Clinical assessment of Optivate®, a high-purity concentrate of factor VIII with von Willebrand factor, in the management of patients with haemophilia A

Summary.  Factor VIII (FVIII) concentrates have revolutionized the treatment of patients with haemophilia A. Concerns over the transmission of viral infections through these products have been addressed through stringent, donor‐screening procedures and robust antiviral manufacturing steps. Bio Products Laboratory has developed a high‐purity FVIII product with von Willebrand factor, Optivate^®. Its safety, tolerability and efficacy as prophylaxis and treatment of bleeds have been established in long‐term studies. Seventy previously treated patients with severe haemophilia A, with ≥20 exposure days, were recruited into two long‐term, multicentre, open‐label studies. The protocols were virtually identical. Patients received Optivate^® either prophylactically or on‐demand. A mean of 159.0 EDs were experienced over 11 320 infusions. Under both conditions, Optivate^® was well tolerated. Only 10% of patients experienced a treatment‐related adverse event; the most commonly reported were headache (4% of patients) and dizziness (3% of patients). The mean number of bleeds/patient over the 2 year treatment period was 23.5 during prophylactic use and 70.4 during on‐demand use. In patients treated prophylactically, clinical responses to breakthrough bleeds were rated by physicians as excellent or good and as very helpful or helpful by patients in 95% of bleeds. Clinical responses for on‐demand patients were rated as excellent or good by physicians and helpful or very helpful by the patients for 91% of bleeds. There were no viral transmissions or inhibitors. The studies confirm the clinical efficacy and safety of Optivate^® in both prophylactic and on‐demand management of patients with haemophilia A.

Thalidomide exerts distinct molecular antileukemic effects and combined thalidomide/fludarabine therapy is clinically effective in high-risk chronic lymphocytic leukemia

Thalidomide represents a promising immunomodulatory drug that targets both leukemia cells and the tumor microenvironment. We treated patients with chronic lymphocytic leukemia (CLL) with a combined thalidomide/fludarabine regimen and monitored cellular and molecular changes induced by thalidomide in vivo before fludarabine treatment. Thalidomide was given daily (100 mg p.o. per day) and fludarabine was administered on days 7-11 (25 mg/m(2) i.v. per day) within each 4-week cycle (maximum of 6 cycles). Twenty patients received thalidomide/fludarabine as first-line therapy and 20 patients were previously treated. Unmutated IgVH mutation status was found in 36 cases and 13 had high-risk cytogenetic aberrations (del17p, del11q). The overall response rate was 80 and 25% for untreated and previously treated patients, respectively. Although thalidomide reduced the number of CLL cells, the number of CD3 lymphocytes showed no significant change, but the number of CD4(+)CD25(hi)FOXP3(+) regulatory T cells (Tregs) was significantly decreased. Gene expression profiling revealed a thalidomide-induced signature containing both targets known to have a function in immunomodulatory drug action as well as novel candidate genes. Combined thalidomide/fludarabine therapy demonstrated efficacy in high-risk patients with CLL. Furthermore, our study provides novel biological insights into thalidomide effect, which might act by enhancing apoptosis of CLL cells and reducing Tregs, thereby enabling T-cell-dependent antitumor effect.

The influence of palifermin (Kepivance) on oral mucositis and acute graft versus host disease in patients with hematological diseases undergoing hematopoietic stem cell transplant

In this multicenter study, we assessed the use of palifermin (recombinant human-keratinocyte growth factor 1) in the prevention of oral mucositis (OM) and acute GvHD (aGvHD) induced by a hematopoietic stem cell transplant (HSCT). Fifty-three patients with hematological diseases received three doses of palifermin (60 mug/kg once daily i.v.) pre- and post-conditioning regimens (total six doses). A retrospective control group of 53 transplant patients received no palifermin. There was a significant reduction in the incidence of OM of WHO (World Health Organization) grades 1-4 (58 vs 94%, P<0.001), 3-4 (13 vs 43%, P<0.001) and the median duration of OM (4 vs 9 days, P<0.001) in the palifermin group compared to the control group. The incidence of analgesics (32 vs 75.5%, P<0.001), opioid analgesics (24 vs 64%, P<0.001) and total parenteral nutrition (11 vs 45%, P<0.001) was also significantly reduced. The analysis of distribution of affected organs revealed that aGvHD was less prevalent in the palifermin group (P=0.036). There was no significant difference in the onset of any OM after HSCT, time to engraftment and length of hospitalization between groups. The drug was generally well tolerated and safe. Our results suggest that the use of palifermin reduces OM and probably aGvHD after HSCT, but a randomized trial is needed.

