[Efficacy and safety of intermediate-dose cytarabine in the treatment of children with refractory high risk Langerhans cell histiocytosis]

Objective: To analyze the efficacy, safety, and long-term prognosis of intermediate-dose cytarabine (Ara-c) regimen in the treatment of children with refractory risk organ involvement Langerhans cell histiocytosis (LCH). Methods: Clinical data of 17 children with multisystem and risk organ involvement LCH who failed the first-line therapy and were treated with intermediate-dose Ara-c (250 mg/m2, twice daily) regimen in the Hematology Center, Beijing Children's Hospital from January 2013 to December 2016 were analyzed retrospectively. In addition to the basic treatment of vindesine and dexamethasone, the patients received two regimens: regimen A: the intermediate-dose Ara-c combined with cladribine and regimen B: the intermediate-dose Ara-c alone. The efficacy, safety and prognosis of the two regimens were analyzed. Results: Among all 17 patients, there were 11 males and 6 females, with the diagnosis age of 2.1 (1.6, 2.7) years. Ten children received regimen A, all of them achieved active disease-better (AD-B) after 8 courses of induction therapy. The disease activity scores (DAS) decreased from 5.5 (3.0, 9.0) to 1.0 (0, 2.3). Seven children received regimen B, and 6 of them achieved AD-B after 8 courses of induction therapy. The DAS decreased from 4.0 (2.0, 4.0) to 1.0 (0, 2.0). The follow-up time was 6.2 (4.9,7.2) and 5.2 (3.7,5.8) years in group A and B. The 5-year overall survival rate was 100.0% in both groups, and the 5-year event free survival rate was (88.9±10.5)% and (85.7±13.2)% in group A and B. Grade 3 or 4 myelosuppression was observed in 8 patients in group A and 2 patients in group B. Conclusions: The intermediate-dose Ara-c regimen (with or without cladribine) is effective and safe for patients with refractory high-risk LCH, with a good long-term prognosis.

Improvements in quality of life over 2 years with cladribine tablets in people with relapsing multiple sclerosis: The CLARIFY-MS study

BACKGROUND

Multiple sclerosis (MS) negatively affects health-related quality of life (HRQoL).

OBJECTIVE

To evaluate HRQoL in people with highly active relapsing MS treated with cladribine tablets (CladT; 3.5 mg/kg cumulative dose over 2 years) in CLARIFY-MS.

METHODS

Changes in the MS quality of life (MSQoL)-54 scores were analysed using a repeated mixed-effects linear model. Subgroup analyses were performed for participants who were pretreatment-naïve and those pretreated with disease-modifying therapies (DMTs) before initiating CladT. Safety and tolerability of CladT were also assessed.

RESULTS

MSQoL-54 physical (mean change = 4.86; 95% confidence interval (CI) = 3.18, 6.53) and mental health (4.80; 95% CI = 3.13, 6.46) composite scores (primary endpoints) showed significant improvement at Month 24 versus Baseline (p < 0.0001). Changes in the MSQoL-54 scores were consistent across the pretreatment-naïve and DMT-pretreated subgroups. No new severe or opportunistic infections occurred. Most post-baseline lymphopenia events were Grade 1-2 in severity. Transient Grade-3 lymphopenia was observed in 19.7% (95/482) of participants. Grade-4 lymphopenia was not observed.

CONCLUSIONS

CladT treatment significantly improved the mean MSQoL-54 physical and mental health composite scores over 2 years. CladT efficacy in HRQoL, relapse rates and Expanded Disability Status Scale scores demonstrates its multidimensional effects in MS treatment.

Real-world treatment patterns and effectiveness of cladribine tablets in patients with relapsing forms of multiple sclerosis in the United States

BACKGROUND

Real-world evidence on the use of cladribine tablets (CladT) for relapsing forms of multiple sclerosis (RMS) in the United States is emerging. The objective of this study was to assess the real-world treatment patterns and effectiveness of CladT in RMS.

METHODS

Adults with RMS initiating CladT were selected from the Symphony Integrated Dataverse. Baseline and follow-up periods were the 12 months before and 24 months after CladT initiation (index date). Switching to another disease-modifying therapy (DMT) and number of CladT courses were described during follow-up. Annualized relapse rate (ARR), MS disease severity, Expanded Disability Status Scale-Derived Disability Indicators (EDSS-DDI), corticosteroid use, and healthcare resource utilization (HRU) were described during Years 1 and 2 of follow-up and compared with baseline.

RESULTS

A total of 539 CladT-treated patients were included (mean age: 49.9 years; 77.6 % female). Over the 2-year follow-up, 91 % and 59 % of patients had one and two CladT courses, respectively, and 7 % of patients had evidence of switching to another DMT. ARR, MS disease severity score, and corticosteroid use decreased significantly during follow-up compared with baseline, while EDSS-DDI remained stable. All-cause and MS-related HRU decreased during follow-up.

CONCLUSION

CladT-treated patients with RMS had low switch rates, reduced ARR, disease severity, corticosteroid use, and HRU.

Cladribine, Cytarabine, and Etoposide-Based Regimens Are Safe and Tolerable In Relapsed and Refractory Acute Myeloid Leukemia Patients

Intensive treatment regimens for relapsed/refractory (R/R) acute myeloid leukemia (AML) generally include an anthracycline, cytarabine, with or without a purine analog. In patients who cannot tolerate an anthracycline due to comorbidities, one may consider using etoposide. Given the ongoing fludarabine shortage, it has prompted the switch to other purine analogs, such as cladribine, in combination with cytarabine and etoposide in patients who may be eligible for intensive chemotherapy but not able to tolerate an anthracycline due to comorbidities or cardiotoxicity risks. Here, we present 4 patients who received a cladribine, cytarabine, and etoposide (CCE) based regimen for R/R AML. There were no significant therapy-related adverse events, dose holds, or delays. Two out of 3 evaluable patients were successfully bridged to allogeneic transplant, and one is pending another cycle of chemotherapy as a bridge to transplant. The CCE regimen offers a potential option for patients with R/R AML in need of an anthracycline-free salvage regimen during a fludarabine shortage.

Cladribine Effects on T and B Cells and T Cell Reactivity in Multiple Sclerosis

OBJECTIVE

Cladribine tablet therapy is an efficacious treatment for multiple sclerosis (MS), however, its mechanism of action on T and B cell subsets remains unclear. The purpose of this study was to investigate the treatment effects of cladribine on the peripheral pool of T and B cells subsets and reactivity toward central nervous system (CNS) antigens.

METHODS

In this cross-sectional exploratory study, frequencies and absolute counts of peripheral T and B cell subsets and B cell cytokine production from untreated patients with relapsing-remitting MS (RRMS) and patients treated with cladribine for 1 year were measured using flow cytometry. Autoreactivity was assessed using a FluoroSpot assay.

RESULTS

We found that 1 year after initiation of cladribine treatment, a lower number of CD4+ T cells was persisting whereas CD19+ B cell counts were normalized compared to untreated patients with RRMS. Follicular helper T cells and their effecter subsets producing cytokines exerting distinct B cell helper activity were lower and, additionally, the peripheral B cell pool was skewed toward a naïve and anti-inflammatory phenotype. Finally, reactivity to the recently identified CNS-enriched autoantigen RAS guanyl-releasing protein 2 (RASGRP2), but not to myelin basic protein and myelin oligodendrocyte glycoprotein, was lower in cladribine-treated patients.

