Phase I trial of temozolomide and protracted irinotecan in pediatric patients with refractory solid tumors

A Multicenter Randomized Bioequivalence Study of a Novel Ready-to-Use Temozolomide Oral Suspension vs. Temozolomide Capsules

BACKGROUND

Temozolomide (TMZ) oral suspension (Ped-TMZ, KIZFIZO®) is being developed for the treatment of relapsed or refractory neuroblastoma, a rare cancer affecting infants and young children. The study assessed the safety and the bioequivalence of this novel pediatric formulation with existing TMZ oral capsules.

METHODS

In vitro dissolution profiles and the bioequivalence were evaluated following the European Medicines Agency "Guidelines on the investigation of Bioequivalence". The phase I, multicenter, randomized, open-label, crossover, single-dose bioequivalence study enrolled 36 adult patients with glioblastoma multiforme or lower-grade glioma. Each patient received 200 mg/m2 Ped-TMZ suspension and TMZ capsules (Temodal®) on 2 consecutive days, with the order being randomly assigned. Fourteen blood samples were collected up to 10 h post-dosing. Bioequivalence was assessed by comparing the 90% confidence interval for the ratio of the geometric means of maximum TMZ plasma concentration (Cmax) and the area under the curve (AUCt). Other endpoints included further pharmacokinetic parameters and safety.

RESULTS

Both formulations exhibited a fast in vitro dissolution profile with more than 85% of TMZ dissolved within 15 min. For the bioequivalence study, thirty patients completed the trial as per the protocol. The ratio of Ped-TMZ/TMZ capsule geometric means (90% CI) for AUCt and Cmax were 97.18% (95.05-99.35%) and 107.62% (98.07-118.09%), respectively, i.e., within the 80-125% bioequivalence limits. No buccal toxicity was associated with Ped-TMZ liquid formulation.

CONCLUSIONS

This study showed that Ped-TMZ oral suspension and TMZ oral capsule treatment are immediate release and bioequivalent medicines. There were also no unexpected safety signals or local toxicity (funded by ORPHELIA Pharma; ClinicalTrials.gov number, NCT04467346).

A phase I trial of metformin in combination with vincristine, irinotecan, and temozolomide in children with relapsed or refractory solid and central nervous system tumors: A report from the national pediatric cancer foundation

BACKGROUND

Patients with relapsed and refractory solid and central nervous system (CNS) tumors have poor outcomes and need novel therapeutic options. Vincristine, irinotecan, and temozolomide (VIT) is a common chemotherapy regimen in relapsed pediatric tumors with an established toxicity profile. Metformin shows preclinical anti-cancer activity through multiple pathways.

METHODS

The objective of this Phase I trial was to establish the maximum tolerated dose (MTD) and recommended Phase II dose (RP2D) of metformin in combination with VIT in children with relapsed and refractory solid and CNS tumors. A 3 + 3 design was used to test the addition of metformin at five dose levels (666, 999, 1333, 1666, and 2000 mg/m² /day). Therapy toxicity, pharmacokinetics, and radiologic response to treatment were evaluated.

RESULTS

Twenty-six patients (median age 13 years, range 2-18 years) were enrolled with 22 evaluable for toxicity. The most common diagnoses were Ewing sarcoma (n = 8), rhabdomyosarcoma (n = 3) and atypical teratoid/rhabdoid tumor (n = 3). The MTD was exceeded at Dose Level 5 due to two dose-limiting toxicities; both were Grade 3 diarrhea requiring prolonged hospitalization and intravenous fluids. The MTD was not determined due to study closure with less than six patients enrolled at Dose Level 4. Frequently observed toxicities were gastrointestinal (most notably diarrhea) and hematologic. Amongst 16 patients evaluable for best overall response, there was one complete response (Ewing sarcoma), three partial responses (Ewing sarcoma, glioblastoma multiforme, and alveolar rhabdomyosarcoma), and five patients with stable disease.

CONCLUSIONS

The MTD of VIT with metformin was not determined due to premature study closure. We recommend an RP2D of Dose Level 4, 1666 mg/m² /day. Radiographic responses were seen in multiple tumor types. Further evaluation for efficacy could be investigated in a Phase II trial.

SELNET clinical practice guidelines for bone sarcoma

Bone sarcoma are infrequent diseases, representing < 0.2% of all adult neoplasms. A multidisciplinary management within reference centers for sarcoma, with discussion of the diagnostic and therapeutic strategies within an expert multidisciplinary tumour board, is essential for these patients, given its heterogeneity and low frequency. This approach leads to an improvement in patient's outcome, as demonstrated in several studies. The Sarcoma European Latin-American Network (SELNET), aims to improve clinical outcome in sarcoma care, with a special focus in Latin-American countries. These Clinical Practice Guidelines (CPG) have been developed and agreed by a multidisciplinary expert group (including medical and radiation oncologist, surgical oncologist, orthopaedic surgeons, radiologist, pathologist, molecular biologist and representatives of patients advocacy groups) of the SELNET consortium, and are conceived to provide the standard approach to diagnosis, treatment and follow-up of bone sarcoma patients in the Latin-American context.

Systemic Treatment of Ewing Sarcoma: Current Options and Future Perspectives

Ewing sarcoma (ES) is an uncommon malignant neoplasm, mostly affecting young adults and adolescents. Surgical excision, irradiation, and combinations of multiple chemotherapeutic agents are currently used as a multimodal strategy for the treatment of local and oligometastatic disease. Although ES usually responds to the primary treatment, relapsed and primarily refractory disease remains a difficult therapeutic challenge. The growing understanding of cancer biology and the subsequent development of new therapeutic strategies have been put at the service of research in recurrent and refractory ES, generating a great number of ongoing studies with compounds that could find superior clinical outcomes in the years to come. This review gathers the current available information on the treatment and clinical investigation of ES and aims to be a point of support for future research.

Front-Line Window Therapy with Temozolomide and Irinotecan in Patients with Primary Disseminated Multifocal Ewing Sarcoma: Results of the ISG/AIEOP EW-2 Study

PURPOSE

The main objective was to evaluate the activity and tolerability of TEMIRI as a front-line treatment in primary disseminated Ewing sarcoma (PDMES) using the RECIST 1.1 criteria. The secondary objectives included the assessment of toxicity and the performance status/symptom changes.

METHODS

Between 2012 and 2018, patients with PDMES received two courses of temozolomide 100 mg/sqm/day + irinotecan 50 mg/sqm/day for 5 days every 3 weeks as an amendment to the Italian Sarcoma Group/Associazione Italiana EmatoIogia ed Oncologia Pediatrica (ISG/AIEOP) EW-2 protocol (EUDRACT#2009-012353-37, Vers. 1.02).

RESULTS

Thirty-four patients were enrolled. The median age at diagnosis was 19 years (range 3-55). After TEMIRI, the RECIST response was as follows: a partial response in 20 (59%) patients, stable disease in 11 (32%), and disease progression in 3 (9%). The ECOG/Lansky score was improved in 25/34 (73.5%) cases, and a reduction or disappearance of pain was observed in 31/34 patients (91%). The incidence of grade 3-4 toxicity was 3%. The 3-year event-free survival (EFS) and overall survival (OS) were 21% (95% CI 6-35%) and 36% (95% CI: 18-54%), respectively.

CONCLUSION

the smooth handling and encouraging activity demonstrated by up-front TEMIRI did not change the EFS in PDMES, so this result suggests the need for the further evaluation of the efficacy of TEMIRI in combination with conventional treatments in non-metastatic patients.

