GEINOFOTE: efficacy and safety of fotemustine in patients with high-grade recurrent gliomas and poor performance status

Recurrent Glioblastoma: Ongoing Clinical Challenges and Future Prospects

Virtually all glioblastomas treated in the first-line setting will recur in a short period of time, and the search for alternative effective treatments has so far been unsuccessful. Various obstacles remain unresolved, and no effective salvage therapy for recurrent glioblastoma can be envisaged in the short term. One of the main impediments to progress is the low incidence of the disease itself in comparison with other pathologies, which will be made even lower by the recent WHO classification of gliomas, which includes molecular alterations. This new classification helps refine patient prognosis but does not clarify the most appropriate treatment. Other impediments are related to clinical trials: glioblastoma patients are often excluded from trials due to their advanced age and limiting neurological symptoms; there is also the question of how best to measure treatment efficacy, which conditions the design of trials and can affect the acceptance of results by oncologists and medicine agencies. Other obstacles are related to the drugs themselves: most treatments cannot cross the blood-brain-barrier or the brain-to-tumor barrier to reach therapeutic drug levels in the tumor without producing toxicity; the drugs under study may have adverse metabolic interactions with those required for symptom control; identifying the target of the drug can be a complex issue. Additionally, the optimal method of treatment - local vs systemic therapy, the choice of chemotherapy, irradiation, targeted therapy, immunotherapy, or a combination thereof - is not yet clear in glioblastoma in comparison with other cancers. Finally, in addition to curing or stabilizing the disease, glioblastoma therapy should aim at maintaining the neurological status of the patients to enable them to return to their previous lifestyle. Here we review currently available treatments, obstacles in the search for new treatments, and novel lines of research that show promise for the future.

Recurrent Glioblastoma Treatment: State of the Art and Future Perspectives in the Precision Medicine Era

Current treatment guidelines for the management of recurrent glioblastoma (rGBM) are far from definitive, and the prognosis remains dismal. Despite recent advancements in the pharmacological and surgical fields, numerous doubts persist concerning the optimal strategy that clinicians should adopt for patients who fail the first lines of treatment and present signs of progressive disease. With most recurrences being located within the margins of the previously resected lesion, a comprehensive molecular and genetic profiling of rGBM revealed substantial differences compared with newly diagnosed disease. In the present comprehensive review, we sought to examine the current treatment guidelines and the new perspectives that polarize the field of neuro-oncology, strictly focusing on progressive disease. For this purpose, updated PRISMA guidelines were followed to search for pivotal studies and clinical trials published in the last five years. A total of 125 articles discussing locoregional management, radiotherapy, chemotherapy, and immunotherapy strategies were included in our analysis, and salient findings were critically summarized. In addition, an in-depth description of the molecular profile of rGBM and its distinctive characteristics is provided. Finally, we integrate the above-mentioned evidence with the current guidelines published by international societies, including AANS/CNS, EANO, AIOM, and NCCN.

Congress of Neurological Surgeons systematic review and evidence-based guidelines update on the role of cytotoxic chemotherapy and other cytotoxic therapies in the management of progressive glioblastoma in adults

TARGET POPULATION

These recommendations apply to adult patients diagnosed with progressive glioblastoma (pGBM). QUESTION (Q1): In adult patients with pGBM does the use of temozolomide (TMZ) with alternative dosing or the use of TMZ in combination with other cytotoxic treatments result in increased overall survival compared to other chemotherapy?

RECOMMENDATION

Level III: Adult patients with pGBM might derive benefit in treatment with TMZ, especially those who progress after more than 5 months of TMZ-treatment free interval.

LEVEL III

Combination of TMZ with other cytotoxic agents such as nitrosourea, cisplatin, electrohyperthermia, or tamoxifen is not suggested in adult patients with pGBM as a stand-alone therapy. There is insufficient data to make a recommendation about which alternative TMZ dosing provides the best benefits. QUESTION (Q2): In adult patients with pGBM does the use of systemic or in situ nitrosourea result in increased overall survival compared to other chemotherapy?

