A simple outpatient treatment with oral ifosfamide and oral etoposide for patients with small cell lung cancer (SCLC)

Ifosfamide - History, efficacy, toxicity and encephalopathy

In this review we trace the passage of fundamental ideas through 20^th century cancer research that began with observations on mustard gas toxicity in World War I. The transmutation of these ideas across scientific and national boundaries, was channeled from chemical carcinogenesis labs in London via Yale and Chicago, then ultimately to the pharmaceutical industry in Bielefeld, Germany. These first efforts to checkmate cancer with chemicals led eventually to the creation of one of the most successful groups of cancer chemotherapeutic drugs, the oxazaphosphorines, first cyclophosphamide (CP) in 1958 and soon thereafter its isomer ifosfamide (IFO). The giant contributions of Professor Sir Alexander Haddow, Dr. Alfred Z. Gilman & Dr. Louis S. Goodman, Dr. George Gomori and Dr. Norbert Brock step by step led to this breakthrough in cancer chemotherapy. A developing understanding of the metabolic disposition of ifosfamide directed efforts to ameliorate its side-effects, in particular, ifosfamide-induced encephalopathy (IIE). This has resulted in several candidates for the encephalopathic metabolite, including 2-chloroacetaldehyde, 2-chloroacetic acid, acrolein, 3-hydroxypropionic acid and S-carboxymethyl-L-cysteine. The pros and cons for each of these, together with other IFO metabolites, are discussed in detail. It is concluded that IFO produces encephalopathy in susceptible patients, but CP does not, by a "perfect storm," involving all of these five metabolites. Methylene blue (MB) administration appears to be generally effective in the prevention and treatment of IIE, in all probability by the inhibition of monoamine oxidase in brain potentiating serotonin levels that modulate the effects of IFO on GABAergic and glutamatergic systems. This review represents the authors' analysis of a large body of published research.

Novel treatment for the management of ifosfamide neurotoxicity: Rationale for the use of methylene blue

Objective. To provide an overview of the proposed pathophysiology of ifosfamide encephalopathy and the role of methylene blue for the treatment and prevention of this toxicity.

Data Source. A Medline search using the terms ‘‘ifosfamide encephalopathy’’ and ‘‘methylene blue’’ was conducted for the period of 1990-2001. The reference lists from retrieved articles were reviewed

Data Extraction. The author reviewed the retrieved material and included animal and pharmacokinetic data related to ifosfamide and the pathophysiology of ifosfamide neurotoxicity. Additionally, preclinical data and case reports describing the clinical use and rationale for methylene blue were included.

Data Synthesis. Encephalopathy is a unique toxicity described with ifosfamide, but not with cyclophosphamide. Ifosfamide undergoes a secondary ‘‘deactivation’’ metabolic pathway to yield dechloroethylated metabolites and chloroacetalde-hyde. Chloroacetaldehyde is a metabolite that contributes to both the nephrotoxicity and neurotoxicity described with ifosfamide. Chloroacetaldehyde (or a dechloroethylated metabolite) may exert neurotoxic effects by one or more of the following mechanisms: (a) direct neurotoxic damage, (b) depletion of central nervous system (CNS) glutathione level, or (c) inhibition of mitochondrial oxidative phosphorylation resulting in impaired fatty acid metabolism. The biochemical derangements described with this acute toxicity appear to mimic a neonatal mitochondrial disorder, for which methylene blue has been used. Methylene blue has been shown to restore and maintain mitochondrial respiration and therefore can be used to correct or prevent acute neurotoxic effects. Methylene blue has been used to treat moderate to severe cases of ifosfamide neurotoxicity and has also been used prophylactically to prevent encephalopathy in high-risk conditions with the use of oral and bolus iv ifosfamide regimens. Methylene blue may be useful in the treatment of grade III or IV neurotoxicity or in those patients with recurrent neurological symptoms associated with ifosfamide administration. The use of prophylactic or concurrent administration of methylene blue with ifosfamide requires further clinical evaluation.

