New agents in chronic lymphocytic leukemia

Opinion statement For many years, alkylating agents, especially chlorambucil, have been considered the drugs of choice for first-line treatment of progressive and symptomatic chronic lymphocytic leukemia (CLL). More recently, treatment approaches have included purine nucleoside analogs (PNAs), fludarabine or cladribine (2-CdA), and monoclonal anti-bodies (MoAbs). PNAs are highly active in patients with CLL, previously treated and untreated. Significantly higher overall response and complete response in patients treated initially with fludarabine or 2-CdA than in those treated with chlorambucil- or cyclophosphamide-based combination regimens have been recently confirmed in prospective, randomized trials. However, the median survival times do not differ among the patients treated with PNA and alkylating agents. The MoAbs directed against CD52 antigen (alemtuzumab) and CD20 antigen (rituximab) also demonstrate significant activity in CLL and should be used in patients with disease that is refrac-tory to PNAs. Combination therapies with PNAs and cyclophosphamide, and especially with rituximab, are more active than monotherapy with PNAs in regard to response rate and possible survival. Because most patients are older and there is no survival time advantage for alkylating agents or PNA therapies, we recommend chlorambucil as the first-line treatment, with PNAs for consideration as the second-line therapy. PNAs alone or in combination with cyclophosphamide and rituximab as first-line treatment are an option in younger patients, who may be candidates for consolidation therapy with alemtuzumab and/or stem cell transplantation. Alemtuzumab may be an effective treatment for patients refractory to PNAs. Several biological parameters have been gaining increasing importance to evaluate the prognosis of patients with CLL and define optimal therapeutic strategy. Moreover, novel therapies are being evalu-ated, especially in patients refractory to PNAs, including those targeting the anti-apoptotic bcl-2 family of proteins and receptors, vaccines, and allogenic stem cell transplantation, especially after nonmyeloablative chemotherapy.     

What is the optimal initial treatment for chronic lymphocytic leukemia?

For decades, initial therapy for chronic lymphocytic leukemia (CLL) consisted of alkylators such as chlorambucil (Leukeran). The introduction of nucleoside analogs such as fludarabine and monoclonal antibodies such as rituximab (Rituxan) markedly changed the initial therapy of CLL, particularly in the United States. Fludarabine and combination regimens such as fludarabine/cyclophosphamide (FC) have achieved higher complete response (CR) rates and progression-free survival (PFS) than chlorambucil in previously untreated CLL, but long-term overall survival has not improved, due to concurrent improvement in salvage therapy of relapsed CLL patients. Upfront chemoimmunotherapy regimens such as fludarabine/rituximab (FR) and fludarabine/cyclophosphamide/rituximab (FCR) have similarly improved CR rates and PFS in previously untreated CLL patients, but it is unclear whether overall survival is improved. Advances in cytogenetic analysis and other biologic prognostic factors have greatly enhanced clinicians' ability to risk-stratify newly diagnosed CLL patients, and knowledge of such prognostic factors is necessary to properly interpret results of clinical treatment studies. The choice of initial therapy for an individual patient should depend upon the patient's age and medical condition, cytogenetic and other prognostic factors, and whether the goal of therapy is maximization of CR and PFS or palliation of symptoms with minimal toxicity.     

Screening and early diagnosis in lung cancer

Over the last few years, several monoclonal antibodies have been investigated in patients with B-cell lymphoid malignancies. Rituximab is the most important monoclonal antibody of clinical value in these disorders. Rituximab is an IgG1 chimeric antibody containing murine light- and heavy-chain variable region sequences and human constant region sequences. Since approval in 1997, rituximab has become the standard of care in follicular B-cell lymphoma, chronic lymphocytic leukemia (CLL) and aggressive lymphoma when combined with chemotherapy. Higher clinical benefits of rituximab can be seen in patients with CLL when it is added to other chemotherapeutic agents. Several recent reports have suggested that in patients with CLL, rituximab combined with purine nucleoside analogs (PNAs) or PNAs and cyclophosphamide may improve the results with acceptable toxicity, both in previously untreated and refractory/relapsed patients. The randomized, multinational Phase III study (REACH trial) has shown that rituximab combined with fludarabine and cyclophosphamide (R-FC regimen) results in 10 months longer progression-free survival, and higher overall response and complete response rates than fludarabine and cyclophosphamide (FC regimen) in previously treated patients. The German CLL study group initiated a multicenter, multinational Phase III trial, CLL8, to evaluate the efficacy and tolerability of R-FC versus FC for the first-line treatment of patients with advanced CLL. The overall response rate was significantly higher in the R-FC arm (95%) compared with FC (88%). The complete response rate in the R-FC arm was 44% compared with 27% in the FC arm. The recently updated analysis has demonstrated longer overall survival in the R-FC group. Recent clinical observations have revealed that combinations of rituximab with pentostatin and cyclophosphamide, or cladribine and cyclophosphamide are also highly active regimens in previously untreated CLL. In addition, the results of treatment with high-dose methylprednisolone in combination with rituximab in advanced CLL resistant to fludarabine have been reported recently by several groups. However, available therapies are only partially effective in CLL, exposing an obvious need to develop new, more specific and active drugs. Recently, several new anti-CD20 monoclonal antibodies have been developed and are now being evaluated in clinical trials.     