INTERPRETATION

Together, these investigations on T and B cell subsets suggest that cladribine treatment impairs the B-T cell crosstalk and reduces their ability to mediate pathogenic effector functions. This may result in specific reduction of autoreactivity to RASGRP2 which is expressed in B cells and brain tissue. ANN NEUROL 2023;94:518-530.

Safety and efficacy of cladribine in multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Previously, several studies investigated the effect of cladribine among patients with multiple sclerosis (MS) as a treatment option. Due to the contradictory results of previous studies regarding the efficacy and safety of cladribine in the MS population, we aimed to conduct a systematic review and meta-analysis by including clinical trials and observational studies in terms of having more confirmative results to make a general decision.

METHODS

The three databases including PubMed, Scopus, and Web of Science were comprehensively searched in May 2022. We included the studies that investigated the efficacy and safety of cladribine in patients with MS. Eligible studies have to provide sufficient details on MS diagnosis and appropriate follow-up duration. We investigated the efficacy of cladribine with several outcomes including Expanded Disability Status Scale (EDSS) change, progression-free survival (PFS), relapse-free survival (RFS), and MRI-free activity survival (MFAS).

RESULTS

After two-step reviewing, 23 studies were included in our qualitative and quantitative synthesis. The pooled SMD for EDSS before and after treatment was - 0.54 (95%CI: - 1.46, 0.39). Our analysis showed that the PFS after cladribine use is 79% (95%CI 71%, 86%). Also, 58% of patients with MS who received cladribine remained relapse-free (95%CI 31%, 83%). Furthermore, the MFAS after treatment was 60% (95%CI 36%, 81%). Our analysis showed that infection is the most common adverse event after cladribine treatment with a pooled prevalence of 10% (95%CI 4%, 18%). Moreover, the pooled prevalence of infusion-related adverse events was 9% (95%CI 4%, 15%). Also, the malignancies after cladribine were present in 0.4% of patients (95%CI 0.25%, 0.75%).

CONCLUSION

Our results showed acceptable safety and efficacy for cladribine for the treatment of MS except in terms of reducing EDSS. Combination of our findings with the results of previous studies which compared cladribine to other disease-modifying therapies (DMTs), cladribine seems to be a safe and effective drug in achieving better treatment for relapsing-remitting MS (RRMS) patients.

Expert opinion on the long-term use of cladribine tablets for multiple sclerosis: Systematic literature review of real-world evidence

BACKGROUND

Treatment with cladribine tablets (CladT), an immune reconstitution therapy for relapsing multiple sclerosis (RMS), involves two short courses of treatment in Year 1 and Year 2. Most patients achieve sustained efficacy with CladT, but a small proportion may experience new disease activity (DA). Following completion of the indicated dose, physicians may have questions relating to the long-term management of these patients. Since the EU approval of CladT over 5 years ago, real-world evidence (RWE) is increasing and may provide some insights and guidance for clinical practice. We describe a systematic literature review (SLR) of RWE and provide expert opinions relating to six questions regarding the long-term use of CladT.

METHODS

Pertinent clinical questions were developed by a steering committee (SC) of 14 international multiple sclerosis (MS) experts regarding breakthrough DA in Year 1, new DA after 2 years or more of treatment, long-term management of stable patients, and whether additional courses of CladT may be required or safe. An SLR was performed in EMBASE and PubMed using the population, intervention, comparators, outcomes, study design (PICOS) framework to identify relevant studies within the last 15 years. Searches of key congress proceedings for the last 2-3 years were also performed. Following review of the results and RWE, the SC drafted and agreed on expert opinion statements for each question.

RESULTS

A total of 35 publications reporting RWE for CladT were included in this review. In the real world, breakthrough DA in Year 1 is of low incidence (1.1-21.9%) but can occur, particularly in patients switching from anti-lymphocyte trafficking agents. In most patients, this DA did not lead to treatment discontinuation. Reported rates of DA after the full therapeutic effect of CladT has been achieved (end of Year 2, 3 or 4) range from 12.0 to 18.7% in the few studies identified. No RWE was identified to support management decisions for stable patients in Year 5 or later. Views among the group were also diverse on this question and voting on expert opinion statements was required. Only two studies reported the administration of additional courses of CladT, but detailed safety outcomes were not provided.

CONCLUSIONS

RWE for the long-term use of CladT in the treatment of RMS is increasing, however, gaps in knowledge remain. Where possible, the RWE identified through the SLR informed expert statements, but, where RWE is still lacking, these were based solely on experiences and opinion, providing some guidance on topics and questions that occur in daily clinical practice. More real-world studies with longer-term follow-up periods are needed and highly anticipated.

Longitudinal humoral response in MS patients treated with cladribine tablets after receiving the second and third doses of SARS-CoV-2 mRNA vaccine

BACKGROUND

Multiple sclerosis (MS) patients receive immunomodulatory treatments which can influence their ability to maintain vaccine specific serological response overtime. MS patients treated with cladribine tablets developed a positive serology response following two doses of mRNA COVID-19 vaccine. However, there is only limited data regarding the effect of cladribine tablets on long-term humoral response after the second and the third booster.

METHODS

Serology response to SARS-CoV-2 was tested in healthy controls (HCs) and MS patients treated with cladribine tablets 6 and 9-12 months after the second dose, and 1 and 3-6 months following the third booster-dose of the BTN162b2 mRNA vaccine.

RESULTS

Thirty-five out of 36 MS patients treated with cladribine tablets and 100% (46/46) of HCs had a positive serology response up to 10 months after the second vaccine dose. In addition, all cladribine tablets -treated MS patients (22/22) and HCs (24/24) had a positive robust serology response following the third vaccine with a positive humoral response sustain up to 6 months. One month after the third vaccine dose IgG levels were significantly lower in patients treated with cladribine tablets compared to HCs (15,598+11,313 vs 26,394+11,335, p<0.01). Six-month post second vaccine and 3-6 months post third vaccine there was no difference in IgG levels between the groups (1088.0 ± 1072.0 vs 1153.0 ± 997.1, p = 0.79; 5234+4097 vs 11,198+14,679, p = 0.4).

CONCLUSION AND RELEVANCE

MS patients treated with cladribine tablets have sustained positive vaccine specific serology response following the second and third SARS-CoV-2 vaccine dose.

The CLARION study design and status update: a long-term, registry-based study evaluating adverse events of special interest in patients with relapsing multiple sclerosis newly started on cladribine tablets

OBJECTIVE

To describe the design of the CLARION post-approval safety study (EU PAS Register number, EUPAS24484) and provide a status update, including characteristics of patients included up to 1 May 2021.

METHODS

CLARION aims to further evaluate adverse events of special interest in patients who are newly initiating treatment with cladribine tablets for relapsing multiple sclerosis (MS). The study population consists of two cohorts: patients newly initiating cladribine tablets (cladribine cohort) and patients newly initiating oral fingolimod tablets (comparator fingolimod cohort), with an aim to include 8000 patients (4000 patients per cohort). The study relies on secondary use of data from pre-existing MS registries/data sources (except in Germany, where primary data collection is performed). The study is projected to last 15 years, with an anticipated 5-year inclusion period. Study outcomes are: malignancies; severe infections; tuberculosis; progressive multifocal leukoencephalopathy; other opportunistic infections; herpes zoster; severe lymphopenia (Grade ≥ 3); and treatment discontinuation.

