SurVaxM Improves OS Only in Younger Subgroup in Newly Diagnosed Glioblastoma

Adding the survivin-targeted vaccine SurVaxM to standard therapy did not reach a statistically significant overall survival (OS) improvement over placebo in the overall population of a randomized trial in newly diagnosed glioblastoma. However, a significant OS benefit was seen in a prespecified subgroup of patients aged 65 years or younger.¹

In the phase 2b SURVIVE trial (NCT05163080), median OS among all 233 evaluable patients was 22.8 months with SurVaxM vs 20.3 months with placebo, but this 2.5-month difference did not meet statistical significance (HR, 0.75; 95% CI, 0.54-1.03; P = .076). Among patients aged 65 years or younger, median OS was 24.2 months vs 20.2 months, respectively (HR, 0.64; 95% CI, 0.44-0.93; P = .019). Both P-values were adjusted for MGMT and Karnofsky performance status (KPS) stratification. MimiVax, the sponsor, characterized the result in the full population as clinically meaningful in a news release.

"In a disease where we've had limited progress over the last 20 years, an improvement in survival of this magnitude is noteworthy," Ajay Abad, MD, principal investigator of the study and assistant professor of oncology and neurology in the Department of Neuro-Oncology at Roswell Park Comprehensive Cancer Center in Buffalo, New York, stated in the news release.

Background and Trial Design

SurVaxM is a peptide-mimic vaccine given by subcutaneous injection that is intended to direct the immune system against cells expressing survivin, a cell-survival protein present in approximately 95% of glioblastomas. The vaccine is investigational and holds FDA orphan drug and fast track designations for newly diagnosed glioblastoma.

SURVIVE is a double-blind, placebo-controlled study that opened in 2022 and was conducted at 11 US cancer centers. Adults with a KPS of 70 or higher who had undergone resection were randomly assigned 3:2 to SurVaxM or saline placebo, each given with adjuvant temozolomide. The primary end point was OS, and secondary end points included progression-free survival (PFS), landmark survival, safety, and survivin-specific immune responses.

Subgroup and Long-Term Survival Findings

Approximately 42% of patients aged 65 years or younger who received SurVaxM were alive at 30 months or later vs 18% of those who received placebo, and no additional deaths were recorded in the vaccine group between 30 and 54 months.

PFS also favored SurVaxM in the younger subgroup (HR, 0.64; P = .018). At 12 months, 44% of these patients in the vaccine arm were progression free compared with 24% in the placebo arm.

Patients assigned to placebo lived longer than the trial's design anticipated. Median OS in the control arm was 20.3 months, whereas the design assumed a historical benchmark of 16 months. This unexpected duration of OS made a significant difference in the full population harder to demonstrate.

"We designed the trial to provide a good comparison to our earlier phase 2a study, while adding a placebo arm to account for improvements in standard of care that may have occurred over time," explained Robert Fenstermaker, MD, co-principal investigator of SURVIVE, chair emeritus of neurosurgery at Roswell Park, and chief medical officer and cofounder of MimiVax, in the news release.

The sponsor stated that the outcomes were in line with the immunotherapeutic mechanism and earlier phase 2a results that led to the randomized trial.^1,2

Safety Findings

Grade 3 or higher adverse events (AEs) occurred in 48% of patients in the SurVaxM arm and 46% in the placebo arm, and serious AEs occurred in 25% and 21%, respectively. No treatment-related deaths were reported in either arm. AEs led 4% of patients in the SurVaxM arm to stop treatment, including 1 discontinuation attributed to study treatment.

The most common adverse events with the vaccine were grade 1 or 2 injection-site effects: injection-site reaction (48%), pain (41%), erythema (39%), pruritus (38%), and swelling (29%). Influenza-like illness was reported in 13%.

Mechanism and Regulatory Status

MimiVax stated that it will request a meeting with the FDA in the next months so that the agency can review the SURVIVE results and discuss breakthrough therapy designation and other expedited pathways, including accelerated approval of SurVaxM.

REFERENCES

1. MimiVax and Roswell Park Announce Results from Phase 2b SURVIVE Trial of SurVaxM in Newly Diagnosed Glioblastoma. News release. MimiVax, Inc. October 7, 2026. Accessed October 7, 2026. https://tinyurl.com/fdxy972k

2 Ahluwalia MS, Ciesielski M, Abad A, et al. A randomized phase 2b study of survivin vaccine SurVaxM plus adjuvant temozolomide for newly-diagnosed glioblastoma (SURVIVE). Neuro Oncol. 2023;25(suppl 2):ii52-ii53. doi:10.1093/neuonc/noad137.169