Prolonged infusional topotecan and accelerated hyperfractionated 3d-conformal radiation in patients with newly diagnosed glioblastoma--a phase I study

Non-PEGylated liposomes for convection-enhanced delivery of topotecan and gadodiamide in malignant glioma: initial experience

Convection-enhanced delivery (CED) of highly stable PEGylated liposomes encapsulating chemotherapeutic drugs has previously been effective against malignant glioma xenografts. We have developed a novel, convectable non-PEGylated liposomal formulation that can be used to encapsulate both the topoisomerase I inhibitor topotecan (topoCED™) and paramagnetic gadodiamide (gadoCED™), providing an ideal basis for real-time monitoring of drug distribution. Tissue retention of topoCED following single CED administration was significantly improved relative to free topotecan. At a dose of 10 μg (0.5 mg/ml), topoCED had a half-life in brain of approximately 1 day and increased the area under the concentration–time curve (AUC) by 28-fold over free topotecan (153.8 vs. 5.5 μg day/g). The combination of topoCED and gadoCED was found to co-convect well in both naïve rat brain and malignant glioma xenografts (correlation coefficients 0.97–0.99). In a U87MG cell assay, the 50% inhibitory concentration (IC₅₀) of topoCED was approximately 0.8 μM at 48 and 72 h; its concentration–time curves were similar to free topotecan and unaffected by gadoCED. In a U87MG intracranial rat xenograft model, a two-dose CED regimen of topoCED co-infused with gadoCED greatly increased median overall survival at dose levels of 0.5 mg/ml (29.5 days) and 1.0 mg/ml (33.0 days) vs. control (20.0 days; P < 0.0001 for both comparisons). TopoCED at higher concentrations (1.6 mg/ml) co-infused with gadoCED showed no evidence of histopathological changes attributable to either agent. The positive results of tissue pharmacokinetics, co-convection, cytotoxicity, efficacy, and lack of toxicity of topoCED in a clinically meaningful dose range, combined with an ideal matched-liposome paramagnetic agent, gadoCED, implicates further clinical applications of this therapy in the treatment of malignant glioma.

Topotecan in combination with radiotherapy in unresectable glioblastoma: a phase 2 study

Improving glioblastoma multiforme (GBM) treatment with radio-chemotherapy remains a challenge. Topotecan is an attractive option as it exhibits growth inhibition of human glioma as well as brain penetration. The present study assessed the combination of radiotherapy (60 Gy/30 fractions/40 days) and topotecan (0.9 mg/m(2)/day on days 1-5 on weeks 1, 3 and 5) in 50 adults with histologically proven and untreated GBM. The incidence of non-hematological toxicities was low and grade 3-4 hematological toxicities were reported in 20 patients (mainly lymphopenia and neutropenia). Partial response and stabilization rates were 2% and 32%, respectively, with an overall time to progression of 12 weeks. One-year overall survival (OS) rate was 42%, with a median OS of 40 weeks. Topotecan in combination with radiotherapy was well tolerated. However, while response and stabilization concerned one-third of the patients, the study did not show increased benefits in terms of survival in patients with unresectable GBM.

Topotecan as a radiosensitizer in the treatment of children with malignant diffuse brainstem gliomas: results of a French Society of Paediatric Oncology Phase II Study

BACKGROUND

The current Phase II study was conducted to evaluate the survival and toxicity observed in children with newly diagnosed brainstem gliomas who were treated with the daily radiotherapy with topotecan used as a radiosensitizer.

METHODS

Eligible patients were those ages 3-18 years with previously untreated tumors arising in the pons diagnosed within the previous 6 months. Histologic confirmation was not mandatory provided that the clinical and magnetic resonance imaging findings were typical for a diffusely infiltrating brainstem lesion. Treatment was comprised of a 6-week course of topotecan administered intravenously at a dose of 0.4 mg/m(2)/day over 30 minutes within 1 hour before irradiation. Radiotherapy was comprised of a once-daily treatment of 1.8 grays (Gy) per fraction to a total dose of 54 Gy.