RESULTS

As of 1 May 2021, 2393 patients were included in CLARION from seven participating MS registries/data sources (cladribine cohort, n = 1266; fingolimod cohort, n = 1127). The majority of patients are female (cladribine cohort, 72.5%; fingolimod cohort, 68.0%), with mean age at onset of MS of 31.5 years for the cladribine cohort and 30.9 years for the fingolimod cohort. The majority of patients in both cohorts had relapsing MS (cladribine cohort, 92.1%; fingolimod cohort, 93.5%).

CONCLUSION

By providing further information on adverse events of special interest during long-term follow-up, CLARION will assist neurologists and patients regarding treatment decision-making for management of relapsing MS.

[Recurrent and Refractory Langerhans Cell Histiocytosis in Children Treated with the Combination of Cladribine and Cytarabine]

OBJECTIVE

To observe the efficacy and prognosis of cladribine (2-CdA) combined with cytarabine (Ara-C) regimen in the treatment of relapsed refractory Langerhans cell histiocytosis (LCH) in children.

METHODS

Nine patients with relapsed refractory LCH treated with the 2-CdA combined with Ara-C regimen in the Department of Hematology and Oncology of Wuhan Children's Hospital from July 2014 to February 2020 were retrospectively analyzed, and the efficacy and disease status were evaluated according to the Histiocyte Society Evaluation and Treatment Guidelines (2009) and the Disease Activity Score (DAS), the drug toxicity were evaluated according to the World Health Organization（WHO） grading criteria for chemotherapy. All patients were followed up for survival status and disease-related sequelae.

RESULTS

Before the treatment combining 2-CdA and Ara-C, 7 of 9 patients were evaluated as active disease worse (ADW), and 2 as active disease stable (ADS) with a median disease activity score of 8 (4-15). Of 9 patients, 6 cases achieved non active disease (NAD) and 3 achieved active disease better (ADB) with a median disease activity score of 0 (0 to 5) after 2-6 courses of therapy. All 9 patients experienced WHO grade IV hematologic toxicity and 3 patients had hepatobiliary adverse effects (WHO grade I～II) after treatment. The median follow-up time was 31(1 to 50) months with all 9 patients survived, 3 of the 9 patients experienced sequelae to the disease with 2 combined liver cirrhosis as well as cholestatic hepatitis and 1 with oral desmopressin acetate tablets for diabetes insipidus.

CONCLUSION

2-CdA combined with Ara-C is an effective regimen for the treatment of recurrent refractory LCH in children, and the main adverse effect is hematologic toxicity, which is mostly tolerated in children. Early treatment with this regimen may be considered for patients with multisystem LCH with risky organ involvement who have failed first-line therapy and for patients with relapse.

Real-world evidence for cladribine tablets in multiple sclerosis: further insights into efficacy and safety

Cladribine (CLAD) is a purine nucleoside analog approved in tablet form to treat highly active multiple sclerosis (MS). CLAD tablets are the first oral therapy with an infrequent dosing schedule, administered in two annual treatment courses, each divided into two treatment cycles comprising 4–5 days of treatment. The efficacy and safety of CLAD tablets have been verified in randomized controlled clinical trials. Clinical observational studies are performed in more representative populations and over more extended periods, and thus provide valuable complementary insights. Here, we summarize the available evidence for CLAD tablets from post-marketing trials, including two observational, four long-term extensions, and two comparative studies. The patients in the post-marketing setting differed from the cohort recruited in the pivotal phase III trials regarding demographics and MS-related disability. The limited number of studies with small cohorts corroborate the disease-modifying capacity of oral CLAD and report on a durable benefit after active treatment periods. Skin-related adverse events were common in the studies focusing on safety aspects. In addition, single cases of CLAD-associated autoimmune events have been reported. Lastly, CLAD tablets appear safe regarding COVID-19 concerns, and patients mount a robust humoral immune response to SARS-CoV‑2 vaccination. We conclude that the current real-world evidence for CLAD tablets as immune reconstitution therapy for treatment of MS is based on a small number of studies and a population distinct from the cohorts randomized in the pivotal phase III trials. Further research should advance the understanding of long-term disease control after active treatment periods and the mitigation of adverse events.

Effect of SARS-CoV-2 mRNA vaccination in MS patients treated with disease modifying therapies

BACKGROUND

In patients with Multiple Sclerosis (pwMS) disease-modifying therapies (DMTs) affects immune response to antigens. Therefore, post-vaccination serological assessments are needed to evaluate the effect of the vaccine on SARS-CoV-2 antibody response.

METHODS

We designed a prospective multicenter cohort study enrolling pwMS who were scheduled for SARS-Cov-2 vaccination with mRNA vaccines (BNT162b2, Pfizer/BioNTech,Inc or mRNA-1273, Moderna Tx,Inc). A blood collection before the first vaccine dose and 4 weeks after the second dose was planned, with a centralized serological assessment (electrochemiluminescence immunoassay, ECLIA, Roche-Diagnostics). The log-transform of the antibody levels was analyzed by multivariable linear regression.

FINDINGS

780 pwMS (76% BNT162b2 and 24% mRNA-1273) had pre- and 4-week post-vaccination blood assessments. 87 (11·2%) were untreated, 154 (19·7%) on ocrelizumab, 25 (3·2%) on rituximab, 85 (10·9%) on fingolimod, 25 (3·2%) on cladribine and 404 (51·7%) on other DMTs. 677 patients (86·8%) had detectable post-vaccination SARS-CoV-2 antibodies. At multivariable analysis, the antibody levels of patients on ocrelizumab (201-fold decrease (95%CI=128-317), p < 0·001), fingolimod (26-fold decrease (95%CI=16-42), p < 0·001) and rituximab (20-fold decrease (95%CI=10-43), p < 0·001) were significantly reduced as compared to untreated patients. Vaccination with mRNA-1273 resulted in a systematically 3·25-fold higher antibody level (95%CI=2·46-4·27) than with the BNT162b2 vaccine (p < 0·001). The antibody levels on anti-CD20 therapies correlated to the time since last infusion, and rituximab had longer intervals (mean=386 days) than ocrelizumab patients (mean=129 days).

INTERPRETATION

In pwMS, anti-CD20 treatment and fingolimod led to a reduced humoral response to mRNA-based SARS-CoV-2 vaccines. As mRNA-1273 elicits 3·25-higher antibody levels than BNT162b2, this vaccine may be preferentially considered for patients under anti-CD20 treatment or fingolimod. Combining our data with those on the cellular immune response to vaccines, and including clinical follow-up, will contribute to better define the most appropriate SARS-CoV-2 vaccine strategies in the context of DMTs and MS.

FUNDING

FISM[2021/Special-Multi/001]; Italian Ministry of Health'Progetto Z844A 5 × 1000'.