Impact of prognostic factors on outcome in a phase III study comparing alemtuzumab to chlorambucil as first-line therapy for B-cell chronic lymphocytic leukemia (BCLL)

7035

Background: CAM307 is a phase III, open-label, randomized controlled trial comparing alemtuzumab (CAM) with chlorambucil (CHLO) for previously untreated B-CLL. Methods: The trial enrolled 297 previously untreated patients requiring therapy according to NCI-WG criteria. Patients were randomized 1:1 to CAM (n=149) vs CHLO (n=148) using standard dosing regimens. Diagnosis, Rai stage, response and disease progression were confirmed by an independent response review panel. In the overall study population, CAM demonstrated significantly higher overall response rates (ORR) than CHLO (83 % vs 55%) and a significant improvement in PFS (p= 0.0001) with manageable toxicities1. Outcomes according to Rai stage and cytogenetics have been previously reported.1,2 A pre-specified subgroup analysis of response rates (RR) and progression-free survival (PFS) by prognostic factors was performed. Results: Additional analyses revealed statistically significant PFS advantage in favor for CAM vs. CHLO for patients with β-2 microglobulin =3 mg/L (p<0.0001) or marrow infiltration =90% (p=0.0001). Conclusions: CAM is significantly superior to CHLO relative to overall and complete RR and PFS in the overall study population of previously untreated patients with CLL, and in patients < 65 years of age, < 70 years of age, maximum lymph node size < 5cm, and, performance status <2. Campath deserves further study in patients with age = 70, patients with massive lymphadenopathy, and in those with poor performance status. 1. Hillmen, P et al, Blood 108(11), abstract 301 2. Robak, T et al, Blood 108(11), abstract 2092

No significant financial relationships to disclose.

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Expression of RHAMM/CD168 and other tumor-associated antigens in patients with B-cell chronic lymphocytic leukemia

Antigen targeted immunotherapies might represent a novel treatment for B-cell chronic lymphocytic leukemia (B-CLL). We screened the mRNA expression of tumor-associated antigens (TAAs) from the literature (fibromodulin, survivin, OFA-iLRP, BAGE, G250, MAGE1, PRAME, proteinase, syntaxin, hTERT, WT-1) and TAAs defined previously by serological analysis of cDNA expression libraries from leukemic cells (PINCH, HSJ2, MAZ, MPP11, RHAMM/CD168, NY-Ren60). Peripheral blood mononuclear cells from 43 B-CLL patients and 20 healthy volunteers (HVs) were examined by conventional and quantitative RT-PCR. mRNA of RHAMM/CD168, fibromodulin, syntaxin and NY-Ren60 was expressed in 55-90%, and mRNA of HSJ2, MAZ and OFAiLRP was expressed in 90-100% of the patients. No expression of WT-1, hTERT, BAGE, G250, MAGE1 or survivin was observed. Low (2-20%) expression frequencies of MPP11, PINCH, PRAME and proteinase were detected. RHAMM/CD168, fibromodulin, PRAME and MPP11 showed expression in B-CLL patients, but not in HVs. Because of the exquisite tissue expression of RHAMM/CD168 and its high expression frequency in CLL patients, mixed lymphocyte peptide culture (MLPC), enzyme-linked immunosorbent spot (ELISPOT) and flow cytometry were performed for antigen specific T-cells. In MLPC, RHAMM specific responses by CD8+HLA-A2/R3tetramer+CCR7-CD45RAhigh effector T-cells were detected. RHAMM/CD168 might be a possible target for future immunotherapies in both ZAP-70(+) and ZAP-70(-) B-CLL patients.

Preliminary phase III efficacy and safety of alemtuzumab vs chlorambucil as front-line therapy for patients with progressive B-cell chronic lymphocytic leukemia (BCLL)