Standard versus Dose-Intensified Chemotherapy with Sequential Reinfusion of Hematopoietic Progenitor Cells in Small Cell Lung Cancer Patients with Favorable Prognosis

PURPOSE

The combination of ifosfamide, carboplatin, and etoposide (ICE) is highly effective in treating small cell lung cancer (SCLC). Myelosuppression resulting in leukopenia and thrombocytopenia is the dose-limiting toxicity.

PATIENTS AND METHODS

This phase 3 study assessed 2-year survival improvement with dose intensification of ICE chemotherapy (ICT) in patients with good-prognosis SCLC. Patients received up to six cycles of ICT with filgrastim-supported sequential reinfusion of peripheral blood progenitor cells every 14 days, or standard ICE (SCT) every 28 days.

RESULTS

Eighty-three patients were randomized to ICT (n = 42) or SCT (n = 41). Median survival was significantly improved with ICT (30.3 mo) versus SCT (18.5 mo; p = 0.001); 2-year survival was 55% for ICT and 39% for SCT (p = 0.151). Time to progression (TTP) was significantly improved, with 15 months for ICT versus 11.1 months for SCT (p = 0.0001). Overall response rates were 100 and 88% for ICT and SCT, respectively (p = 0.0258). SCT was associated with significantly less grade 3 and 4 leukopenia at day 8 (p < 0.0001), less thrombocytopenia at day 14 (p < 0.0001), and more favorable platelet nadir (p < 0.0001). The need for platelet and red blood cell transfusions significantly increased in the ICT group (p < 0.0001). Nonhematologic adverse events in both groups were comparable and mostly grade 1 or 2.

CONCLUSION

Patients receiving ICT with filgrastim achieved significant increases in median survival and TTP despite an increased need for transfusions.

Advances in the systemic treatment of cancers in the elderly

Cancer is a disease of the elderly. More than 50% of all cancers and deaths occur in people over 65 years. Older cancer patients are less likely to be referred to centers or to be given adequate chemotherapy. The elderly are under-represented in Phase I and II trials. Some of this hesitancy to give chemotherapy is related to the increased presence of co-morbid conditions in the elderly. Toxicity is another concern. This review summarizes data from literature on the effectiveness, outcome, and toxicity of chemotherapy in selected tumors. Information is presented on age related effects. In addition, a summary of new agents and biologics is presented that needs to be looked at for age related effects. Some comments are made on the pharmacokinetic impact of physiologic changes in the elderly on chemotherapy drugs. As the world's population ages, we need to include the elderly in trials to get data on age related effects. Most of the information presented shows that effective chemotherapy can be given safely to the elderly and the outcomes and toxicity are equivalent for many of the common solid tumors.

Metabolism and pharmacokinetics of oxazaphosphorines

The 2 most commonly used oxazaphosphorines are cyclophosphamide and ifosfamide, although other bifunctional mustard analogues continue to be investigated. The pharmacology of these agents is determined by their metabolism, since the parent drug is relatively inactive. For cyclophosphamide, elimination of the parent compound is by activation to the 4-hydroxy metabolite, although other minor pathways of inactivation also play a role. Ifosfamide is inactivated to a greater degree by dechloroethylation reactions. More robust assay methods for the 4-hydroxy metabolites may reveal more about the clinical pharmacology of these drugs, but at present the best pharmacodynamic data indicate an inverse relationship between plasma concentration of parent drug and either toxicity or antitumour effect. The metabolism of cyclophosphamide is of particular relevance in the application of high dose chemotherapy. The activation pathway of metabolism is saturable, such that at higher doses (greater than 2 to 4 g/m2) a greater proportion of the drug is eliminated as inactive metabolites. However, both cyclophosphamide and ifosfamide also act to induce their own metabolism. Since most high dose regimens require a continuous infusion or divided doses over several days, saturation of metabolism may be compensated for, in part, by auto-induction. Although a quantitative distinction may be made between the cytochrome P450 isoforms responsible for the activating 4-hydroxylation reaction and those which mediate the dechloroethylation reactions, selective induction of the activation pathway, or inhibition of the inactivating pathway, has not been demonstrated clinically. Mathematical models to describe and predict the relative contributions of saturation and autoinduction to the net activation of cyclophosphamide have been developed. However, these require careful validation and may not be applicable outside the exact regimen in which they were derived. A further complication is the chiral nature of these 2 drugs, with some suggestion that one enantiomer may have a favourable profile of metabolism over the other. That the oxazaphosphorines continue to be the subject of intensive investigation over 30 years after their introduction into clinical practice is partly because of their antitumour activity. Further advances in analytical and molecular pharmacological techniques may further optimise their use and allow rational design of more selective analogues.