Cost-effectiveness of cladribine tablets versus fingolimod in patients with highly active relapsing multiple sclerosis in Portugal

Aims: To assess the cost-utility of cladribine tablets versus fingolimod in patients with highly active relapsing-remitting multiple sclerosis (RRMS) in Portugal.Methods: A 1-year cycle cohort-based Markov state transition model was developed to simulate disease progression, measured by Kurtzke Expanded Disability Status Scale (EDSS), relapses, and conversion to secondary-progressive MS (SPMS). Patients were assumed to remain on treatment until progression to EDSS level 7, conversion to SPMS, or complete loss of efficacy due to waning effect. Natural history was based on British Columbia Multiple Sclerosis registry, London Ontario database, UK MS Trust, and cladribine tablets clinical trial (CLARITY). Portuguese all-cause mortality was adjusted for the MS associated increased mortality. Clinical inputs for active treatments (disability progression and relapse rate) were estimated on a network meta-analysis. Utility weights were derived from UK-MS Survey and published literature. Resource consumption by EDSS and due to relapses was based on published literature, National DRG microdata and expert opinion. Unit costs were obtained from official sources. The analysis was conducted from payers' perspective, time horizon of 50 years and discount rate of 5%, for both costs and benefits. Uncertainty was assessed via probabilistic and deterministic sensitivity analyses.Results: Compared to fingolimod, cladribine tablets were associated with a delay in progression, resulting in a gain of 0.85 quality adjusted life years (QALYs) and a cost decrease of 25,935 €. Probabilistic sensitivity analysis resulted in a mean ICER of -31,781 € per QALY and was dominant in 98.7% of the simulations. Cladribine tablets were dominant across the scenario analyses tested.Conclusions: Treatment of highly active RRMS with cladribine tablets was less costly and more effective than treatment with fingolimod. Hence, it is a dominant strategy in the Portuguese setting. No conclusions can be drawn from the present study regarding other treatment options, in particular natalizumab and alemtuzumab.

Severe skin reactions associated with cladribine in people with multiple sclerosis

OBJECTIVE

To report three cases of severe skin reactions in patients treated with cladribine for multiple sclerosis.

METHODS

Case study.

RESULTS

Patients developed severe rash 3-192 days after receiving cladribine. All were effectively treated with steroids and antihistamines. Additional doses of cladribine were administered after pretreatment with steroids and anti-histamines. One patient developed mild recurrence following re-exposure, which resolved within three days, whilst another patient tolerated re-exposure without further adverse reaction.

CONCLUSION

Severe skin reactions, well described in patients receiving cladribine for treatment of haematological conditions, may occur in patients treated with this compound for multiple sclerosis. Neurologists need to be aware of this rare, but significant adverse reaction. Re-exposure may be safe with standard pre-treatment against allergic reactions.

Impact of Nonrandomized Dropout on Treatment Switching Adjustment in the Relapsing-Remitting Multiple Sclerosis CLARITY Trial and the CLARITY Extension Study

OBJECTIVES

Statistical methods to adjust for treatment switching are commonly applied to randomized controlled trials (RCTs) in oncology. Nevertheless, RCTs with extension studies incorporating nonrandomized dropout require consideration of alternative adjustment methods. The current study used a recognized method and a novel method to adjust for treatment switching in relapsing-remitting multiple sclerosis (MS).

METHODS

The Cladribine Tablets Treating Multiple Sclerosis Orally (CLARITY) RCT evaluated the efficacy of cladribine versus placebo over 96 weeks. Many (but not all) CLARITY participants enrolled in the 96-week CLARITY extension study; placebo-treated patients from CLARITY received cladribine (PP→LL), and cladribine-treated patients were re-randomized to placebo (LL→PP) or continued cladribine (LL→LL). End points were time to first qualifying relapse (FQR) and time to 3-month and 6-month confirmed disability progression (3mCDP, 6mCDP). We aimed to estimate the effectiveness of the LL→PP treatment strategy compared with a counterfactual (unobserved) PP→PP strategy. We applied the commonly used rank-preserving structural failure time model (RPSFTM) and a novel approach that combined propensity score matching (PSM) with inverse probability of censoring weights (IPCW).

RESULTS

The RPSFTM resulted in LL→PP versus PP→PP hazard ratios (HRs) of 0.48 (95% confidence interval [CI] 0.36-0.62) for FQR, 0.62 (95% CI 0.46-0.84) for 3mCDP, and 0.62 (95% CI 0.44-0.88) for 6mCDP. The PSM+IPCW resulted in HRs of 0.47 (95% CI 0.38-0.63) for FQR, 0.61 (95% CI 0.43-0.86) for 3mCDP, and 0.63 (95% CI 0.40-0.87) for 6mCDP.

CONCLUSIONS

The PSM+IPCW HRs were consistent with those from the RPSFTM, suggesting that the results were not substantially biased by informative dropout, assuming that all relevant confounders were controlled for. There was no statistical evidence of a reduction in the cladribine treatment effect during the extension period.

Efficacy of common salvage chemotherapy regimens in patients with refractory or relapsed acute myeloid leukemia: A retrospective cohort study

To assess treatment response and overall survival (OS) in refractory or relapsed acute myeloid leukemia (R/R AML) patients treated by different common salvage chemotherapy regimens.Medical records data from 142 R/R AML patients were reviewed in this retrospective study. Patients were treated with regimens based on the following drugs: cytarabine, granulocyte colony-stimulating factor (G-CSF), and fludarabine (FLAG) (n = 46); cytarabine and G-CSF in addition to aclarubicin or daunorubicin (CAG/DAG) (n = 30); cytarabine, G-CSF, and cladribine (CLAG) (n = 27); cytarabine, etoposide, and mitoxantrone (MEA) (n = 17); cytarabine plus idarubicin, daunorubicin, or mitoxantrone (IA/DA/MA) (n = 12); and homoharringtonine, cytarabine, and aclarubicin or daunorubicin (HAA/HAD) (n = 10).A total of 43 (35.2%) patients achieved complete remission (CR), 60 (49.2%) patients achieved overall remission rate (ORR), and 18 (14.8%) patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CR. Median OS was 8.0 (95% CI 6.6-9.4) months with a 1-year OS rate of (29.9 ± 3.9)% and 3-year OS rate of (11.1 ± 3.6)%. No difference of CR (P = .621), ORR (P = .385), and allo-HSCT (P = .537) achievement was observed among different chemotherapy regimens. Interestingly, we observed that the CLAG-based regimen did not affect CR (P = .165), while it achieved a numerically higher ORR (P = .093) and was an independent factor for prolonged OS (P = .016). No other regimens were determined to be correlated with CR, ORR, or OS.FLAG-, CAG/DAG-, CLAG-, MEA-, IA/DA/MA- and HAA/HAD-based regimens were found to achieve similar CR rates, while the CLAG-based regimen achieved numerically higher ORR rates and significant favorable OS. Therefore, CLAG-based regimens should be a prioritized treatment option for R/R AML patients.

Systematic literature review and network meta-analysis of cladribine tablets versus alternative disease-modifying treatments for relapsing-remitting multiple sclerosis

OBJECTIVE

To assess the comparative efficacy and safety of cladribine tablets versus alternative disease modifying treatments (DMTs) in patients with active relapsing-remitting multiple sclerosis (RRMS), and in a subgroup with high disease activity (HRA + DAT), using systematic literature review (SLR) and network meta-analysis (NMA).

METHODS

MEDLINE, Embase, MEDLINE In-Process and CENTRAL databases were systematically searched to identify English-language publications of relevant studies of approved DMTs for RRMS. Searches were conducted from database inception to January 2017. Conference websites and trial registries were also searched. NMA considered the effects of DMTs on annualized relapse rate (ARR), confirmed disease progression (CDP), no evidence of disease activity (NEDA) and safety.

