Celldex's Brain Cancer Vaccine Shows Promising Interim Results
By C. Rajan, contributing writer
New Jersey-based biotech company Celldex Therapeutics has reported the positive interim results from a Phase 2 study of its novel brain cancer immunotherapy vaccine, rindopepimut, in patients with recurrent glioblastoma. The vaccine was found to extend the survival of glioblastoma patients who have relapsed after surgery, chemotherapy, and radiation, by a statistically significant 3.2 months.
The company presented the data at the 4th Quadrennial Meeting of the World Federation of Neuro-Oncology.
Rindopepimut (Rintega) is an investigational cancer immunotherapy vaccine that targets EGFRvIII, a specific mutation found on tumor cells. Since EGFRvIII is specific to tumor cells, the vaccine can selectively kill tumor cells without harming the healthy ones.
The Phase 2 study (ReACT) evaluated rindopepimut in patients with EGFRvIII-positive glioblastoma (GBM). The results showed promising improvement in patients with recurrent glioblastoma, including groups both naïve and refractory to the chemotherapy drug, bevacizumab (Avastin, Genentech/Roche). The 125 patients in the study were divided into three groups, and the vaccine was found to be safe and well-tolerated in all three groups.
Patients treated with rindopepimut, along with bevacizumab survived for a median of 12 months, compared to 8.8 months for those getting bevacizumab alone. The vaccine also helped to slow down the progression of the tumors, with 27 percent of the patients on rindopepimut + bevacizumab showing progression free survival after six months of treatment, compared to 11 percent of patients in other groups.
Glioblastoma is the most aggressive form of brain cancer, and patients typically have median survival of about only 12 to 15 months with treatment. About 30 percent of patients with glioblastoma have the EGFRvIII-positive type, and have a much poorer prognosis than patients with other types of glioblastoma.
According to Celldex, an estimated 3,000 patients in the U.S. and 6,000 in Europe, have glioblastoma with an EGFRvIII mutation, and most of them experience a recurrence of the cancer even after treatment.
"The interim data presented today are extremely encouraging and continue to add to an impressive and consistent data set for rindopepimut across multiple studies and stages of disease," said Thomas Davis, M.D., EVP and CMO of Celldex. "We believe these interim data are clinically important to patients with recurrent glioblastoma and, if the final data remain consistent, we intend to discuss the significance of these findings with regulatory authorities."
Rindopepimut is currently also being studied in an international Phase 3 study (ACT IV) in newly diagnosed glioblastoma patients, which is expected to produce interim data in mid-2015.