Ifosfamide in the elderly: clinical considerations for a better drug management

The therapeutic strategy used for elderly affected by malignant neoplasms should take into account the common variables present in oncological patients, and the specific alteration of the elderly metabolism and their possible morbidity. Ifosfamide is an active drug for various tumors with elevated incidence in the elderly. We analyze the principle criteria in the selection of these patients and the alterations of metabolism which correlates to aging with their consequences on the pharmacokinetics of ifosfamide. Finally, we propose clinical guidelines to optimize the use of ifosfamide in elderly patients affected by malignant tumors.

Chemotherapy for symptom control in recurrent squamous cell carcinoma of the head and neck

BACKGROUND

The role of chemotherapy in patients with recurrent squamous cell carcinomas of the head and neck (SCCHN) is unclear. The aim of this study was to assess the ability of combination chemotherapy to control symptoms in this setting.

PATIENTS AND METHODS

Using a prospectively accrued database all patients referred for chemotherapy with symptomatic relapse following surgery were identified. Objective response was recorded using standard criteria and maximum symptom response was assessed retrospectively from case notes using a published scoring scale.

RESULTS

A total of 57 (median age 56, range 37-85) patients were studied who had received mainly cisplatin/5-fluorouracil combinations. Thirty-seven had previously received radiotherapy. Fifty-two patients had evaluable disease; 18 (35%) had objective responses (14 PRs and 4 CRs). There were a total of 103 symptoms recorded with eight different individual symptoms. Forty-four (43%) symptoms improved on treatment, 52 (50%) were unchanged and 7 (7%) worsened. The number of patients with improvement in the most frequently recorded symptoms were as follows: pain 11/28 (39%), swelling 12/23 (52%) and dysphagia 6/18 (33%). Sixty-seven percent of patients with objective response also had an improvement in their symptoms but a significant proportion (33%) of non-responders had a symptomatic response. Lack of objective response was not correlated with worsening symptoms. Grade 3/4 toxicity was uncommon (6%-17%) and there were no toxic deaths. A majority of patients (82%) experienced either no change or an improvement in performance status.

CONCLUSION

These results demonstrate that chemotherapy improves many of the symptoms associated with recurrent SCCHN, without deterioration in performance status. Symptomatic improvement is more likely if there is evidence of significant tumour shrinkage, but even non-responding patients can benefit.

Oral ifosfamide/mesna versus intravenous ifosfamide/mesna in non-small-cell lung cancer: a randomized phase II trial of the EORTC lung cancer cooperative group

BACKGROUND

Chronic oral administration of anticancer drugs may offer therapeutic advantages.

PATIENTS AND METHODS

A total of 68 patients with advanced non-small-cell lung cancer, not previously treated by chemotherapy, were randomized to receive either ifosfamide given orally (OSI) at a dose of 1 g/day for 14 days every 4 weeks, or as a 1-hour intravenous infusion (IVI) at a dose of 1.6 g/m2/day for 5 days every 4 weeks. According to the route of ifosfamide administration, patients received either mesna i.v. or mesna film-coated tablets for uroprotection.

RESULTS

Eight patients were found to be ineligible for the study and therefore excluded for all analyses. Thirty-three patients received IVI, and 27 patients OSI. One patient randomized to OSI died before treatment was initiated, leaving 59 patients fully evaluable for toxicity. Hematological toxicity was less severe for patients on OSI, but CNS toxicity was reported more frequently on OSI (39%; 12% grade III/IV), than on IVI (15%; 9% grade III/IV), which caused the premature close of the study. Other non-hematological adverse events were of modest clinical significance and comparable in both arms. Forty-nine patients were considered evaluable for response: in the IVI arm, 5 (17%) of the 29 evaluable patients obtained a partial remission, and 7 patients a no change (24%). In the OSI arm, 2 (10%) of the 20 evaluable patients obtained a partial remission, and 11 (52%) a stable disease.

