Autologous HSPPC-96 vaccine clinically beneficial for GBM patients

Study results from a Phase II multicenter clinical trial tracking the impact that autologous heat shock protein-peptide vaccine (HSPPC-96) has on recurrent glioblastoma multiforme (GBM) patients showed that such a vaccine may be clinically beneficial. Researchers shared those results today at the 80th Annual Scientific Meeting of the American Association of Neurological Surgeons (AANS) in Miami, noting that the further testing against currently approved therapies for GBM could provide further insight into the potential use of this vaccine.

A need for new adjuvant treatments for recurrent GBM patients undergoing surgical resection is well established. HSPPC-96 — made from the GBM patient's individual tumor containing glycoprotein-96 associated with cancer-specific antigenic peptides — has already been successfully tested in a Phase I clinical trial for recurrent GBM patients. This Phase II multicenter clinical trial was designed to evaluate overall survival post-operatively after HSPPC-96 vaccination. Eligibility criteria included diagnosis of recurrent GBM; KPS>70; and radiographic confirmation of >90 percent resection. The study results of A Phase 2 multicenter trial of autologous heat shock protein-peptide vaccine (HSPPC-96) for recurrent glioblastoma multiforme (GBM) patients shows improved survival compared to a contemporary cohort controlled for age, KPS and extent of resection will be presented by Andrew T. Parsa, MD, PhD, FAANS, 10:15-10:29 a.m., on Tuesday, April 17. Co-authors are Courtney Crane, PhD; Seunggu Han, MD; Valerie Kivett; Anne Fedoroff, RN; Nicholas Butowski, MD; Susan Chang, MD; Michael Prados, MD; Jennifer Clarke; Mitchel Berger, MD, FAANS, FACS; Michael McDermott, MD, FAANS; Manish Aghi, MD, FAANS; Andrew Sloan, MD, FAANS; and Jeffrey Bruce, MD, FAANS, FACS.

More than 40 patients were treated and the population evaluated for efficacy had a median KPS of 80 and median age of 53. The vaccine was well tolerated, with no related grade 3 or grade 4 toxicities. The median survival for evaluable patients was 47.6 weeks (25 percent-75 percent percentiles = 37.1-60.7) and six-month survival was 93 percent. HSPCC-96 treated patients lived significantly longer than 86 consecutive patients not enrolled on the HSPPC-96 clinical trial, but treated with alternative therapies during the study period at UCSF. Like the HSPPC-96 treated patients, the control patients also underwent >90 percent resection of recurrent GBM and had a KPS>70. The median overall survival for these patients was only 32.8 weeks with a six-month survival of 68 percent, compared to a median survival of 47.6 weeks and a six-month survival rate of 93 percent for the vaccine treated group (p<0.01).

The survival data available up to now indicates that the HSPPC-96 vaccine may help patients treated with the therapy live longer, and suggests a possible clinical benefit to those suffering from recurrent GBM. In addition, the researchers note that the HSPPC-96 results are superior to similar surgical populations identified in the literature as well as a contemporary cohort controlled for age, KPS and extent of resection. These results provide the impetus for further testing against presently approved therapies for recurrent GBM patients. The Cancer Therapy Evaluation Program (CTEP) of the National Cancer Institute (NCI) recently approved, on an expedited basis, a study concept to test HSPPC-96 vaccine in a large randomized Phase 2 trial in combination with bevacizumab in patients with surgically resectable recurrent GBM. The study, which is still in the early planning phases, will be sponsored by the Alliance for Clinical Trials in Oncology (ACTION), a newly formed NCI cooperative group.

According to the lead investigator Dr. Andrew Parsa, "Cancer vaccines for brain tumor patients offer the hope of a highly specific therapy, with minimal toxicity. The multiple antigen, patient-specific approach of the HSPPC-96 vaccine is ideally suited for recurrent GBM patients who undergo surgical resection. Based on the present study we plan to move forward with a more definitive, randomized trial evaluating the efficacy of HSPPC-96 in combination with bevacizumab compared to bevacizumab alone in recurrent GBM patients undergoing surgical resection."