Ewing Sarcoma-Diagnosis, Treatment, Clinical Challenges and Future Perspectives

Ewing sarcoma, a highly aggressive bone and soft-tissue cancer, is considered a prime example of the paradigms of a translocation-positive sarcoma: a genetically rather simple disease with a specific and neomorphic-potential therapeutic target, whose oncogenic role was irrefutably defined decades ago. This is a disease that by definition has micrometastatic disease at diagnosis and a dismal prognosis for patients with macrometastatic or recurrent disease. International collaborations have defined the current standard of care in prospective studies, delivering multiple cycles of systemic therapy combined with local treatment; both are associated with significant morbidity that may result in strong psychological and physical burden for survivors. Nevertheless, the combination of non-directed chemotherapeutics and ever-evolving local modalities nowadays achieve a realistic chance of cure for the majority of patients with Ewing sarcoma. In this review, we focus on the current standard of diagnosis and treatment while attempting to answer some of the most pressing questions in clinical practice. In addition, this review provides scientific answers to clinical phenomena and occasionally defines the resulting translational studies needed to overcome the hurdle of treatment-associated morbidities and, most importantly, non-survival.

Registration-directed phase 1/2 trial of irinotecan for pediatric solid tumors

BACKGROUND

Although irinotecan hydrochloride (IRI) is a promising chemotherapeutic agent for pediatric solid tumors, its indications had been off-label in the USA, EU and Japan. Therefore, we conducted a phase 1/2 trial of IRI monotherapy in a registration-directed setting.

METHODS

Children aged 2-18 years with solid tumors who were either refractory to or relapsed after standard chemotherapy were enrolled. Phase 1 was a conventional dose escalation study to determine the dose-limiting toxicity (DLT) and the recommended dose. IRI was given i.v. on days 1, 2, 3 and 8, 9, 10 in up to eight, 21 day cycles.

RESULTS

The starting dose (40 mg/m² /day) was determined to be the recommended dose because the next higher dose level (45 mg/m² /day) resulted in two cases of DLT. Seventeen children (11 in phase 1 and six in phase 2) with a refractory solid tumor received IRI. Of the 12 patients treated with 40 mg/m² /day, seven (58.3%) achieved a stable disease condition for >8 weeks.

CONCLUSIONS

The RD of IRI in this treatment schedule was 40 mg/m² /day. IRI did not cause tumor shrinkage but might help to stabilize refractory pediatric solid tumors. Based on the accumulating evidence from international studies of the efficacy of IRI against refractory pediatric solid tumors, the Japanese regulatory authority approved its use for this indication in 2011.

Phase II Trial of Alisertib in Combination with Irinotecan and Temozolomide for Patients with Relapsed or Refractory Neuroblastoma

PURPOSE

In phase I testing, alisertib tablets with irinotecan and temozolomide showed significant antitumor activity in patients with neuroblastoma. This study sought to confirm activity of this regimen; evaluate an alisertib oral solution; and evaluate biomarkers of clinical outcomes.

PATIENTS AND METHODS

We conducted a two-stage phase II trial of alisertib tablets (60 mg/m2/dose × 7 days), irinotecan (50 mg/m2/dose i.v. × 5 days), and temozolomide (100 mg/m2/dose orally × 5 days) in patients with relapsed or refractory neuroblastoma. The primary endpoint was best objective response. A separate cohort was treated with alisertib at 45 mg/m2 using oral solution instead of tablets. Exploratory analyses sought to identify predictors of toxicity, response, and progression-free survival (PFS) using pooled data from phase I, phase II, and oral solution cohorts.

RESULTS

Twenty and 12 eligible patients were treated in the phase II and oral solution cohorts, respectively. Hematologic toxicities were the most common adverse events. In phase II, partial responses were observed in 19 evaluable patients (21%). The estimated PFS at 1 year was 34%. In the oral solution cohort, 3 patients (25%) had first cycle dose-limiting toxicity (DLT). Alisertib oral solution at 45 mg/m2 had significantly higher median C max and exposure compared with tablets at 60 mg/m2. Higher alisertib trough concentration was associated with first cycle DLT, whereas MYCN amplification was associated with inferior PFS.

CONCLUSIONS

This combination shows antitumor activity, particularly in patients with MYCN nonamplified tumors. Data on an alisertib oral solution expand the population able to be treated with this agent.

Autophagy modulates temozolomide-induced cell death in alveolar Rhabdomyosarcoma cells

Rhabdomyosarcoma (RMS) is a muscle-derived tumor. In both pre-clinical and clinical studies Temozolomide (TMZ) has been recently tested against RMS; however, the precise mechanism of action of TMZ in RMS remains unclear. Here we demonstrate that TMZ decreases the cell viability of the RH30 RMS and C2C12 cell line, where cells display evidence of mitochondrial outer membrane permeability. Interestingly, the C2C12 mouse myoblast line was relatively more resistant to TMZ-induced apoptosis. Moreover, we observed that TMZ activated biochemical and morphological markers of autophagy in both cell lines. Autophagy inhibition in both RH30 and C2C12 cells significantly increased TMZ-induced cell death. In RH30 cells, TMZ increased Mcl-1 and Bax protein expression compared to corresponding time match controls while in C2C12 Mcl-1, Bcl-2, Bcl-XL, and Bax protein expression were not changed. Baf-A1 co-treatment with TMZ significantly decrease Mcl-1 expression compared to TMZ while increase Bax expression in C2C12 cells (Bcl2 and Bcl-XL do not significantly change in Baf-A1/TMZ co-treatment). Using a three-dimensional (3D) C2C12 and RH30 culture model we demonstrated that TMZ is significantly more toxic in RH30 cells (live/dead assay). Additionally, we have observed in our 3D culture model that TMZ induced both apoptosis (cleavage of PARP) and autophagy (LC3-puncta and localization of LC3/p62). Therefore, our data demonstrate that TMZ induces simultaneous autophagy and apoptosis in both RH30 and C2C12 cells in 2D and 3D culture model, where RH30 cells are more sensitive to TMZ-induced death. Furthermore, autophagy serves to protect RH30 cells from TMZ-induced death.

Vincristine, irinotecan, and temozolomide treatment for refractory/relapsed pediatric solid tumors: A single center experience

BACKGROUND

Although the survival of pediatric cancer has increased dramatically in the last decades, the survival of refractory, relapsed, and metastatic cases is still dismal. The combination of irinotecan and temozolomide has shown activity against refractory/relapsed pediatric solid tumors.

METHOD

Thirty-four children with refractory/relapsed solid tumors who had previously been heavily pretreated and who were given vincristine, irinotecan, and temozolomide as third- or further line chemotherapy during 2004-2015 were evaluated.

RESULTS

Patients were diagnosed with Ewing sarcoma (n = 15), rhabdomyosarcoma (n = 8), neuroblastoma (n = 8), osteosarcoma (n = 2), and Wilms' tumor (n = 1). Thirty patients presented with disease progression on therapy and the other four presented with relapsing. A total of 141 cycles were administered. Radiotherapy was used in 17 patients and surgery in 4 as local therapy. Among all patients, 6 had complete response, 3 had partial response, 14 had stable disease, and 11 had progressive disease. The objective response was 26.4% (complete response + partial response) and median survival duration was six months. The first and second year overall survival rates were 22.3% and 16.8%. The objective response in Ewing sarcoma patients was 40%. Diarrhea was the most common toxicity and 14 (10%) courses were associated with grade 3-4 diarrhea.

CONCLUSIONS

In heavily pretreated patients with refractory/relapsed solid tumors, the vincristine, irinotecan, and temozolomide regimen seemed promising in Ewing sarcoma patients and was well tolerated.

Position paper: Rationale for the treatment of children with CCSK in the UMBRELLA SIOP-RTSG 2016 protocol

The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) has developed a new protocol for the diagnosis, treatment, and follow-up monitoring of childhood renal tumours - the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). This protocol has been designed to continue international collaboration in the treatment of childhood renal tumours and will be implemented in over 50 different countries. Clear cell sarcoma of the kidney, which is a rare paediatric renal tumour that most commonly occurs in children between 2 and 4 years of age, is specifically addressed in the UMBRELLA protocol.

