Continuous 5-day infusion of ifosfamide with mesna in inoperable pancreatic cancer patients: a phase II study

Encapsulated cells expressing a chemotherapeutic activating enzyme allow the targeting of subtoxic chemotherapy and are safe and efficacious: data from two clinical trials in pancreatic cancer

Despite progress in the treatment of pancreatic cancer, there is still a need for improved therapies. In this manuscript, we report clinical experience with a new therapy for the treatment of pancreatic cancer involving the implantation of encapsulated cells over-expressing a cytochrome P450 enzyme followed by subsequent low-dose ifosfamide administrations as a means to target activated ifosfamide to the tumor. The safety and efficacy of the angiographic instillation of encapsulated allogeneic cells overexpressing cytochrome P450 in combination with low-dose systemic ifosfamide administration has now been evaluated in 27 patients in total. These patients were successfully treated in four centers by three different interventional radiologists, arguing strongly that the treatment can be successfully used in different centers. The safety of the intra-arterial delivery of the capsules and the lack of evidence that the patients developed an inflammatory or immune response to the encapsulated cells or encapsulation material was shown in all 27 patients. The ifosfamide dose of 1 g/m²/day used in the first trial was well tolerated by all patients. In contrast, the ifosfamide dose of 2 g/m²/day used in the second trial was poorly tolerated in most patients. Since the median survival in the first trial was 40 weeks and only 33 weeks in the second trial, this strongly suggests that there is no survival benefit to increasing the dose of ifosfamide, and indeed, a lower dose is beneficial for quality of life and the lack of side effects. This is supported by the one-year survival rate in the first trial being 38%, whilst that in the second trial was only 23%. However, taking the data from both trials together, a total of nine of the 27 patients were alive after one year, and two of these nine patients were alive for two years or more.

Evaluation of a gene-directed enzyme-product therapy (GDEPT) in human pancreatic tumor cells and their use as in vivo models for pancreatic cancer

Background

Gene-directed enzyme prodrug therapy (GDEPT) is a two-step treatment protocol for solid tumors that involves the transfer of a gene encoding a prodrug-activating enzyme followed by administration of the inactive prodrug that is subsequently activated by the enzyme to its tumor toxic form. However, the establishment of such novel treatment regimes to combat pancreatic cancer requires defined and robust animal model systems.

Methods

Here, we comprehensively compared six human pancreatic cancer cell lines (PaCa-44, PANC-1, MIA PaCa-2, Hs-766T, Capan-2, and BxPc-3) in subcutaneous and orthotopical mouse models as well as in their susceptibility to different GDEPTs.

Results

Tumor uptake was 83% to 100% in the subcutaneous model and 60% to 100% in the orthotopical mouse model, except for Hs-766T cells, which did not grow orthotopically. Pathohistological analyses of the orthotopical models revealed an infiltrative growth of almost all tumors into the pancreas; however, the different cell lines gave rise to tumors with different morphological characteristics. All of the resultant tumors were positive for MUC-1 staining indicating their origin from glandular or ductal epithelium, but revealed scattered pan-cytokeratin staining. Transfer of the cytochrome P450 and cytosine deaminase suicide gene, respectively, into the pancreatic cancer cell lines using retroviral vector technology revealed high level infectibility of these cell lines and allowed the analysis of the sensitivity of these cells to the chemotherapeutic drugs ifosfamide and 5-fluorocytosine, respectively.

Conclusion

These data qualify the cell lines as part of valuable in vitro and in vivo models for the use in defined preclinical studies for pancreas tumor therapy.

Assessing treatment effect in pancreatic cancer

CONTEXT

Pancreatic cancer is one of the most deadly forms of cancer (43,140 new cases per year; 36,800 deaths), and most people with pancreatic cancer do not survive past 5 years. New therapeutic regimens are constantly being evaluated in an attempt to reduce the rapid progression of this disease. Although some patients receive neoadjuvant therapy in an attempt to make a nonresectable or borderline-resectable tumor resectable, more patients with resectable disease are being enrolled in clinical trials that provide neoadjuvant therapy. This means more pancreatic resections must be evaluated for therapy effect. Histologic grading schemes for the assessment of posttherapy response have been described, but difficulties associated with determining the histologic features of treatment effect in pancreatic cancer have not been addressed.

OBJECTIVES

To critically review the diagnostic criteria for proposed grading schemes for pancreatic cancer treated with neoadjuvant chemoradiation therapy and to provide guidance to surgical pathologists who encounter treated pancreatic cancer resections.

DATA SOURCES

Published peer-reviewed literature and the personal experience of the authors.

CONCLUSIONS

Assessment of treatment effect in pancreatic cancer is difficult. Pathologists need to be aware that some histologic features of treatment effect overlap with histologic features seen in untreated pancreatic cancer, such as tumor cell anaplasia, necrosis, and fibrosis. Careful assessment of pancreatic resections, including detailed gross examination and thorough histologic sampling, is important in accurately assessing treatment effect and improving patient outcomes.

