The approval was based on findings from the phase 3 EF-14 trial.
The FDA has expanded the indication for Optune (NovoTTF-100A System) in combination with Temodar (temozolomide) as a treatment for patients with newly-diagnosed glioblastoma multiforme (GBM) following surgery, chemotherapy, and radiation therapy, based on findings from the phase 3 EF-14 trial.
In a full analysis of 695 patients enrolled in the phase 3 study, the median overall survival (OS) was 19.4 months compared with 16.6 months with Temodar alone. Additionally, progression-free survival (PFS) was improved by approximately three months, according to the FDA.
"Patients newly diagnosed with this challenging and aggressive form of brain cancer now have another treatment option available," William Maisel, MD, MPH, acting director of the Office of Device Evaluation in the FDA's Center for Devices and Radiological Health, said in a statement. "While the treatment is not a cure, it can increase survival by several months."
Optune is a portable, noninvasive, battery-operated device that attaches to the patient's head to deliver tumor treating fields to the brain. The device appears to slow and reverse tumor growth by inhibiting mitosis during metaphase, anaphase and telophase.
Interim results from the EF-14 study were presented at the 2014 Society for Neuro-Oncology Annual Meeting. Based on an early assessment of 315 patients in the study, an Independent Data Monitoring Committee recommended that the study should be stopped early to allow those in the control arm to cross over to receive Optune with Temodar.
In the phase 3 study, patients were randomized in a two-to-one ratio to receive adjuvant therapy with Optune plus Temodar or Temodar alone. Patients were enrolled following completion of standard radiotherapy with concomitant Temodar. At the interim analysis, 210 patients were treated with the combination versus 105 with Temodar alone. The primary endpoint of the study was PFS, with OS as a secondary outcome measure.
Patient characteristics were well balanced between the two arms. The median age of patients was 57 and 58 years, the tumor was resected for 89 percent and 90 percent, and 39 percent and 41 percent had MGMT promoter methylation, in the combination and control arms, respectively. Karnofsky performance status was 90 percent in both groups.
After a minimum follow-up of 18 months, the risk of progression or death was reduced by 37 percent with the addition of Optune to Temodar. The median PFS was 7.1 months with the combination compared with 4.0 months with Temodar alone.
At this analysis, the median OS with the combination was 19.6 versus 16.6 months with the single-agent. The estimated 24-month OS rate was 43 percent with the Optune and Temodar combination versus 29 percent with Temodar alone.
Skin irritation occurred in 45 percent of patients. Severe seizures occurred at a frequency of 7 percent in both groups.
"Today marks a significant milestone in glioblastoma treatment," said Elizabeth Wilson, President and CEO of the American Brain Tumor Association, Chicago. "For a disease for which there are few treatment options, Optune offers new hope for extending survival from the start of treatment."
The FDA initially approved Optune in 2011 as a treatment for patients with GBM that recurred or progressed after chemotherapy. With this expanded indication, the system can be used as part of a standard treatment for GBM before the disease progresses.
Stupp R, Wong E, Scott C, et al. Interim analysis of the EF-14 trial: a prospective, multicenter trial of NovoTTF-100A together with temozolomide compared to temozolomide alone in patients with newly diagnosed GBM. Presented at: 19th Annual Meeting of the Society for Neuro-Oncology; November 13-16, 2014: Miami, FL.