Glioblastoma trial of VXM01 plus Bavencio shows promising safety
Study enrolled 25 people with cancer treated with surgery, chemoradiation

Combining VXM01, an experimental anticancer vaccine, with Bavencio (avelumab), which activates the immune system to attack cancer cells, was well tolerated in a small clinical study of people with recurrent glioblastoma.
Available data also indicate the combination led to reductions in tumor size in a few of the trial’s participants, according to Vaximm AG, the company developing VXM01.
“The completion of this Phase 2a study is a significant milestone for Vaximm AG, as it provides strong evidence that VXM01, in combination with avelumab is generally well tolerated in patients with recurrent glioblastoma. We are encouraged by these early results and the potential to improve outcomes for patients with this aggressive cancer,” Constance Hoefer, PhD, CEO of Vaximm, said in a company press release.
VXM01 is an oral vaccine designed to induce the immune system to attack VEGFR2, a protein involved in the growth of new blood vessels. Cancer cells require lots of blood flow to get nutrients and oxygen, so tumors tend to be dense with this protein. Bavencio, marketed by Merck, blocks signals that cancer cells sometimes use to hide from the immune system. While Bavencio is approved for some types of cancer, it’s not approved in the U.S. for glioblastoma, an aggressive type of brain cancer.
The Phase 2 clinical trial (NCT03750071) enrolled 25 people with glioblastoma that had come back or kept growing after surgery and chemoradiation. Some patients had tumors that could be removed with surgery, while others had tumors that couldn’t be removed. All the participants in the open-label trial were treated with VXM01 and Bavencio. The study’s main goal was to assess the safety profile of this immune-modulating treatment combo.
No serious side effects from treatment
The results indicated the safety profile was generally favorable. No serious side effects related to the treatment were reported. In fact, almost all the serious safety issues reported were judged to result from the underlying cancer, which “[underscores] the well-manageable safety profile of this combination therapy in a frail patient population,” according to Vaximm.
In the patients whose tumors weren’t removed by surgery, 12% responded to treatment. Specifically, 12% showed partial tumor shrinkage, while 4% had stable disease, that is, no growth or shrinkage.
According to Vaximm, this early result “suggests that, with further investigation, VXM01 in combination with [avelumab] could offer meaningful clinical benefit for this challenging patient population.”
For the patients who had surgery, survival times varied widely, ranging from 2.2 to 46.5 months.
The median time to disease progression was 2.7 months and median overall survival time was just under a year. These outcomes compare favorably with what’s typically seen in people with glioblastoma, where median survival time is usually just nine months or less, according to Vaximm.
Those who responded to treatment showed a decrease in tumor size, regardless of how big it was at the start. According to the company, this suggests the VXM01 vaccine could be effective for patients with larger tumors and those with early-stage or very small tumors.
Biomarker data from the trial indicate the VXM01/Bavencio combo induced an anti-tumor immune response as designed. Vaximm said the data warrant further testing of this combination in glioblastoma.
“We remain committed to advancing VXM01 as a key therapeutic candidate for the treatment of glioblastoma, other cancers and other diseases where VXM01 may have positive impact on treatment outcomes,” Hoefer said.