Effect of fractionated ifosfamide on the pharmacokinetics of irinotecan in pediatric patients with osteosarcoma

A Chart Review on the Feasibility and Safety of the Vincristine Irinotecan Pazopanib (VIPaz) Association in Children and Adolescents With Resistant or Relapsed Sarcomas

Background: Pediatric patients with relapsed or refractory sarcomas have poor outcome and need novel therapies that provide disease control while maintaining an acceptable quality of life. The safety of vincristine, irinotecan, and pazopanib (VIPaz) association has not yet been published in this population. Methods: A chart review was conducted in children and adolescents with relapsed or refractory bone and soft tissue sarcomas who received VIPaz in our institution. Results: One hundred sixty-six patients with a diagnosis of soft or bone sarcoma were admitted to our hospital in the period between March 2015 and August 2018, 30 were relapsed or resistant. Seventeen out of 30 resistant or relapsed patients (median age, 14 years) received 114 VIPaz cycles (median six cycles per patient, range 1-17). Sixteen courses (15%) resulted in gastrointestinal toxicity with Grade two diarrhea; 35 courses (30%) resulted in Grade ≥3 neutropenia. One patient presented Grade two hypothyroidism after nine courses, and another one had Grade two hyperbilirubinemia after 12 courses. Two and five patients required a 25% dose reduction of irinotecan (because of diarrhea) and pazopanib (because of neutropenia four and hyperbilirubinemia 1), respectively. No patient experienced heart failure, hypertension, nor posterior reversible encephalopathy syndrome. Pneumothorax was not reported in any case even in lung metastatic patients. After two and four VIPaz cycles, we observed one complete response (CR), five partial responses (PRs), seven stable diseases (SDs), and four progressive diseases (PDs). With a median follow-up of 15 months (range 3-32), five out of 17 (29%) patients were alive, and four patients were in continuous CR after 12 VIPaz cycles. Conclusions: The VIPaz regimen might be a safe option in children and adolescents with relapsed or refractory sarcomas otherwise unable to be enrolled in other clinical trials; on the other hand, the efficacy of pazopanib observed cannot be sustained from the current study.

ATF6α Activation Enhances Survival against Chemotherapy and Serves as a Prognostic Indicator in Osteosarcoma

Patients with metastatic or relapsed/refractory osteosarcoma (OS) have a 5-year survival rate of <30%. This has remained unchanged over several decades. One of the factors contributing to lack of improvement in survival is the development of chemoresistance. Hence, elucidating and targeting the mechanisms that promote survival against chemotherapy and lead to chemoresistance is pivotal to improving outcomes for these patients. We identified that endoplasmic reticulum (ER) stress-activated transcription factor, ATF6α, is essential for the survival of OS cells against chemotherapy induced cell death. ATF6α cleavage and activity were enhanced in OS cells compared to normal osteoblasts and knockdown of ATF6α expression enhanced sensitivity of OS cells against chemotherapy induced cell death. This was in part due to increased Bax activation. Pharmacologic inhibition or knock-down of downstream targets of ATF6α, protein disulfide isomerases (PDI) and ERO1β, a thiol oxidase that is involved in the re-oxidation of PDIs also independently induced pronounced killing of OS cells following chemotherapy. Analysis of primary tumors from OS patients reveals that patients with high levels of nuclear ATF6α: (1) also had increased expression of its downstream targets the chaperone BiP and enzyme PDI, (2) had a significant likelihood of developing metastasis at diagnosis, (3) had significantly poorer overall and progression free survival, and (4) had poorer response to chemotherapy. These findings suggest that targeting survival signaling by the ATF6α pathway in OS cells may favor eradication of refractory OS tumor cells and ATF6α could be a useful predictor for chemo-responsiveness and prognosis.

Docetaxel, bevacizumab, and gemcitabine for very high risk sarcomas in adolescents and young adults: A single-center experience

BACKGROUND

Adolescent and young adult (AYA) patients with very high risk sarcomas have poor outcomes and are in need of novel therapies.