CONCLUSIONS

Both arms have some activity in non-small-cell lung cancer; while OSI was less myelosuppressive than IVI, it was associated with a higher incidence of CNS toxicity. Oral administration of ifosfamide, in the schedule and daily dose tested here cannot be recommended.

Ifosfamide nephrotoxicity: limited influence of metabolism and mode of administration during repeated therapy in paediatrics

This study investigated the relationship between both acute and chronic nephrotoxic effects of ifosfamide (IFO) and its metabolism. 15 paediatric patients (4 girls) were investigated. Each received 6-9 g/m2 IFO over 15 days, repeated every 3 weeks for up to 16 courses. The pharmacokinetics and metabolism of IFO were measured during its administration, either as a continuous 72 h infusion or as three bolus doses of 3 g/m2 on consecutive days. In 8 patients, the metabolism of IFO was investigated during one early course and one late course to determine the magnitude of any changes following repeated administration. Acute measures of renal toxicity were not correlated with any of the IFO pharmacokinetic or metabolic parameters in the same course, whether the drug was administered as a bolus or by continuous infusion. Chronic renal toxicity, determined 1 month (n = 13) or 6 months (n = 8) after treatment, did not correlate with any of the IFO pharmacokinetic or metabolic parameters in any individual course of treatment. The overall degree of nephrotoxicity, however, was correlated with the changes in metabolism between late and early courses (n = 8). There was a negative correlation between the change in area under the curve of the dechloroethylated metabolites of IFO and the overall nephrotoxicity at 1 month or 6 months after treatment (both r2 = 0.66, P = 0.014). The results imply that patients in whom metabolism via dechloroethylation decreases are at a greater risk of chronic nephrotoxicity. This is contrary to the hypothesis that the systemic production of chloroacetaldehyde is the mechanism by which IFO causes nephrotoxicity. The importance of acute and chronic changes in renal function for long-term outcome remains to be determined.

Quality versus quantity of life in the treatment of patients with advanced small-cell lung cancer? A randomized phase III comparison of weekly carboplatin and teniposide versus cisplatin, adriamycin, etoposide alternating with cyclophosphamide, methotrexate, vincristine and lomustine. Swiss Group for Clinical Cancer Research (SAKK)

BACKGROUND

Based on a promising pilot study with weekly carboplatin and teniposide (CBDCA/VM) the Swiss Group for Clinical Cancer Research (SAKK) performed a randomised phase III trial in patients with extensive-disease small-cell lung cancer aimed at the development of an effective palliative treatment with low subjective toxicity.

PATIENTS AND METHODS

From September 1989 to September 1991 patients were randomised to a weekly regimen of CBDCA/VM or to our 'standard chemotherapy' of cisplatin, adriamycin and etoposide alternating with cyclophosphamide, methotrexate, vincristine and lomustine (PAV-CyMOC).

RESULTS

The trial was closed before the planned accrual of 140 evaluable patients due to a significant survival difference shown by an interim analysis. Of the 61 patients 59 were eligible and included in the final analysis. The results achieved with the PAV-CyMOC regimen were significantly better than those observed in patients treated with weekly CBDCA/VM (remission rate of 65% vs. 29%; p = 0.006). The median survival of patients treated with the PAV-CyMOC combination was significantly longer than that of patients receiving weekly CBDCA/VM (260 days vs. 147 days; p = 0.0035). The 1-year survival rate was 30% in the PAV-CyMOC arm compared to 4% in the CBDCA/VM-treated patients. As expected, side effects including myelosuppression, alopecia and mucositis were significantly more pronounced in patients treated with the PAV-CyMOC regimen. No significant difference was found in patient-rated tumor symptoms and general quality-of-life categories.

CONCLUSION

Contrary to our initial expectation that we would achieve similar therapeutic results with less subjective toxicity, in this randomised prospective trial the results achieved by weekly carboplatin and teniposide were significantly inferior in terms of remission rate and survival to those of our 'standard regimen' of cisplatin, adriamycin and etoposide alternating with cyclophosphamide, methotrexate, vincristine and lomustine. The weekly regimen was less toxic than the standard chemotherapy. Whether patients are willing to accept a significant trade-off between quantity and quality of life remains to be evaluated.