6511

Background: Phase 3, open-label, randomized comparative trial, enrolled Rai stage I-IV BCLL patients with previously untreated, progressive disease requiring treatment. Objectives: Compare efficacy and safety of alemtuzumab (CAMPATH [(CAM]) to chlorambucil (CHLO) as front-line therapy. Methods:Patients were randomized 1:1 to CAM 30 mg IV 3x/week for a maximum of 12 weeks (wks) or CHLO 40 mg/m2 PO once every 28 days, to a maximum of 12 cycles. All CAM patients received prophylactic antibiotic (trimethoprim/sulfamethoxazole DS) and antiviral (famciclovir) treatment during therapy and until CD4+ counts were ≥200 cells/μL. The primary endpoint was progression free survival; secondary endpoints included safety, response rate and overall survival. Results: Accrual completed in July 2004 with 297 patients enrolled (213 males, 84 females; median age 60 years); CAM n=149 and CHLO n=148. Treatment arms were balanced for key prognostic factors analyzed to date. Most patients had performance status 0–1 (96%) and maximum lymph nodes <5cm (70%). Median length of treatment with CAM = 11.7 wks, CHLO = 24.4 wks. The design provided for investigator assessment and an independent review of response (IRR). Preliminary data from the IRR are presented. Response rate for CHLO was consistent with historical data. Safety data indicate 34.7% of CAM patients and 19.7% of CHLO patients experienced a serious adverse event, with 21.1% and 4.1% considered drug related, respectively. The incidence of grade 3/4 thrombocytopenia and anemia were comparable in both treatment arms. Grade 3/4 neutropenia (42.2% vs 23.1%), infections (excluding CMV) (14.3% vs 6.8%), and CMV infections (6.8% vs 0%) were more frequent in the CAM arm. One treatment related death occurred in the CHLO arm. Conclusions: Preliminary efficacy and safety data confirm therapy naïve BCLL patients treated with single agent CAM have an excellent response rate with a manageable toxicity profile.

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Cytogenetic correlation with efficacy on alemtuzumab (CAM) vs chlorambucil (CHLO) as front-line therapy for patients with progressive B-cell chronic lymphocytic leukemia (BCLL)

6601

Background: CAM307, a phase III, open-label, randomized comparative trial, enrolled 297 Rai stage I-IV BCLL patients with previously untreated, progressive disease requiring treatment. Patients were randomized to treatment with CAM (n=149) vs. CHLO (n=148) using standard dosing regimens. Methods: Cytogenetic assessment was conducted prior to the start of protocol-specified therapy. Chromosomal aberrations were detected by fluorescence in situ hybridization (FISH) using specific probes. Molecular cytogenetic analyses by FISH included deletions (del) 6q21, 6q telomere, 11q22–23, 13q14–14.3 and 17p13; trisomy bands of 8q24 and 12p11.1-q11.1. Results: A total of 271 patients have been evaluated. Chromosomal aberrations were detected in 207 patients (76%) while 64 patients (24%) exhibited normal karyotype. Cytogenetic abnormalities were evaluated by response [overall response rate (ORR) and complete response (CR)] to each therapy based upon an independent response review. The comparisons of ORR and CR between treatment arms for each mutation type were calculated using the Exact method. Conclusions: Preliminarydata demonstrate a statistically significant superior response to CAM in patients with del 13q (ORR and CR) and del 11q (ORR) as well as a statistically significant superior CR to CAM in patients with normal cytogenetics. In addition, although the sample size is small, there is a trend towards a better ORR in patients with del 17p. Further exploration of CAM response rates relative to cytogenetic abnormality is warranted.

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An evaluation of factors predicting long-term response to thalidomide in 234 patients with relapsed or resistant multiple myeloma

The aim of this study was to assess the prognostic value of pretreatment clinical and laboratory parameters in refractory or relapsed multiple myeloma (MM) patients who have a long-term response to thalidomide (THAL), lasting at least 18 months. The study was carried out on 234 patients who received THAL for relapsed/refractory myeloma. Out of the 234 patients, 129 patients (55.1%) responded to THAL with a mean response duration of 11.9 months (ranging from 1 to 48) and an overall survival rate of 20.3 months (ranging 1–55 months). In 64 patients (27.4% of the whole group), the response to THAL lasted ⩾18 months with a mean response lasting 24 months. Statistical analysis of the group of nonresponders and patients with long-term response to THAL showed a significantly higher serum albumin level (P=0.0003) and haemoglobin level (P=0.05), as well as a lower β2 microglobulin (β2M) (P=0.022), LDH (P=0.045) serum level in patients with long-term response. In this study, the LDH and serum albumin level were predictors for response to THAL therapy. The β2M serum level was not a predictor for response to THAL. The albumin serum level was the best parameter distinguishing the group of patients with long-term response to THAL from the entire responding group (P=0.02).

