Positive results from ULCA's Phase 1 dendritic cell vaccine trial in glioblastoma

A novel brain tumor vaccine clinical trial study demonstrates a longer survival time in patients with glioblastoma, according to findings being presented at the 79th Annual Scientific Meeting of the American Association of Neurological Surgeons (AANS) in Denver.

Glioblastoma, or malignant glioma, is the most common malignant brain tumor, and also the most deadly, because it is very resistant to treatment. This is the type of brain tumor that claimed the life of the late Senator Ted Kennedy. In general, current treatments have not yielded significant increases in survival rates, which is why research into novel therapies is so crucial.

Researchers at the University of California, Los Angeles, analyzed the efficacy of a Dendritic Cell vaccine in patients with glioblastoma. The results of this study, Vaccination with Dendritic Cells Pulsed with Autologous Tumor Lysate is Associated with Prolonged Overall Survival compared to Dendritic Cells Loaded with Tumor-Associated Antigens: Results from Prospective Phase 1 Clinical Trials, will be presented by Isaac Yang, MD, 11:41-11:55 am, Monday, April 11. Co-authors are Won Kim, MD, Arthur Chou, MD, PhD, Brendan Fong, BS, Michael Safaee, BS, Robert M. Prins, PhD, and Linda M. Liau, MD, PhD. Dr. Yang will be presented with the Ronald L. Bittner Award on Brain Tumor Research for this research.

Dendritic cell vaccines for brain tumors such as glioblastoma use the patient's own cancer cells and proteins to stimulate an immune response against the tumor. This form of "personalized medicine" creates a unique vaccine for each glioblastoma patient. The immunotherapy approach using a vaccine allows the body's own immune system to fight the tumor by recognizing that it doesn't belong.

A total of 26 patients with either recurrent or newly diagnosed glioblastoma were enrolled into two Phase 1 clinical trials for dendritic cell vaccine therapy at UCLA. Autologous tumor lysate-pulsed vaccine treated patients were compared to glioma associated-antigen pulsed dendritic cell vaccinated patients for time to tumor progression (TTP) and overall survival (OS) through a Kaplan Meier Analysis. The following results were noted:

•Tumor lysate-pulsed DC vaccine treated patients had a significantly longer overall survival when compared to patients who received DCs pulsed with specific tumor peptides (35.5 versus 17.5 months;

•TTP in the tumor lysate cohort was 27.4 +/- 23.5 months. In the peptide-treated group the TTP was 11.6 +/- 10.5 months. This difference in TTP was not statistically significant

"These findings suggest that overall survival may improve in patients treated with tumor lysate pulsed DC vaccination compared to those who received dendritic cells pulsed with specific glioma-associated antigens. The improvement in overall survival may suggest that tumor lysate DC vaccination has the potential to induce a more heterogeneous and diverse immune response against glioblastoma. Having multiple avenues of attack on gliomas may be more effective than only attacking a few targets on these glioblastomas. Our preliminary results indicate that this type of immunotherapy may offer hope for improved outcome in patients with this devastating brain tumor and warrants further study on a larger patient group," said Dr. Yang. Currently, glioblastoma vaccine clinical trials are being performed at several academic neurosurgery centers, such as UCLA.