Elly Barry

Assessment of dexrazoxane as a cardioprotectant in doxorubicin-treated children with high-risk acute lymphoblastic leukaemia: long-term follow-up of a prospective, randomised, multicentre trial

BACKGROUND Doxorubicin chemotherapy is associated with cardiomyopathy. Dexrazoxane reduces cardiac damage during treatment with doxorubicin in children with acute lymphoblastic leukaemia (ALL). We aimed to establish the long-term effect of dexrazoxane on the subclinical state of cardiac health in survivors of childhood high-risk ALL 5 years after completion of doxorubicin treatment. METHODS Between January, 1996, and September, 2000, children with high-risk ALL were enrolled from nine centres in the USA, Canada, and Puerto Rico. Patients were assigned by block randomisation to receive ten doses of 30 mg/m² doxorubicin alone or the same dose of doxorubicin preceded by 300 mg/m² dexrazoxane. Treatment assignment was obtained through a telephone call to a centralised registrar to conceal allocation. Investigators were masked to treatment assignment but treating physicians and patients were not; however, investigators, physicians, and patients were masked to study serum cardiac troponin-T concentrations and echocardiographic measurements. The primary endpoints were late left ventricular structure and function abnormalities as assessed by echocardiography; analyses were done including all patients with data available after treatment completion. This trial has been completed and is registered with ClinicalTrials.gov, number NCT00165087. FINDINGS 100 children were assigned to doxorubicin (66 analysed) and 105 to doxorubicin plus dexrazoxane (68 analysed). 5 years after the completion of doxorubicin chemotherapy, mean left ventricular fractional shortening and end-systolic dimension Z scores were significantly worse than normal for children who received doxorubicin alone (left ventricular fractional shortening: -0·82, 95% CI -1·31 to -0·33; end-systolic dimension: 0·57, 0·21-0·93) but not for those who also received dexrazoxane (-0·41, -0·88 to 0·06; 0·15, -0·20 to 0·51). The protective effect of dexrazoxane, relative to doxorubicin alone, on left ventricular wall thickness (difference between groups: 0·47, 0·46-0·48) and thickness-to-dimension ratio (0·66, 0·64-0·68) were the only statistically significant characteristics at 5 years. Subgroup analysis showed dexrazoxane protection (p=0·04) for left ventricular fractional shortening at 5 years in girls (1·17, 0·24-2·11), but not in boys (-0·10, -0·87 to 0·68). Similarly, subgroup analysis showed dexrazoxane protection (p=0·046) for the left ventricular thickness-to-dimension ratio at 5 years in girls (1·15, 0·44-1·85), but not in boys (0·19, -0·42 to 0·81). With a median follow-up for recurrence and death of 8·7 years (range 1·3-12·1), event-free survival was 77% (95% CI 67-84) for children in the doxorubicin-alone group, and 76% (67-84) for children in the doxorubicin plus dexrazoxane group (p=0·99). INTERPRETATION Dexrazoxane provides long-term cardioprotection without compromising oncological efficacy in doxorubicin-treated children with high-risk ALL. Dexrazoxane exerts greater long-term cardioprotective effects in girls than in boys. FUNDING US National Institutes of Health, Childrens Cardiomyopathy Foundation, University of Miami Womens Cancer Association, Lance Armstrong Foundation, Roche Diagnostics, Pfizer, and Novartis.

Anthracycline-induced cardiotoxicity: course, pathophysiology, prevention and management

Although effective anti-neoplastic agents, anthracyclines are limited by their well recognized and pervasive cardiotoxic effects. The incidence of late progressive cardiovascular disease in long-term survivors of cancer is established and may contribute to heart failure and death. To maximize the benefits of these drugs, a high-risk population has been identified and new strategies have been investigated to minimize toxic effects, including limiting the cumulative dose, controlling the rate of administration and using liposomal preparations and novel anthracycline analogues. Dexrazoxane also shows promise as a cardioprotectant during treatment. This paper reviews these strategies, as well as medications used to manage anthracycline-induced cardiotoxicity, and functional and biochemical means of monitoring cardiotoxicity, including echocardiography, radionuclide scans and biomarker analysis. The treatment of adult cancer survivors who have had anthracycline-related cardiotoxicity has not been systematically studied. Empirically, anthracycline-associated cardiac dysfunction is treated very similarly to other forms of heart failure. These treatments include avoiding additional cardiotoxic regimens, controlling hypertension, lifestyle changes, medications and heart transplantation.

