The effect of subsequent therapies in patients with chronic lymphocytic leukemia previously treated with prednisone and either cladribine or chlorambucil.

We present the long-term follow-up and results of subsequent treatments in patients with chronic lymphocytic leukemia treated initially with cladribine + prednisone or chlorambucil + prednisone in a randomized, cross-over study. We found higher complete and overall responses rates in patients who received cladribine + prednisone as first and second-line treatment but no significant differences in survival.

Cladribine combined with cyclophosphamide is highly effective in the treatment of chronic lymphocytic leukemia.

The aim of the study was to evaluate the activity and toxicity of cladribine (2-CdA) in combination with cyclophosphamide (CY), the CC schedule, in patients with previously untreated B-cell chronic lymphocytic leukemia (B-CLL). From November 1998 to May 2002 82 patients with advanced or progressive B-CLL received treatment with 2-CdA at a dose of 0.12 mg/kg for three consecutive days and CY at a dose of 650 mg/m(2) on day 1. The cycles were repeated at four week intervals or longer if severe myelosuppression occurred. Guidelines for the evaluation of response and toxicity were those developed by the National Cancer Institute sponsored Working Group. Minimal residual disease (MRD) was detected by immunophenotyping only in patients with CR by standard criteria. In the analysed group an overall response (OR) rate (CR+PR) of 87.8% (95% CI 80.7-94.9%) was achieved, including complete response (CR) in 29.3% patients (95% CI 19.4-39.1%). Twenty-two of 24 patients with CR and 39 of 48 patients with PR are still in remission. Median duration of follow-up in these patients is 11.8 months (range 3-25.4). MRD was only detected in six out of 24 (25%) patients with CR. Grade III/IV thrombocytopenia was seen in four patients (4.9%) and neutropenia in 10 (12.2%). Severe infections were noted in 21 (25.6%) patients. Thirteen patients died, including seven with treatment related toxicity, one because of CLL progression and five because of reasons not related to CLL. In conclusion, the CC schedule is a highly active regimen in previously untreated B-CLL, with acceptable toxicity. The efficacy of the regimen seems to be higher than observed earlier after treatment with 2-CdA alone. A randomized clinical trial is in progress in our institutions.

Rituximab followed by cladribine in the treatment of heavily pretreated patients with indolent lymphoid malignancies.

The purpose of this study was to determine the efficacy and toxicity of combined therapy consisting of rituximab (RIT), an anti-CD20 monoclonal antibody, and cladribine (2-chlorodeoxyadenosine, 2-CdA) (RC regimen) in patients with refractory or relapsed indolent lymphoproliferative disorders. Twenty six CD20 antigen positive patients, 15 with B-cell chronic lymphocytic leukemia (B-CLL) and 11 with low grade non-Hodgin's lymphoma (LG-NHL) were enrolled to the study. Fourteen patients (53.8%) had refractory disease, the other 12 (46.2%) were recurrent after prior chemotherapy. RC regimen consisted of RIT at a dose of 375 mg/m2 in 6 h infusion on day 1 and 2-CdA at a dose of 0.12 mg/kg, in 2 h infusion, given on days 2-6. The RC courses were repeated at 4 week intervals or longer if severe myelosuppression occurred. Seventy eight cycles of RC with median of 3 cycles per patient were administered (range 1-5 cycles). Four patients (15.4%) (95% CI 1.5-29.3%), 1 with B-CLL and 3 with LG-NHL, achieved a complete response (CR). Fourteen patients (53,8%) (95%CI 34.6-72.9%), including 10 with B-CLL and 4 with LG-NHL, had a partial response (PR). Overall response rate (OR) was 69.2% (95%CI 51.4-86.9%) in the whole group, from 63.6% (95% CI 35.2 92.0%) in LG-NHL to 73.3% (95%CI 50.1-95.7%) in B-CLL patients. Twelve of 18 patients with CR/PR are still in remission, with the median follow up 10 (7-28 months). The median failure-free survival (FFS) of responders was 6.5 months. Hypersensitivity to RIT was the major toxicity of RC regimen, and occurred in 9 patients (34.6%), mostly only during the first infusion of RIT. Severe neutropenia (grade III) was seen in 3 patients (11.5%). Anemia and thrombocytopenia associated with RC treatment were observed in 5 (19.2%) and 2 patients (7.7%), respectively. Four episodes (15.4%) of grade III-IV infections were observed. There was no treatment related mortality. During the follow-up six patients (23.1%) died from the disease progression. In conclusion, the combination of RIT and 2-CdA is an effective and well tolerated treatment, even for heavily pre-treated patients, and the results seem to be better than in patients previously treated in our institution with 2-CdA alone. This regimen can be considered as an alternative treatment of CD-20 positive indolent lymphoproliferative disorders.

