BACKGROUND:
- Glioma is the most common malignant brain tumor. Genes coding for isocitrate
dehydrogenases 1and 2 (IDH1 and IDH2), metabolic enzymes, are frequently mutated in
gliomas, particularly lower-grade gliomas (LGGs). IDH1/2 mutation causes a unique
tumor biology, including the accumulation of 2-hydroxyglutarate (2-HG), an
oncometabolite, which in turn causes genomic hypermethylation and tumorigenesis.
- IDH-mutant LGGs undergo a slow but unremitting progression to higher grade
transformation (HT) and eventually become high grade gliomas (HGGs) with a
significant increase in the number of somatic mutations. A subset of patients with
transformed HGGs develop a hypermutator phenotype (HMP), possibly related, but not
limited, to previous treatment with alkylating agents and radiotherapy. The
mechanisms of this clinical phenomenon are not fully understood, and no effective
treatments are available for the HMP HGGs.
- High tumor mutation burden (TMB) is a characteristic finding in many of the
transformed tumors. Furthermore, this increased mutation burden, with commensurate
increase in neoantigen expression, may be correlated with a better response to
immune checkpoint
inhibitor (ICPIs) treatment.
- Nivolumab is a monoclonal antibody that binds to the PD1 receptor and blocks its
interaction with PD L1 and PD L2 and subsequently releasing PD 1 pathway mediated
inhibition of the immune response, including antitumor immune response.
- The US Food and Drug Administration granted approval to nivolumab for the treatment
of unresectable or metastatic melanoma, advanced non-small cell lung cancer, renal
cell carcinoma, Hodgkin s lymphoma, recurrent or metastatic squamous cell carcinoma
of the head and neck, locally advanced or metastatic urothelial carcinoma,
microsatellite instability-high or mismatched repair deficient metastatic colorectal
cancer and hepatocellular carcinoma.
- The first randomized clinical trial in glioblastoma with nivolumab (CheckMate-143)
was completed in early 2017. Unfortunately, the study didn t meet its primary
endpoint of improved overall survival over bevacizumab monotherapy. The objective
response rate (ORR) was lower in nivolumab arm than bevacizumab arm. However, the
response with nivolumab was more durable. The safety profile of nivolumab was very
consistent with what has been observed in other tumor types.
OBJECTIVE:
-To determine the 6-month progression free survival rate in IDH-mutant gliomas patients
with and without HMP in responses to nivolumab treatment.
ELIGIBILITY:
- Patients with diffuse glioma, confirmed by NCI Laboratory of Pathology
- Age greater than or equal to 18 years
- KPS greater than or equal to 60%
- IDH 1 or IDH 2 mutation confirmed by DNA sequencing
- Patients must have TMB status performed at NIH
- Tumor tissue or slides should be available for molecular and immune profiling
DESIGN:
- This study is an open label phase II clinical trial of the immune checkpoint
inhibitor, nivolumab, in patients with HMP and NHMP IDH-mutant gliomas.
- Patients with HMP and NHMP will receive nivolumab at a standard dose of 240 mg
intravenously every 2 weeks for cycles 1-2, then doses of 480 mg every 4 weeks for
cycles 3-16. A maximum of 20 treatments will be given (16 cycles).
- A maximum of 29 patients with IDH-mutant glioma with HMP (Cohort 1) and 30 patients
with NHMP (Cohort 2) will be evaluated.
- A Simon's optimal two-stage design will be used to conduct the HMP arm and the NHMP
arm independently. For the HMP cohort, in stage I, a total number of 10 patients are
accrued. If 9 or more patients progress by 6 months, the cohort will be terminated
early; otherwise, additional 19 patients will be accrued in stage II, resulting in a
total sample size of 29. Among these 29 patients, if 6 or more patients are
progression-free at 6 months, we will claim that the treatment is promising for
patients with HMP IDH-mutant gliomas. For NHMP cohort, in stage I, a total number of
15 patients are accrued. If 3 or more patients are progression-free at 6 months, the
cohort will move to stage II and an additional 15 patients will be accrued in stage
II, resulting in a total sample size of 30. Among these 30 patients, if 10 or more
patients are progression-free at 6 months, we will claim that the treatment is
promising for patients with NHMP IDH-mutant gliomas.