STA-8666, a novel HSP90 inhibitor/SN-38 drug conjugate, causes complete tumor regression in preclinical mouse models of pediatric sarcoma

Long-term survival in patients with metastatic, relapsed, or recurrent Ewing sarcoma and rhabdomyosarcoma is dismal. Irinotecan, a topoisomerase 1 inhibitor, has activity in these sarcomas, but due to poor bioavailability of its active metabolite (SN-38) has had limited clinical efficacy. In this study we have evaluated the efficacy and toxicity of STA-8666, a novel drug conjugate which uses an HSP90 inhibitor to facilitate intracellular, tumor-targeted delivery of the topoisomerase 1 inhibitor SN-38, thus preferentially delivering and concentrating SN-38 within tumor tissue. We present in vivo evidence from mouse xenograft models that STA-8666 results in more persistent inhibition of topoisomerase 1 and prolonged DNA damage compared to irinotecan. This translates into superior antitumor efficacy and survival in multiple aggressive models of both diseases in mouse xenografts, as well as in an irinotecan-resistant model of pediatric osteosarcoma, demonstrated by dramatic tumor shrinkage, durable remission and prolonged complete regressions following short-term treatment, compared to conventional irinotecan. Gene expression analysis performed on xenograft tumors treated with either irinotecan or STA-8666 showed that STA-8666 affected expression of DNA damage and repair genes more robustly than irinotecan. These results suggest that STA-8666 may be a promising new agent for patients with pediatric-type sarcoma.

Irinotecan for relapsed Wilms tumor in pediatric patients: SIOP experience and review of the literature-A report from the SIOP Renal Tumor Study Group

While irinotecan has been studied in various pediatric solid tumors, its potential role in Wilms tumor (WT) is less clear. We evaluated response and outcome of irinotecan-containing regimens in relapsed WT and compared our results to the available literature. Among 14 evaluable patients, one complete response (CR) and two partial responses (PRs) were observed in patients with initial intermediate-risk (CR and PR) and blastemal-type histologies (PR). Two patients were alive at last follow-up showing no evidence of disease. Our results and the reviewed literature suggest some effectiveness of irinotecan in the setting of relapsed WT.

Combination of bevacizumab, irinotecan, and temozolomide for refractory or relapsed neuroblastoma: Results of a phase II study

BACKGROUND

The rationale for studying the combination of bevacizumab, irinotecan, and temozolomide (BIT) in neuroblastoma (NB) is based on the following: (i) vascular endothelial growth factor (VEGF) expression is associated with an aggressive phenotype, (ii) anti-VEGF antibody bevacizumab enhances irinotecan-mediated suppression of NB xenografts, (iii) bevacizumab safety has been established in pediatric phase I studies, and (iv) irinotecan + temozolomide (IT) is a standard salvage chemotherapy.

PROCEDURE

We conducted a phase II study of BIT in patients with measurable/evaluable refractory or relapsed high-risk NB (www.clinicaltrials.gov, NCT01114555). Each cycle consisted of bevacizumab (15 mg/kg intravenously [IV]) on days 1 and 15 plus irinotecan (50 mg/m2 /day IV) and temozolomide (150 mg/m2 /day orally) on days 4-8. Patients could have previously received, but not relapsed on, IT. An early stopping rule mandated continuing therapy only if more than five patients of 27 evaluable patients achieved partial response (PR) or complete response (CR) after four cycles.

RESULTS

Thirty-three heavily pretreated patients (nine primary refractory; 24 relapsed) received one to eight cycles of BIT. Toxicities were expected and transient. Grade 4 toxicities were neutropenia (30%) and thrombocytopenia (24%). Grade 3 toxicities included hepatic transaminitis (15%), proteinuria (9%), and diarrhea (3%). Overall responses were as follows: three CR (all in prior IT-treated patients), 18 no response, and 12 progressive disease. Only one of 23 patients assessable for the early stopping rule regarding efficacy achieved PR/CR, so patient accrual was discontinued. Median progression-free survival and overall survival was 7.7 ± 1.7 and 31.5 ± 5.6 months, respectively; all patients continued anti-NB therapy post-BIT.

CONCLUSIONS

BIT was well tolerated, but the addition of bevacizumab did not improve response rates in resistant NB compared to historical data for IT.

Temozolomide combined with irinotecan caused regression in an adult pleomorphic rhabdomyosarcoma patient-derived orthotopic xenograft (PDOX) nude-mouse model

Adult pleomorphic rhabdomyosarcoma (RMS) is a rare and recalcitrant, highly-malignant mesenchymal tumor in need of improved therapeutic strategies. Our laboratory pioneered the patient-derived orthotopic xenograft (PDOX) nude mouse model with the technique of surgical orthotopic implantation (SOI). We previously described the development of a PDOX model of adult pleomorphic RMS where the tumor behaved similar to the patient donor. A high-grade pleomorphic rhabdomyosarcoma from a striated muscle was previously grown orthotopically in the right biceps-femoris muscle of nude mice to establish the PDOX model. In the present study, the PDOX models were randomized into the following treatment groups when tumor volume reached 100 mm³: G1, control without treatment; G2, cyclophosphamide (CPA) 140 mg/kg, intraperitoneal (i.p.) injection, weekly, for 3 weeks; G3, temozolomide (TEM), 25 mg/kg, per oral (p.o.), daily, for 21 days; G4, temozolomide (TEM) 25 mg/kg, p.o., daily, for 21 days combined with irinotecan (IRN), 4 mg/kg, i.p., daily for 21 days. After 3 weeks, treatment of PDOX with TEM combined with IRN was so powerful that it resulted in tumor regression and the smallest tumor volume compared to other groups. The RMS PDOX model should be of use to design the treatment program for the patient and for drug discovery and evaluation for this recalcitrant tumor type.

A comparison of safety and efficacy of cytotoxic versus molecularly targeted drugs in pediatric phase I solid tumor oncology trials

BACKGROUND

Prior reviews of phase I pediatric oncology trials involving primarily cytotoxic agents have reported objective response rates (ORRs) and toxic death rates of 7.9-9.6% and 0.5%, respectively. These data may not reflect safety and efficacy in phase I trials of molecularly targeted (targeted) drugs.

METHODS

A systematic review of pediatric phase I solid tumor trials published in 1990-2013 was performed. The published reports were evaluated for patient characteristics, toxicity information, and response numbers.

RESULTS

A total of 143 phase I pediatric clinical trials enrolling 3,896 children involving 53 targeted and 48 cytotoxic drugs were identified. A meta-analysis demonstrated that the ORR is 2.1-fold higher with cytotoxic drugs (0.066 vs. 0.031 per subject; P = 0.007). By contrast, the pooled estimate of the stable disease rate (SDR) is similar for cytotoxic and targeted drugs (0.2 vs. 0.23 per subject; P = 0.27).  The pooled estimate of the dose-limiting toxicity rate is 1.8-fold larger with cytotoxic drugs (0.24 vs. 0.13 per subject; P = 0.0003). The hematologic grade 3-4 (G3/4) toxicity rate is 3.6-fold larger with cytotoxic drugs (0.43 vs. 0.12 per treatment course; P = 0.0001); however, the nonhematologic G3/4 toxicities and toxic deaths occur at similar rates for cytotoxic and targeted drugs.

CONCLUSIONS

In phase I pediatric solid tumor trials, ORRs were significantly higher for cytotoxic versus targeted agents. SDRs were similar in targeted and cytotoxic drug trials. Patients treated with cytotoxic agents were more likely to experience hematologic G3/4 toxicities than those patients receiving targeted drugs.

