Abstract
The brain's cells are dependent on their own biosynthesis of cholesterol as the blood-brain barrier prevents uptake from the circulation. In normal glial cells, regulation of cholesterol ...synthesis depends on cell density and is turned off when density exceeds a certain level. Gliomas maintain high levels of cholesterol synthesis genes to support abnormal growth. Upregulation of cholesterol synthesis genes is associated with decreased survival in patients with glioblastoma (GBM). Therefore, gliomas are potentially sensitive to cholesterol synthesis inhibition. DSP-0390, an investigational small molecule, inhibits EBP, an enzyme in one of the last, crucial steps of cholesterol biosynthesis. By inhibiting cholesterol synthesis, cytotoxicity can be induced selectively against hyperproliferative GBM cells. DSP-0390 has shown significant antitumor activity in orthotopic xenograft models of human GBM (data on file).DSP-0390 will be evaluated in a phase 1 study in patients with recurrent, high-grade glioma (NCT05023551). Key eligibility criteria: age >18 years; Karnofsky Performance Status score >70%; adequate renal, hepatic, and hematologic function. Patients must not have multifocal disease, leptomeningeal metastasis or extracranial metastasis, abnormal electrocardiograms, or significant cardiovascular disease. In Dose Escalation, 21-30 patients with World Health Organization (WHO) grade III or IV malignant glioma who progressed after >1 prior therapy will be enrolled. Dose level enrollment will be guided by a Bayesian Logistic Regression Model until identification of the maximum tolerated dose or recommended dose for expansion. Dose Expansion for clinical activity will enroll approximately 20-40 patients with WHO grade IV GBM who progressed after primary therapy and have measurable disease. Patients will receive oral DSP-0390 once daily. Study endpoints include safety (treatment-emergent adverse events AEs, serious AEs, and dose-limiting toxicities), efficacy (6-month progression-free survival PFS, objective response, PFS, duration of response, and 12-month overall survival), pharmacokinetics (PK), and pharmacodynamic biomarkers. This study is currently recruiting in the United States and Japan.
Abstract
INTRODUCTION
Immunotherapies targeting PD-1 in recurrent glioblastoma (rGBM) have shown limited activity. We hypothesize combining therapies targeting immunosuppressive pathways with ...cytotoxic and antiangiogenic therapies will improve survival. This nonrandomized, noncomparative Phase II study examines safety and efficacy of an anti-PD-1 monoclonal antibody (retifanlimab), hypofractionated radiotherapy (HFRT), and bevacizumab, with or without an IDO1 inhibitor (epacadostat), in patients with rGBM.
METHODS
This is an open-label Phase II study of two regimens. Regimen A examines retifanlimab (500mg IV Q4W) + bevacizumab (10mg/kg IV Q2W) + HFRT (3.5Gy/day x 10) in patients with IDH1/2-WT rGBM. Regimen B adds epacadostat. Key inclusions include dexamethasone ≤ 4 mg/day and reirradiation candidacy. The primary endpoint is overall survival (OS) probability at 9 months (OS-9). An increase of OS-9 from 38% (bevacizumab alone) to 60% was considered clinically relevant and required 24 efficacy evaluable patients.
RESULTS
Regimen A accrual is complete; interim results are as follows: 26 rGBM enrolled, with 24 evaluable median age 64.2 years (42.1-81.8); 29% female; 29% MGMT promotor methylated; 33.3% with multi-focal disease; median KPS 90 (70-100); median baseline dexamethasone 0 mg (0-4) and ALC 1,000 cells/µl (300-3,700). Patients received a median of 6 cycles as of May 2022 (2-24). Median follow-up is 16.0 months. Interim median PFS is 7.0 months (95%CI: 4.5~11.1) and median OS is 12.2 months (95%CI 7.1~18.0). Regimen A met primary endpoint with OS-9 of 67% (95%CI: 44~82%). Overall response rate is currently 58% (95%CI: 36.94~77.2%). There were five possible immune-related grade 3+ toxicities to date (n = 1 each colitis, vomiting, and seizure; n = 2 diarrhea). Regimen B is enrolling.