Salvage therapy with mitomycin and ifosfamide in patients with gemcitabine-resistant metastatic pancreatic cancer: a phase II trial

BACKGROUND

At the time of upfront treatment failure, over half of the patients with advanced pancreatic cancer are candidates for further treatment.

METHODS

Patients with metastatic gemcitabine-resistant pancreatic cancer were treated with mitomycin 8 mg/m(2) on day 1, ifosfamide 2,500 mg/m(2) and mesna 3,000 mg/m(2) on days 1-3 every 28 days until progressive disease. A positive responder was defined as a patient who was progression free at 6 months from trial enrollment. According to the Fleming design, a sample size of 34 patients was estimated assuming p0 = 0.05 and p1 = 0.20.

RESULTS

Between May 2006 and December 2007, 21 patients (median age 56 years; median Karnofsky performance score 80) were enrolled. One patient died before receiving any treatment. Eighteen patients interrupted chemotherapy due to progressive disease (n = 15), toxicity (n = 2) or refusal (n = 1). Grade >2 toxicity consisted of neutropenia in 80% of patients, thrombocytopenia and fatigue in 20% and anemia in 10%. Only 1 patient was progression free at 6 months (5%). One patient had a partial response (5%) and 2 patients had stable disease (10%). Median survival was 3.7 months.

CONCLUSION

Based on the poor outcome observed and on the high level of grade 3-4 toxicity, the trial was prematurely stopped and the mitomycin and ifosfamide regimen was considered insufficiently active in gemcitabine-pretreated advanced pancreatic cancer.

Fabrication of gold nanoparticles for targeted therapy in pancreatic cancer

The targeted delivery of a drug should result in enhanced therapeutic efficacy with low to minimal side effects. This is a widely accepted concept, but limited in application due to lack of available technologies and process of validation. Biomedical nanotechnology can play an important role in this respect. Biomedical nanotechnology is a burgeoning field with myriads of opportunities and possibilities for advancing medical science and disease treatment. Cancer nanotechnology (1-100 nm size range) is expected to change the very foundations of cancer treatment, diagnosis and detection. Nanomaterials, especially gold nanoparticles (AuNPs) have unique physico-chemical properties, such as ultra small size, large surface area to mass ratio, and high surface reactivity, presence of surface plasmon resonance (SPR) bands, biocompatibility and ease of surface functionalization. In this review, we will discuss how the unique physico-chemical properties of gold nanoparticles may be utilized for targeted drug delivery in pancreatic cancer leading to increased efficacy of traditional chemotherapeutics.

Intra-arterial instillation of microencapsulated, Ifosfamide-activating cells in the pig pancreas for chemotherapeutic targeting

BACKGROUND

The therapeutic efficacy of intratumoral instillation of genetically engineered, CYP2B1-expressing, microencapsulated cells in combination with ifosfamide had been previously demonstrated in xenografted human pancreatic ductal carcinomas [Gene Ther 1998;5:1070-1078]. Prior to a clinical study, the feasibility of an intra-arterial application of microencapsulated cells to the pancreas and its consequences to the organ had to be evaluated.

MATERIAL AND METHODS

Microencapsulated, CYP2B1-producing cells were instilled both in vivo (transfemoral angiographical access) and in vitro (perfusion model) in the splenic lobe of the pig pancreas. In vivo, animals were monitored clinically for 7 days, then treated with ifosfamide and sacrificed. In vitro, ifosfamide was administered intra-arterially.

RESULTS

In all animals, 100 microcapsules could be instilled safely via the femoral route without clinical, biochemical or histological signs of pancreatitis. Histological examination revealed partial obstruction of small arteries by the capsules, without causing any parenchymal damage. In vitro, instillation reduced blood flow by half. Ifosfamide, also in combination with the capsules, did not add any damage to the pancreas.

CONCLUSION

Intra-arterial instillation of microencapsulated cells to the pig pancreas is feasible and safe. Neither pancreatitis, foreign body reactions nor circulatory disturbances were observed. Clinical application of this genetically enhanced chemotherapeutic method seems possible.

A multispecialty approach to the diagnosis and management of pancreatic cancer

This article reviews recent developments in pancreatic cancer research and offers a multispecialty perspective on the diagnosis and management of this challenging disease. Current findings in the molecular biology of the disease and their implications for management are examined, as well as development in diagnostic techniques, including helical computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangio-pancreatography (MRCP), and, particularly, endoscopic ultrasound-guided fine-needle aspiration. Surgical management, the role of adjuvant/neoadjuvant chemoradiation therapy, and the critical importance of accurate preoperative imaging are also addressed in this review. Palliative techniques, including endoscopic stenting for malignant obstructive jaundice and chemotherapy for locally advanced and metastatic disease, are discussed, and results of recent clinical trials in pancreatic cancer are summarized. Finally, future directions for research are identified.