Management of Ewing sarcoma family of tumors: Current scenario and unmet need

Ewing sarcoma family tumors (ESFT) are heterogeneous, aggressive group of disease with peak incidence in adolescent and young adults. The outcome has been improved dramatically from 10% with surgery and radiotherapy alone to 65%-70% now, in localized disease, with the introduction of chemotherapy. Chemotherapy regimen evolved from single agent to multiagent with effort of many cooperative clinical trials over decades. The usual treatment protocol include introduction of multi-agent chemotherapy in neoadjuvant setting to eradicate systemic disease with timely incorporation of surgery and/or radiotherapy as local treatment modality and further adjuvant chemotherapy to prevent recurrence. Risk adapted chemotherapy in neoadjuvant and adjuvant setting along with radiotherapy has been used in many international collaborative trials and has resulted in improved outcome, more so in patients with localized disease. The role of high dose chemotherapy with stem cell rescue is still debatable. The outcome of patients with metastatic disease is dismal with long term outcome ranges from 20%-40% depending on the sites of metastasis and intensity of treatment. There is a huge unmet need to improve outcome further, more so in metastatic setting. Novel therapy targeting the molecular pathways and pathogenesis of ESFT is very much required. Here we have discussed the current standard of management in patients with ESFT, investigational targeted or novel therapies along with future promises.

Preclinical Justification of pbi-shRNA EWS/FLI1 Lipoplex (LPX) Treatment for Ewing's Sarcoma

The EWS/FLI1 fusion gene is well characterized as a driver of Ewing's sarcoma. Bi-shRNA EWS/FLI1 is a functional plasmid DNA construct that transcribes both siRNA and miRNA-like effectors each of which targets the identical type 1 translocation junction region of the EWS/FLI1 transcribed mRNA sequence. Previous preclinical and clinical studies confirm the safety of this RNA interference platform technology and consistently demonstrate designated mRNA and protein target knockdown at greater than 90% efficiency. We initiated development of pbi-shRNA EWS/FLI1 lipoplex (LPX) for the treatment of type 1 Ewing's sarcoma. Clinical-grade plasmid was manufactured and both sequence and activity verified. Target protein and RNA knockdown of 85-92% was demonstrated in vitro in type 1 human Ewing's sarcoma tumor cell lines with the optimal bi-shRNA EWS/FLI1 plasmid. This functional plasmid was placed in a clinically tested, liposomal (LP) delivery vehicle followed by in vivo verification of activity. Type 1 Ewing's sarcoma xenograft modeling confirmed dose related safety and tumor response to pbi-shRNA EWS/FLI1 LPX. Toxicology studies in mini-pigs with doses comparable to the demonstrated in vivo efficacy dose resulted in transient fever, occasional limited hypertension at low- and high-dose assessment and transient liver enzyme elevation at high dose. These results provide the justification to initiate clinical testing.

Three-year Follow up of GMCSF/bi-shRNA(furin) DNA-transfected Autologous Tumor Immunotherapy (Vigil) in Metastatic Advanced Ewing's Sarcoma

Ewing's sarcoma is a devastating rare pediatric cancer of the bone. Intense chemotherapy temporarily controls disease in most patients at presentation but has limited effect in patients with progressive or recurrent disease. We previously described preliminary results of a novel immunotherapy, FANG (Vigil) vaccine, in which 12 advanced stage Ewing's patients were safely treated and went on to achieve a predicted immune response (IFNγ ELISPOT). We describe follow-up through year 3 of a prospective, nonrandomized study comparing an expanded group of Vigil-treated advanced disease Ewing's sarcoma patients (n = 16) with a contemporaneous group of Ewing's sarcoma patients (n = 14) not treated with Vigil. Long-term follow-up results show a survival benefit without evidence of significant toxicity (no ≥ grade 3) to Vigil when administered once monthly by intradermal injection (1 × 10e(6) cells/injection to 1 × 10e(7) cells/injection). Specifically, we report a 1-year actual survival of 73% for Vigil-treated patients compared to 23% in those not treated with Vigil. In addition, there was a 17.2-month difference in overall survival (OS; Kaplan-Meier) between the Vigil (median OS 731 days) and no Vigil patient groups (median OS 207 days). In conclusion, these results supply the rational for further testing of Vigil in advanced stage Ewing's sarcoma.

Can Fluorine-18-Fluorodeoxyglucose PET Be Used As a Useful Method to Evaluate the Treatment Response to Neoadjuvant Therapy Combined With Sorafenib and Antivegf in Children Diagnosed With Metastatical Bone Sarcoma?

Background

The prognosis is still poor for patients with a metastatic bone tumor and new treatment approaches (anti-VEGF and tyrosine kinase inhibitors vs) are therefore needed.

Objectives

The aim of our study was to evaluate how the primary and metastatic lesions of our patients with a bone tumor were affected by these treatments and to determine the importance of the 18F-FDG PET method.

Patients and Methods

Twenty metastatic bone tumor cases were included. Sorafenib and anti-VEGF were added to the standard treatment in cases with widespread metastatic disease at diagnosis or after neoadjuvant chemotherapy showing less than 90% tumor necrosis in the surgical sample. Positron emission tomography (PET) imaging was performed at diagnosis, the preoperative period following neoadjuvant chemotherapy, during postoperative follow-up, and when treatment was discontinued.

Results

The primary treatment region median SUVmax level decreased from 7.35 to 2.5 in the living patients (n = 16) while there was no significant decrease in the patients who succumbed to the disease (P < 0.001). Comparison of the pre- and post-treatment metastasis region median SUVmax levels in patients with metastatic involvement showed a decrease from 2.1 to 0 in the surviving patients but only from 4.8 to 3.2 in the deceased patients (P < 0.01). Survival results indicated that 28.6% of the patients receiving classical treatment only died while all the patients receiving additional sorafenib and anti-VEGF survived.

Conclusions

18F-PET may be a useful technique before and during the follow-up of neoadjuvant treatment in pediatric metastatic bone tumor patients. The addition of sorafenib and anti-VEGF to classical treatment has a favorable contribution to the response and therefore the survival duration.

Irinotecan and temozolamide treatment for relapsed Ewing sarcoma: a single-center experience and review of the literature

Long-term survival in relapsed Ewing sarcoma (ES) is less than 20%. Encouraging results have been reported with irinotecan and temozolomide combinations (IRN/TMZ). We aimed to share our experience and compare it with previously published studies using this combination to treat relapsed ES. We retrospectively evaluated 20 patients treated with a combination of IRN (20 mg/m(2)/d × 5 for 2 weeks) and temozolomide (100 mg/m(2)/d × 5). Patients received a total of 97 courses. An objective response was achieved in 11 patients (55%) and maintained for a median of 12 months. Five patients were alive for a median of 12 months. Median time to progression was 5.5 (2-57) months. After the IRN/TMZ treatment, 1-year overall and event-free survival rates were 54.2% and 44.4%, respectively. Grade 3-4 toxicities included diarrhea (9.2%), neutropenia (11.3%), and thrombocytopenia (6.2%). Three retrospective trials were found in our literature review, which used an IRN/TMZ combination to treat ES. There was one other study which retrospectively evaluated the efficacy of vincristine, IRN, and TMZ combination in relapsed ES. A total of 81 patients were treated with IRN/TMZ in four studies including ours. The objective response rate was 55.1%, and median time to progression ranged from 5.5 to 8.3 months. Twenty-six (7.5%) of a total of 346 courses were associated with grade 3-4 diarrhea. Grade 3-4 neutropenia and thrombocytopenia were reported in 9.2% and 7.2% of the courses, respectively. Results showed that an IRN/TMZ combination is effective and tolerable in patients with relapsed ES.

Phase I/II study of (131)I-MIBG with vincristine and 5 days of irinotecan for advanced neuroblastoma

Background:

¹³¹I-metaiodobenzylguanidine (MIBG) is an active radiopharmaceutical in neuroblastoma. A previous study demonstrated that MIBG could be combined with vincristine and prolonged irinotecan, although 25% of first courses had grade 3 diarrhoea. The current phase I/II study evaluated MIBG with vincristine and 5 days of higher-dose irinotecan.