Ifosfamide clinical pharmacokinetics

This article reviews the metabolism and pharmacokinetics of ifosfamide and their implications for the cytostatic efficacy and toxicity pattern of this alkylating agent. Ifosfamide is a prodrug that requires biotransformation to become cytotoxic. It is a structural isomer of cyclophosphamide from which it differs only in having the chlorethyl functions on different nitrogen atoms. This causes a considerable change in initial metabolism, although overall metabolism remains the same. Beside the formation of 4-hydroxy-ifosfamide ('activated ifosfamide'), a second pathway with liberation of chloroacetaldehyde exists. Therefore, less activated drug is formed than during cyclophosphamide metabolism. This fact may well explain why higher doses of ifosfamide are required during treatment. Chloroacetaldehyde may account for the adverse effects and therapeutic effects of the parent drug. This metabolite has been associated with central nervous system toxicity during ifosfamide treatment and was shown to deplete intracellular glutathione concentrations. Glutathione depletion may support the activity of alkylating metabolites in tumour cells, thus overcoming the relative resistance of the cells to alkylating agents. Possibly, this mechanism explains the lack of complete cross-resistance between ifosfamide and cyclophosphamide as well as the greater antitumour activity of ifosfamide in some tumours. Urotoxicity of ifosfamide, which was the dose-limiting adverse effect, can be successfully attenuated by the use of mesna. Distinct pharmacokinetic properties of mesna are responsible for the fact that in contrast to other sulphydryl compounds the uroprotective activity of mesna does not imply a loss of therapeutic efficacy.

Treatment evaluation of combined modality therapy: 'what can we obtain today from phase II trials?'

Demonstration of activity is the major goal of Phase II studies. Other end points-duration of response, survival (relapse free in complete responders), progression free interval, changes in performance status and quality of life also provide useful information. From these data a decision to continue or discard a particular therapy can be considered. Various handicaps including variability in response reporting, heterogeneity of patient populations, inadequate reporting of failure patterns, causes of death, performance status changes and quality of life hinder interpretation of Phase II data. Nevertheless, Phase II studies have defined prognostic groups, beneficial changes in performance status and have helped formulate novel management approaches. Targeting particular prognostic groups, investigating dose-intensive regimens with haemopoietic growth-factor support and novel combined-modality approaches have all been generated through Phase II investigations.

Cancer in the elderly

This article reviews geriatric oncology and assesses options for treatment and care of the elderly patient with cancer. The size of the population over 65 years old is defined, with particular reference to the continuing growth of this subsection of the community. The high incidence of many cancers and their associated mortality rates in the elderly are identified and the epidemiology of such diseases in the geriatric population is addressed. Given the discrepancies in incidence and survival rates between patients younger and older than 65 years, the association between tumorigenesis and the aging process is explored. Specific aspects of tumor growth in the elderly are considered. General considerations of therapy for elderly patients with cancer are discussed, including the pharmacokinetics and pharmacodynamics of chemotherapy in those over 65 years old, surgical options, the use of radiotherapy, and overall patient assessment. Next, treatment options for individual cancer states are reviewed, with particular emphasis on newer treatment options designed specifically for the elderly. Sections on cancer screening and supportive care are also included, the latter dealing with aspects of symptom control, quality of life assessment, and the physical and psychologic rehabilitation of the elderly patient with cancer who is undergoing treatment. Conclusions are then drawn as to the extent of the oncological process in those over 65 years old, with particular emphasis on the underdiagnosis and undertreatment of many malignancies in the past. The challenge created by the growing elderly population is underscored and necessary plans of action for oncologists in the future are defined. Such proposals are necessary if inroads are to be made into the unacceptable morbidity and mortality rates borne by our elderly patients with cancer.