PROCEDURE

From January 2005 to February 2016, we retrospectively identified all AYA patients with relapsed or metastatic high-grade sarcomas, who were treated with at least one cycle of docetaxel (T), bevacizumab (A), and gemcitabine (G) (TAG ; T = 100 mg/m² Day 8, A = 15 mg/kg Day 1, G = 1,000 mg/m² Days 1 and 8).

RESULTS

Fourteen patients, median age of 20 (15-30), received a total of 80 cycles of TAG, and were followed for a median of 83 months. Diagnosis included osteosarcoma (OST; 8), Ewing sarcoma (3), and soft tissue sarcoma (3). Five of 14 patients achieved clinical remission (CR), 3 had partial responses (PR), 3 had stable disease (SD), and 3 had progressive disease (PD). The median progression-free survival and overall survival were 7 and 19 months, respectively. The objective response rate (CR + PR) and tumor control rate (CR + PR + SD) were 57% and 79%, respectively, with two patients alive after 5 years; toxicities included thrombocytopenia, neutropenia, and capillary leak syndrome.

CONCLUSIONS

Our study builds on previous studies utilizing TAG in adult leiomyosarcoma (LMS) by focusing on AYA, non-LMS sarcomas, especially OST. Our experience suggests that TAG is well tolerated and has activity in very high risk sarcomas in AYA.

Continuous-infusion ifosfamide and doxorubicin combination as second-line chemotherapy for recurrent or refractory osteosarcoma patients in China: a retrospective study

OBJECTIVE

The aim of this retrospective study was to evaluate the feasibility and efficacy of response to continuous-infusion ifosfamide and doxorubicin combination as second-line chemotherapy for patients with recurrent or refractory osteosarcoma.

MATERIALS AND METHODS

Eighteen recurrent or refractory osteosarcoma patients who were treated with continuous-infusion ifosfamide and doxorubicin combination between May 1999 and April 2011 were included in the analysis. Ifosfamide at 12 g/m2 was administered by intravenous continuous infusion over 3 days, and doxorubicin 60 mg/m2 was administered as an intravenous bolus injection on day 1. The combination therapy was repeated every 3 weeks. Treatment was continued until evidence of disease progression or unacceptable toxicity.

RESULTS

The patients (ages 7-53 years) received a total of 42 cycles of chemotherapy (median: 2 courses; range: 2-5 courses). The overall response rate was 0% and the disease control rate was 22.3%, with four patients having stable disease. The median time to progression and overall survival time were 2 months (range: 2-5 months) and 9 months (range: 3-29 months), respectively. Major severe toxicities were leucopenia 7 (38.9%), nausea and vomiting 3 (16.7%) and alopecia 9 (50%). There were no treatment-related deaths.

CONCLUSIONS

In our experience, continuous-infusion ifosfamide and doxorubicin combination therapy at this dosage and schedule was found to be well tolerated and moderate effective, which could be considered as salvage therapy for patients with recurrent or refractory osteosarcoma. Further assessment is necessary to confirm the safety and efficacy of this treatment.

Fifteen years of irinotecan therapy for pediatric sarcoma: where to next?

Over the past 15 years, irinotecan has emerged as an important agent for treating pediatric sarcoma patients. This review summarizes the activity noted in previous studies, and outlines current issues regarding scheduling, route of administration, and amelioration of side effects. Also discussed are new pegylated and nanoliposomal formulations of irinotecan and its active metabolite, SN-38, as well as future plans for how irinotecan may be used in combination with other conventional cytotoxic as well as targeted agents.

