical examination. Infections by opportunistic pathogens are the major cause of death. Aggressive transformation occurs in 10% of patients with CLL, most commonly prolymphocytic leukaemia (PLL) and Richter's syndrome. PLL de novo must be differentiated from PLL of an aggressive transformation. The incidences of autoimmune diseases and solid or haemopoietic secondary malignancies are increased in patients with CLL. Clinical stage is the strongest prognostic factor in CLL. There is no indication for early intervention. The current recommendation to start treatment includes disease-related symptoms, massive and/or progressive hepatosplenomegaly or lymphadenopathy, increasing bone marrow failure, autoimmune disease, and recurrent infections. Alkylating agents (e.g. chlorambucil) and nucleoside analogues (e.g. fludarabine) are the most active agents for CLL. Fludarabine induces higher response rates, but no improvement in overall survival has been observed. Fludarabine is the drug of choice for the majority of patients with CLL. Chlorambucil may be helpful for elderly patients with poor performance, and for patients who do not tolerate fludarabine. No drug combination is better than single agents. For patients refractory to initial treatment, referral to a clinical trial is the best choice. Other salvage therapy includes retreatment with the same initial agent (chlorambucil or fludarabine) if initial response was observed, or fludarabine for patients refractory to chlorambucil. Promising new approaches include cycle-active agents, nelarabine, biological therapy such as anti-CD52 monoclonal antibody, bone marrow transplantation, including the use of submyeloablative preparative regimens ('minitransplant') to induce graft-versus-leukaemia effect, and gene therapy. Prophylactic antibacterials and intravenous immunoglobulin should not be used routinely during supportive care. Epoetin may be helpful for patients who have anaemia without obvious cause. Assessment of response to therapy in CLL has been updated by the National Cancer Institute Working Group, and these guidelines are used worldwide for clinical trials.

Long-Term Follow-Up of Patients With Chronic Lymphocytic Leukemia (CLL) Receiving Fludarabine Regimens as Initial Therapy

One hundred seventy-four patients with progressive or advanced chronic lymphocytic leukemia (CLL) have received initial therapy with fludarabine as a single agent or fludarabine combined with prednisone. The overall response rate was 78% and the median survival was 63 months. No difference in response rate or survival was noted in the 71 patients receiving fludarabine as a single agent compared with the 103 patients who received prednisone in addition. The median time to progression of responders was 31 months and the overall median survival was 74 months. Patients over the age of 70 years had shorter survivals. Patients with advanced stage disease (Rai III and IV) had a somewhat shorter survival than earlier stage patients. More than half the patients who relapsed after fludarabine therapy responded to salvage treatment, usually with fludarabine-based regimens. Second remissions were more common in patients who had achieved a complete remission on their initial treatment. The CD4 and CD8 T-lymphocyte subpopulations decreased to levels in the range of 150 to 200/μL after the first 3 courses of treatment. Although recovery towards normal levels was slow, the incidence of infections was low in patients in remission (1 episode of infection for every 3.33 patient years at risk) and decreased with time off treatment. There was no association of infections or febrile episodes with the use of corticosteroids or the CD4 count at the end of treatment and a poor correlation with the increase in CD4 counts during remission. Infectious episodes were less common in patients who had a complete response compared with partial responders. Richter’s transformation occurred in 9 patients and Hodgkin’s disease occurred in 4 patients. Five other patients died from other second malignancies. Fludarabine appears to be an effective initial induction therapy with a reasonable safety profile for patients with CLL.

© 1998 by The American Society of Hematology.

Long-Term Follow-Up of Patients With Chronic Lymphocytic Leukemia (CLL) Receiving Fludarabine Regimens as Initial Therapy

One hundred seventy-four patients with progressive or advanced chronic lymphocytic leukemia (CLL) have received initial therapy with fludarabine as a single agent or fludarabine combined with prednisone. The overall response rate was 78% and the median survival was 63 months. No difference in response rate or survival was noted in the 71 patients receiving fludarabine as a single agent compared with the 103 patients who received prednisone in addition. The median time to progression of responders was 31 months and the overall median survival was 74 months. Patients over the age of 70 years had shorter survivals. Patients with advanced stage disease (Rai III and IV) had a somewhat shorter survival than earlier stage patients. More than half the patients who relapsed after fludarabine therapy responded to salvage treatment, usually with fludarabine-based regimens. Second remissions were more common in patients who had achieved a complete remission on their initial treatment. The CD4 and CD8 T-lymphocyte subpopulations decreased to levels in the range of 150 to 200/μL after the first 3 courses of treatment. Although recovery towards normal levels was slow, the incidence of infections was low in patients in remission (1 episode of infection for every 3.33 patient years at risk) and decreased with time off treatment. There was no association of infections or febrile episodes with the use of corticosteroids or the CD4 count at the end of treatment and a poor correlation with the increase in CD4 counts during remission. Infectious episodes were less common in patients who had a complete response compared with partial responders. Richter’s transformation occurred in 9 patients and Hodgkin’s disease occurred in 4 patients. Five other patients died from other second malignancies. Fludarabine appears to be an effective initial induction therapy with a reasonable safety profile for patients with CLL.

© 1998 by The American Society of Hematology.