RESULTS

Of 10,825 articles retrieved and screened, 44 studies assessing 12 DMTs contributed to the NMA. In patients with active RRMS, cladribine tablets were associated with a significant 58% reduction in ARR versus placebo (p < .05); cladribine tablets were similar or significantly better than other DMT regimens and ranked fourth among DMTs, behind alemtuzumab, natalizumab and ocrelizumab. For CDP for 6 months and NEDA, improvements with cladribine tablets were significantly greater than those of placebo (p < .05), with no comparator DMT demonstrating significantly better results. Similar findings were reported in the HRA + DAT population. Overall adverse event risk for cladribine tablets did not differ significantly from that of placebo and most alternative DMTs.

CONCLUSION

In this first NMA to consider cladribine tablets, ocrelizumab and daclizumab for treatment of RRMS, cladribine tablets are a comparatively effective and safe alternative to other DMTs in both active RRMS and HRA + DAT populations.

Cladribine for multiple sclerosis

In the UK, there are twelve disease-modifying drugs licensed for various forms of multiple sclerosis (MS), of which three are oral therapies. An oral formulation of cladribine (Mavenclad - Merck Serono Europe Limited) was recently licensed by the European Medicines Agency (EMA) for the treatment of adult patients with highly active relapsing MS.^1,2 It is claimed to be "an innovatively simple approach" for treating this form of MS and "the only disease modifying therapy that can deliver and sustain 4 years of disease control with a maximum of 20 days oral treatment in the first 2 years."³ Here, we consider the evidence for its use in the treatment of highly active relapsing MS.

Treatment with disease-modifying drugs for people with a first clinical attack suggestive of multiple sclerosis

BACKGROUND

The treatment of multiple sclerosis has changed over the last 20 years. The advent of disease-modifying drugs in the mid-1990s heralded a period of rapid progress in the understanding and management of multiple sclerosis. With the support of magnetic resonance imaging early diagnosis is possible, enabling treatment initiation at the time of the first clinical attack. As most of the disease-modifying drugs are associated with adverse events, patients and clinicians need to weigh the benefit and safety of the various early treatment options before taking informed decisions.

OBJECTIVES

1. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for the treatment of a first clinical attack suggestive of MS compared either with placebo or no treatment;2. to assess the relative efficacy and safety of disease-modifying drugs according to their benefit and safety;3. to estimate the benefit and safety of disease-modifying drugs that have been evaluated in all studies (randomised or non-randomised) for treatment started after a first attack ('early treatment') compared with treatment started after a second attack or at another later time point ('delayed treatment').

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Group Trials Register, MEDLINE, Embase, CINAHL, LILACS, clinicaltrials.gov, the WHO trials registry, and US Food and Drug Administration (FDA) reports, and searched for unpublished studies (until December 2016).

SELECTION CRITERIA

We included randomised and observational studies that evaluated one or more drugs as monotherapy in adult participants with a first clinical attack suggestive of MS. We considered evidence on alemtuzumab, azathioprine, cladribine, daclizumab, dimethyl fumarate, fingolimod, glatiramer acetate, immunoglobulins, interferon beta-1b, interferon beta-1a (Rebif®, Avonex®), laquinimod, mitoxantrone, natalizumab, ocrelizumab, pegylated interferon beta-1a, rituximab and teriflunomide.

DATA COLLECTION AND ANALYSIS

Two teams of three authors each independently selected studies and extracted data. The primary outcomes were disability-worsening, relapses, occurrence of at least one serious adverse event (AE) and withdrawing from the study or discontinuing the drug because of AEs. Time to conversion to clinically definite MS (CDMS) defined by Poser diagnostic criteria, and probability to discontinue the treatment or dropout for any reason were recorded as secondary outcomes. We synthesized study data using random-effects meta-analyses and performed indirect comparisons between drugs. We calculated odds ratios (OR) and hazard ratios (HR) along with relative 95% confidence intervals (CI) for all outcomes. We estimated the absolute effects only for primary outcomes. We evaluated the credibility of the evidence using the GRADE system.

MAIN RESULTS

We included 10 randomised trials, eight open-label extension studies (OLEs) and four cohort studies published between 2010 and 2016. The overall risk of bias was high and the reporting of AEs was scarce. The quality of the evidence associated with the results ranges from low to very low. Early treatment versus placebo during the first 24 months' follow-upThere was a small, non-significant advantage of early treatment compared with placebo in disability-worsening (6.4% fewer (13.9 fewer to 3 more) participants with disability-worsening with interferon beta-1a (Rebif®) or teriflunomide) and in relapses (10% fewer (20.3 fewer to 2.8 more) participants with relapses with teriflunomide). Early treatment was associated with 1.6% fewer participants with at least one serious AE (3 fewer to 0.2 more). Participants on early treatment were on average 4.6% times (0.3 fewer to 15.4 more) more likely to withdraw from the study due to AEs. This result was mostly driven by studies on interferon beta 1-b, glatiramer acetate and cladribine that were associated with significantly more withdrawals for AEs. Early treatment decreased the hazard of conversion to CDMS (HR 0.53, 95% CI 0.47 to 0.60). Comparing active interventions during the first 24 months' follow-upIndirect comparison of interferon beta-1a (Rebif®) with teriflunomide did not show any difference on reducing disability-worsening (OR 0.84, 95% CI 0.43 to 1.66). We found no differences between the included drugs with respect to the hazard of conversion to CDMS. Interferon beta-1a (Rebif®) and teriflunomide were associated with fewer dropouts because of AEs compared with interferon beta-1b, cladribine and glatiramer acetate (ORs range between 0.03 and 0.29, with substantial uncertainty). Early versus delayed treatmentWe did not find evidence of differences between early and delayed treatments for disability-worsening at a maximum of five years' follow-up (3% fewer participants with early treatment (15 fewer to 11.1 more)). There was important variability across interventions; early treatment with interferon beta-1b considerably reduced the odds of participants with disability-worsening during three and five years' follow-up (OR 0.52, 95% CI 0.32 to 0.84 and OR 0.57, 95% CI 0.36 to 0.89). The early treatment group had 19.6% fewer participants with relapses (26.7 fewer to 12.7 fewer) compared to late treatment at a maximum of five years' follow-up and early treatment decreased the hazard of conversion to CDMS at any follow-up up to 10 years (i.e. over five years' follow-up HR 0.62, 95% CI 0.53 to 0.73). We did not draw any conclusions on long-term serious AEs or discontinuation due to AEs because of inadequacies in the available data both in the included OLEs and cohort studies.

AUTHORS' CONCLUSIONS

Very low-quality evidence suggests a small and uncertain benefit with early treatment compared with placebo in reducing disability-worsening and relapses. The advantage of early treatment compared with delayed on disability-worsening was heterogeneous depending on the actual drug used and based on very low-quality evidence. Low-quality evidence suggests that the chances of relapse are less with early treatment compared with delayed. Early treatment reduced the hazard of conversion to CDMS compared either with placebo, no treatment or delayed treatment, both in short- and long-term follow-up. Low-quality evidence suggests that early treatment is associated with fewer participants with at least one serious AE compared with placebo. Very low-quality evidence suggests that, compared with placebo, early treatment leads to more withdrawals or treatment discontinuation due to AEs. Difference between drugs on short-term benefit and safety was uncertain because few studies and only indirect comparisons were available. Long-term safety of early treatment is uncertain because of inadequately reported or unavailable data.