Methods:

Patients 1–30 years old with advanced neuroblastoma were eligible. Patients received cefixime on days −1 to +6, irinotecan (50 mg m⁻² per dose IV) on days 0–4, vincristine (2 mg m⁻²) on day 0, MIBG (555 or 666 MBq kg⁻¹) on day 1, and peripheral blood stem cells on day 13. UGT1A1 genotyping was performed in consenting patients.

Results:

Thirty-two patients (12 phase I ; 20 phase II) received 42 courses. No dose-limiting toxicities were seen during dose escalation and the recommended administered activity was 666 MBq kg⁻¹. Myelosuppression and diarrhoea were the most common toxicities, with grade 3 diarrhoea in 6% of first courses. Patients homozygous for UGT1A1*28 had more grade 4 thrombocytopenia (80% vs 37% P=0.14). Responses (five complete and four partial) occurred in 9 out of 32 (28%) patients.

Conclusions:

MIBG (666 MBq kg⁻¹) with vincristine and this irinotecan schedule is tolerable and active, with less severe diarrhoea compared with a regimen using more protracted irinotecan.

Phase 1 evaluation of EZN-2208, a polyethylene glycol conjugate of SN38, in children adolescents and young adults with relapsed or refractory solid tumors

BACKGROUND

EZN-2208 is a water-soluble PEGylated conjugate of the topoisomerase inhibitor SN38, the active metabolite of irinotecan. Compared to irinotecan, EZN-2208 has a prolonged half-life permitting extended exposure to SN38. EZN-2208 has demonstrated clinical tolerability and antitumor activity in adults with advanced solid tumors. This Phase 1 study evaluated the safety, pharmacokinetics, and preliminary antitumor activity of EZN-2208 in children with relapsed or refractory solid tumors.

PROCEDURE

EZN-2208 was administered as a 1-hour intravenous infusion once every 21 days at five dose levels (12-30 mg/m(2) ). Filgrastim or pegfilgrastim was administered 24-48 hours after treatment with EZN-2208. The rolling-six design was used for dose determination.

RESULTS

Thirty eligible patients (15 females; median [range] age 11.5 years [2-21 years]) were treated with EZN-2208. Dose-limiting diarrhea occurred in one patient receiving 16 mg/m(2) and dose-limiting dehydration was seen in one patient receiving 24 mg/m(2) . At dose levels above 16 mg/m(2) , Grade ≥3 myelosuppression was demonstrated in the majority of patients. Additional adverse events included nausea, vomiting, and fatigue. The maximum tolerated dose was identified as 24 mg/m(2) due to dose-limiting thrombocytopenia in two patients receiving 30 mg/m(2) . Two of nine patients with neuroblastoma who were evaluable for response had partial responses. Five patients (four with neuroblastoma) remained on study for ≥8 cycles.

CONCLUSIONS

EZN-2208 was generally well-tolerated and was associated with clinical benefit in patients with neuroblastoma.

Phase I dose escalation and pharmacokinetic study of oral gefitinib and irinotecan in children with refractory solid tumors

PURPOSE

This phase I study endeavored to estimate the maximum tolerated dose and describe the dose-limiting toxicities (DLTs) of oral irinotecan with gefitinib in children with refractory solid tumors.

METHODS

Oral irinotecan was administered on days 1-5 and 8-12 with oral gefitinib (fixed dose, 150 mg/m(2)/day) on days 1-12 of a 21-day course. The escalation with overdose control method guided irinotecan dose escalation (7 dose levels, range 5-40 mg/m(2)/day).

RESULTS

Sixteen of 19 patients were evaluable, with serial pharmacokinetic studies in ten patients. Diagnoses included osteosarcoma (N = 5), neuroblastoma (N = 3), sarcoma (N = 3), and others (N = 5). Patients received a median of two courses (range 1-20), with at least two patients treated on dose levels 2-7. Three patients had five DLTs; the most common being metabolic (hypokalemia, N = 2 and hypophosphatemia, N = 1) at dose levels two (10 mg/m(2)) and four (20 mg/m(2)). One patient experienced grade 3 diarrhea (40 mg/m(2)). Irinotecan bioavailability was 2.5-fold higher when co-administered with gefitinib, while the conversion rate of irinotecan to SN-38 lactone was unaffected. The study closed due to poor accrual before evaluation of the next recommended irinotecan dose level (35 mg/m(2)). Of 11 patients receiving at least two courses of therapy, three had stable disease lasting two to four courses and one patient maintained a complete response through 18 courses.

CONCLUSIONS

The combination of oral gefitinib and irinotecan has acceptable toxicity and anti-tumor activity in pediatric patients with refractory solid tumors. Pharmacokinetic analysis confirms that co-administration of gefitinib increases irinotecan bioavailability leading to an increased SN-38 lactone systemic exposure.

Treatment of multiply relapsed wilms tumor with vincristine, irinotecan, temozolomide and bevacizumab

As most active chemotherapy agents against Wilms tumor are incorporated into upfront therapy, particularly for those patients with high risk for recurrence, novel regimens are needed to treat children with relapsed Wilms tumor. We describe four consecutive patients with multiply relapsed Wilms tumor who were treated with a combination of vincristine, irinotecan, temozolomide, and bevacizumab. Two had a complete response, and two had a partial response to treatment. Hematological toxicity and diarrhea were the main side effects. This regimen has activity in patients with multiply relapsed Wilms tumor without excessive toxicity, and should be evaluated further in this setting.

A phase I study of vincristine, irinotecan, temozolomide and bevacizumab (vitb) in pediatric patients with relapsed solid tumors

Background

To determine the maximum tolerated dose (MTD) and dose limiting toxicity (DLT) of irinotecan administered in combination with vincristine, temozolomide and bevacizumab in children with refractory solid tumors.

Methods

The study design included two dose levels (DL) of irinotecan given intravenously once daily for 5 consecutive days (DL1: 30 mg/m², and DL2: 50 mg/m²), combined with vincristine 1.5 mg/m² on days 1 and 8, temozolomide 100 mg/m² on days 1-5, and bevacizumab 15mg/kg on day 1, administered every 21 days for a maximum of 12 cycles.

Results

Thirteen patients were enrolled and 12 were evaluable for toxicity Dose limiting toxicity observed included grade 3 hyperbilirubinemia in 1 of 6 patients on DL1, and grade 3 colitis in 1 of 6 patients on DL2. DL 2 was the determined MTD. A total of 87 cycles were administered. Myelosuppression was mild. Grade 1-2 diarrhea occurred in the majority of cycles with grade 3 diarrhea occurring in only one cycle. Grade 2 hypertension developed in two patients. Severe hemorrhage, intestinal perforation, posterior leukoencephalopathy or growth plate abnormalities were not observed. Objective responses were noted in three Wilms tumor patients and one each of medulloblastoma and hepatocellular carcinoma. Five patients completed all 12 cycles of protocol therapy.

Conclusions

Irinotecan 50 mg/m²/day for 5 days was the MTD when combined with vincristine, temozolomide and bevacizumab administered on a 21 day schedule. Encouraging anti-tumor activity was noted.

Trial Registration

ClinicalTrials.gov; NCT00993044; http://clinicaltrials.gov/show/NCT00993044

Phase II study of irinotecan in combination with temozolomide (TEMIRI) in children with recurrent or refractory medulloblastoma: a joint ITCC and SIOPE brain tumor study

BACKGROUND

This multicenter phase II study investigated temozolomide + irinotecan (TEMIRI) treatment in children with relapsed or refractory medulloblastoma.