Predicting septic complications of chemotherapy: an analysis of 382 patients treated for small cell lung cancer without dose reduction after major sepsis

The incidence and risk of septic complications in 382 patients treated for small cell lung cancer with combination chemotherapy at a single centre have been analysed. Full protocol doses were employed throughout with no dose reduction after episodes of severe or life-threatening sepsis (SLTS). 50 (13%) patients experienced 66 episodes of SLTS associated with 1978 cycles of chemotherapy (3.2% cycles affected). 20 (5.2%) patients died due to sepsis (SD) of whom only 4 had experienced SLTS with a previous cycle of treatment. The others died as a result of their first septic episode. A model comprising four variables, age (< or = 50 or > 50 years), Karnofsky performance status (KP < or = 50 or > 50), treatment (two- or three-drug regimen) and previous sepsis (SLTS or no SLTS with previous cycles) was found to satisfactorily describe the incidence of SLTS and SD in the study population and once validated in another patient groups this model should allow identification of high-risk individuals before treatment starts. If so, we propose that high-risk patients (age > 50 years, KP < or = 50, treatment with three-drug regimen) receive 50% of protocol doses in the first cycle of treatment with escalation to 75% and eventually 100% doses in subsequent cycles if sepsis does not supervene. Those with one or two risk factors present run a relatively low risk of SLTS or SD and we consider that full-dose chemotherapy should be used throughout in these individuals.

Oral ifosfamide-mesna: a clinical investigation in advanced non-small-cell lung cancer

The purpose of this study was to evaluate the toxicity and response efficacy of fixed-dose oral ifosfamide (OI)-mesna (M) in advanced, non-small-cell lung cancer (NSCLC). OI was given in four different fractionated-dose treatment schedules with a total dose per cycle of either 3.0 g/m2, 6.0 g/m2, 7.5 g/m2 or 10 g/m2 (equivalent to a daily dose of either 750 mg, 1000 mg or 1250 mg.) M was given p.o. by drinking ampules. In the 64 patients (pts) included, a total of 305 treatment cycles were administered with no evidence of severe neurotoxicity. Twenty-two pts (37%) developed mild to moderate CNS toxicity. Neither myelosuppression, alopecia, gastrointestinal toxicity nor urotoxicity were clinical problems. On schedule 2 (6 g/m2), 3 of 14 evaluable pts (21%) had partial remissions (PR), and on schedule 3 (7.5 g/m2) 4 pts (25%) showed PRs. The median duration of response was 9 months (mts) for pts on schedule 2, and 8 mts for pts on schedule 3. We conclude that OIM can easily be tolerated in the same dose usually given intravenously (7.5 g/m2/mts), when patients at high risk for developing CNS toxicity have been previously excluded from therapy. In order to reduce CNS toxicity, it is suggested that the total dose per cycle should not exceed 7.5 g/m2 (1000 mg daily) within a fractionated-dose, 14-day treatment schedule. We further conclude that the tumor response efficacy of OIM in NSCLC is comparable to the one achieved by intravenously-administered IM, whereby the total monthly OI dose should not be less than 6.0 g/m2 (750 mg daily).

Ifosfamide/mesna. A review of its antineoplastic activity, pharmacokinetic properties and therapeutic efficacy in cancer

Ifosfamide is an oxazaphosphorine alkylating agent with a broad spectrum of antineoplastic activity. It is a prodrug metabolised in the liver by cytochrome P450 mixed-function oxidase enzymes to isofosforamide mustard, the active alkylating compound. Mesna, a uroprotective thiol agent, is routinely administered concomitantly with ifosfamide, and has almost eliminated ifosfamide-induced haemorrhagic cystitis and has reduced nephron toxicity. Therapeutic studies, mostly noncomparative in nature, have demonstrated the efficacy of ifosfamide/mesna alone, or more commonly as a component of combination regimens, in a variety of cancers. In patients with relapsed or refractory disseminated nonseminomatous testicular cancer, a salvage regimen of ifosfamide/mesna, cisplatin and either etoposide or vinblastine produced complete response in approximately one-quarter of patients. As a component of both induction and salvage chemotherapeutic regimens, ifosfamide/mesna has produced favourable response rates in small cell lung cancer, paediatric solid tumours, non-Hodgkin's and Hodgkin's lymphoma, and ovarian cancer. Induction therapy with ifosfamide/mesna-containing chemotherapeutic regimens has been encouraging in non-small cell lung cancer, adult soft-tissue sarcomas, and as neoadjuvant therapy in advanced cervical cancer. As salvage therapy, ifosfamide/mesna-containing combinations have a palliative role in advanced breast cancer and advanced cervical cancer. Ifosfamide/mesna can elicit responses in patients refractory to numerous other antineoplastic drugs, including cyclophosphamide. With administration of concomitant mesna to protect against ifosfamide-induced urotoxicity, the principal dose-limiting toxicity of ifosfamide is myelosuppression; leucopenia is generally more severe than thrombocytopenia. Reversible CNS adverse effects ranging from mild somnolence and confusion to severe encephalopathy and coma can occur in approximately 10 to 20% of patients after intravenous infusion, and the incidence of neurotoxicity may be increased to 50% after oral administration because of differences in the preferential route of metabolism between the 2 routes of administration. Other adverse effects of ifosfamide include nephrotoxicity, alopecia, and nausea/vomiting. In general, intravenously administered mesna is associated with a low incidence of adverse effects; however, gastrointestinal disturbances are common following oral administration. Thus, ifosfamide/mesna is an important and worthwhile addition to the currently available range of chemotherapeutic agents. It has a broad spectrum of antineoplastic activity and causes less marked myelosuppression than many other cytotoxic agents. At present, the role of ifosfamide/mesna in refractory germ cell testicular cancer is clearly defined; however, its overall place in the treatment of other forms of cancer awaits delineation in future well-controlled comparative studies.