Role of Low-Dose 2-CdA in Refractory or Resistant Lymphoplasmocytic Lymphoma

Cladribrine (2-CdA), a purine analogue active on both dividing and resting lymphocytes, plays an important role in the treatment of indolent lymphoproliferative malignancies such as Hairy Cell Leukemia (HCL), Chronic Lymphocytic Leukemia (CLL), Lymphoplasmocytic Lymphoma (LPL), Waldenström's Macroglobulinemia (WM). With the aim of evaluating the efficacy and toxicity of low dose 2-CdA, 15 lymphoplasmocytic lymphoma patients, not eligible for more aggressive or standard therapies, because of age or poor performance status, were treated with the drug at a dose of 5 mg/m2, once a week for six total courses. All patients showed disease progression. Fourteen patients were valuable for response. In eleven out of these 14 (85.7%) disease progression stopped, with 21% having good hematological responses (one CR and two PR). The treatment was generally well tolerated, without serious infectious events. This schedule may be appropriate for the management of patients where the aim of the treatment is control of disease progression.

Systemic mastocytosis in adults: 2012 Update on diagnosis, risk stratification, and management

DISEASE OVERVIEW

Systemic mastocytosis (SM) results from a clonal proliferation of abnormal mast cells (MC) in one or more extra-cutaneous organs.

DIAGNOSIS

The major criterion is presence of multifocal clusters of morphologically abnormal MC in the bone marrow. Minor diagnostic criteria include elevated serum tryptase level, abnormal MC expression of CD25 and/or CD2, and presence of KITD816V.

RISK STRATIFICATION

The prognostic relevance of the 2008 World Health Organization (WHO) classification of SM has recently been confirmed. Classification of SM patients into indolent (SM), aggressive SM (ASM), SM associated with a clonal non-MC lineage disease (SM-AHNMD) and mast cell leukemia (MCL) subgroups is a useful first step in establishing prognosis.

MANAGEMENT

SM treatment is generally palliative. ISM patients have a normal life expectancy and receive symptom-directed therapy; infrequently, cytoreductive therapy may be indicated for refractory symptoms. ASM patients have disease-related organ dysfunction; interferon-α (±corticosteroids) can control dermatological, hematological, gastrointestinal, skeletal, and mediator-release symptoms, but is hampered by poor tolerability. Similarly, cladribine has broad therapeutic activity, with particular utility when rapid MC debulking is indicated; the main toxicity is myelosuppression. Imatinib has a therapeutic role in the presence of an imatinib-sensitive KIT mutation or in KITD816-unmutated patients. Treatment of SM-AHNMD is governed primarily by the non-MC neoplasm; hydroxyurea has modest utility in this setting.

INVESTIGATIONAL DRUGS

Dasatinib's in vitro anti-KITD816V activity has not translated into significant therapeutic activity in most SM patients. In contrast, preliminary data suggest that Midostaurin may produce significant decreases in MC burden in some patients.

A placebo-controlled trial of oral cladribine for relapsing multiple sclerosis

BACKGROUND

Cladribine provides immunomodulation through selective targeting of lymphocyte subtypes. We report the results of a 96-week phase 3 trial of a short-course oral tablet therapy in patients with relapsing-remitting multiple sclerosis.

METHODS

We randomly assigned 1326 patients in an approximate 1:1:1 ratio to receive one of two cumulative doses of cladribine tablets (either 3.5 mg or 5.25 mg per kilogram of body weight) or matching placebo, given in two or four short courses for the first 48 weeks, then in two short courses starting at week 48 and week 52 (for a total of 8 to 20 days per year). The primary end point was the rate of relapse at 96 weeks.

RESULTS

Among patients who received cladribine tablets (either 3.5 mg or 5.25 mg per kilogram), there was a significantly lower annualized rate of relapse than in the placebo group (0.14 and 0.15, respectively, vs. 0.33; P<0.001 for both comparisons), a higher relapse-free rate (79.7% and 78.9%, respectively, vs. 60.9%; P<0.001 for both comparisons), a lower risk of 3-month sustained progression of disability (hazard ratio for the 3.5-mg group, 0.67; 95% confidence interval [CI], 0.48 to 0.93; P=0.02; and hazard ratio for the 5.25-mg group, 0.69; 95% CI, 0.49 to 0.96; P=0.03), and significant reductions in the brain lesion count on magnetic resonance imaging (MRI) (P<0.001 for all comparisons). Adverse events that were more frequent in the cladribine groups included lymphocytopenia (21.6% in the 3.5-mg group and 31.5% in the 5.25-mg group, vs. 1.8%) and herpes zoster (8 patients and 12 patients, respectively, vs. no patients).

CONCLUSIONS

Treatment with cladribine tablets significantly reduced relapse rates, the risk of disability progression, and MRI measures of disease activity at 96 weeks. The benefits need to be weighed against the risks. (ClinicalTrials.gov number, NCT00213135.)

Acute Myeloid Leukemia Following Treatment with Cladribine for Hairy Cell Leukemia: A Case Report and Review of the Literature

The overall survival of patients with hairy cell leukemia (HCL) has significantly increased in recent years because of the development of effective treatments such as interferon alpha and purine analogs. Several reports have described an increased risk of secondary cancers, particularly solid tumors, in patients with HCL. We describe a case of a patient with HCL, who had prolonged pancytopenia after a single course of cladribine. Fifteen months after the diagnosis of HCL the patient developed acute myeloid leukemia (AML) and died shortly afterwards. Review of the literature shows few reports of acute leukemia in HCL patients. All of the 11 reported cases of leukemia in patients with HCL have been in patients who have been treated with either interferon alpha or purine analogs, and developed several years (mean 4.3 years; range 1.6-6.4 years) after the diagnosis of HCL. Our case is unusual in that the patient developed AML shortly (1.2 years) after the diagnosis and treatment of HCL. Further studies are needed to clarify whether leukemias seen in patients following the treatment of their HCL are incidental findings or related to HCL and its treatments.

Richter's Syndrome in the Brain First Manifested as an Ischaemic Stroke

Isolated central nervous system involvement in Richter's syndrome (RS) is extremely rare and only 6 such cases have been described, so far. We report a 60-year-old woman with B-cell chronic lymphocytic leukemia (B-CLL) heavily pretreated with cladribine based regimens and rituximab in whom RS in the brain was first manifested as a stroke. Initial cranial computed tomography (CT) revealed a hypodense area in the right parietal lobe showing no contrast enhancement. The follow-up CT done after 2 months showed an irregular, slightly hyperdense tumor surrounded by oedema with mass effect and midline shift. However, cerebrospinal fluid (CSF) examinations revealed no pathological changes. Neurosurgical operation was performed and the diagnosis of diffuse large B-cell lymphoma (DLBCL) has been established on the basis of histological and immunological investigation of the tumor. The pattern of immunoglobulin heavy chain (IgH) gene rearrangement in the patients' bone marrow aspirate and brain tumor was identical and suggested that both tumors originated from the same B-cell progenitors. The patient was then treated with brain irradiation (2000 cGy) and complete remission as assessed by MRI was achieved. Significant neurological improvement was observed and no clinical progression was stated 3 months after radiotherapy.