RECOMMENDATION

Level III: In the setting of pGBM, fotemustine is suggested in elderly patients with methylated MGMT promoter status. There is insufficient evidence to compare fotemustine to other nitrosoureas. There is insufficient evidence to make a recommendation about the use of in situ nitrosourea in patients with pGBM who underwent the Stupp regimen. QUESTION (Q3): In adult patients with pGBM does the use of platinum compounds and topoisomerase result in increased survival compared to other chemotherapy?

RECOMMENDATION

Level III: Other chemotherapy including platinum compounds and topoisomerase inhibitors are not suggested to be used in adult patients with pGBM.

LEVEL III

Other cytotoxic therapies like perillyl acohol or ketogenic diet are not suggested for use in adult patients with pGBM as a stand-alone therapy. QUESTION (Q4): In adult patients with pGBM does the use of tumor treating field (TTF) result in increased overall survival compared to chemotherapy?

RECOMMENDATION

Level III: The use of TTF with other chemotherapy may be considered when treating adult patients with pGBM. There is insufficient evidence to recommend TTF to increase overall survival in adult patients with pGBM. QUESTION (Q5): In adult patients with pGBM does the use of oncolytic virotherapy result in increased survival compared to chemotherapy?

RECOMMENDATION

Level III: Oncolytic virotherapy is not suggested in patients with pGBM.

Biweekly fotemustine schedule for recurrent glioblastoma in the elderly: activity and toxicity assessment of a multicenter study

Aim: To assess the efficacy and safety of alternative fotemustine administration schedule in elderly patients with recurrent glioblastoma. Patients & methods: Patients aged >65 years with recurrent glioblastoma received fotemustine (80 mg/m2; days 1, 15, 30, 45 and 60, and subsequently every 4 weeks). Primary end point was progression-free survival (PFS) rate at 6 months. Main secondary end point was safety. Results: 58 patients were enrolled at two centers. PFS at 6 months was 47% (27 patients) and overall response rate was 29%. Median PFS and survival were 6 and 7 months, respectively, and longer in responders versus nonresponders. No grade 3-4 hematological toxicities occurred. Conclusion: The alternative fotemustine administration schedule was an effective and safe treatment for recurrent glioblastoma in elderly patients.

High-dose fotemustine in temozolomide-pretreated glioblastoma multiforme patients: A phase I/II trial

BACKGROUND

Glioblastoma multiforme (GBM) is a rare and deadly disease, with a reported average incidence rate of 3.19 cases per 100,000 inhabitants. Fotemustine, a third-generation nitrosourea with an alanine phosphor carrier that facilitates cellular penetration, has been extensively investigated in the setting of recurrent/progressive disease after initial treatment. Fotemustine is usually administered following a schedule consisting of 3 doses every week, followed by maintenance doses administered every 3 weeks.

METHODS

In this phase I/II trial, we aimed to assess whether the use of a biweekly regimen allowed administration of higher dose than the standard 100 mg/m dose approved per label indication in a population of patients with recurrent GBM. In this phase I/II trial, fotemustine was administered intravenously over 1 hour every 2 weeks at either 120 or 140 mg/m doses for up to 1 year, until disease progression, unacceptable toxicity, or patient's request to withdraw from the study. The phase I part of the trial was conducted following the classic 3+3 study design. The phase II part of the trial was a single-arm study. The primary efficacy endpoint was the percentage of patients who had not progressed after 24 weeks (PFS-24).

RESULTS

Thirty-seven patients were enrolled in this phase I/II trial from August 2006 to November 2011. Treatment was well tolerated in the overall population. Main severe toxicity was grades 3 and 4 thrombocytopenia, which occurred in 4 of 6 patients treated at the 140 mg/m dose level and in 3 of 31 patients treated at 120 mg/m. Median PFS and overall survival were 12.1 (1-40.2) weeks and 19.7 (1-102) weeks, respectively.

CONCLUSION

We conclude that fotemustine can be safely administered at 120 mg/m biweekly. The efficacy of such modified schedule and doses should be compared to the biweekly schedule at 80 mg and the standard weekly schedule at 80 to 100 mg/m.