The influence of thalidomide therapy on cytokine secretion, immunophenotype, BCL-2 expression and microvessel density in patients with resistant or relapsed multiple myeloma

Thalidomide (THAL) is currently used as a novel drug in patients with chemotherapy resistant or relapsed multiple myeloma. THAL antitumor activity seems to be very complex, however the precise mechanisms of its action are still not fully understood. The aim of this study was to assess some of possible mechanisms of THAL action both in in vivo analysis of immune cells phenotype and in in vitro cultures with THAL. The study involved 30 patients with relapsed or chemotherapy refractory multiple myeloma who were qualified to THAL treatment. We assessed immunophenotype of malignant plasma cells and T lymphocytes in both peripheral blood (PB) and bone marrow (BM) samples taken before and after 4 and 8 weeks of THAL treatment. Before therapy cytokine secretion (VEGF, HGF, bFGF, TNF, IL-6 an sIL-6R) and Bcl-2 expression in PB and BM cell cultures with THAL were analyzed. We used flow cytometry technique and ELISA method. The clinical response to therapy was assessed after 4 and 8 weeks of treatment. We also investigated microvessel density (MVD) in bone marrow samples before the THAL treatment and after 6 months of therapy in the group of responding patients. In cell cultures with THAL we detected statistically significant lowering of analyzed cytokines concentration and the decrease in Bcl-2 expression by malignant plasma cells in BM and CD8(+) T lymphocytes in BM and PB. In the group of patients responding to therapy we observed the decrease in the number of myeloma cells and significant increase of CD4(+) and CD8(+) cells in both PB and BM samples. There was statistically significant increase of CD3(+)/CD69(+) cells in the course of therapy, while the percentage of CD3+/HLA-DR(+) cells was significantly lower after 8 weeks of therapy. We also detected lowering of MVD after THAL therapy in responders group. The obtained results demonstrate that THAL efficacy in MM is multidirected and included such mechanisms like down-regulation of proangiogenic cytokines, that could lead to lowering of MVD, induction of apoptosis and influence on malignant cells and T lymphocytes immunophenotype.

Outcome and prognostic factors in advanced Hodgkin's disease treated with high-dose chemotherapy and autologous stem cell transplantation: a study of 341 patients

BACKGROUND

The reported probability of survival of patients with Hodgkin's disease (HD) following high-dose chemotherapy with autologous stem cell transplantation (HDC/ASCT) is 35-65% at 5 years. The Polish Lymphoma Research Group investigated retrospectively prognostic factors for overall survival (OS) and event-free survival (EFS), and the risk of secondary malignancies in a large series of patients who underwent HDC/ASCT.

PATIENTS AND METHODS

The data of 341 consecutive patients treated in 10 centers from 1990 to 2002 were collected and analyzed.

RESULTS

The actuarial 5-year OS and EFS were 64% [95% confidence interval (CI) 57% to 71%] and 45% (95% CI 39% to 51%), respectively. In the multivariate model, unfavorable prognostic factors for EFS were less than partial response at the time of ASCT [relative risk (RR), 2.92 (95% CI 1.68-5.08); P<0.001] and three or more previous chemotherapy lines (RR, 2.16; 95% CI 1.42-3.30; P<0.001). These two factors were also associated with unfavorable OS (RR, 3.32; 95% CI 1.90-5.79; P<0.001 and RR, 2.34, 95% CI 1.51-3.64; P<0.001). Five-year cumulative risk of secondary malignancy was 8.4% (95% CI 2% to 13%) and the only identified risk factor was splenectomy (P=0.02).

CONCLUSIONS

HDC/ASCT should be considered early in the course of disease for patients with a response after standard therapy.

Addition of cladribine to daunorubicin and cytarabine increases complete remission rate after a single course of induction treatment in acute myeloid leukemia. Multicenter, phase III study

To assess the efficacy of an original DAC-7 regimen: daunorubicine (DNR) 60 mg/m2/day, days 1-3; cytarabine (AraC) 200 mg/m2/day, days 1-7; cladribine (2-CdA) 5 mg/m2/day, days 1-5, 400 untreated adult acute myeloid leukemia patients (including 63 with preceding myelodysplastic syndrome), aged 45 (16-60) years were randomized to either DAC-7 (n=200) or DA-7 (without 2-CdA, n=200). The overall CR rate equaled 72% for DAC-7 and 69% for DA-7 arm (P=NS). After a single course of DAC-7 induction, the CR rate equaled 64% and was significantly higher compared to 47% in the DA-7 arm (P=0.0009). Median hospitalization time during the induction was 7 days shorter for DAC-7 compared to the DA-7 group (33 vs 40 days, P=0.002). Toxicity was comparable in both groups. The probability of 3-year leukemia-free survival (LFS) for DAC-7 and DA-7 group equaled 43 and 34%, respectively (P=NS). There was a trend toward higher LFS rate for patients aged >40 years receiving DAC-7 compared with DA-7 regimen (44 vs 28%, P=0.05). This study proves that addition of 2-CdA increases antileukemic potency of DNR+AraC regimen, thus resulting in a higher CR rate after one induction cycle when compared to DA-7, without additional toxicity. It shortens hospitalization time and may improve long-term survival in patients aged >40 years.