Multiple opportunistic infections after high-dose steroid therapy for giant cell arteritis in a patient previously treated with a purine analog

We present the case of a 74-y-old HIV-negative female who suffered simultaneously from multiple opportunistic infections and a Klebsiella pneumoniae sepsis during high-dose steroids for giant cell arteritis. The patient was treated with a purine analog due to hairy cell leukaemia 10 y previously. Purine analog therapy can lead to long lasting defects in cell-mediated immunity. In these patients, treatment with steroids should be closely monitored with CD4 counts.

Immune hemolytic anemia--selected topics

Autoimmune hemolytic anemia (AIHA) is most often idiopathic. However, in recent years, AIHA has been noted with increased incidence in patients receiving purine nucleoside analogues for hematologic malignancies; it has also been described as a complication of blood transfusion in patients who have also had alloimmunization. As the technology of hematopoietic stem cell transplantation has become more widespread, immune hemolysis in the recipients of ABO-mismatched products has become better recognized. The syndrome is caused by passenger lymphocytes transferred from the donor and, although transient, can be quite severe. A similar syndrome has been observed in recipients of solid organ transplants when there is ABO-incompatibility between donor and recipient. Venous thromboembolism is a little-recognized, though likely common, complication of AIHA, and may in some instances be related to coexistent antiphospholipid antibodies. While AIHA is a well-documented complication of malignant lymphoproliferative disorders, lymphoproliferative disorders may also paradoxically appear as a consequence of AIHA. A number of newer options are available for treatment of AIHA in patients refractory to corticosteroids and splenectomy. Newer immunosuppressives such as mycophenolate mofetil may have a role in such cases. Considerable experience has been accumulating in the last few years with monoclonal antibody therapy, mainly rituximab, in difficult AIHA cases; it appears to be a safe and effective option.

Analysis of outcome for patients with mass lesions of the central nervous system due to Langerhans cell histiocytosis treated with 2-chlorodeoxyadenosine

PURPOSE

To assess the activity and tolerability of 2-chlorodeoxyadenosine (2-CDA) in treating mass lesions of the central nervous system (CNS) due to Langerhans cell histiocytosis (LCH).

PATIENTS AND METHODS

The records of eight children and four adults with CNS LCH who were treated with 2-CDA were reviewed. The pattern of CNS disease included involvement of the hypothalamic-pituitary axis, gadolinium enhancing parenchymal as well as dural and choroid plexus based mass lesions, and atrophy. 2-CDA (5-13 mg/m(2)/day) was given on 3-5 consecutive days and repeated every 2-8 weeks for a period ranging from 3 to 12 months.

RESULTS

Eight patients demonstrated a complete radiographic response to 2-CDA with resolution of all enhancing mass lesions and four patients showed a sustained, partial radiographic response. One patient died from a non-treatment related cause without evidence of LCH on autopsy. With a follow-up ranging from 2 to 10 years after completion of therapy, the 11 surviving patients remain in continuous remission or are progression free. Prolonged bone marrow suppression was the most common toxicity (four patients). Permanent sequelae of CNS LCH, such as panhypopituitarism, diabetes insipidus (DI) and neurocognitive dysfunction, were not found to be reversible with 2-CDA therapy.

CONCLUSIONS

2-CDA is an active agent in patients with CNS LCH, with the possible exception of neurodegenerative disease, and should be further evaluated in a prospective multi-center clinical trial for LCH patients with enhancing mass lesions of the CNS.

Cladribine combined with cyclophosphamide and mitoxantrone is an active salvage therapy in advanced non-Hodgkin's lymphoma

The aim of this study was to determine the feasibility, efficacy and toxicity of the combined therapy consisting of cladribine (2-CdA), mitoxantrone and cyclophosphamide (CMC regimen) in patients with refractory or relapsed non-Hodgkin's lymphoma (NHL). Thirty six patients, 14 with mantle cell lymphoma (MCL), 10 with diffuse large B-cell lymphoma (DLBCL), 5 with follicular lymphoma (FL), 3 with small lymphocytic lymphoma (SLL), and 4 with T-cell lymphoma were enrolled to the study. The CMC protocol consisted of 2-CdA at a dose of 0.12 mg/kg in a 2-hour infusion on days 1 through 3, mitoxantrone 10 mg/m(2) i.v. on day 1 and cyclophosphamide 650 mg/m(2) i.v. on day 1. The CMC courses were repeated at intervals of 4 weeks. Thirty three patients were available for evaluation of response. Overall response rate (OR) was 58% (95% CI, 41--75%). Seven patients (21%; 95% CI, 7--35%) achieved a complete response (CR) and 12 patients (36%; 95% CI, 20--52%) achieved a partial response (PR). Seven of 19 patients with CR/PR are still in remission with a median follow-up of 3 months (range, 2-17 months). The median failure-free survival (FFS) was 5 months (range, 2-17 months). The median overall survival (OS) for the entire group was 9 months (range, 0.1-7 months). There was a significant difference in OS between responders and nonresponders after CMC therapy (log rank test, P = 0.015). When different disease status before CMC treatment was considered, a trend toward longer survival of recurrent patients was observed (log rank test, P = 0.08). Grade 3-4 neutropenia developed in 14 (39%) patients, and 16 episodes (15%) of grade 3-4 infections were observed. Grade 3-4 thrombocytopenia or anemia was seen in 9 patients (25%) and 10 patients (28%), respectively. The results of our study show that the CMC regimen is effective salvage therapy with acceptable toxicity in heavily pretreated patients with NHL including MCL and DLBCL.

Rituximab plus cladribine with or without cyclophosphamide in patients with relapsed or refractory chronic lymphocytic leukemia

OBJECTIVES

The aim of our study was to determine the feasibility, effectiveness and toxicity of combined regimens consisting of rituximab and cladribine (2-CdA) (RC) and RC plus cyclophosphamide (RCC) in the treatment of patients with recurrent or refractory chronic lymphocytic leukemia (CLL).

METHODS

The RC regimen consisted of rituximab given on day 1 and 2-CdA (days 2-6). The RCC protocol included rituximab (day 1), 2-CdA (days 2-4) and cyclophosphamide given on days 2-4. The courses were re-administered at time intervals of 4 weeks or longer if severe myelosuppression occurred.

RESULTS

Forty-six patients with CLL entered the study. Eighteen patients were treated with RC and 28 with RCC regimen. The median number of courses administered were three cycles (range 1-6). Three (6.5%) patients (95% CI: 1-14%) achieved a complete response and 31 (67%) patients (95% CI: 50-83%) a partial response. According to the particular regimen, the overall response rate was obtained in 12 (67%) patients treated with RC (95% CI: 45-89%) and in 22 patients (78%) treated with RCC (95% CI: 62-93%). The median progression free survival of responders to RC/RCC regimens was 12 months (range 4-46). Hypersensitivity to rituximab occurred in 16 (33%) patients, mostly during the first infusion of the drug. Grade 3/4 neutropenia was seen in six (13%) patients, grade 3/4 thrombocytopenia in three (9%) patients and grade 3/4 infections were observed in ten (28%) patients.

CONCLUSIONS

These data indicate that both RC and RCC regimens are feasible in heavily pretreated patients with CLL, showing also distinct therapeutic activity and relatively low toxicity, even in patients previously treated with cladribine-based protocols.

Prolonged follow-up after initial therapy with 2-chlorodeoxyadenosine in patients with indolent non-Hodgkin lymphoma: results of Cancer and Leukemia Group B Study 9153

BACKGROUND

The objective of this study was to determine the efficacy and toxicity of 2-chlorodeoxyadenosine (2-CdA) in patients with untreated, indolent non-Hodgkin lymphoma (NHL).