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

Phase II studies on ifosfamide and mesna in pancreatic cancer have mostly been inconclusive. In all of these studies ifosfamide was administered as an i.v. bolus or by short infusions. Since dose fractionation of ifosfamide over several days increases its therapeutic index, we chose to maximize the dose fractioning by selecting a continuous-infusion schedule (1.75 g/m2 on days 1-5 every 21-28 days, with mesna 60%-100% of the ifosfamide dose up to 12 h after ifosfamide). Since 1987 29 patients (performance status less than or equal to 2) with advanced inoperable adenocarcinoma of the pancreas were studied (8 women and 21 men; median age 58 years: 36-73 years). A total of 25 patients are evaluable for response (1 ineligible; 3 inevaluable: 2 early deaths due to disseminated intravascular coagulation, 1 refusal). One female patient with a complete response on computed tomography scan (after five cycles) but residual liver metastases on surgical exploration survived for 473 days. Three male patients with partial response survived for 205, 335 and 355 days. Six more patients with minor response (3) or no change (3) but significant decrease of tumour marker CA 19-9 had a median survival of 213 days (106-243). Responders seemed to benefit in terms of pain relief and general well-being. The median overall survival of all patients was 148 days (21-473). Haematotoxicity was rarely dose-limiting [median nadirs: white blood cells = 2.1 x 10(9)/l (0.45-6.4), Hb = 10.7 g/dl (7.5-13), platelets = 137 x 10(9)/l (21-411)]. Nausea and vomiting were mild with prophylactic oral metoclopramide. No central nervous system toxicity or urotoxicity was observed. Alopecia was seen in all patients who had received at least two cycles. Continuous infusion of ifosfamide was generally well tolerated and useful for palliation in 10 of 25 patients. A higher dose intensity is recommended.

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.

Bioavailability of subcutaneous ifosfamide and feasibility of continuous outpatient application in cancer patients

The oxazaphosphorine prodrug Ifosfamide (IFO) in conjunction with the uroprotective agent Mesna is becoming a standard alkylating agent. It has an increased therapeutic index when given as a fractionated dosage over 3-5 days. Maximal fractionation is achieved by continuous infusion over several days and has been shown to be less emetic and neurotoxic than regimens with bolus infusions. We have studied in patients with advanced cancer the feasibility and bioavailability of a subcutaneously administered isotonic and neutral (pH 7) IFO solution given continuously over 10 h for up to 5 days. A portable disposable gas-driven infusor syringe was used. Our results show 90-100% bioavailability of sc administered IFO. The isotonic solution of IFO (pH 7) showed no significant local toxicity during or after sc administration. Haematotoxicity was equal for sc and iv application. No uro- or neurotoxicity has been observed in 24 sc cycles. We conclude that this novel continuous sc IFO infusion over several days is a rational, well-tolerated and economical way of delivering this drug on an outpatient basis.