​DelMar Pharmaceuticals, a biopharmaceutical company focused on developing and commercializing proven cancer therapies in new orphan drug indications, announced updated clinical data from its Phase 1/2 clinical trial of VAL-083 (dianhydrogalactitol) in patients with refractory glioblastoma multiforme (GBM), the most common and deadly form of human brain cancer.

Results from DelMar's clinical study titled, "Phase 1/2 study of dianhydrogalactitol in patients with recurrent malignant glioma," (abstract no. 2023) were presented during the Central Nervous System Tumor session at the 2015 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, IL.

Jeffrey Bacha, DelMar's president & CEO, stated, "The patients enrolled in the dose-escalation portion of our clinical trial were heavily pre-treated having failed both front-line therapy with temozolomide and, in most cases, also failing second-line Avastin and one or more salvage therapies prior to treatment with VAL-083. This population has an extremely poor prognosis.  Since none of the patients' tumors were re-resected prior to VAL-083 treatment, we expected – and observed – near-term progression in most patients. However, we also considered the potential impact on patient survival based on slowing the growth of the tumor even with limited treatment."

Mr. Bacha added, "The overall survival demonstrated at the higher doses in our clinical trial with only two cycles of treatment is clinically meaningful in comparison to published outcomes in this patient population. We consider these results to be positive and supportive of the further development of VAL-083 as a potential new therapy for GBM patients who have failed other available treatments." 

The study was designed to assess the safety and tolerability of patients receiving VAL-083 on days 1, 2, and 3 of a 21-day cycle. Tumor response is assessed according to RANO criteria prior to every other 21-day treatment cycle, and patients exhibiting stable disease or tumor regression at the first scan following treatment were allowed to continue treatment with VAL-083 at the dose defined for their cohort. Determination of maximum tolerated dose (MTD) is based on a 3+3 design. Currently, 30 GBM patients have been enrolled across 8 dose cohorts ranging from 1.5 to 50mg/m2/d.

All GBM patients enrolled in DelMar's Phase 1/2 clinical trial failed prior treatment with standard front-line (temozolomide plus radiation) and 92 percent also failed Avastin. Seventy-seven percent also failed one or more courses of additional salvage therapy beyond temozolomide and Avastin prior to VAL-083. Patients were not re-resected prior to treatment with VAL-083 and therefore have a growing GBM tumor at the time of enrollment in the DelMar clinical trial. O6-methylguanine methyltransferase (MGMT) expression was characterized for patients whose data or tissue blocks were available for analysis. All patients whose tumors were characterized had an unmethylated MGMT promotor, which is correlated with poor patient outcomes to currently available therapies.

Source: Delmar Pharmaceuticals