METHODS

For this multicenter, single-arm, Phase II study, 44 patients with treatment-naive, stage III or IV, indolent NHL (International Working Formulation subtypes A, B, and C) were enrolled. Patients received 0.14 mg/kg per day of 2-CdA as a 2-hour bolus infusion for 5 consecutive days every 28 days until maximal response or a total of 6 cycles.

RESULTS

Thirty-eight patients were eligible for response evaluation. The overall response rate was 100% (95% confidence interval [95% CI], 90.8-100%), and the complete response rate was 31.6% (95% CI, 17.5-48.7%). In the intent-to-treat population, the median failure-free survival was 2.0 years (95% CI, 1.3-3.4 years), and the overall survival rate was 7.0 years (95% CI, 4.3-9.4 years). Six patients had sustained remissions that lasted a median of 8.7 years (range, from 5.9 years to > or =11 years). Although 68% of patients experienced at least 1 grade 3 or 4 event, consisting primarily of myelosuppression, severe infections were rare, with only 8 grade 3 infections. Four late malignancies (prostate adenocarcinoma, ductal carcinoma in situ, and myelodysplasia) and 4 patients with large cell transformation were reported.

CONCLUSIONS

2-CdA is an active, well-tolerated therapy for patients with untreated, indolent NHL.

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.

The multicenter trial SAKK 37/95 of cladribine, cyclophosphamide and prednisone in the treatment of chronic lymphocytic leukemias and low-grade non-Hodgkin's lymphomas

A multicenter trial was performed to confirm the therapeutic efficacy and the toxicity profile of the combination of cladribine, cyclophosphamide and prednisone in low-grade non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Twenty-three adults with previously treated (61%) or untreated (39%) NHL International Working Formulation A or Binet B and C CLL were administered cladribine 0.1 mg/kg/day as a subcutaneous bolus for 5 days, intravenous cyclophosphamide 500 mg/m2 on day 1, and oral prednisone 40 mg/m2 on days 1-5, every 4 weeks. Unexpected early hematological toxicities led to dose modifications for pretreated patients who received cladribine for 3 days only up to a maximum of five courses. Responses were observed in 75%, with 7 patients obtaining a complete clinical and hematological response. Median duration of complete response was 9 months. Median time to progression or relapse was 31 months. Myelosuppression and infections were dose limiting whereas posttreatment complications, including fatalities, resulted from infections. Median overall survival time from trial entry was 60 months. Activity of the combination of cladribine, cyclophosphamide and prednisone was confirmed. However, in the specific setting of a multicenter trial, unexpected fatal infectious episodes occurred in pretreated patients. Great caution is thus required in these susceptible patients and the routine use of corticosteroids should probably be abandoned.

[Pulmonary cryptococcosis occurring 6 months after cladribine therapy for relapsed follicular lymphoma]

We report a case of follicular lymphoma in which pulmonary cryptococcosis occurred with cladribine therapy. The case involved a 72-year-old man. He was diagnosed as having follicular lymphoma, grade 1, clinical stage IVA from a tongue tumor biopsy in January 2003. A total of 6 courses of R-CHOP therapy was performed, but no clear effect was found. A new cervical lesion appeared, so he was treated with a total of 2 courses of R-EPOCH therapy, and the effect was classed as stable disease. We started cladribine therapy (0.09 mg/kg, seven days of continuous infusion) from February 2004, and complete remission was achieved after 4 courses of cladribine therapy. In January 2005, an abnormal nodular shadow in the right S10 area was found on chest CT images which was diagnosed as pulmonary cryptococcosis by serum antigen and a trans-bronchial lung biopsy. We started fluconazole (200 mg a day, initially intravenous drip infusion, followed by oral intake), following which both the pulmonary shadow and serum antigen improved. Afterward, the fifth course of cladribine therapy and local radiation therapy were performed against a relapse of lymphoma, but cryptococcosis did not reappear. The prolonged bone marrow suppression after cladribine therapy was considered to be a severe adverse event. These findings suggest that it is very important to pay attention to any opportunistic infection such as pulmonary cryptococcosis.

[Hypersensitivity reactions to multiple drugs during the course of hairy cell leukemia treated with 2-chlorodeoxyadenosine]

A 38-year-man developed diffuse erythema 3 days after the administration of 2-chlorodeoxyadenosine (cladribine or 2-CdA) and many other drugs for hairy cell leukemia (HCL). Patch-testing and scratch patch-testing showed positive reactions for clindamycin (10%, 30%) at 24 hours and 48 hours. Furthermore, provocation-testing showed positive reactions for sulfamethoxazole.trimethoprim, allopurinol, fluconazole, so our diagnosis was erythroderma-type drug eruption due to clindamycin, sulfamethoxazole-trimethoprim, allopurinol, fluconazole. Cutaneous side-effects associated with cladribine have seldom been described in cases of HCL. Our case suggests that there is a relationship between the drug hypersensitivity and the prolonged suppressed CD4 cell levels caused by cladribine.

Transformation and progression of Waldenström's macroglobulinemia following cladribine therapy in two cases: natural evolution or iatrogenic causation?

We report two cases of Waldenström's macroglobulinemia with an unusual aggressive transformation following treatment with cladribine (2-chlorodeoxyadenosine, 2-CdA), a purine analogue. The first patient developed transformation to a diffuse large-cell non-Hodgkin lymphoma, while the second developed extensive extramedullary involvement. Both patients displayed rapid progression following transformation and were refractory to chemotherapy. Both patients were pretreated with multiple courses of prednisone and chlorambucil, and transformation occurred shortly after therapy with cladribine. We propose that immune suppression from alkylating agents and purine analogues may have contributed to the unusual progression, resulting in a dismal outcome.

Early-onset autoimmune hemolytic anemia after cladribine therapy for Waldenström's macroglobulinemia

BACKGROUND

Purine nucleoside analogs are a class of antineoplastic drugs with potent lymphotoxicity against T and B lymphocytes, causing prolonged lymphopenia and linked to delayed immune complications such as opportunistic infections and more recently autoimmune hemolytic anemia (AIHA), seen mostly in patients with chronic lymphocytic leukemia (CLL). A characteristic temporal relation between fludarabine therapy and the appearance of a warm-reactive immunoglobulin G (IgG)-mediated AIHA in patients with CLL has been observed and, in some, the AIHA has been fatal. Whether both fludarabine and cladribine cause AIHA is uncertain because AIHA is commonly seen in patients with CLL without the use of these drugs. In contrast, AIHA is encountered in Waldenström's macroglobulinemia (WM) much less frequently, and the autoantibody is usually cold-reactive and IgM-mediated. In a few reported cases of AIHA arising in patients with WM after cladribine therapy, there was a latency of 24 to 60 months between therapy and the onset of AIHA, three of which were warm-reactive and IgG-mediated.

CASE REPORT

A warm-reacting IgG red cell autoantibody and evidence of hemolysis detected 1 month after completing cladribine therapy for WM, with warm antibody AIHA developing 4 months later, are described.

CONCLUSIONS

Cladribine, like fludarabine, is possibly able to produce this complication during or early after therapy. Because the use of purine analogs is becoming increasingly common, it is important to have an awareness of the complications that can arise during and after treatment. Further observations of warm AIHA during cladribine therapy are needed to establish it as a distinct complication.