METHODS

Patients received temozolomide 100-125 mg/m(2)/day (days 1-5) and irinotecan 10 mg/m(2)/day (days 1-5 and 8-12) every 3 weeks. The primary endpoint was tumor response within the first 4 cycles confirmed ≥4 weeks and assessed by an external response review committee (ERRC). In a 2-stage Optimum Simon design, ≥6 responses in the first 15 evaluable patients were required within the first 4 cycles for continued enrollment; a total of 19 responses from the first 46 evaluable patients was considered successful.

RESULTS

Sixty-six patients were treated. Seven responses were recorded during stage 1 and 15 in the first 46 ERRC evaluated patients (2 complete responses and 13 partial responses). The objective response rate during the first 4 cycles was 32.6% (95% confidence interval [CI], 19.5%-48.0%). Median duration of response was 27.0 weeks (7.7-44.1 wk). In 63 patients evaluated by local investigators, the objective response rate was 33.3% (95% CI, 22.0%-46.3%), and 68.3% (95% CI, 55.3%-79.4%) experienced clinical benefit. Median survival was 16.7 months (95% CI, 13.3-19.8). The most common grade 3 treatment-related nonhematologic adverse event was diarrhea (7.6%). Grade 3/4 treatment-related hematologic adverse events included neutropenia (16.7%), thrombocytopenia (12.1%), anemia (9.1%), and lymphopenia (9%).

CONCLUSIONS

The planned study primary endpoint was not met. However, its tolerability makes TEMIRI a suitable candidate chemotherapy backbone for molecularly targeted agents in future trials in this setting.

An Unusual Location of Extraosseous Ewing's Sarcoma

Ewing's sarcoma (ES) is the second most common malignant bone tumor in children and young adults. ES also occurs as a primary soft tissue neoplasm without involvement of bone. We report the second case of extraosseous (EO) ES emerging from the omentum and a review of the relevant literature. EO ES should be included in the differential diagnosis of soft tissue neoplasms in the abdomen.

Vincristine, irinotecan, and temozolomide for treatment of relapsed alveolar rhabdomyosarcoma

Event-free survival for recurrent alveolar rhabdomyosarcoma (ARMS) is poor, and a consensus approach to treatment in the relapse setting has not been established. Recent studies suggest that a combination regimen of vincristine, irinotecan, and temozolomide (VITA) is active against recurrent sarcomas. We present our single-institution experience with this regimen for relapsed ARMS in heavily pretreated patients, including those with prior exposure to a combination regimen of vincristine and irinotecan. We observed a complete radiographic response in 1 of 4 patients who received VITA as a fifth attempted salvage regimen. Radiographic remission for the responsive patient was sustained for 27 weeks before disease recurrence. All therapies were administered in the outpatient setting and no grade III or grade IV toxicities were observed. These findings suggest that for patients with refractory ARMS, VITA in combination should be among the treatment options considered. They also reinforce the need for biological correlates to prospectively identify patients who may benefit from this treatment.

[Irinotecan plus temozolomide in refractory or relapsed pediatric solid tumors]

INTRODUCTION

The prognosis of refractory or relapsed pediatric solid tumors is very poor, and there is no standard treatment for this condition. The combination of irinotecan and temozolomide has proved useful in adults as a second-line treatment of different solid tumors. In pediatric patients, this combination has been effective in Ewing's sarcoma, neuroblastoma, and relapsed or refractory rhabdomyosarcoma.

PATIENTS AND METHODS

A retrospective study was conducted on 32 pediatric patients with refractory or relapsed solid tumors, who were treated with irinotecan and temozolomide in the Oncology Department at Children's Hospital Niño Jesus from September 2005 to June 2012. The clinical characteristics, treatment performed, toxicity and outcome, were analyzed.

RESULTS

Thirty-two patients received a total of 180 cycles. Of the 30 evaluable patients, 10 (33%) had a positive response (2 complete remission and 8 partial remission), and in 8 (27%) the disease remained stable. Almost all (94%) of the patients achieved a response in the first four cycles. Of the 180 cycles analyzed, only 50 (28%) had toxicity, and of these only 15 (8%) were grade iii-iv. The most common toxicity was diarrhea appearing in 18 patients. All patients received ambulatory treatment, except three of them who required hospitalization due to symptoms of their underlying disease.

CONCLUSION

The combination of irinotecan and temozolomide is well tolerated and active against pediatric refractory or relapsed solid tumors.

Temozolomide and unusual indications: review of literature

Temozolomide (TMZ) was first known to be useful as a radiosensitiser in both primary brain tumours like glioblastoma multiforme and oligodendroglioma. Later, TMZ proved its efficacy in the treatment of melanoma. Multiple publications have demonstrated the benefit of TMZ in terms of efficacy and tolerance (used as mono-therapy or as adjuvant chemotherapy) compared to the "gold standard" treatment of this kind of tumours. Furthermore, several recent clinical trials have shown the particular importance of TMZ in other types of cancer. This publication deals with the use of TMZ in cancers which are not formal indications for TMZ (excluding glioblastoma multiforme, oligodendroglioma and melanoma). It also includes a necessary review of recent literature about the role of TMZ in the treatment of brain metastases, lymphomas, refractory leukaemia, neuroendocrine tumours, pituitary tumours, Ewing's sarcoma, primitive neuroectodermal tumours, lung cancer and other tumours.

Dose escalation of intravenous irinotecan using oral cefpodoxime: a phase I study in pediatric patients with refractory solid tumors

BACKGROUND

Administration of an oral cephalosporin allowed advancement of the dosage of oral irinotecan. This study investigates whether administration of an oral cephalosporin increases the maximum tolerated dose (MTD) of intravenous irinotecan.

PROCEDURE

Irinotecan was administered intravenously on Days 1-5 and Days 8-12 of a 21-day cycle with continuous oral cefpodoxime starting 2 days prior to irinotecan. Cohorts of 3-6 pediatric patients with refractory solid tumors were enrolled at 4 dosage levels, starting at the single-agent irinotecan MTD of 20 mg/m(2) /dose.

RESULTS

The 17 evaluable patients received 39 courses of therapy. None of the patients treated with 20 mg/m(2) /dose experienced dose-limiting toxicity (DLT). One of six patients treated at 30 mg/m(2) /dose experienced dose-limiting neutropenia. Two of three patients treated with 45 mg/m(2) /dose and two of five treated with 40 mg/m(2) /dose experienced dose-limiting diarrhea, with associated dehydration and anorexia. Two unconfirmed partial responses were observed after one course in a patient with Ewing sarcoma and one with paraganglioma. A child with refractory neuroblastoma had disease stabilization through 12 courses of therapy. Median (range) systemic exposure to SN-38 at the MTD (30 mg/m(2) /dose) was 67 ng-h/mL (36 to 111 ng-h/mL).

CONCLUSIONS

The MTD of intravenous irinotecan administered on a protracted schedule was increased by 50% from 20 to 30 mg/m(2) /dose with the addition of oral cefpodoxime. The most prominent DLT remained diarrhea. High interpatient variability in irinotecan pharmacokinetics was observed; however, SN-38 exposure at the MTD was greater than most reported exposures with the 20 mg/m(2) dosage.

Comprehensive analysis of published phase I/II clinical trials between 1990-2010 in osteosarcoma and Ewing sarcoma confirms limited outcomes and need for translational investment

Background

High grade primary bone sarcomas are rare cancers that affect mostly children and young adults. Osteosarcoma and Ewing sarcoma are the most common histological subtypes in this age group, with current multimodality treatment strategies achieving 55-70% overall survival. As there remains an urgent need to develop new therapeutic interventions, we have reviewed published phase I/II trials that have been reported for osteosarcoma and Ewing sarcoma in the last twenty years.

