DelMar Pharmaceuticals announced it has received Institutional Review Board (IRB) approval to conduct its pivotal Phase 3 Study in Temozolomide-Avastin (bevacizumab) Recurrent GBM (STAR-3).
"IRB approval is an essential step in initiating patient enrollment in our Phase 3 trial," stated Jeffrey Bacha DelMar's chairman & CEO. "We are pleased to remain on track to open enrollment in this trial at leading centers in the United States. Based on our research, we believe that VAL-083 offers significant potential as a new therapy for GBM patients who currently have no viable treatment options."
Under FDA regulations, Institutions Review Boards (IRBs) are required to review all human subject research to ensure that the rights and welfare of human subjects are protected at all times. To accomplish this purpose, IRBs are comprised of physicians and research administrators with the authority to approve, require modifications to, or disapprove research. The VAL-083 STAR-3 GBM trial and all pertinent study related materials were critically examined by Schulman IRB, the leading independent institutional review board, and approved without any modifications.
DelMar's VAL-083 STAR-3 GBM trial is an adaptive design, randomized, controlled pivotal Phase 3 clinical trial in patients with glioblastoma multiforme (GBM) whose disease has progressed following prior treatment with temozolomide and bevacizumab.
A total of up to 180 eligible patients will be randomized at approximately 25 centers in the United States to receive either the investigational drug (VAL-083) or "investigator's choice salvage therapy" as a contemporaneous control, in a 2:1 fashion. Up to 120 eligible patients will be randomized to receive intravenous VAL-083 at 40 mg/m2 on days 1, 2, and 3 of a 21-day treatment cycle, for up to 12, 21-day treatment cycles or until they fulfill one of the criteria for study discontinuation. Up to 60 patients will be randomized to "investigator's choice" control, limited to temozolomide, lomustine, or carboplatin, until they fulfill one of the criteria for study discontinuation.
In both study arms, interval medical histories, targeted physical exams, neurologic evaluations, complete blood counts, and other laboratory and safety assessments will be performed approximately every 21 days while receiving treatment. Tumor assessments are to be performed approximately every 42 ± 7 days while remaining on study. The study is estimated to last less than two years from initiation.
The primary endpoint of the trial is overall survival. The statistical design between the two arms of the study is 90% power, and is proposed to include an interim analysis at 50% events for futility with O'Brien-Fleming superiority boundary and non-binding, gamma (-5) futility boundary.
VAL-083 (dianhydrogalactitol) is a DNA-targeting agent that introduces interstrand DNA cross-links at the N7-position of guanine leading to DNA double-strand breaks and cancer cell death. VAL-083 has demonstrated clinical activity against a range of cancers including GBM in historical clinical trials sponsored by the U.S. National Cancer Institutes.
VAL-083 has been granted an orphan drug designation by the U.S. FDA Office of Orphan Products for the treatment of glioma, medulloblastoma and ovarian cancer, and in Europe for the treatment of malignant gliomas.
DelMar's recent outcomes in Phase 1-2 clinical trials suggested that VAL-083 may offer a clinically meaningful survival benefit for patients with recurrent GBM following treatment with both TMZ and bevacizumab. A well-tolerated dosing regimen of 40mg/m2/day on days 1, 2, and 3 of a 21-day cycle was selected for study in subsequent GBM clinical trials.
Glioblastoma (GBM) is the most common and aggressive primary brain cancer. Current standard of care includes surgery, radiation and treatment with temozolomide (TMZ), however nearly all tumors recur and the prognosis for recurrent GBM is dismal. Most GBM tumors have unmethylated promoter status for O6-methylguanine-DNA-methyltransferase (MGMT); a validated biomarker for TMZ-resistance. Second-line treatment with anti-angiogenic agent bevacizumab has not improved overall survival (OS) and 5-year survival is less than 3%.