Rituximab plus fludarabine and cyclophosphamide or other agents in chronic lymphocytic leukemia

Over the last few years, several monoclonal antibodies have been investigated in patients with B-cell lymphoid malignancies. Rituximab is the most important monoclonal antibody of clinical value in these disorders. Rituximab is an IgG1 chimeric antibody containing murine light- and heavy-chain variable region sequences and human constant region sequences. Since approval in 1997, rituximab has become the standard of care in follicular B-cell lymphoma, chronic lymphocytic leukemia (CLL) and aggressive lymphoma when combined with chemotherapy. Higher clinical benefits of rituximab can be seen in patients with CLL when it is added to other chemotherapeutic agents. Several recent reports have suggested that in patients with CLL, rituximab combined with purine nucleoside analogs (PNAs) or PNAs and cyclophosphamide may improve the results with acceptable toxicity, both in previously untreated and refractory/relapsed patients. The randomized, multinational Phase III study (REACH trial) has shown that rituximab combined with fludarabine and cyclophosphamide (R-FC regimen) results in 10 months longer progression-free survival, and higher overall response and complete response rates than fludarabine and cyclophosphamide (FC regimen) in previously treated patients. The German CLL study group initiated a multicenter, multinational Phase III trial, CLL8, to evaluate the efficacy and tolerability of R-FC versus FC for the first-line treatment of patients with advanced CLL. The overall response rate was significantly higher in the R-FC arm (95%) compared with FC (88%). The complete response rate in the R-FC arm was 44% compared with 27% in the FC arm. The recently updated analysis has demonstrated longer overall survival in the R-FC group. Recent clinical observations have revealed that combinations of rituximab with pentostatin and cyclophosphamide, or cladribine and cyclophosphamide are also highly active regimens in previously untreated CLL. In addition, the results of treatment with high-dose methylprednisolone in combination with rituximab in advanced CLL resistant to fludarabine have been reported recently by several groups. However, available therapies are only partially effective in CLL, exposing an obvious need to develop new, more specific and active drugs. Recently, several new anti-CD20 monoclonal antibodies have been developed and are now being evaluated in clinical trials.     

A phase II study of sequential combination chemotherapy with cyclophosphamide, prednisone, and 2-chlorodeoxyadenosine in previously untreated patients with chronic lymphocytic leukemia.

In an earlier study of previously untreated patients with chronic lymphocytic leukemia (CLL), we used a concomitant combination of chlorambucil and 2-chlorodeoxyadenosine and reported overall (OR) and complete (CR) remission rates of 80% and 20%, respectively. After a median follow-up of 5 years, more than 80% of the responders have had a relapse. In the current phase II study of 27 previously untreated patients with CLL, we used a sequential combination of six cycles of intravenous cyclophosphamide (1 g/m2) plus oral prednisone (100 mg/m2 per day for 5 days) followed by two to six cycles of 2-chlorodeoxyadenosine (5 mg/m2 per day for 5 days). The OR and CR rates were 96% and 33%, respectively. After a median follow-up of 29 months, 35% of the responders have had a relapse. Progression-free survival was significantly better in CR patients than in those with partial remission. However, minimal residual disease was phenotypically detected in four of the nine CR patients. Despite the fact that the current OR and CR rates are superior to those seen in a historical cohort treated with a concomitant schedule, a longer follow-up period is needed to assess the durability of these remissions, and a controlled trial is necessary to estimate the impact on overall survival and toxicity.     