Comparison of pemetrexed plus cisplatin with gemcitabine plus docetaxel in refractory/metastatic osteosarcoma: Clinical outcomes from a retrospective database monitored in a single institute

The prognosis for patients with relapsed/metastatic osteosarcoma is poor and the optimal treatment strategy remains to be refined. Whilst gemcitabine plus docetaxel combination treatment has already been demonstrated to have certain promising results in the treatment of osteosarcoma, the use of pemetrexed, a multi-targeted antifolate, remains controversial. In the present study, a retrospective investigation was conducted to evaluate the toxicity and efficacy of the pemetrexed plus cisplatin combination in relapsed/metastatic osteosarcoma. Comparison of this treatment with that of the gemcitabine plus docetaxel combination was also conducted. Clinical data from 39 patients suffering from refractory/metastatic osteosarcoma between January 2005 and May 2011 were reviewed retrospectively. Of these patients, 21 were administered the gemcitabine plus docetaxel combination, and 18 were provided the pemetrexed plus cisplatin combination. Treatment was continued until the occurrence of disease progression or unacceptable toxicity. In the gemcitabine plus docetaxel group, the overall response rate and disease control rate were found to be 9.5 and 28.5% respectively, compared with 5.5 and 33.3% respectively in the pemetrexed plus cisplatin group. The median progression-free survival (PFS) time was found to be 1.8 months for both the gemcitabine plus docetaxel and pemetrexed plus cisplatin groups. The median overall survival (OS) time was 6 months in the gemcitabine plus docetaxel group and 7 months in the pemetrexed plus cisplatin group. No statistically significant differences were recognized between the overall response rates, disease control rates, PFS times and OS times in the two groups. The two combinations appeared to be well tolerated. However, the incidence of grade 3/4 thrombocytopenia and leucopenia was higher in the gemcitabine plus docetaxel group than in the pemetrexed plus cisplatin group. The present study clearly demonstrated that both chemo-combinations were well-tolerated and exerted antitumor activity in patients with refractory/metastatic osteosarcoma. However, with regard to grade 3/4 toxicity, the pemetrexed plus cisplatin chemotherapy appears to be better tolerated.

Evaluation of pirarubicin-cisplatin chemotherapy in the treatment for refractory and recurrent high-grade osteosarcoma: experience of a single institute

The purpose of this study was to investigate the feasibility and efficacy of pirarubicin (THP)-cisplatin (DDP) chemotherapy for refractory and recurrent high-grade osteosarcoma. Between 2008 and 2010, 23 patients with refractory and recurrent high-grade osteosarcoma were included in this analysis. THP was given at a dose of 50 mg/m(2) i.v. d1 and DDP 100-120 mg/m(2) i.v. d2-3 every 3 weeks. Treatment was continued until evidence of disease progression or unacceptable toxicity. Tumor response was usually evaluated every two chemotherapy cycles by CT/MRI scan. The primary end point was overall response rate, secondary endpoint including progression-free survival (PFS), overall survival (OS), disease control rate, and toxicities. A total of 68 cycles were given, median 2 per patient (range 2-7). Overall response rate was 13% and disease control rate was 34.5%, with 3 partial responses and 5 stable diseases. Median time to progression and overall survival time were 2 (95%CI 2-11) and 10 months (95%CI 6-23), respectively. Major severe toxicities were grade 3 or 4 leucopenia occurred 12 times (17.7%) in total cycles; Mild toxicities included grade 1 or 2 nausea and vomiting (80.9%), leucopenia (61.8%), fatigue (50.0%), and alopecia (79.4%). THP-DDP regimen chemotherapy represents an active and well-tolerated treatment for Chinese refractory and recurrent high-grade osteosarcoma patients. Further assessment is necessary to confirm the safety and efficacy of this treatment.

Phase 2 trial of two courses of cyclophosphamide and etoposide for relapsed high-risk osteosarcoma patients

BACKGROUND

A phase 2 trial was carried out to assess the antineoplastic activity of 2 courses of cyclophosphamide-etoposide in relapsed osteosarcoma patients.