RESULTS

Thirty-two patients were included in the current study between August 2000 and October 2002. All patients completed the combined treatment in accordance with the treatment design. Only partial responses were observed, occurring in 40% of the patients. The 9-month and 12-month survival rates were 34.4% +/- 8% and 25.5% +/- 8%, respectively. The median duration of survival for these 32 patients was 8.3 months. An intratumoral cystic/necrotic change was observed in five patients, with clinical impairment noted in two patients. One intratumoral hemorrhage occurred during radiotherapy, and was associated with transitory neurologic impairment.

CONCLUSIONS

The findings of the current study regarding newly diagnosed brainstem glioma patients treated with topotecan given as a radiosensitizing agent did not reproduce the encouraging results obtained in preclinical studies. Therefore, the concomitant combination of topotecan and radiotherapy at this schedule and these doses cannot be recommended for the treatment of patients with brainstem gliomas.

Concurrent chemoradiotherapy and adjuvant chemotherapy with Topotecan for patients with glioblastoma multiforme

PURPOSE

The prognosis for patients with glioblastoma multiforme remains poor. Phase II studies, meta-analyses and a phase III study show that concurrent chemoradiotherapy has an advantage over irradiation alone. In this study the effectiveness of concurrent chemoradiotherapy with Topotecan and an adjuvant chemotherapy with Topotecan was investigated.

PATIENTS AND METHOD

Forty-two patients with predominantly unfavourable prognosis factors were included in the study and treated as follows: hyperfractionated accelerated radiotherapy (2x1.75Gy to 45.5 + 12.25 Gy (RP)) with a concurrent, continuous infusion of Topotecan (0.5 mg/m(2)/d, days 1-21). On day 28 the adjuvant chemotherapy (three courses) was begun according to the same scheme.

RESULT

Haematological toxicities were 13/42 (30%) grade III leucopenia, 2/42 (4%) grade IV, as well as 5/42 (10%) grade III thrombopenias and 1/42 (2%) grade IV. 30/42 (71%) patients showed improvement or stabilisation of an existing neurological symptomatic complex. The median time to progression was 7.2 (+/- 0.8) months, the median total survival was 10 (+/- 1.2) months, the 2 year survival rate 4.7 (+/- 0.3)%. Prognostic factors were age, surgical radicality, performance status and the tumour volume before therapy.

SUMMARY

Concurrent chemoradiotherapy and an adjuvant chemotherapy with Topotecan is feasible at acceptable toxicity levels also for patients with a moderate performance status. The patients benefit from the improvement of the clinical symptomatic complex and, even with unfavourable prognosis factors, have a higher median survival in comparison to data published on similar groups of patients given only radiotherapy.

Prolonged Oral Hydroxyurea and Concurrent 3d-Conformal Radiation in Patients with Progressive or Recurrent Meningioma: Results of a Pilot Study

PURPOSE

Treatment of recurrent and progressive meningiomas remains a challenge in clinical neurooncology. This study was designed to evaluate the efficacy of the simultaneous application of 3d-conformal radiotherapy and chemotherapy with hydroxyurea (HU).

PATIENTS AND METHODS

Twenty-one patients with recurrent or progressive meningiomas (13 benign, 4 atypical and malignant, 4 with unproven histology) received treatment by fractionated 3d-conformal radiation (55.8-59.4 Gy) and concurrent HU, administered for a median time of three months with a daily dosage of 20 mg/kg. Response was evaluated using clinical and neuro-imaging data.

RESULTS

Disease stabilization was achieved in 14/21 patients (pts). Three pts had significant improvement of tumor associated neurological symptoms with imaging criteria of minor response. Progression free survival rates 1 year and 2 years after the initiation of radio-chemotherapy were 84% and 77%, respectively. At the time of analysis a total of 6/21 pts presented with progressive disease with a median time to progression of 59 weeks. Documented radio- and chemotherapy associated toxicity was minimal; only one patient discontinued HU treatment due to gastrointestinal symptoms such as anorexia and weight loss.

CONCLUSION

Results obtained in this study indicate that treatment with HU and simultaneous radiotherapy is safe and effective with disease stabilization in the majority of patients. Randomized trials comparing radiosurgery versus radiochemotherapy versus fractionated radiotherapy are warranted.