Favorable Outcome for Adolescents With Acute Lymphoblastic Leukemia Treated on Dana-Farber Cancer Institute Acute Lymphoblastic Leukemia Consortium Protocols

PURPOSE Historically, adolescents with acute lymphoblastic leukemia (ALL) have had inferior outcomes when compared with younger children. We report the outcome of adolescents treated on Dana-Farber Cancer Institute (DFCI; Boston, MA) ALL Consortium Protocols conducted between 1991 and 2000. PATIENTS AND METHODS A total of 844 patients aged 1 to 18 years, with newly diagnosed ALL were enrolled onto two consecutive DFCI-ALL Consortium Protocols. We compared outcomes in three age groups: children aged 1 to 10 years (n = 685), young adolescents aged 10 to 15 years (n = 108), and older adolescents aged 15 to 18 years (n = 51). RESULTS With a median follow-up of 6.5 years, the 5-year event-free survival (EFS) for those aged 1 to 10 years was 85% (SE, 1%), compared with 77% (SE, 4%) for those aged 10 to 15 years, and 78% (SE, 6%) for those aged 15 to 18 years (P = .09). Adolescents were more likely to present with T-cell phenotype (P < .001) and less likely to have the TEL-AML1 fusion (P = .05). The incidence of pancreatitis and thromboembolic complications, but not asparaginase allergy, was higher in patients 10 years of age compared with those younger than 10 years. However, there was no difference in the rate of treatment-related complications between the 10- to 15-year and 15- to 18-year age groups. CONCLUSION Adolescents were more likely to present at diagnosis with biologically higher risk disease (T-cell phenotype and absence of the TEL-AML1 fusion) and more likely to experience treatment-related complications than younger children. However, the 5-year EFS for older adolescents was 78% +/- 6%, which is superior to published outcomes for similarly aged patients treated with other pediatric and adult ALL regimens. Based on this experience, we currently are piloting our regimen in patients aged 18 to 50 years.

Absence of Secondary Malignant Neoplasms in Children With High-Risk Acute Lymphoblastic Leukemia Treated With Dexrazoxane

PURPOSE Dexrazoxane is a drug used to prevent anthracycline-induced cardiotoxicity. A recent report found an association between the use of dexrazoxane and the risk of developing secondary malignant neoplasms (SMNs) in children with Hodgkins disease. We report the absence of an association of SMNs in children with acute lymphoblastic leukemia (ALL) treated on Dana-Farber Cancer Institute ALL Consortium Protocol 95-01. PATIENTS AND METHODS Two hundred five children with high-risk (HR) ALL were randomly assigned to receive doxorubicin alone (n = 100) or doxorubicin with dexrazoxane (n = 105) during the induction and intensification phases of multiagent chemotherapy. We compared incidence of SMNs in these two groups. RESULTS With a median follow-up of 6.2 years, no differences in the incidence of SMNs were noted between the group that received dexrazoxane and the group that did not (P = .66). One SMN (a melanoma located outside of the cranial radiation field) occurred in a patient who was randomly assigned to doxorubicin alone. No SMNs were observed in patients randomly assigned to receive dexrazoxane. CONCLUSION Dexrazoxane was not associated with an increased risk of SMNs in children treated for HR ALL. Given the potential importance of dexrazoxane as a cardioprotectant, we recommend that dexrazoxane continue to be used and studied in doxorubicin-containing pediatric regimens.