Results

We conducted a literature search for clinical trials between 1990 and 2010, either for trials enrolling bone sarcoma patients as part of a general sarcoma indication or trials specifically in osteosarcoma and Ewing sarcoma. We identified 42 clinical trials that fulfilled our search criteria for general sarcoma that enrolled these patient groups, and eight and twenty specific trials for Ewing and osteosarcoma patients, respectively. For the phase I trials which enrolled different tumour types our results were incomplete, because the sarcoma patients were not mentioned in the PubMed abstract. A total of 3,736 sarcoma patients were included in these trials over this period, 1,114 for osteosarcoma and 1,263 for Ewing sarcoma. As a proportion of the worldwide disease burden over this period, these numbers reflect a very small percentage of the potential patient recruitment, approximately 0.6% for Ewing sarcoma and 0.2% for osteosarcoma. However, these data show an increase in recent activity overall and suggest there is still much room for improvement in the current trial development structures.

Conclusion

Lack of resources and commercial investment will inevitably limit opportunity to develop sufficiently rapid improvements in clinical outcomes. International collaboration exists in many well founded co-operative groups for phase III trials, but progress may be more effective if there were also more investment of molecular and translational research into disease focused phase I/II clinical trials. Examples of new models for early translational and early phase trial collaboration include the European based EuroBoNeT network, the Sarcoma Alliance for Research through Collaboration network (SARC) and the new European collaborative translational trial network, EuroSarc.

PPARgamma in Neuroblastoma

Neuroblastoma (NB) is the most common extracranial tumor in children and accounts for around 15% of all paediatric oncology deaths. The treatment of NB includes surgery, chemotherapy, and radiotherapy. Unfortunately, most children with NB present with advanced disease, and more than 60% of patients with high-risk features will have a poor prognosis despite intensive therapy. Agonists of the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) have been shown to have pleiotropic effects, including antineoplastic effects. The studies that addressed the role and the possible mechanism(s) of action of PPARgamma in NB cells are reviewed.

High-dose carboplatin-irinotecan-temozolomide: treatment option for neuroblastoma resistant to topotecan

BACKGROUND

We report a retrospective study of a novel regimen for neuroblastoma (NB) resistant to standard induction or salvage chemotherapy which now routinely includes topotecan.

PATIENTS AND METHODS

Forty-five patients received carboplatin (500 mg/m(2)/day, 2×)-irinotecan (50 mg/m(2)/day, 5×)-temozolomide (250 mg/m(2)/day, 5×) (HD-CIT). Only one course was planned. Patients with thrombocytopenia indicative of poor bone marrow (BM) reserve resulting from extensive prior therapy received peripheral blood stem cells (PBSCs) post-HD-CIT.

RESULTS

Modest acute toxicity allowed outpatient treatment. Low-grade diarrhea was common; there was no mucositis, nephrotoxicity, or cardiotoxicity. Myelosuppression was prolonged but uncomplicated. The absolute neutrophil count reached 500/µl on days 20-30 (median, 25) in 25 patients with satisfactory BM reserve, and on days 9-14 (median, 11) post-PBSC infusion. Anti-NB activity was common against refractory (non-progressing) disease or new relapse occurring off therapy (68% objective response rate), but not against disease progressing on therapy. Seven of 26 patients treated for refractory NB are progression-free and in complete remission following subsequent therapy, including anti-G(D2) immunotherapy, at ≥ 29+ months post-HD-CIT.

CONCLUSIONS

HD-CIT is appealing as salvage or consolidative therapy because of anti-NB activity and modest non-hematologic toxicity. PBSC support is unnecessary when BM reserve is intact. The wide antineoplastic activity of its three components and their potential for activity against disease in the central nervous system support applicability to other cancers.

Evaluation of cytarabine against Ewing sarcoma xenografts by the pediatric preclinical testing program

Treatment with the nucleoside analog cytarabine has been shown to mimic changes in gene expression associated with downregulation of the EWS-FLI1 oncogene in Ewing sarcoma cell lines, selectively inhibit their growth in vitro, and cause tumor regression in athymic nude mice. For this report cytarabine was studied in vitro against a panel of 23 pediatric cancer cell lines and in vivo against 6 Ewing sarcoma xenografts. Acute lymphoblastic leukemia cell lines were the most sensitive to cytarabine in vitro (median IC(50) 9 nM), while Ewing sarcoma cell lines showed intermediate sensitivity (median IC(50) 232 nM). Cytarabine at a dose of 150 mg/kg administered daily 5× failed to significantly inhibit growth of five xenograft models, but reduced growth rate of the A673 xenograft by 50%. Cytarabine shows no differential in vitro activity against Ewing sarcoma cell lines and is ineffective in vivo against Ewing sarcoma xenografts at the dose and schedule studied.

Phase II study of irinotecan and temozolomide in children with relapsed or refractory neuroblastoma: a Children's Oncology Group study

PURPOSE

This phase II study was conducted to determine the response rate associated with use of irinotecan and temozolomide for children with relapsed/refractory neuroblastoma.

PATIENTS AND METHODS

Patients with relapsed/refractory neuroblastoma measurable by cross-sectional imaging (stratum 1) or assessable by bone marrow aspirate/biopsy or metaiodobenzylguanidine (MIBG) scan (stratum 2) received irinotecan (10 mg/m(2)/dose 5 days a week for 2 weeks) and temozolomide (100 mg/m(2)/dose for 5 days) every 3 weeks. Response was assessed after three and six courses using International Neuroblastoma Response Criteria. Of the first 25 evaluable patients on a given stratum, five or more patients with complete or partial responses were required to conclude that further study would be merited.

RESULTS

Fifty-five eligible patients were enrolled. The objective response rate was 15%. Fourteen patients (50%) on stratum 1 and 15 patients (56%) on stratum 2 had stable disease. Objective responses were observed in three of the first 25 evaluable patients on stratum 1 and five of the first 25 evaluable patients on stratum 2. Less than 6% of patients experienced ≥ grade 3 diarrhea. Although neutropenia was observed, less than 10% of patients developed evidence of infection while neutropenic.

CONCLUSION

The combination of irinotecan and temozolomide was well tolerated. The objective response rate of 19% in stratum 2 suggests that this combination may be effective for patients with neuroblastoma detectable by MIBG or marrow analysis. Although fewer objective responses were observed in patients with disease measurable by computed tomography/magnetic resonance imaging, patients in both strata seem to have derived clinical benefit from this therapy.

Targeted Therapy of Ewing's Sarcoma

Refractory and/or recurrent Ewing's sarcoma (EWS) remains a clinical challenge because the disease's resistance to therapy makes it difficult to achieve durable results with standard treatments that include chemotherapy, radiation, and surgery. Recently, insulin-like-growth-factor-1-receptor (IGF1R) antibodies have been shown to have a modest single-agent activity in EWS. Patient selection using biomarkers and understanding response and resistance mechanisms in relation to IGF1R and mammalian target of rapamycin pathways are areas of active research. Since EWS has a unique tumor-specific EWS-FLI1 t(11;22) translocation and oncogenic fusion protein, inhibition of EWS-FLI1 transcription, translation, and/or protein function may be key to eradicating EWS at the stem-cell level. Recently, a small molecule that blocks the protein-protein interaction of EWS-FLI1 with RNA helicase A has been shown in preclinical models to inhibit EWS growth. The successful application of this first-in-class protein-protein inhibitor in the clinic could become a model system for translocation-associated cancers such as EWS.

High-dose cyclophosphamide-irinotecan-vincristine for primary refractory neuroblastoma

BACKGROUND

We used a novel regimen for neuroblastoma (NB) that had responded inadequately to standard chemotherapy which now includes topotecan in induction or second-line therapy.