Results of the fludarabine and cyclophosphamide combination regimen in chronic lymphocytic leukemia.

PURPOSE: To assess the efficacy of combination therapy with fludarabine and cyclophosphamide in patients with chronic lymphocytic leukemia (CLL) based on data suggesting in vitro synergistic activity of the two agents. PATIENTS AND METHODS: A total of 128 patients with CLL were treated with fludarabine 30 mg/m(2) intravenously daily for 3 days and cyclophosphamide at either 500 mg/m(2) daily for 3 days (n = 11), 350 mg/m(2)/d for 3 days (n = 26), or 300 mg/m(2) daily for 3 days (n = 91). The cyclophosphamide dose was decreased because of myelosuppression in the early part of the study. Patients were divided into four groups based on the expectation for response to single-agent fludarabine, including previously untreated patients, patients previously treated with alkylating agents, patients successfully treated with alkylating agents and fludarabine but relapsing, and patients refractory to fludarabine with or without alkylating agents. RESULTS: Fludarabine and cyclophosphamide produced > or = 80% response rates in all patients not refractory to fludarabine at the start of therapy as well as a 38% response rate in patients who were refractory to fludarabine. The complete remission (CR) rate was 35% in previously untreated patients, which was not significantly different from the CR rate in historical control patients treated with single-agent fludarabine. However, residual disease assessed by flow cytometry occurred in only 8% of previously untreated patients achieving CR, and median time to progression has not been reached after a median follow-up of 41 months. The main complication of therapy was related to myelosuppression and infection. Neutropenia to less than 500 x 10(9)/L was noted in 48% of patients who received cyclophosphamide 300 mg/m(2). Pneumonia or sepsis occurred in 25% of patients, and fever of unknown origin occurred in another 25%. Pneumonia or sepsis were significantly more frequent in patients who were refractory to fludarabine at the start of combination chemotherapy. CONCLUSION: Fludarabine and cyclophosphamide seem to have a significant advantage over single-agent fludarabine in the salvage setting. Although the CR rate was not increased in previously untreated patients, residual disease detected by flow cytometry was rare and remission durations seemed to be prolonged in this subset. Myelosuppression and infection remain the most significant complications of therapy in CLL.     

Fludarabine and mitoxantrone for patients with chronic lymphocytic leukemia

BACKGROUND: The objective of the current study was to assess the efficacy of combination therapy with fludarabine and mitoxantrone in patients with B-cell chronic lymphocytic leukemia (CLL). METHODS: Eighty-eight patients were treated with fludarabine 30 mg/m(2) intravenously daily for 3 days and mitoxantrone 10 mg/m(2) on Day 1 (FN). Patients were divided into four groups based on expected response to single-agent fludarabine. These four groups included previously untreated patients, patients who previously were treated with alkylating agents, patients who were successfully treated with alkylating agents and fludarabine but who developed recurrent disease, and patients whose disease was refractory to fludarabine with or without alkylating agents. RESULTS: The overall response rate was 66%. The response rates were 83% in previously untreated patients, 87% in patients previously treated with alkylating agents, 50% in patients whose disease was not refractory to fludarabine at the start of therapy, and 25% in patients whose disease was refractory to fludarabine. The complete remission (CR) rate was 20% for previously untreated patients, which was not significantly different from the CR rate for a group of historical control patients who were treated with single-agent fludarabine. The median follow-up was 8 years for surviving patients. The median progression free survival was 24 months for all patients and 34 months for previously untreated patients. The median overall survival was 40 months, and the median survival of previously untreated patients was 88 months. The most common toxicities were myelosuppression and infection. Eleven patients (12.5%) developed a second malignancy after a median of 62 months. CONCLUSIONS: The FN regimen did not have a significant advantage over fludarabine alone in the treatment of patients with CLL.     