METHODS

Twenty-six relapsed osteosarcoma patients with a median age of 18.5 years (8.3-47.1) were enrolled. Seven patients were in first relapse (27%), 11 in second relapse (42%), 7 in third relapse (27%), and 1 in fourth relapse (4%). Eighteen patients had bone metastasis at study entry (69%). Cyclophosphamide was given at 4 g/m(2) on Day 1 followed by etoposide at 200 mg/m(2) on Days 2, 3, and 4. Second cyclophosphamide and etoposide was planned at 21 days to 28 days from the previous one. The primary endpoint of the study was the clinical benefit at 4 months measured as progression-free survival.

RESULTS

Progression-free survival at 4 months was 42%. Five patients achieved responses (19%), 9 patients had stable disease (35%), and 12 had tumor progression (46%). Overall survival (OS) at 1 year was 50%. The only grade 4 extrahematological toxicities were fever (5%), acute bronchospasm (4%) and stomatitis (18%). Six patients (23%) underwent radical surgery after cyclophosphamide and etoposide x2.

CONCLUSIONS

Cyclophosphamide and etoposide x2 may arrest osteosarcoma progression in a significant number of patients (54%). Osteosarcoma progression arrest after cyclophosphamide and etoposide x2 translates in a better OS. Cyclophosphamide and etoposide x2 had good tolerability and the toxicity was time-limited and resolved in all cases.

UGT1A1 promoter genotype correlates with SN-38 pharmacokinetics, but not severe toxicity in patients receiving low-dose irinotecan

PURPOSE

To study the association between UDP-glucuronosyltransferase 1A1 (UGT1A1) genotypes and severe toxicity as well as irinotecan disposition in pediatric patients with solid tumors receiving low-dose, protracted irinotecan (15 to 75 mg/m2 daily for 5 days for 2 consecutive weeks).

PATIENTS AND METHODS

Seventy-four patients on five institutional clinical trials received irinotecan (15 to 75 mg/m2) daily intravenously or orally for 5 days for 2 consecutive weeks. Genomic DNA was genotyped for UGT1A1*28, and patients were designated as 6/6, 6/7, or 7/7 depending on the number of TA repeats in the UGT1A1 promoter region. Patients were evaluated for gastrointestinal and hematologic toxicity, as well as baseline and maximal serum bilirubin levels. Toxicity and pharmacokinetic results were evaluated during courses 1 and 2 of irinotecan therapy.

RESULTS

The frequencies of 6/6, 6/7, and 7/7 genotypes were 27 (36.5%), 36 (48.6%), and 9 (12.2%) of 74 patients, respectively. Patients with 7/7 genotype had a statistically greater baseline total bilirubin than patients with 6/6 or 6/7 genotype (P = .005). UGT1A1*28 genotype was not associated with grade 3 and 4 neutropenia (P = .21 for course 1; P = .23 for course 2) or diarrhea (P = .176 for course 1; P = .87 for course 2). However, patients with the 7/7 genotype tended to have higher SN-38 area under the plasma time-concentration curve (AUC) values and lower SN-38G/SN-38 AUC ratios.

CONCLUSION

Severe toxicity was not increased in pediatric patients with the 7/7 genotype when treated with a low-dose protracted schedule of irinotecan. Therefore, UGT1A1 genotyping is not a useful prognostic indicator of severe toxicity for patients treated with this irinotecan dosage and schedule.

Telangiectatic osteosarcoma: The St. Jude Children's Research Hospital's experience

BACKGROUND

Telangiectatic osteosarcoma (TOS) is a rare subtype of osteosarcoma (OS). The authors reviewed their experience with TOS to characterize its histologic, radiologic, and clinical features.

METHODS

The authors reviewed records, pathology material, and imaging studies from all patients with TOS who were treated between 1978 and 2005 and compared their outcomes with the outcomes of patients with all other subtypes of high-grade osteosarcoma (OS).

