The investigational cancer immunotherapy SurVaxM given in combination with standard therapy improved survival time among people with glioblastoma, the most aggressive and common form of brain cancer.
Researchers presented findings from the five-center, single-arm Phase II clinical trial of 63 people with newly diagnosed glioblastoma at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago last week.
SurVaxM has been developed by Robert Fenstermaker, MD, chair of neurosurgery at Roswell Park Comprehensive Cancer Center and Michael Ciesielski, PhD, assistant professor of neurosurgery at the same center. The novel vaccine, which provides a unique approach to cancer immunotherapy, stimulates a multipronged response from the immune system that targets an antigen called survivin that is key to tumor survival. Nonmalignant cells generally do not express this antigen.
The study participants had a median age of 60 years old, and 60% were male. All of them received standard glioblastoma treatment, including craniotomy (removal of part of the skull), radiation and treatment with temozolomide both prior to and following their surgery. They received four biweekly subcutaneous injections of 500 micrograms of SurVaxM along with the adjuvants Montanide and Leukine (sagramostim). Then they received SurVaxM with the adjuvants every 12 weeks until their cancer progressed.
The participants were followed for safety, six-month progression-free survival, 12-month overall survival and immunologic response. The investigators assessed the participants’ immune response by detecting an antibody specific to survivin as well as CD8 T-cell levels.
Compared to historical data from others who received standard glioblastoma treatment without SurVaxM, combination treatment with the vaccine plus standard treatment yielded promising results, both in terms of efficacy and the treatment’s capacity to stimulate an immune response.
Within six months of treatment, 96.8% of participants were still living and did not see their disease progress, known as progression-free survival (PFS); at 12 months, the PFS rate was 58.4%. Additionally, 93.5% were still living a year following their diagnosis, compared with an expected overall survival rate of around 65% based on historical comparisons. Among participants who were still being followed two years after their diagnosis, the overall survival rate was 58.4%. The median post-diagnosis overall survival time was 30.5 months for those receiving SurVaxM; meanwhile, the expected survival time for those receiving standard treatment is around 15 months.
SurVaxM was also linked to an increase in survivin-specific immune responses.
Treatment had minimal toxicity and side effects. The most common adverse event was injection-site reactions, usually mild or moderate (grade 1 or 2).
“We essentially saw significant increase in both progression-free and overall survival, which is noteworthy in patients with such a notoriously aggressive and treatment-resistant disease,” Fenstermaker, who was the senior author on the study, said in a Roswell Park press release.
“We were especially pleased to see that even patients with poor prognostic factors like high levels of surviving responded well to this combination of standard therapy plus SurVaxM,” added Ciesielski, who presented the study’s findings in a poster presentation at the ASCO meeting.The researchers are gearing up to run randomized clinical trials of SurVaxM. The Food and Drug Administration granted SurVaxM an orphan drug designation in 2017.
To read the conference abstract, click here.
To read about the SurVaxM’s orphan status approval from the Food and Drug Administration, click here.