February 26, 2015
By Riley McDermid, BioSpace.com Breaking News Sr. Editor
Despite a marked lack of progress in new therapies to treat glioblastoma tumors, a type of brain cancer, the science is finally catching up and the next year will be an exciting one for new therapies and patients, Jeff Bacha, the president and chief executive officer of Del Mar Pharmaceuticals, told BioSpace this week.
Glioblastomas (GBM) are tumors formed from the supportive tissue of the brain. Highly malignant, they are usually found in the cerebral hemispheres of the brain, and reproduce quickly and they are supported by a large network of blood vessels. Because they often contain different types of cells, they are usually difficult to treat, leaving biotech companies frustrated at the still-high mortality rates for patients and lack of new products.
Bacha said that the drug that was approved, Avastin, for refractory patients in 2009 offers “some improvement in quality of life, but doesn’t improve survival.” Prior to that, Temodar was approved as front-line therapy, and although it’s more convenient for patients and has fewer side-effects than the drugs it replaced, survival outcomes were really no better. The median survival for GBM patients is still well under two years.
“That said, a lot of the recent excitement in the cancer field has been focused on immunotherapies. Immunotherapy or ‘immuno-oncology’ centers on the principal of harnessing our own immune system to destroy tumor cells,” he told BioSpace. “Science is finally allowing us to scratch the surface of this opportunity and it holds huge promise. “
But Bacha said Del Mar is very excited about their new GBM drug, VAL-083, which is a chemotherapy that has the potential to offer a real solution. There are caveats for the field in general, though, said Bacha.
“An important thing to keep in mind is that a key component of an immunotherapy regimen is an active chemotherapy, so it’s really ‘chemo-immunooncology’ that we’re talking about as the multi-modal approach that could truly change the landscape of cancer care. That’s where VAL-083 comes in,” he said.
Chemotherapy causes cancer cell-death through apoptosis, which can increase tumor antigen presentation or decrease expression of immune checkpoint molecules in the tumor micro-environment, potentially benefiting the activity of an immunotherapy, said Bacha. He added that because mmunotherapies are also, in general, pro-inflammatory, they may render tumors more susceptible to traditional chemotherapies.
“What’s exciting for DelMar is that VAL-083 should be an ideal agent of choice for strategically integrating with potential immune-based therapies,” he told BioSpace.
“You see, while there is evidence of synergy between chemotherapy and immunotherapy, it’s not that simple. The interaction between chemotherapy and the immune system is complex and could actually be antagonistic in some cases,” said Bacha. “A chemotherapy could actually suppress the anti-tumor immune response, by decreasing lymphocytes or inhibiting lymphocyte function.”
He said that based on the NCI’s experience Del Mar’s own clinical trial, the dose-limiting toxicity with VAL-083 will be myelosuppression, but it is platelet related rather than lymphocyte related, which means the mechanism should not conflict with the activity of an immunotherapy.
“This is particularly exciting in GBM where the majority of patients are resistant to the available chemotherapies,” said Bacha. “Our data shows that VAL-083’s unique anti-tumor mechanism works where current chemotherapies fail and may be more potent where they are active. So, we’ve got an exciting drug candidate that should be really well positioned as the era of chemo-immunooncology evolves.”
BioSpace Temperature Poll
Analyst Mark Schoenebaum, a biotech and pharmaceuticals analyst and medical doctor for ISI Group Evercore, has been running a Best Hair in Biopharma contest for several months now. So far, the candidates are Bristol-Myers Squibb Company‘s John Elicker, Receptos’ Chief Executive Officer Faheem Hasnain, Celgene‘s Vice President of Investor Relations Patrick Flanigan and Acorda Therapeutics’ Ron Cohen.
We want to know what our BioSpace community thinks: Who do you believe actually has the Best Hair in BioPharma?
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