RESULTS

Among 323 patients with OS, 22 patients (6.8%) had TOS. Two additional patients who were treated in Chile on a recent OS trial were included. The median age at diagnosis of the 24 patients was 15.7 years. Four patients (17%) had metastatic disease, and 9 of 21 patients (43%) had pathologic fractures. Only 5 patients (who were treated after 1994) underwent limb-salvage surgery. Estimates of 5-year event-free survival (58.3% +/- 11.9%) and overall survival (66.8% +/- 11.6%) were similar to those for patients with other OS subtypes (P > or = .85). The absence of local disease progression and chemotherapy with > or =3 agents that were active against OS were correlated with improved outcome (P < or = .005). The presence of a pathologic fracture was not associated with surgery type or patient outcome.

CONCLUSIONS

TOS was associated with a high rate of pathologic fracture. With multimodality therapy, the outcome of patients with TOS was similar to that of patients with other high-grade OS subtypes. The absence of local disease progression and chemotherapy with > or =3 active agents were associated with a favorable outcome.

Metabolism and transport of oxazaphosphorines and the clinical implications

The oxazaphosphorines including cyclophosphamide (CPA), ifosfamide (IFO), and trofosfamide represent an important group of therapeutic agents due to their substantial antitumor and immuno-modulating activity. CPA is widely used as an anticancer drug, an immunosuppressant, and for the mobilization of hematopoetic progenitor cells from the bone marrow into peripheral blood prior to bone marrow transplantation for aplastic anemia, leukemia, and other malignancies. New oxazaphosphorines derivatives have been developed in an attempt to improve selectivity and response with reduced toxicity. These derivatives include mafosfamide (NSC 345842), glufosfamide (D19575, beta-D-glucosylisophosphoramide mustard), NSC 612567 (aldophosphamide perhydrothiazine), and NSC 613060 (aldophosphamide thiazolidine). This review highlights the metabolism and transport of these oxazaphosphorines (mainly CPA and IFO, as these two oxazaphosphorine drugs are the most widely used alkylating agents) and the clinical implications. Both CPA and IFO are prodrugs that require activation by hepatic cytochrome P450 (CYP)-catalyzed 4-hydroxylation, yielding cytotoxic nitrogen mustards capable of reacting with DNA molecules to form crosslinks and lead to cell apoptosis and/or necrosis. Such prodrug activation can be enhanced within tumor cells by the CYP-based gene directed-enzyme prodrug therapy (GDEPT) approach. However, those newly synthesized oxazaphosphorine derivatives such as glufosfamide, NSC 612567 and NSC 613060, do not need hepatic activation. They are activated through other enzymatic and/or non-enzymatic pathways. For example, both NSC 612567 and NSC 613060 can be activated by plain phosphodiesterase (PDEs) in plasma and other tissues or by the high-affinity nuclear 3'-5' exonucleases associated with DNA polymerases, such as DNA polymerases and epsilon. The alternative CYP-catalyzed inactivation pathway by N-dechloroethylation generates the neurotoxic and nephrotoxic byproduct chloroacetaldehyde (CAA). Various aldehyde dehydrogenases (ALDHs) and glutathione S-transferases (GSTs) are involved in the detoxification of oxazaphosphorine metabolites. The metabolism of oxazaphosphorines is auto-inducible, with the activation of the orphan nuclear receptor pregnane X receptor (PXR) being the major mechanism. Oxazaphosphorine metabolism is affected by a number of factors associated with the drugs (e.g., dosage, route of administration, chirality, and drug combination) and patients (e.g., age, gender, renal and hepatic function). Several drug transporters, such as breast cancer resistance protein (BCRP), multidrug resistance associated proteins (MRP1, MRP2, and MRP4) are involved in the active uptake and efflux of parental oxazaphosphorines, their cytotoxic mustards and conjugates in hepatocytes and tumor cells. Oxazaphosphorine metabolism and transport have a major impact on pharmacokinetic variability, pharmacokinetic-pharmacodynamic relationship, toxicity, resistance, and drug interactions since the drug-metabolizing enzymes and drug transporters involved are key determinants of the pharmacokinetics and pharmacodynamics of oxazaphosphorines. A better understanding of the factors that affect the metabolism and transport of oxazaphosphorines is important for their optional use in cancer chemotherapy.