On November 17, 2022, results from a phase 3 trial of DCVax-L, an immunotherapy for glioblastoma patients, were published in the Journal of the American Medical Association (JAMA) Oncology.
While the results of the DCVax-L trial may eventually provide a treatment option for GBM patients, DCVax-L has not yet been approved by the FDA, so the treatment is not widely available to patients. It is also not known if or when it will receive approval from the FDA.
The data are highlighted in this article below.
Considerations
The ABTA is very supportive of immunotherapy approaches for treating brain tumors. As with any trial, the data must be considered carefully. When viewing the results of the DCVax-L trial, there are some important points to consider. First, changes were made to the original trial design and study endpoints mid-way through the trial that may have impacted interpretation of the data.
Second, the control arm of the study only included external controls, meaning that the researchers used data from control arms from other clinical trials. Conventional clinical trials leading to FDA approval usually require that the outcomes of a new treatment are directly compared to a group of patients randomized to the standard treatment, within the same trial. Therefore, this approach of external controls will need considerable external and independent vetting, before declaring these results as providing top-level proof of effectiveness.
When reviewing the results below, it is important to take these points into consideration.
What is Glioblastoma (GBM)?
Glioblastoma (GBM) is the most common primary brain cancer. GBM is invasive and infiltrative and is therefore impossible to completely resect with surgery. Nearly all patients experience recurrence, often within seven to eight months. Median overall survival for GBM patients is 15-17 months from diagnosis, or eight months from recurrence, and fewer than 5% of patients are expected to survive five years after diagnosis.
The aggressiveness of this cancer demonstrates that more treatment advances are critical.
Despite many clinical trials, no new systemic therapies have shown significant benefit for GBM patients since the approval of Temozolomide and radiation in 2005. Since then, the only treatment that demonstrated improved outcomes for GBM patients is Tumor Treating Fields (TTF/Optune), a medical device worn on the head, which received FDA approval in 2019.
What is the treatment DCVax-L?
Developed by Northwest Biotherapeutics, the DCVax-L treatment is a personalized vaccine created from a patient’s own dendritic cells (a type of immune cell that helps the immune system recognize and attack cancer cells). The process of making this vaccine takes several weeks to a few months.
Once patients have recovered from surgery and completed standard therapy, they begin receiving their personalized vaccine along with the standard of care temozolomide. They can also get additional doses of their vaccine over two years if recommended.
What were the results from the trial?
The trial included 331 newly diagnosed and recurrent GBM patients at 94 sites in four countries.
The publication reported that adding DCVax-L to existing treatments increased overall survival for newly diagnosed GBM patients by 2.8 additional months on average, compared with patients that did not receive the vaccine; 13% of those patients survived at least five years.
For recurrent GBM patients, overall survival increased to 13.2 months on average from the time of recurrence, compared to 7.8 months on average among the external control group; 11.1% of recurrent GBM patients treated with the vaccine were still alive at 2.5 years compared to 5.1% of patients from the external control group.
The ABTA encourages all patients to talk to their care team about all treatment options and clinical trials available to find the best course of treatment for their tumor and their circumstances.
To learn more about clinical trials, view the ABTA’s Clinical Trials brochure or visit the Clinical Trials resource page.
Jessie Schlacks
Jessie is Managing Editor of the bi-monthly e-newsletter MindMatters. Submit story ideas or questions to jschlacks@abta.org.