Long-Term Results of CAP Therapy in Chronic Lymphocytic Leukemia

This study was designed to study the efficacy and toxicity of an adriamycin-containing regimen (CAP: cyclophosphamide, adriamycin, and prednisone) in patients with previously untreated chronic lymphocytic leukemia (CLL). CAP was given to clinical complete remission followed by 18 months of cyclophosphamide-prednisone (CP) maintenance. Forty-seven patients with previously untreated CLL were treated. These patients initially presented with advanced stage (Rai III or IV) or had less advanced stage (Rai 0-II) patients and demonstrated evidence of disease progression. Patients received 750 mg/m² of cyclophosphamide intravenously on day 1, 50 mg/m² of adriamycin intravenously on day 1 and 100 mg/day of prednisone on days 1-5. Courses were repeated at 3-week intervals until clinical CR, at which time maintenance with cyclophosphamide and prednisone (CP) was commenced. A maximum cumulative dose of 450 mg/m² of adriamycin (9 courses of CAP) was given. Twenty (43%) of 47 patients obtained a CR and 11 (23%) obtained a partial remission. Bone marrow biopsy criteria were used to define response in addition to clinical and peripheral blood responses. All patients have been followed for 10 years. The median survival was 259 weeks. No patient remains in remission. No impact of response on survival was found. Surprisingly, the response rate and survival were higher and longer for patients with more advanced stages and higher tumor burdens. The median survival times for patients with Rai stage IV and Binet stage C disease were 93 months and 81 months, respectively. Although the regimen was well tolerated, three patients, each with an antecedent cardiac risk factor, developed congestive heart failure. Adriamycin containing regimens can be safely given to elderly patients with CLL and show promise in the treatment of advanced stage disease.     

Consolidation therapy with high-dose cyclophosphamide improves the quality of response in patients with chronic lymphocytic leukemia treated with fludarabine as induction therapy.

Fludarabine is the most active agent in the treatment of chronic lymphocytic leukemia (CLL). Despite this activity only a minority of patients treated with fludarabine achieve a complete response. We evaluated a new treatment program of sequential therapy with fludarabine followed by high-dose cyclophosphamide in previously untreated patients with CLL. This report details the results in 25 patients with previously untreated CLL. Patients received fludarabine (25 mg/m2/day x 5 days every 4 weeks for six cycles) as induction followed by consolidation with high-dose cyclophosphamide at one of three dose levels 1.5 g/m2, 2.25 g/m2, or 3 g/m2 administered every 2 weeks for three doses. High-dose cyclophosphamide was given with G-CSF support (5 microg/kg/day days 3-12). Complete response (CR) required a normal physical examination, normal CBC, a normal bone marrow evaluation including no residual lymphoid nodules on biopsy. A nodular response was defined as a complete response with the exception of an occasional residual nodule seen on bone marrow biopsy. Flow cytometric analysis for CD5:CD19 dual staining and kappa/lambda clonal excess was performed in all patients as a sensitive measure of minimal residual disease (MRD). Selected patients had patient/tumor-specific oligonucleotides generated that were subsequently used in a polymerase chain reaction as an extremely sensitive measure of MRD. There were no treatment-related deaths and no patient encountered unacceptable toxicity. After completion of this sequential regimen 76% (95% confidence interval: 59-93%) of patients had a major response: eight (32%) achieved a CR, four (16%) a nodular response, seven (28%) a PR, and six patients (24%) failed. Four patients withdrew from study during induction with fludarabine and did not receive at least one cycle of cyclophosphamide. Of the 21 patients who received consolidation with cyclophosphamide 10 (48%) had an improved quality of response when compared to that achieved with fludarabine. Two patients (8%) had no disease detectable by flow cytometry ('flow cytometric' CR) after six cycles of fludarabine. This improved to nine patients (36%) after high-dose cyclophosphamide. Following consolidation with high-dose cyclophosphamide three patients (12%) tested negative by PCR. All of these patients had morphologic evidence of residual disease after six cycles of fludarabine. Consolidation with high-dose cyclophosphamide increased the fraction of patients achieving a nodular response or CR three-fold (16% to 48%). This appears to be clinically relevant because with a median follow-up of 52 (range 34-78) months the projected 6-year survival for patients achieving a CR or NR is 91% compared to 41% for all others (P = 0.012). We conclude that sequential therapy with fludarabine followed by high-dose cyclophosphamide in previously untreated patients with CLL is safe and can improve the quality of response in a large proportion of patients compared to therapy with fludarabine alone.     

