Olutasidenib (FT-2102) in patients with relapsed or refractory IDH1-mutant glioma: A multicenter, open-label, phase Ib/II trial

BACKGROUND: Olutasidenib (FT-2102) is a highly potent, orally bioavailable, brain-penetrant and selective inhibitor of mutant isocitrate dehydrogenase 1 (IDH1). The aim of the study was to determine the safety and clinical activity of olutasidenib in patients with relapsed/refractory gliomas harboring an IDH1R132X mutation. METHODS: This was an open-label, multicenter, nonrandomized, phase Ib/II clinical trial. Eligible patients (≥18 years) had histologically confirmed IDH1R132X-mutated glioma that relapsed or progressed on or following standard therapy and had measurable disease. Patients received olutasidenib, 150 mg orally twice daily (BID) in continuous 28-day cycles. The primary endpoints were dose-limiting toxicities (DLTs) (cycle 1) and safety in phase I and objective response rate using the Modified Response Assessment in Neuro-Oncology criteria in phase II. RESULTS: Twenty-six patients were enrolled and followed for a median 15.1 months (7.3‒19.4). No DLTs were observed in the single-agent glioma cohort and the pharmacokinetic relationship supported olutasidenib 150 mg BID as the recommended phase II dose. In the response-evaluable population, disease control rate (objective response plus stable disease) was 48%. Two (8%) patients demonstrated a best response of partial response and eight (32%) had stable disease for at least 4 months. Grade 3‒4 adverse events (≥10%) included alanine aminotransferase increased and aspartate aminotransferase increased (three [12%], each). CONCLUSIONS: Olutasidenib 150 mg BID was well tolerated in patients with relapsed/refractory gliomas harboring an IDH1R132X mutation and demonstrated preliminary evidence of clinical activity in this heavily pretreated population

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Adult-type Diffuse Gliomas

This article highlights key aspects of the diagnosis and management of adult-type diffuse gliomas, including glioblastomas and IDH-mutant gliomas relevant to the daily practice of the general neurologist. The advances in molecular characterization of gliomas have translated into more accurate prognostication and tumor classification. Gliomas previously categorized by histological appearance solely as astrocytomas or oligodendrogliomas are now also defined by molecular features. Furthermore, ongoing clinical trials have incorporated these advances to tailor more effective treatments for specific glioma subtypes. Despite recent insights into the molecular aspects of gliomas, these tumors remain incurable. Care for patients with these complex tumors requires a multidisciplinary team in which the general neurologist has an important role. Efforts focus on translating the latest data into more effective therapies that can prolong survival

Targeting IDH1/IDH2 mutations in gliomas

Purpose of reviewSomatic point mutations in the metabolic enzyme isocitrate dehydrogenase (IDH) are a defining feature of the majority of WHO grade 2-3 diffuse glioma and the most powerful positive prognostic factor for survival in gliomas. The purpose is to review experimental therapeutic approaches targeting IDH mutations in gliomas including small-molecule inhibitors, immunotherapies, and agents targeting mutant IDH-induced epigenetic and metabolic vulnerabilities.Recent findingsExtensive preclinical work supports targeting mutant IDH (mIDH) in glioma. In heavily pretreated patients with mIDH glioma, enzyme inhibitors demonstrated to be well tolerated with preliminary evidence of clinical activity in nonenhancing tumors and enhancing tumors when used as single agents. In patients with newly diagnosed WHO grade 3 or 4 astrocytomas, a phase 1 study of a vaccine-targeting IDH1 R132H showed to be well tolerated and demonstrated immunogenicity with a 3-year progression-free and overall survival rates of 0.63 and 0.84, respectively. A variety of ongoing trials aim to target mIDH, including treatments with single agents or combinatory approaches in the upfront or recurrent setting.mIDH are commonly found in gliomas and play a key role in gliomagenesis. This has led to studies using agents to directly inhibit them, immunotherapies, and epigenetic/metabolic drugs with varying and promising results. Ongoing studies may elucidate the precise role of these therapies and the best timing for treatment within the disease course