Cladribine in a weekly versus daily schedule for untreated active hairy cell leukemia: final report from the Polish Adult Leukemia Group (PALG) of a prospective, randomized, multicenter trial.

Cladribine (2-chlorodeoxyadenosine, 2-CdA) treatment-associated infections may shorten potentially long-term survival in hairy cell leukemia (HCL). In search of the optimal mode of 2-CdA administration, 132 patients with untreated HCL were randomized to receive either standard 5-day 2-CdA protocol or a novel schedule of 6 weekly 2-CdA infusions suggested to be less toxic. Analysis of treatment response confirmed similar complete remission rates, overall response rates, progression-free survival, and overall survival in both 2-CdA protocols. However, we did not observe lower toxicity in the weekly schedule. Of special interest, no significant differences were found in the rate of grade 3/4 infections (18% for daily and 26% for weekly protocol, difference -8.2%; 95% confidence interval [CI] -23.2% to 6.9%; P = .28) and the rate of septic deaths (3% for daily and 2% for weekly protocol, difference 1.4%; 95% CI -4.3% to 7.0%; P = .64). In conclusion, HCL treatment with weekly 2-CdA infusions is equally effective but no safer than the standard 5-day 2-CdA protocol.

Cladribine alone and in combination with cyclophosphamide or cyclophosphamide plus mitoxantrone in the treatment of progressive chronic lymphocytic leukemia: report of a prospective, multicenter, randomized trial of the Polish Adult Leukemia Group (PALG CLL2).

In this prospective randomized trial, we compared the efficacy and toxicity of cladribine (2-CdA) alone to 2-CdA combined with cyclophosphamide (CC) or cyclophosphamide and mitoxantrone (CMC) in untreated progressive chronic lymphocytic leukemia (CLL). Study end points were complete response (CR), overall response, minimal residual disease (MRD), progression-free survival, overall survival, and toxicity. From January 1, 1998 to December 31, 2003, 508 patients from 15 hematology departments were randomized. Compared with 2-CdA, CMC induced higher CR rate (36% vs 21%, P = .004), and a trend for higher CR rate with CC was observed (29% vs 21%, P = .08). Furthermore, the percentage of patients who were in CR and were MRD negative was higher in CMC compared with 2-CdA (23% vs 14%, P = .042). There were no differences in overall response, progression-free survival, and overall survival among treatment groups. Grade 3/4 neutropenia occurred more frequently in CC (32%) and CMC (38%) than in 2-CdA (20%) (P = .01 and P = .004, respectively). Infections were more frequent in CMC compared with 2-CdA (40% vs 27%, P = .02). In conclusion, CMC used in first-line treatment of CLL results in a higher CR rate and suppresses MRD more efficiently than 2-CdA monotherapy, although associates with increased toxicity. No important differences in efficacy and toxicity were found between CC and 2-CdA regimens.

Comparison of cladribine plus prednisone with chlorambucil plus prednisone in patients with chronic lymphocytic leukemia. Final report of the Polish Adult Leukemia Group (PALG CLL1).

