Stacy Matthews Branch, DVM, PhD
Brain Cancer Vaccine for Gliomas Moves Forward in the Clinic
The vaccine was designed to assist a patient’s immune system target brain tumors more effectively and efficiently
Gliomas are brain cancers that are considered rare disorders that affect 6.6 out of 100,000 individuals yearly worldwide.
Conventional treatment approaches include surgery, radiotherapy, and chemotherapy, but gliomas remain challenging to treat effectively. A subtype of diffuse gliomas has a unique and common mutation in the isocitrate dehydrogenase 1 (IDH1) gene and is responsible for the production of neo-epitopes. In the search for an immunotherapy that can help the immune system combat gliomas, researchers from the University Hospital Heidelberg, German Cancer Research Center, conducted a Phase 1 clinical trial with an IDH1 mutation–specific peptide vaccine (IDH1-vac).
The IDH1-vac was previously found to induce specific helper T cells and to be effective against IDH1 mutant glioma tumors in MHC-humanized mice. The Phase 1 trial was conducted in 33 patients who were newly diagnosed with grade 3 or 4 IDH1-mutant glioma tumors with the goal to determine the safety of IDH1-vac in humans and the nature of the immune response elicited. Results of the Phase 1 trial showed that treatment with IDH1-vac had a favorable safety profile limited to grade I adverse events, and immune responses were detected in 93% of the study patients.
Flow cytometric effector phenotyping of peripheral IDH1-vac-induced T cells from patient samples showed that helper T cells produced various cytokines, including tumor necrosis factor, interferon-gamma, and interleukin-17 when re-stimulated with IDH1-mutant antigen in vitro. In addition to the safety data obtained in the study, the patient survival rate was found to be 84% at the 3-year follow-up point. Strong immune responses were observed in 82% of the patients, and no tumor growth was detected in these patients by 3 years post-treatment.
Although these results are quite promising, there was no control group in the study, and a larger clinical trial is warranted. There is a Phase 2 trial in the planning, and another active Phase 1 trial combines the vaccine treatment and the use of a checkpoint inhibitor to bolster the immune response. Targeting a common mutation in diffuse gliomas may help to overcome the resistance that can be seen with checkpoint inhibitor–only therapy and increase glioma treatment success.
Landmark brain cancer vaccine passes first phase of human trials. (2021). Retrieved 11 May 2021, from https://newatlas.com/medical/brain-cancer-vaccine-idh1-glioma-human-trials/
This article was written by free-lance science writer Stacy Matthews Branch, DVM, PhD. It originally appeared on a blog managed by HemaCare, which Charles River acquired in 2020. HemaCare sells biological products such as T cells, stem cells, bone marrow, plasma, and other medical products. When conducting medical research, you want to have the best products available to you. If you are looking to purchase cellular products, contact HemaCare with any questions you may have.