Injection of encapsulated cells producing an ifosfamide-activating cytochrome P450 for targeted chemotherapy to pancreatic tumors

The prognosis of pancreatic cancer is poor, and current medical treatment is mostly ineffective. The aim of this study was to design a new treatment modality in an animal model system. We describe here a novel treatment strategy employing a mouse model system for pancreatic carcinoma. Embryonal kidney epithelial cells were genetically modified to express the cytochrome P450 subenzyme 2B1 under the control of a cytomegalovirus (CMV) immediate early promoter. This CYP2B1 gene converts ifosfamide to its active cytotoxic compounds, phosphoramide mustard, which alkylates DNA, and acrolein, which alkylates proteins. The cells were then encapsulated in a cellulose sulphate formulation and implanted into preestablished tumors derived from a human pancreatic tumor cell line. Intraperitoneal administration of low-dose ifosfamide to tumor bearing mice that received the encapsulated cells results in partial or even complete tumor ablation. Such an in situ chemotherapy strategy utilizing genetically modified cells in an immunoprotected environment may prove useful for solid tumor therapy in man.

CPT-11 in gastrointestinal cancer

Colorectal, gastric and pancreatic cancers are major health problems worldwide. Although surgery is a curative option in 50% of patients with colorectal cancer, it is much less effective in gastric cancer (< 20% of patients) and virtually ineffective in pancreatic cancer. These three cancer types also respond poorly to chemotherapy. CPT-11 (irinotecan), a novel cytotoxic drug, is now available in many countries as a single agent for second-line therapy in metastatic colorectal cancer. The response rate in the pivotal European study of metastatic colorectal cancer patients was 14%, with a median duration of response of 8.5 months. There was also a high rate of disease stabilisation (44%), with a median duration of 4.8 months. Median survival time was 10.4 months. The dose-limiting toxicities (DLT) for CPT-11 are delayed diarrhoea and neutropenia, both of which are schedule dependent and non-cumulative. These encouraging data in second-line therapy support the further study of CPT-11 as first-line therapy for colorectal cancer in combination with other agents. Four Japanese trials of CPT-11 as first- and/or second-line single-agent therapy for advanced gastric cancer report response rates of 18-43%. The median durations for response and survival time in the late phase II trial were 2.3 months and 5.8 months, respectively. These results are in the range of those reported for sequential high-dose methotrexate and 5-fluorouracil (5-FU)/doxorubicin (FAMTX), etoposide/leucovorin/5-FU (ELF) or cisplatin/5-FU therapy in gastric cancer. Data are currently available from five phase II studies of CPT-11 in advanced pancreatic cancer: four Japanese and one European. The response rates ranged from 9 to 19%. The median duration of survival for all treated patients in the European study was 5.2 months. CPT-11 in combination with 5-FU is currently being investigated in Japan, the U.S.A. and Europe in patients with gastrointestinal tumours. CPT-11 is also being evaluated in combination with each of the following agents: oxaliplatin, docetaxel, raltitrexed, etoposide and mitomycin C. Japanese studies of CPT-11 plus cisplatin in patients with gastric cancer have produced response rates of 48-59%. These encouraging data highlight the potential for CPT-11 in combination therapy for gastrointestinal tumours.

High-dose folinic acid and fluorouracil with or without ifosfamide is an inactive combination in advanced pancreatic cancer. A randomized phase II study of the Italian Oncology Group for Clinical Research (G.O.I.R.C.)

The Italian Oncology Group for Clinical Research (GOIRC) randomized 55 naive patients with advanced pancreatic cancer (APC) between intravenous fluorouracil (5FU) 400 mg/m2, days 1-5 and folinic acid (FA) 200 mg/m2, days 1-5 alone, using Machover's schedule, or with FU, FA, and ifosfamide (IFO) 5 g/m2, day 1 and Mesna. In both arms, treatment was repeated every 28 days. Fifty-one patients were evaluable for response. The overall response rate was 6% (3 out of 51), 1 out of 29 (3%) complete response (CR) in the arm with FU plus FA, and 2 out of 22 (9%) partial responses (PR) in the arm with IFO. The duration of response rate was 39, 55, and 74 weeks, respectively. Median survival time was 21 weeks (range, 4-83 weeks) for 5FU/FA and 16 weeks (range, 3-106 weeks) for the FU/FA/IFO arm. Diarrhea, mucositis, and vomiting occurred in the majority of patients. One patient died due to toxicity. The combination of 5FU plus FA failed to demonstrate therapeutic activity in patients with APC and was associated with moderate to severe toxicity that could lower the quality of life of these patients. Ifosfamide did not potentiate the activity of this combination. Neither of these combinations should be considered for treatment of patients with APC.