The treatment of acute myeloid leukemia with mitoxantrone, etoposide and low-dose cytarabine in elderly patients - a report of Polish Acute Leukemia Group (PALG) phase II study

The common dilemma in the treatment of elderly patients with acute myeloid leukemia (AML) is whether to use intensive myelosuppresive therapy with higher risk of treatment related mortality (TRM), but a chance for complete remission (CR), or to treat less intensively in order to prolong survival time with a better quality of life. The aim of this prospective, phase II study was to assess the efficacy and toxicity of low dose combination induction treatment consisted of cytarabine at a dose of 10 mg/m2 every 12 h s.c. for 7 days, VP-16 at a dose of 100 mg/day p.o. for 7 days and mitoxantrone at a dose of 6 mg/m2 i.v daily on days 1-3. Two induction courses were planned. In the group of 44 patients 12 (27%) achieved CR, 4 (9%) patients were in PR and there were 9 (20%) early deaths (ED). Age, performance status, preceding myelodysplastic syndrome, karyotype, WBC and % of blasts in bone marrow were not significant prognostic factors for CR probability. The following initial factors appeared to be related to a shorter duration of survival time from the start of treatment: age >70 (p<0.03), poor performance status (p<0.03), and % of BM blasts 50 (p<0.05). We conclude that, despite promising results in the pilot study the efficacy of this induction treatment is not better than the efficacy of other regimens. The hematological toxicity of this treatment seems to be comparable with "3+7" regimen.

Thalidomide treatment of resistant or relapsed multiple myeloma patients

BACKGROUND AND OBJECTIVES

Thalidomide is currently used as a very promising drug in patients with recurrent multiple myeloma or those refractory to chemotherapy. Literature data show prolonged survival in patients with advanced multiple myeloma treated with thalidomide but the optimal time and dose of thalidomide treatment remain to be established.

DESIGN AND METHODS

We have treated 53 refractory or relapsed myeloma patients with thalidomide (Grunenthal, Aachen). The patients received thalidomide orally as monotherapy at a starting dose of 200 mg daily, with a dose increase of 100 mg every week to a maximum well-tolerated dose of 400 mg. All the patients qualified for the therapy underwent clinical and laboratory assessments every 4 weeks. Laboratory tests included complete blood count, electrophoresis, immunoglobulin level, lactate dehydrogenase (LDH), C-reactive protein, b2 microglobulin concentration, liver and renal function tests and there was also a monthly neurological examination. Bone marrow aspiration was performed every 3 months during the 12-month treatment.

RESULTS

Among 53 evaluable patients, a clinical response was observed in 27 (51%): there was a major response in 7 patients, a partial response in 12 and a minor response in 8.

INTERPRETATION AND CONCLUSIONS

In responding patients the earliest response was observed after 4 weeks of treatment and the latest after 12 weeks of treatment. Our results, obtained during a long observation period, show that thalidomide is an effective drug, with an acceptable degree of toxicity, in patients with refractory multiple myeloma.

Assessment of Apoptosis Regulating Factors BCL-2 and Fas Antigens on Malignant and Normal Plasma Cells

Multiple myeloma (MM) is characterised by slow proliferation of malignant plasma cells and their accumulation within the bone marrow. The dysregulation of programmed cell death (apoptosis) is a very important mechanism in the pathogenesis of this tumour. It prompted us to investigate the apoptosis regulating factors such as the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 on bone marrow malignant plasma cells in untreated patients with newly diagnosed MM and to compare them with their normal counterparts-plasma cells isolated from bone marrow of healthy individuals. Twenty-nine MM patients and 16 healthy persons were studied. Bone marrow mononuclear cells were isolated, indicated by monoclonal antibodies and analysed using the flow cytometry method. There was no statistically significant difference in BCL-2 expression in plasma cells between patients and control groups. However the percentage of BCL-2 positive cells was significantly related to the clinical stage of the disease. We detected statistically significant lower percentage of Fas positive cells in the patient group than in control. We concluded that in MM at diagnosis the expression of BCL-2 in bone marrow malignant plasma cells was comparable to normal plasma cells but expression of Fas antigen on these cells was lower. It suggests that down regulation of Fas and normal regulation of BCL-2 may be implicated for myeloma cell survival and their escape from apoptosis in vivo.