Phase 2 trial of clofarabine in combination with etoposide and cyclophosphamide in pediatric patients with refractory or relapsed acute lymphoblastic leukemia

The outcomes in children with refractory/relapsed (R/R) acute lymphoblastic leukemia (ALL) are dismal. The efficacy and safety of intravenous clofarabine 40 mg/m(2) per day, cyclophosphamide 440 mg/m(2) per day, and etoposide 100 mg/m(2) per day for 5 consecutive days in pediatric patients with R/R ALL was evaluated in this phase 2 study. The primary endpoint was overall response rate (complete remission [CR] plus CR without platelet recovery [CRp]). Among the 25 patients (median age, 14 years; pre-B cell ALL, 84%; ≥ 2 prior regimens: 84%; refractory to previous regimen: 60%), the overall response rate was 44% (7 CR, 4 CRp) with a 67.3-week median duration or remission censored at last follow-up. Most patients proceeded to alternative therapy, and 10 patients (40%) received hematopoietic stem cell transplantation. Six patients (24%) died because of treatment-related adverse events associated with infection, hepatotoxicity, and/or multiorgan failure. The study protocol was amended to exclude patients with prior hematopoietic stem cell transplantation after 4 of the first 8 patients developed severe hepatotoxicity suggestive of veno-occlusive disease. No additional cases of veno-occlusive disease occurred. The regimen offered encouraging response rates and sustained remission in R/R patients. Future investigation should include exploration of patient selection, dosing, and supportive care. This trial was registered at www.clinicaltrials.gov as #NCT00315705.

A multi-center phase I study of clofarabine, etoposide and cyclophosphamide in combination in pediatric patients with refractory or relapsed acute leukemia

This Phase I study of clofarabine with etoposide and cyclophosphamide for children with relapsed/refractory acute lymphoblastic leukemia (ALL) or acute myelogenous leukemia (AML) was conducted to determine the maximum tolerated dose (MTD), dose-limiting toxicities and the recommended phase 2 doses (RP2Ds). All three drugs were administered for five consecutive days in induction and four consecutive days in consolidation, for a maximum of eight cycles. A total of 25 patients (20 ALL and 5 AML) were enrolled in five cohorts. An MTD was not reached. The RP2Ds of clofarabine, cyclophosphamide and etoposide were 40, 440 and 100 mg/m2/day, respectively. Complete remission (CR) was achieved in 10 patients (ALL: nine; AML: one), and CR without platelet recovery in six patients (ALL: two; AML: four) for an overall response rate of 64% (ALL: 55%; AML: 100%). Of the 16 responders, 9 patients proceeded to hematopoietic stem cell transplantation. In conclusion, the combination of clofarabine, etoposide and cyclophosphamide was well tolerated and effective in pediatric patients with relapsed/refractory leukemia. Of note, the phase II portion of the trial was amended after the occurrence of unexpected hepatotoxicity. The ongoing phase II study will evaluate the efficacy and safety of this regimen in ALL patients.

Clofarabine in pediatric acute leukemia: Current findings and issues

Clofarabine is a second‐generation purine nucleoside analog and has significant anti‐leukemic activity as a single agent. It is approved by the United States Food and Drug Administration (FDA) for the treatment of relapsed or refractory acute lymphoblastic leukemia (ALL) in children. Combinations of clofarabine with purine nucleoside analogs or DNA‐damaging agents have been investigated utilizing synergistic effects and now tested in a number of studies including a frontline study. In this article, we review the development of clofarabine, rationale and history of combination regimens, and their potential roles and toxicities in the treatment of pediatric ALL that are important to treating clinicians. Pediatr Blood Cancer 2012;59:417–422.

Acute lymphoblastic leukemia in adolescents and young adults

Age at diagnosis remains one of the strongest prognostic factors in acute lymphoblastic leukemia (ALL), with older patients having inferior outcomes compared with younger patients. Adolescents and young adults (AYAs) with ALL (age 15–30 years) represent a patient subgroup with distinctive biology whose optimal therapy has yet to be determined. Compared with younger children with ALL, AYAs are more likely to present with unfavorable presenting characteristics (such as high presenting leukocyte counts, T-cell phenotype, and the Philadelphia chromosome). Additionally, AYAs with ALL experience more regimen-related toxicity than younger patients. Recent retrospective studies suggest that patients age 15 to 21 years treated on pediatric ALL regimens have better outcomes than similarly aged patients treated on adult ALL regimens. Pilot prospective studies are under way to test the feasibility of administering pediatric ALL regimens to AYAs with ALL, with promising preliminary results.