Chapter 34 - Chemotherapy for Primary Central Nervous System Lymphoma

In this chapter, commonly used chemotherapy regimens for primary central nervous system (CNS) lymphoma are discussed in the context of an overall approach to the disease. In the newly diagnosed setting, the mainstay of treatment remains methotrexate-based chemotherapy. Several effective multiagent methotrexate-based regimens have reported interesting results, although randomized studies are few. In the United States, the most common regimens are rituximab, procarbazine, vincristine, and cytarabine (R-MPV-A) and rituximab, methotrexate, temozolomide, cytarabine, and etoposide (R-MT-EA). Myeloablative chemotherapy regimens, particularly thiotepa, busulfan, and cyclophosphamide (TBC) followed by stem-cell transplant (ASCT) have emerged as powerful consolidation tools, although the optimal timing remains to be determined. The different available regimens will be discussed, with emphasis on efficacy and relative risks and benefits

The role of ventriculoperitoneal shunting in patients with supratentorial glioma

To assess the impact of ventriculoperitoneal (VPS) in patients with glioma. Retrospective review of patients with grade II-IV glioma who had VPS placement from January 1995 to November 2012. We identified 62 patients. At time of VPS, 41 had gait disturbance, 40 cognitive impairment and 16 urinary incontinence; 10 had the classic triad. Thirty-eight (61%) improved after VPS. Median overall survival from VPS was 7 months for all patients, but 11 months for those who improved and 2 months for non-responders. Leptomeningeal disease, glioma grade or radiographic ventricular decompression did not predict benefit. VPS can improve functional status in some patients with symptoms suggestive of hydrocephalus

INNV-30. RESPONSE WITH COMBINED DABRAFENIB AND TRAMETINIB AFTER BRAF INHIBITOR FAILURE IN BRAF-MUTATED GLIOBLASTOMA: A CASE REPORT

Glioblastoma (GBM) carries a poor prognosis despite aggressive multimodality therapy. Oncogenic BRAF mutations are present in < 2% of GBM, along with other glioma types (ganglioglioma, pleomorphic xanthoastrocytoma). Although oral inhibitors of the oncogenic BRAFv600 kinase have demonstrated some efficacy in GBM, several mechanisms mediating resistance to BRAF inhibitors through MAPK reactivation have been described. BRAF inhibitor monotherapy is also associated with an increased risk for hyperproliferative skin lesions. We present a case of a 44-year-old man who initially presented with headaches and seizures and was diagnosed with a left temporal, MGMT unmethylated, BRAF V600E mutant GBM. He underwent gross total resection followed by radiation therapy with concurrent temozolomide, followed by 9 cycles of adjuvant temozolomide. He presented with progression of disease (POD) and subsequently failed treatment with carboplatin after two cycles (first recurrence). He had a repeat resection, and was enrolled in a clinical trial of autologous dendritic cell vaccine and presented with POD after 10 months on this treatment (second recurrence). He was started on another clinical trial of BRAF inhibitor, achieving partial response but developed POD after 7 months on this therapy (third recurrence). He was started on BRAF inhibitor dabrafenib and MEK inhibitor trametinib (D+T), achieving complete response. At the time of this report, 8 months after initiating treatment, the patient remains clinically stable with MRI showing CR. To our knowledge, this is the first report of clinical and radiographic response to combined D+T after BRAF inhibitor failure in BRAF-mutated glioblastoma. Several ongoing trials (NCT01677741, NCT01748149, NCT02124772, NCT02684058, NCT02285439), will elucidate the precise role of these drugs as single agent and in combination in pediatric and adult brain tumors

The role of bevacizumab in the treatment of glioblastoma

Bevacizumab has been used in patients with GBM as a salvage therapy since its approval in the United States for recurrent GBM in 2009. In order to review the therapeutic effect of bevacizumab in the primary and recurrent clinical setting we have performed a systematic analysis of data from the published literature. Weighted median progression free survival and overall survival were calculated and compared to standard therapy or other experimental therapies. A qualitative analysis of the limited studies on health related quality of life and effects on steroid requirements was also undertaken. We found that the available literature supports the use of bevacizumab for prolonging PFS and OS in the recurrent setting either alone or in combination with a cytotoxic agent (P \u3c 0.05), but does not support its use in the primary setting (P \u3e 0.05). The survival advantage of bevacizumab compared to experimental therapy at recurrence is limited to 4 months. There is no additional benefit reported to date in health-related quality of life with the use of bevacizumab, although it may reduce steroid requirements. On average there is one side-effect event per patient and 74% of these events are grade 3 toxicity or higher. Further studies investigating the role of bevacizumab in combination with cytotoxic agents at recurrence are awaited