Intermittent continuous infusion of ifosfamide and 5-fluorouracil in patients with advanced adenocarcinoma of the pancreas

BACKGROUND

In advanced adenocarcinoma of the pancreas treatment with 5-fluorouracil (5-FU) or ifosfamide results in response rates of approximately 20%. Continuous infusion of these drugs is on many grounds theoretically attractive and may therefore offer advantages over bolus or short-term infusion.

PATIENTS AND METHODS

Sixteen patients with advanced adenocarcinoma of the pancreas with progressive measurable disease and no previous chemotherapy entered the study. After implantation of a subcutaneous infusion chamber patients were treated on days 1-12 with ifosfamide (1.0 g/m2/day) and 5-FU (300 mg/m2/day) as a continuous intravenous infusion using a portable infusion pump. Mesna (1.0 g/m2/day) was added as uroprotective agent from day 1-14. Courses were repeated every 4 weeks.

RESULTS

Fifteen of the 16 patients were evaluable for response. One partial response was observed (response rate 7% [95% CI: 0%-32%]). Toxicity occurred in 64% of the courses. Dose limiting toxic effects were grade 3 nausea/vomiting (WHO) in 3 patients, grade 2 mucositis in 1 patient and grade 4 leukopenia in 1 patient.

CONCLUSION

Intermittent continuous infusion with ifosfamide, mesna and 5-FU is feasible on an outpatient basis. Although continuous infusion of ifosfamide may have a more favorable toxicity profile, the combination of 5-FU and ifosfamide in this schedule is no more effective than bolus or short-term infusion.

Ifosfamide treatment as a 10-day continuous intravenous infusion

Experimental and clinical studies on ifosfamide indicate that fractionated treatment regimens have a higher efficacy compared to a single short-term infusion. In addition, protracted continuous infusion, in general, is often less toxic without loss of antitumour activity. To study the toxicity of a 10-day continuous infusion at increasing dosages of ifosfamide and mesna, 24 patients with a variety of advanced cancers (colon 10, pancreas 5, adenocarcinoma with unknown primary 5, and 4 others) received a total of 60 cycles (range 1-6 cycles, median 2) at 3 to 4 week intervals. The ifosfamide and mesna doses ranged from 654 mg m-2 day-1 to 1562 mg m-2 day-1 for a total of ten doses. Twenty-two patients were chemotherapy-naive. Pharmacia-Deltec CADD-1 pumps and Port-a-Cath implantable venous access devices were used. The dose-limiting toxicity was leucopenia without thrombocytopenia. At a dose of 1300 mg m-2 day-1 in 30% of the cycles in 7 patients leucopenia of WHO grades 3 and 4 was observed, while at higher dosages this percentage increased to 73%. Haemoglobin values usually decreased during the infusion with a mean of 1 mmol/l (range 0.3-2.5 mmol/l), frequently with partial or full recovery by the next cycle. The next most disturbing side-effect was fatigue (50% of patients WHO grades 2 and 3), and nausea and vomiting requiring drug treatment in 75% of patients. Renal failure and haematuria did not occur. There were two catheter-related complications: thrombosis (1 patient) and mechanical obstruction (1 patient). One patient developed severe encephalopathy at day 6 (total dose 18 g ifosfamide) with complete recovery after cessation of the infusion. In summary, a tolerable ifosfamide dose using this regimen in this previously largely untreated patient group appears to be 1200-1300 mg m-2 day-1 for 10 days. Fatigue is a frequent complaint and might be explained as a kind of neurotoxicity. The treatment can be administered to outpatients.

Subcutaneous continuous infusion of ifosfamide and cyclophosphamide in ambulatory cancer patients: bioavailability and feasibility

The oxazaphosphorines ifosfamide (IFO) and cyclophosphamide (CTX) are standard alkylating agents. Both drugs show an increased therapeutic index when given as a fractionated dosage over several days. Maximal fractionation is achieved by continuous infusion. We have studied the feasibility and bioavailability of a subcutaneously (s.c.) administered isotonic and neutral (pH 7) solution of IFO (10 h up to 5 days infusion) and CTX (12-24 h infusion) in patients with advanced cancer. A portable disposable gas-driven infusor syringe was used for ambulatory patients. Our results show 90%-100% bioavailability of s.c. IFO and CTX. The isotonic solution of IFO and CTX (pH 7) showed no significant local toxicity (one local infection in 51 cycles) during or after s.c. administration of 33 cycles with IFO and 18 with CTX. Haematotoxicity of both drugs was equal after s.c. and i.v. application. For IFO-treated patients no uro- or neurotoxicity was observed. We conclude that this novel continuous s.c. oxazaphosphorine infusion over a prolonged period is a rational, well-tolerated and economic way of delivering this drug on an outpatient basis.