Low‐dose fludarabine and cyclophosphamide combined with standard dose rituximab (LD‐FCR) is an effective and safe regimen for elderly untreated patients with chronic lymphocytic leukemia: The Israeli CLL study group experience

Chronic lymphocytic leukemia (CLL) is a disease of elderly patients. The fludarabine, cyclophosphamide, and rituximab (FCR) regimen is considered the treatment of choice for young fit patients with CLL; however, this combination is toxic for older patients. At the time this study was first planned and initiated, there was no standard chemo‐immunotherapy regimen regarded as standard therapy for the less fit elderly patient with CLL. Here, we conducted a single‐arm, phase II trial to examine the efficacy and safety of lower‐dose fludarabine and cyclophosphamide combined with a standard dose of rituximab (LD‐FCR) in elderly patients with previously untreated CLL. Forty patients received LD‐FCR and were included in the efficacy analysis. Two patients treated with FC alone were only included in the safety analysis. The median age was 72.7 years (range, 65.0 to 85.0). The overall response and complete response rates were 67.5% and 42.5%, respectively. Median progression‐free survival (PFS) was 35.5 months (95% CI, 29.27‐41.67). Two patients (4.8%) died during the study period. Hematological toxicities and infections were the most common complications encountered; grade 3 to 4 treatment‐related neutropenia occurred in 20 (47.6%) patients. During the entire study follow‐up, 26 patients (61.9%) had all grades of infection including six (14.3%) with neutropenic fever and eight (19%) with grade 3 to 4 non‐neutropenic infections. In conclusion, LD‐FCR is an effective and relatively safe regimen for previously untreated patients with CLL. It has the advantage of being both “time and cost limited” and, even in the era of novel agents, can still be considered when planning treatment for elderly patients without high‐risk biomarkers. However, recent results in fit elderly patients using the combination of bendamustine and rituximab which have achieved longer PFS with good safety profile must be taken into consideration in this regard.     

Treatment of fludarabine‐refractory chronic lymphocytic leukemia

The development of resistance to purine analogs defines a poor‐risk subset of patients with chronic lymphocytic leukemia (CLL). Although in recent years chemoimmunotherapeutic combinations such as fludarabine, cyclophosphamide, and rituximab have induced response rates of 95% in previously untreated patients and increased the rates of failure‐free survival, CLL remains incurable for many patients because of a lack of disease response or the development of refractoriness to fludarabine. Fludarabine‐refractory disease is defined as CLL that does not respond to fludarabine or that recurs within 6 months of treatment with a fludarabine‐containing regimen. The natural course of the disease is associated with poor survival. Salvage therapeutic strategies include alemtuzumab‐containing regimens, targeted agents, and allogeneic stem cell transplantation. Single‐agent alemtuzumab induces response in up to 40% of patients with fludarabine‐refractory CLL, but responses are not durable, and the median survival is approximately 1 to 2 years. Alemtuzumab is also combined with fludarabine, cyclophosphamide, and/or rituximab, and other agents such as lenalidomide and flavopiridol, as well as targeted agents, and used in fludarabine‐refractory CLL. Cumulative evidence suggests that allogeneic stem cell transplantation is an efficacious therapeutic strategy for patients who do not respond to fludarabine or who develop disease recurrence within 12 months after purine analog treatment. In conclusion, chemoimmunotherapy regimens that include alemtuzumab and/or rituximab and allogeneic stem cell transplantation improve the prognosis of this disease, but there is a continued need for novel, more effective therapies. Cancer 2009. © 2009 American Cancer Society.     

U.S. Food and drug administration approval: rituximab in combination with fludarabine and cyclophosphamide for the treatment of patients with chronic lymphocytic leukemia

Purpose.

To describe the clinical studies that led to the FDA approval of rituximab in combination with fludarabine and cyclophosphamide (FC) for the treatment of patients with chronic lymphocytic leukemia (CLL).

Materials and Methods.

The results of two multinational, randomized trials in CLL patients comparing rituximab combined with fludarabine and cyclophosphamide versus FC were reviewed. The primary endpoint of both studies was progression-free survival (PFS).

Results.

The addition of rituximab to FC decreased the risk of a PFS event by 44% in 817 previously untreated patients and by 24% in 552 previously treated patients. Median survival times could not be estimated. Exploratory analysis in patients older than 70 suggested that there was no benefit to patients when rituximab was added to FC. The safety profile observed in both trials was consistent with the known toxicity profile of rituximab, FC, or CLL.

Conclusions.

On the basis of the demonstration of clinically meaningful prolongation of PFS, the FDA granted regular approval to rituximab in combination with FC for the treatment of patients with CLL. The magnitude of the treatment effect in patients 70 years and older is uncertain.     