PATIENTS AND METHODS

We retrospectively studied 38 patients who received one or two courses of high-dose cyclophosphamide (140 mg/kg)-irinotecan (CPT-11) (250 mg/m(2))-vincristine (HD-CCV) as treatment for NB that had responded incompletely to induction but had never progressed. Treatment was outpatient and was preceded and followed by extent-of-disease and toxicity evaluations because the patients were being considered for enrolment on formal protocols. Progression-free survival (PFS) was calculated from day 1 of HD-CCV.

RESULTS

Common toxicities were grade 4 myelosuppression and grade 2 diarrhoea. Responses--5 complete (CR), 3 partial (PR), 4 mixed (MR)--occurred in 12/28 (43%) patients treated ≤9 months, and in 1/10 (10%) patients treated >10 months, from diagnosis. HD-CCV was the initial salvage regimen after topotecan-containing induction in 5 patients, achieving 1 CR, 1 MR and 3 stable disease (NR). HD-CCV produced responses (2 PR, 3 MR) in all 5 patients previously treated with CPT-11/ temozolomide. In contrast, all 6 patients treated post-HD-CCV with CPT-11/temozolomide had NR to the latter. Post-HD-CCV treatments included immunotherapy, targeted radiotherapy and/or chemotherapy. PFS was 64% (±8%) at 24 months, with 20 patients progression-free at 2+-to-36+ (median 16+) months and 10 in first CR at 9+-to-36+ (median 16+) months.

CONCLUSIONS

HD-CCV offers a treatment option against topotecan-resistant NB. Results support the concept that combining CPT-11 with very high doses of alkylators can yield greater antitumour effect.

Phase I study of topotecan in combination with temozolomide (TOTEM) in relapsed or refractory paediatric solid tumours

PURPOSE

To evaluate maximum tolerated dose and recommended dose (RD) for phase II studies of topotecan (TPT) combined with temozolomide (TMZ) (TOTEM) in children and adolescents with relapsed or refractory solid malignancies.

PATIENTS AND METHODS

Multicentre, phase I study with a standard '3+3' design in five dose increments. Eligible patients: aged 6 months to 21 years, diagnosis of a solid malignancy failed at least 2 previous lines of therapy. TMZ was administered orally, starting at 100 mg/m(2)/d, and TPT intravenously over 30 min, starting at 0.75 mg/m(2)/d over 5 consecutive days every 28 d. A pharmacokinetics analysis was performed on Day 1 and Day 5 of cycle 1.

RESULTS

Between February and October 2007, 16 patients were treated. The median age was 8.5 years (range, 3-19 years). Dose-limiting toxicity (grade 4 neutropenia and/or thrombocytopenia lasting more than 7 d) during the first cycle occurred in 2 of 3 patients at level 3 (TMZ 150 mg/m(2)/d and TPT 1.0 mg/m(2)/d) and was always manageable. Confirmed complete and partial responses were observed in 4 patients (25%), three with metastatic neuroblastoma and one with high-grade glioma. Seven patients had a stable disease. Pharmacokinetic data show a wide inter-individual variability. No significant differences were observed between plasma TMZ and TPT concentrations on Day 1 and Day 5 indicating the absence of pharmacokinetic interaction between the drugs.

CONCLUSIONS

The RD for the combination is TMZ 150 mg/m(2)/d and TPT 0.75 mg/m(2)/d with dose-limiting haematological toxicity. The observed activity deserves further evaluation in paediatric malignancies.

Extended phase I evaluation of vincristine, irinotecan, temozolomide, and antibiotic in children with refractory solid tumors

BACKGROUND

The combination of irinotecan, temozolomide, and vincristine is appealing because of potentially synergistic mechanisms of action and non-overlapping toxicities. This phase I study was designed to determine the toxicity and maximum tolerated dose (MTD) of escalating daily protracted doses of irinotecan given in this combination. With extended accrual, we more fully explored the toxicity of multiple courses at the MTD.

PROCEDURE

Patients under 22 years with recurrent or refractory solid tumors were eligible. A course of chemotherapy was given every 28 days. Cefpodoxime was given for diarrhea prophylaxis. Vincristine (1.5 mg/m2, max 2 mg) was given intravenously (IV) on days 1 and 8. Temozolomide (100 mg/m2/day) was given orally on days 1-5. Irinotecan was given IV over 1 hr on days 1-5 and 8-12. Dose escalation was done in the standard 3 + 3 cohort design, starting at 15 mg/m2/day.

RESULTS

Twenty-five of 26 eligible patients were evaluable for toxicity and response. They received 111 courses (1-13, median 4). Dose limiting toxicity (DLT-pancreatitis, transaminitis) was seen in two of three patients at dose level 2 (20 mg/m2). No patients at level 1 had DLT during the first two cycles. Thus, the MTD of irinotecan in this combination is 15 mg/m2/day x 10 doses. Hematologic toxicity was mild and not prolonged. Grade 3 diarrhea was seen in five courses. Responses included two complete and two partial with 12 stable disease (SD) (median 6 months).

CONCLUSIONS

This combination is safe and shows activity in pediatric patients with recurrent malignancy.

Management of adult soft-tissue sarcoma of the extremities and trunk

Soft-tissue sarcomas are a heterogeneous group of tumors consisting of approximately 100 distinct diagnoses. Management requires a multimodality approach with the input of pathologists, surgeons, radiation oncologists, medical oncologists and radiologists. In localized disease, the primary modality of treatment is wide-resection surgery, and the use of radiation therapy has improved local control rates for high-grade tumors. Currently, most localized tumors can be managed with limb-sparing treatment, and local control rates of 80-90% can be seen with appropriate management. Improvements in classification and diagnosis of these tumors have led to the current idea that the specific histology is an important consideration when developing a treatment plan and may affect prognosis, although existing staging systems have not yet incorporated this parameter. Treatment of metastatic disease continues to be difficult, but current research focuses on clarifying molecular mechanisms of disease and identifying new potential targets for medical therapy. This review focuses on the current status of management of these tumors including a review of epidemiology, initial evaluation, and treatment including surgical, radiation, and medical aspects.

Phase I trial of two schedules of vincristine, oral irinotecan, and temozolomide (VOIT) for children with relapsed or refractory solid tumors: a Children's Oncology Group phase I consortium study

BACKGROUND

In preclinical models, temozolomide, and vincristine are additive or synergistic with irinotecan. We examined this three-drug combination in children with relapsed solid tumors. Patients received orally administered irinotecan together with temozolomide and vincristine on two different schedules, using cefixime to reduce irinotecan-associated diarrhea.

METHODS

Oral irinotecan was given daily on days 1-5 and 8-12 (Schedule A), or on days 1-5 (Schedule B). Temozolomide was given on days 1-5, with vincristine 1.5 mg/m(2) administered on days 1 and 8 (Schedule A) or day 1 (Schedule B) in 21-day courses.

RESULTS

On Schedule A, the maximum tolerated dose of oral irinotecan was 35 mg/m(2)/day combined with temozolomide 100 mg/m(2)/day and vincristine on days 1 and 8. Dose-limiting toxicities in 4 of 12 patients included hepatotoxicity, abdominal pain, anorexia, hypokalemia, and thrombocytopenia at 50 mg/m(2)/day. Using Schedule B, 0 of 6 patients experienced dose-limiting toxicity (DLT) at the highest doses studied of oral irinotecan 90 mg/m(2)/day, temozolomide 150 mg/m(2)/day x 5, and vincristine on day 1. First-course and cumulative toxicity was greater with Schedule A. UGT1A1*28 genotype did not correlate with DLT. At the irinotecan dose of 90 mg/m(2)/day, the mean SN-38 AUC(inf) was 63 ng/ml hr. Activity was seen in sarcoma patients, and overall eight patients received >or=6 courses.

CONCLUSIONS

The 5-day schedule of VOIT was well tolerated and provided SN-38 exposures similar to those achieved with intravenous IRN. Activity on this and prior studies suggests a potential role for VOIT in a spectrum of childhood solid tumors.