BACKGROUND: We previously published an early report of a randomized, multicenter trial on the efficacy and toxicity of cladribine (2-CdA) + prednisone (P) compared with chlorambucil (Chl) + P in previously untreated patients with progressive or symptomatic chronic lymphocytic leukemia. Here we present the final report of this study. MATERIAL/METHODS: Of 229 patients, 126 received 2-CdA+P and 103 Chl+P. Patients with no response or progression after three courses or who relapsed earlier than 12 months after completing one treatment were switched to the other. Patients who relapsed later were retreated with the same schedule as before. RESULTS: Thirty-three patients were retreated with 2-CdA+P and 19 with Chl+P. Overall response (and complete response) rates were 35% (6%) and 47% (16%), respectively. In 50 patients initially treated with Chl+P and then with 2-CdA+P, complete response (CR) was achieved in 12 (24%) and overall response (OR) in 32 (64%). In 28 patients originally treated with 2-CdA+P and then with Chl+P, CR in 1 (3%, p=0.01) and OR in 6 (21%, p=0.003) were obtained. We found no statistically significant difference in overall survival time in patients treated initially with 2-CdA+P and Chl+P aged 60 years (4.63 and 5.27 years, respectively, p=0.45), 60-70 years (3.29 and 3.14 years, p=0.79), and >70 years (1.53 and 1.93 years, p=0.11). CONCLUSIONS: 2-CdA+P is significantly more effective as a second-line treatment and re-treatment than Chl+P. However, we found a trend to longer survival in elderly patients treated with Chl+P.

Re-treatment with cladribine-based regimens in relapsed patients with B-cell chronic lymphocytic leukemia. Efficacy and toxicity in comparison with previous treatment.

The aim of the study was to determine the effectiveness and toxicity of cladribine (2-CdA) used alone or in combination with prednisone (P) or cyclophosphamide and mitoxantrone in re-treatment of patients with progressive B-cell chronic lymphocytic leukemia (B-CLL). We analyzed treatment outcome in 40 patients who had responded to previous treatment with 2-CdA-based regimens. Criteria for re-treatment were the same as for the first treatment. The patients were retreated with the same agents if they responded to the first treatment and then relapsed with progressive disease not earlier than 3 months after achieving the first response. Eight patients received 2-CdA alone (0.12 mg kg(-1) d(-1)) i.v. for 5 d, and 21 patients additionally were given P (30 mg m(-2) d(-1)) orally, also for 5 d. Eleven patients received 2-CdA for 3 d combined with cyclophosphamide (650 mg m(-2)) i.v. and mitoxantrone (10 mg m(-2)) i.v. on day 1 (CMC regimen). The cycles were repeated usually at 4 wk intervals or longer if severe myelosuppression or infections occurred. The therapy was finished if complete remission (CR) was achieved or until maximum of six courses. Overall response (OR) in re-treatment was obtained in 16 out of 40 (40%) patients (95% CI 16-64), including 62% after 2-CdA, 33% after 2-CdA +P and 36% after CMC. CR was obtained in four (10%) patients. Residual disease evaluated in the patients with CR by surface immunophenotyping had been demonstrated in 5 out of 16 (31%) patients after the first treatment and in one out of four (25%) patients after re-treatment. The median progression-free survival (PFS) was 16 months (range 3-39) for the first treatment and 9.5 months (range 3-18) for re-treatment (P=0.34). Grade III or IV neutropenia was observed in 20% patients during the first treatment and in 35% patients during re-treatment (P=0.1). 2-CdA-induced thrombocytopenia occurred in 20% and 42% of the patients, respectively (P=0.05). Anemia was also more frequent during re-treatment (35%) than during the first treatment (7%) (P=0.007). Autoimmune hemolytic anemia developed in four (10%) of the patients during or after re-treatment. Severe infections, including pneumonia and herpes reactivation, occurred in 11 patients during the first treatment and in 10 patients during re-treatment. Twelve (30%) patients died during the study. Infections were the cause of death in six and AIHA in two patients. In conclusion, 2-CdA applied in monotherapy or in combination with prednisone or cyclophosphamide and mitoxantrone has therapeutic activity in some B-CLL patients in whom these drugs induced earlier complete or partial remission. However, since the second response is usually shorter and myelotoxicity more pronounced than during the first therapy, more clinical trials to find other therapeutical approaches are necessary.