Rituximab plus Short-Duration Chemotherapy Followed by Yttrium-90 Ibritumomab Tiuxetan as First-Line Treatment for Patients with Follicular Non-Hodgkin Lymphoma: A Phase II Trial of the Sarah Cannon Oncology Research Consortium

PurposeTo evaluate the efficacy and safety of treatment with Yttrium-90 (90Y) ibritumomab tiuxetan following completion of short-course rituximab/chemotherapy in patients with previously untreated follicular non-Hodgkin lymphoma.Patients and MethodsForty-one patients with previously untreated follicular lymphoma received rituximab for 4 consecutive weeks, followed by 3 cycles of rituximab combined with either CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone; 88%) or CVP (cyclophosphamide/ vincristine/prednisone; 12%). To complete treatment, all patients received 90Y ibritumomab tiuxetan 4-6 weeks after the final dose of chemotherapy. The primary efficacy endpoint was the clinical complete response (CR) rate after completion of therapy; all patients were followed for progression-free survival (PFS) and overall survival (OS).ResultsAfter completion of shortcourse rituximab/chemotherapy, 95% had objective responses, with a 30% clinical CR rate. The clinical CR rate increased to 72% following 90Y ibritumomab tiuxetan. After a median follow-up of 67 months, the estimated 5-year PFS and OS rates are 64% and 96%, respectively. Reversible grade 3/4 neutropenia and thrombocytopenia occurred in 39% and 36% of the patients, respectively, following 90Y ibritumomab tiuxetan; nonhematologic toxicity was uncommon.Conclusion90Y ibritumomab tiuxetan was well tolerated after short-course rituximab/chemotherapy and resulted in a high CR rate and a long PFS. Definitive demonstration of improved efficacy versus rituximab/chemotherapy alone will require a randomized phase III trial.     

Cladribine in the treatment of chronic lymphocytic leukemia.

Cladribine (2-chlorodeoxyadenosine, 2-CdA) is a nucleoside analog with substituted halogen atom at position 2 in its purine ring that makes it resistant to deamination by adenosine deaminase (ADA). 2-CdA is the drug of choice in the treatment of hairy cell leukemia, but it is also highly active in other low grade lymphoid malignancies including chronic lymphocytic leukemia (CLL). The results of the studies presented so far have shown that 2-CdA gives similar complete response (CR) rate and overall response (OR) rate to fludarabine but the influence of both agents on survival times of the patients with CLL is still uncertain. CR rate induced with 2-CdA is significantly higher than in the patients treated with conventional chemotherapy. In refractory or relapsed patients 2-CdA induces 31 to 68% of overall responses including CR in 4 to 31%. In previously untreated patients overall remission rates of about 56-82% have been achieved with 2-CdA alone. When 2-CdA was used as primary therapy the CR rate was also significantly higher and ranged from 10% to 47%. Patients who received 2-CdA as their initial therapy and experienced a response lasting at least a year may be successfully treated subsequently with the same agent. A second response has been achieved in 35 to 100% patients treated with this agent for the second time. Despite the fact that 2-CdA gives higher CR and OR rates than conventional chemotherapy, it has not been established whether it has any influence on survival time. However, cross resistance between 2-CdA and FAMP in CLL patients is evident in the majority of studies. Bone marrow suppression with anemia neutropenia and thrombocytopenia are the dose limiting factors for 2-CdA use. These side effects are pronounced in heavily pretreated patients and after multiple courses of therapy. Treatment with this agent also leads to the decrease of the CD4+/CD8+ ratio for an extensive period of time exceeding 12, even up to 24 months. In consequence, infections including opportunistic type, are frequently observed. We suggest, that in patients with CLL, 2-CdA should be used as second line treatment rather than the first line therapy until the final results of ongoing randomized clinical trials are available.     

