A brain cancer study on rats using Theralase Technologies Inc’s (CVE:TLT) lead photo dynamic therapy (PDT) technology could have positive implications for human cancer victims.
Theralase’s laser technology activates photo dynamic compounds (PDCs) using a specific wavelength of light. The light’s role in the process is to stimulate the PDCs, once inside the cancer cell, to produce a reactive form of oxygen that kills the cancer cell from the inside out. There is no toxicity involved in the treatment and no side effects.
The latest study demonstrated the ability of Theralase’s lead PDT, Rutherrin (a combination of Theralase’s Ruthenium-based PDC and transferrin, an iron-bounding blood plasma glycoprotein), to increase survival significantly for a very aggressive form of brain cancer, known as glioblastoma multiforme (GBM).
GBM is the most common and aggressive form of cancer that begins within the brain, and kills more than 85% of its victims within five years of diagnosis.
Now, the effect has only been demonstrated on one rat, and rats are not humans, but rodents are often used in cancer studies because, being mammals, they share many similarities to humans in body structure and organ functions.
Untreated rats with GBM typically die within four days or so once the disease becomes detectable via magnetic resonance imaging, and in similar tests this had been stretched to eight days when treated with a PDC (but not one of Theralase’s).
In the Theralase test, the rat treated with Rutherrin is still alive, 31 days after being infected.
The Canadian company said a two-day median survival in rats with GBM would be equivalent to a three-month survival in humans. Extrapolating that, the 31 days (and rising) of survival of the plucky rate is equivalent to 81 months in humans.
The current median survival in humans with extensive treatment is in the region of 14.1 months.
Theralase said future experiments are planned to optimize the treatment, hopefully resulting in ever better efficacy.
“The data presented clearly demonstrates that the PDC Rutherrin (TLD-1433 + transferrin) is able to cross the blood brain barrier, an immune privileged site, and be absorbed preferentially by tumour tissue through the transferrin receptor (15.7 times higher uptake in GBM versus healthy brain tissue),” said Arkady Mandel, Theralase’s chief scientific officer.
“The data also indicates a significantly higher concentration of drug in tumour compared to normal tissue at between four hours and 24 hours post injection, suggesting that an optimal time to activate the PDC would be between these two time points. This latest research will allow us the ability to plan additional experiments to optimize the treatment methodology, prior to designing a Phase Ib human clinical study for patients inflicted with GBM,” Mandel added.
Roger Dumoulin-White, president and chief executive officer of Theralase said the PDT technology’s ability to destroy a wide range of cancer targets never ceased to amaze the company.
“We have shown a very high kill rate of non-muscle invasive bladder cancer (NMIBC) pre-clinically, and now we have demonstrated a similar response in brain cancer. It is interesting to note that Theralase has employed different PDC installation methods (intravenous versus intravesical) and different activation wavelengths (NIR versus green) in the two cancers demonstrating the versatility of this technology to be applied across a wide range of cancers,” Dumoulin-White said.
“Human clinical trials for NMIBC are around the corner and with some optimization steps, it seems that brain cancer clinical trials are not far behind. I look forward to introducing this technology to the world commercially in the not too distant future,” he added.
Story by ProactiveInvestors