TiO2 photocatalytic degradation and transformation of oxazaphosphorine drugs in an aqueous environment

This study investigated the TiO2 photocatalytic degradation and transformation of the oxazaphosphorines ifosfamide (IFO), cyclophosphamide (CP) and trofosfamide (TRO). Under the optimum conditions of TiO2=100mg/L, IFO=100μg/L and solution pH=5.5, IFO was completely removed within 10min (k=0.433min(-1)). The results indicated that OHfree radicals generated by valence holes in the bulk solution were the predominant species for the degradation of IFO. At higher initial concentrations of oxazaphosphorines (20mg/L), >50% of TOC remained after 6h of reaction time, indicating that parent compounds were transformed to byproducts, which exhibit higher Microtox acute toxicities; chlorinated byproducts were likely the source of toxicity. Photocatalytic degradation pathways of the three oxazaphosphorines were proposed. IFO, CP and TRO follow very similar pathways and bond-breaking processes: ketonization and breaking of the CCl bond, the PN bond and the CN bond (N-dechloroethylation). Chloride (Cl(-)) release is likely the first and primary step in the decomposition process. Several of the identified byproducts were also metabolites, which implies that photocatalytic oxidation proceeds through pathways that are similar to metabolic pathways.

Old wine in new pipes? Treatment of advanced non-small cell lung cancer with trofosfamide

BACKGROUND

The aim of this retrospective study was to examine the effect of oral trofosfamide in patients with advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients with histologically or cytologically proven NSCLC, who had received at least 2 other therapies, were enrolled. The primary clinical end point was progression-free survival (PFS); secondary end points included overall survival (OS), response rate and toxicity.

RESULTS

23 patients were enrolled, 1 of whom was excluded due to non-compliance. The patients had received a median of 3 prior therapies (range 2-4). Regarding all 22 patients, median PFS was 14 weeks (95% confidence interval (CI) 9.96-18.04). The median OS was 32 weeks (95% CI 17.12-46.88). The median duration of trofosfamide therapy was 10.5 weeks (interquartile range 6.5-17.3). 20 patients (90.9%) had stable disease; 2 were not assessable. Trofosfamide therapy was stopped in 4 patients (18.2%) due to side effects.

CONCLUSION

Trofosfamide is an orally applicable, well-tolerated and cost-effective drug that works in patients with advanced NSCLC, who have undergone at least 2 lines of therapy. Trofosfamide seems to be a therapeutic option in NSCLC as a further therapy line. These preliminary data need to be confirmed in a larger trial.

Dose escalation study for defining the maximum tolerated dose of continuous oral trofosfamide in pretreated patients with metastatic lung cancer

BACKGROUND

Trofosfamide is increasingly used in the treatment of patients with several types of malignancies. However, the optimal dose of trofosfamide for patients with advanced cancer has not been systematically investigated yet. The aim of this study was to define the maximum tolerated dose (MTD) of continuous oral trofosfamide.

PATIENTS AND METHODS

16 patients with advanced lung cancer (14 nonsmall cell lung cancer, 2 small cell lung cancer; 10 male, 6 female; median age 64 years (range 46-82); median Karnofsky status 70%; median number of organs involved 3 (range 1-6)) were enrolled. All patients were previously treated with chemotherapy (median 2x, range 1-6) and 8/16 (50%) with radiotherapy. Patients received trofosfamide p.o. administered in 3 doses per day for 3 weeks (1 cycle) using a 3-patient-cohort dose-escalation strategy. Toxicities were graded according to the WHO Criteria.

RESULTS

Patients received a median of 2 cycles of trofosfamide (range 1-4) at 3 dose levels (90, 125, and 175 mg/m2). Grade 3 and 4 neutropenia, anemia, and thrombocytopenia were observed in 20, 13.3, and 6.6%, respectively. Dose-limiting toxicities during the first cycle were grade 3 muscle weakness and anorexia observed in 1/6 patients in cohort 1 (trofosfamide 90 mg/m2), grade 3 neutropenia in 1/6, and encephalopathy in 1/6 patients in cohort 3 (trofosfamide 175 mg/m2). Therefore, the dose level of 125 mg/m2 was defined as the MTD.

CONCLUSION

Trofosfamide at 125 mg/m2 administered in 3 doses per day was well tolerated. This dose level is recommended for further clinical studies.

Trofosfamide in the Palliative Treatment of Cancer: A Review of the Literature

Trofosfamide is an alkylating agent that is derived from the oxazaphoshorines. It has found application in a broad spectrum of malignancies in the last three decades. The main indications for application were in the palliative situation and as maintenance therapy. Good results were reported from the treatment of non-Hodgkin's lymphomas and soft tissue sarcomas. A lot of small studies and casuistic contributions are available giving treatment results of several solid carcinomas (malignant gliomas, ovarian, lung and prostate cancer, and others). Due to its oral formulation and good tolerability trofosfamide is an attractive candidate for the palliative situation because treatment on an outpatient basis is possible. However, there is still a lack of randomized clinical studies with trofosfamide. Thus, evidence-based conclusions on the therapeutic value of the drug cannot be drawn. In the future, phase III trials should be undertaken.