Cladribine in the Treatment of Chronic Lymphocytic Leukemia

Cladribine (2-chlorodeoxyadenosine, 2-CdA) is a nucleoside analog with substituted halogen atom at position 2 in its purine ring that makes it resistant to deamination by adenosine deaminase (ADA). 2-CdA is the drug of choice in the treatment of hairy cell leukemia, but it is also highly active in other low grade lymphoid malignancies including chronic lymphocytic leukemia (CLL). The results of the studies presented so far have shown that 2-CdA gives similar complete response (CR) rate and overall response (OR) rate to fludarabine but the influence of both agents on survival times of the patients with CLL is still uncertain. CR rate induced with 2-CdA is significantly higher than in the patients treated with conventional chemotherapy. In refractory or relapsed patients 2-CdA induces 31 to 68% of overall responses including CR in 4 to 31%. In previously untreated patients overall remission rates of about 56-82% have been achieved with 2-CdA alone. When 2-CdA was used as primary therapy the CR rate was also significantly higher and ranged from 10% to 47%. Patients who received 2-CdA as their initial therapy and experienced a response lasting at least a year may be successfully treated subsequently with the same agent. A second response has been achieved in 35 to 100% patients treated with this agent for the second time. Despite the fact that 2-CdA gives higher CR and OR rates than conventional chemotherapy, it has not been established whether it has any influence on survival time. However, cross resistance between 2-CdA and FAMP in CLL patients is evident in the majority of studies. Bone marrow suppression with anemia neutropenia and thrombocytopenia are the dose limiting factors for 2-CdA use. These side effects are pronounced in heavily pretreated patients and after multiple courses of therapy. Treatment with this agent also leads to the decrease of the CD4+/CD8+ ratio for an extensive period of time exceeding 12, even up to 24 months. In consequence, infections including opportunistic type, are frequently observed. We suggest, that in patients with CLL, 2-CdA should be used as second line treatment rather than the first line therapy until the final results of ongoing randomized clinical trials are available.     

Early results of a chemoimmunotherapy regimen of fludarabine, cyclophosphamide, and rituximab as initial therapy for chronic lymphocytic leukemia.

PURPOSE: Fludarabine and cyclophosphamide (FC), which are active in treatment of chronic lymphocytic leukemia (CLL), are synergistic with the monoclonal antibody rituximab in vitro in lymphoma cell lines. A chemoimmunotherapy program consisting of fludarabine, cyclophosphamide, and rituximab (FCR) was developed with the goal of increasing the complete remission (CR) rate in previously untreated CLL patients to >/= 50%. PATIENTS AND METHODS: We conducted a single-arm study of FCR as initial therapy in 224 patients with progressive or advanced CLL. Flow cytometry was used to measure residual disease. Results and safety were compared with a previous regimen using FC. RESULTS: The median age was 58 years; 75 patients (33%) had Rai stage III to IV disease. The CR rate was 70% (95% CI, 63% to 76%), the nodular partial remission rate was 10%, and the partial remission rate was 15%, for an overall response rate of 95% (95% CI, 92% to 98%). Two thirds of patients evaluated with flow cytometry had less than 1% CD5- and CD19-coexpressing cells in bone marrow after therapy. Grade 3 to 4 neutropenia occurred during 52% of courses; major and minor infections were seen in 2.6% and 10% of courses, respectively. One third of the 224 patients had >/= one episode of infection, and 10% had a fever of unknown origin. CONCLUSION: FCR produced a high CR rate in previously untreated CLL. Most patients had no detectable disease on flow cytometry at the end of therapy. Time to treatment failure analysis showed that 69% of patients were projected to be failure free at 4 years (95% CI, 57% to 81%).     

The role of nucleoside analogues in the treatment of chronic lymphocytic leukemia-lessons learned from prospective randomized trials

The newer purine nucleoside analogues (PNA), fludarabine (FAMP) and cladribine (2-chlorodeoxyadenosine, 2-CdA) have been synthesized recently and introduced into the treatment of chronic lymphocytic leukemia (CLL). The results of large phase II studies indicate that FAMP and 2-CdA are similarly active in CLL. Unfortunately, no prospective randomized study comparing the results of the treatment of CLL patients with FAMP and 2-CdA has been published so far. Significantly higher overall response (OR) and complete remission (CR) in patients treated initially with PNA than with chlorambucil or cyclophosphamide based combination regimens has been recently confirmed in five prospective multicentre randomized trials. These studies have also shown longer response duration in patients treated with PNA than with conventional chemotherapy. Overall survival progression free and events free survival were similar in patients treated with PNA and with chlorambucil or other alkylating agent based regimens. However, the majority of randomized trials were designed as cross over studies and most patients, treated with conventional chemotherapy were given PNA when refractory or in early relapse, which may influence the survival time. The results of a randomized study have shown a higher incidence of neutropenia and infections in patients treated with PNA than with chlorambucil. However. the frequency of autoimmune hemolytic anemia, pure red cell aplasia, secondary neoplasms and Richter's syndrome seems to be similar in patients treated with PNA and standard alkylating agents based chemotherapy. In conclusion, alkylating agents still have an important place in the routine management of the majority of CLL patients. They are in general safe, given on an out patients basis and significantly cheaper than PNA. PNA should be routinely used as second line treatment, and possibly as first line therapy in younger patients, who are candidates for potentially curative treatment such as stem cell transplantation and/or monoclonal antibodies.     