CONCLUSIONS
Interim analysis suggests combination retifanlimab, HFRT, and bevacizumab in rGBM is generally well-tolerated, with encouraging OS and PFS at the time of submission. Correlative analysis is ongoing and will be presented at the meeting.
Abstract
BACKGROUND
Standard of care (SOC) and patient survival in glioblastoma have changed little in the past 17 years. We evaluated in a phase 3 trial whether adding an autologous tumor ...lysate-loaded dendritic cell vaccine (murcidencel) to SOC extends survival. Patients and
METHODS
Newly diagnosed glioblastoma patients were randomized 2:1 to either murcidencel or placebo. Under a crossover design, all patients could receive murcidencel following tumor recurrence. All parties remained blinded regarding treatments before recurrence. Patients thus received murcidencel at new diagnosis (nGBM) or at recurrence (rGBM) following crossover from placebo. The primary and secondary endpoints compare overall survival (OS) with contemporaneous, matched external controls. Four sets of analyses were conducted to ensure rigorous matching of the controls, reduce biases, and confirm the robustness of the results.
RESULTS
331 patients were enrolled. With the crossover, 89% received murcidencel. Median OS (mOS) for nGBM patients (n = 232) was 19.3 months from randomization (22.4 months from surgery) with murcidencel vs. 16.5 months from randomization in the controls (HR = 0.80, p = 0.002). Survival at 48 months from randomization was 15.7% vs. 9.9%, and at 60 months was 13% vs. 5.7%. For rGBM (n = 64), mOS was 13.2 months from relapse vs. 7.8 months in the controls (HR = 0.58, p < 0.001). Survival at 24 months post-recurrence was 20.7% vs. 9.6%, and at 30 months post-recurrence was 11.1% vs 5.1%. In nGBM patients with methylated MGMT (n = 90), mOS was 30.2 months from randomization (33 months from surgery) with murcidencel vs. 21.3 months from randomization in the controls (HR = 0.74, p = 0.027). The treatment was well tolerated, with only 5 serious adverse events deemed at least possibly related to the vaccine.
CONCLUSION
Clinically meaningful and statistically significant survival extension was seen in both nGBM and rGBM patients treated with murcidencel and SOC compared with contemporaneous, matched external controls who received SOC alone.
Abstract
Background
The brain's cells are fully dependent on their own de novo biosynthesis of cholesterol as the blood-brain barrier prevents its uptake from the circulation. In normal glial cells, ...proper regulation of cholesterol synthesis depends on its cell density and is turned off when the cell density exceeds a certain level. On the other hand, gliomas maintain high levels of cholesterol synthesis to support abnormal growth under any condition. Upregulation of cholesterol synthesis genes is associated with decreased survival in patients with glioblastoma (GBM). Therefore, gliomas are potentially sensitive to cholesterol synthesis inhibition. DSP-0390 is an investigational small molecule inhibitor of EBP, an enzyme in one of the last steps of cholesterol biosynthesis. By inhibiting de novo cholesterol synthesis, cytotoxicity can be induced more selectively against hyperproliferative GBM cells. DSP-0390 has shown significant antitumor activity in orthotopic xenograft GBM models (data on file).
Methods
DSP-0390 will be evaluated in a phase 1 study in patients with recurrent high-grade glioma (NCT05023551). Key eligibility criteria: age ≥18 years; KPS score ≥70%; and adequate organ and hematologic function. Patients must not have multifocal disease, leptomeningeal metastasis, extracranial metastasis. In Dose Escalation, 21-30 patients with World Health Organization (WHO) grade III or IV malignant glioma who progressed after ≥1 prior therapy will be enrolled. Dose escalation will be guided by a Bayesian Logistic Regression Model until identification of the maximum tolerated dose or recommended dose for expansion. Dose Expansion will enroll approximately 20-40 patients with WHO grade IV GBM who progressed after primary therapy and have measurable disease. Study endpoints include safety (treatment-emergent adverse events AEs, serious AEs, and dose-limiting toxicities), efficacy (6-month progression-free survival PFS, objective response, PFS, duration of response, and 12-month overall survival), pharmacokinetics (PK), and pharmacodynamic biomarkers. This study is currently recruiting in the United States and Japan.