Short Communication: Expression of Apoptosis Regulating Factors on T Lymphocytes in Multiple Myeloma Patients

Multiple myeloma (MM) is a malignant proliferation of plasma cells in which dysregulation of programmed cell death (apoptosis) is responsible for tumor cell expansion. However some phenotypic and functional alterations of T cells in MM patients have been reported, that also can influence the plasma cell growth. The aim of the study was to assess some aspects of T lymphocyte apoptosis in MM to obtain a better understanding of the changes in the immune system in this disease. Flow cytometry was used to analyze the expression of two main regulators of apoptosis: the pro-apoptotic Fas antigen and the anti-apoptotic protein BCL-2 in patients with untreated MM and in healthy controls. ELISA was used to determine soluble Fas ligand (sFasL) serum levels in patients and control groups. We detected statistically significant higher Fas expression in patients than in controls both on CD4 and CD8 lymphocytes, but no differences in BCL-2 expression by these cells. The sFasL level was statistically significant lower in patients than in controls. Our results indicate that T cells in MM are controlled by up-regulation of Fas. The Fas/FasL system induces the killing of T cells expressing Fas antigen, what could account for the incapability of the immune system to protect host against tumor expansion.

Flow cytometric analysis in diagnosis of thymoma metastases

Thymomas are relatively rare tumours of the anterior mediastinum, constituting approximately 10-15% of all mediastinal tumours. In contrast to other neoplasms, they rarely present distant metastases. We describe a case of thymoma with long survival and skin metastases diagnosed by two-colour flow cytometry.

Intermittent 2-hour intravenous infusions of 2-chlorodeoxyadenosine in the treatment of 110 patients with refractory or previously untreated B-cell chronic lymphocytic leukemia

The purpose of our study was to determine the effectiveness of 2-CdA in 2-hour intravenous infusions in the treatment of B-CLL. One hundred and ten patients with B-CLL received 1 to 10 courses of 2-CdA (median 2.5) at a dosage of 0.12 mg/kg daily for 5 consecutive days. Eighteen of them were untreated and 92 relapsed or became refractory to previous therapeutic modalities. Complete remission (CR) was achieved in 8 (7.3%) and partial remission (PR) in 35 patients (31.8%) giving an overall response rate of 39.1%. In 3 patients, cross-resistance to fludarabine was noticed. Toxic effects of 2-CdA were more frequently observed in previously treated patients. Hemorrhagic complications due to drug-induced thrombocytopenia were noticed in 25 (22.7%) and severe infections including sepsis in 14 (12.7%) patients.

2-Chlorodeoxyadenosine treatment in non-Hodgkin's lymphoma and B-cell chronic lymphocytic leukemia resistant to conventional chemotherapy: results of a multicentric experience. International Society for Chemo-Immunotherapy

Among the purine analogs, 2-chlorodeoxyadenosine (2-CDA) is particularly effective for the treatment of hairy cell leukemia and Waldemstrom's macroglobulinemia. Both efficacy and toxicity of 2-CDA were evaluated in previously treated patients affected with chronic lymphoproliferative disorders such as low-grade non-Hodgkin's lymphoma (NHL) and B-cell chronic lymphocytic leukemia (CLL). Thirty cases, mainly refractory, 16 affected with CLL, were included from six centers of the International Society for Chemo-Immunotherapy (IGCI). 2-CDA was administered in a 2 h i.v. infusion for 5-7 days at the standard dose of 0.1 mg/kg/day every 4 weeks. The median number of cycles was 3. Of 30 cases, eight (26.7%) achieved a complete remission (CR), nine (30%) a partial remission (PR), and two (6.7%) a minor response, while five cases (16.6%) did not respond, and six (20%) were considered early deaths. The overall response rate (CR + PR) was 56.7%, with a median response duration of 12 months (range 3-28 +) and a better response in CLL patients. Considering that the majority of patients were heavily pretreated, toxicity was acceptable, with 40% of cases not presenting any toxic effect. The main toxicity consisted in infectious complications. Based on the results of the present study, we confirm that 2-CDA is an effective drug in these lymphoproliferative disorders, suggesting its possible use either alone or in combination, also as first-line therapy.