Chemoimmunotherapy with oral low-dose fludarabine,cyclophosphamide and rituximab (old-FCR) as treatment for elderly patients with chronic lymphocytic leukaemia

Median age at diagnosis for chronic lymphocytic leukaemia (CLL) patients is now 72 years, thus a consistent number of patients may not tolerate standard doses i.v. of fludarabine, cyclophosphamide and rituximab (FCR), the best available therapy, due to unacceptable myelotoxicity and risk of severe infections. We studied safety and efficacy of the addition of rituximab to the oral low-dose FC regimen (old-FCR) in a selected population of 30 elderly (median age 75, 15 untreated, 15 treated with 1 prior therapy) CLL patients. Complete remission (CR) rate was 80% in the untreated patients (overall response rate, ORR 93%), and 30% in pretreated patients (ORR 74%). Progression free survivals (PFS) were 45 months and 30 months in the untreated and treated patients, respectively. In patients achieving CR, old-FCR led to PFS of 67 months. Moreover, haematological toxicity was mild (grade 3–4: 15%) and patients were treated mostly in outpatient clinic. Old-FCR could be a good therapy option for elderly CLL patients outside clinical trials, larger studies are needed to confirm our findings.     

Fludarabine, cyclophosphamide, and rituximab for the treatment of patients with chronic lymphocytic leukemia or indolent non-Hodgkin lymphoma

BACKGROUND: The combination of fludarabine, cyclophosphamide, and rituximab (FC-R) shows significant in vitro synergism and may improve patient outcome with little overlapping toxicity. METHODS: Between December 2000 and June 2005, 77 patients completed therapy after a median of 4 cycles of FC-R (fludarabine at a dose of 25 mg/m2 intravenously [i.v.] on Days 1-3, cyclophosphamide at a dose of 250 mg/m2 i.v. on Days 1-3, and rituximab at a dose of 375 mg/m2 on Day 1). The median age of the patients was 59 years, 65% were male; 31% had previously untreated disease; and 44% had chronic lymphocytic leukemia (CLL), 29% had follicular lymphoma, and 27% other indolent lymphoid malignancies. In addition to standard disease response criteria, patients underwent evaluation using flow cytometric and/or molecular studies. RESULTS: Objective responses (OR) and complete responses (CR) were observed in 83% and 42%, respectively, of evaluable patients (n=76), respectively. For patients with CLL, the respective OR and CR rates were 100% and 67% as firstline therapy, and 95% and 14% as salvage therapy. For patients with follicular lymphoma, the respective OR and CR rates were 100% and 86% as firstline therapy, and 87% and 67% as salvage therapy. Responders who had no detectable disease on flow cytometric and/or molecular studies experienced prolonged remissions with no recurrences reported at a median 25 months of follow-up. Peripheral stem cell collection using stem cell factor plus granulocyte-colony-stimulating factor was successful in 10 of 13 patients who underwent mobilization (77%). CONCLUSIONS: FC-R is highly active as initial or salvage therapy in patients with CLL or indolent non-Hodgkin lymphoma. Collection of autologous stem cells during molecular remission is feasible and may facilitate future exploration of high-dose therapy in these patients.     

Comparison on therapeutic effects of RFT and RCTVP regimen in the treatment of patients with indolent B-cell lymphoma in China

To compare the efficacy and safety of RFT (retuximab, fludarabine, pirarubicin) with RCTVP (retuximab, cyclophophamide, pirarubicin, vindesine and prednisone) in 248 indolent B-cell non-Hodgkin's lymphoma (NHL) patients. Two hundred and forty-eight patients with indolent B-cell NHL were treated with combined chemotherapy, including RFT and RCTVP, from January 2002 to December 2010 in Tianjin Cancer Hospital. The rate of response, toxicity and long-term survival for the two regimens were analyzed retrospectively. For the previously untreated patients, overall response rate for RFT arm and RCTVP arm was 71.7 and 70.6%, and complete response rate was 47.5 and 54.9%, respectively (P?>?0.05). For the refractory and relapsed patients, overall response (OR) rate and complete response (CR) rate were significantly improved in the RFT arm versus the RCTVP arm (P?相似文献