By saturating cancerous tissues with nanoparticles that covert light into heat—tiny shells, made of gold and silicon—clinicians were able to destroy prostate tumors with laser precision in a first-in-human trial.
After one year, 14 out of the 16 treated lesions tested negative for signs of cancer, according to procedure developer Nanospectra Biosciences.
The company’s gold-silica particles, dubbed AuroShells, are designed to absorb wavelengths of light that approach the infrared spectrum but are still able to pass through tissue. When charged up by a laser beam, they release heat energy that ablates the immediately surrounding tumor cells, allowing a tightly controlled treatment that aims to spare the adjacent healthy tissue.
Administered in an infusion, the shells circulate freely in the bloodstream before collecting in prostate tumors. With a diameter of about 150 nanometers, the biocompatible particles are too big to pass from the body’s blood supply into the tight spaces within healthy tissues, according to Nanospectra, but they can penetrate a tumor’s comparatively leaky and malformed vasculature.
“Jennifer West, bioengineer at Duke University, and I initiated development of the gold-silica nanoshells nearly 20 years ago,” said Nanospectra co-founder Naomi Halas, a professor of biophysics at Rice University.
“By varying the thickness of the gold outer shell, we demonstrated that we could tune the nanoshells to interact with specific wavelengths of light,” Halas said in a statement. “By tuning the resonance beyond the visible and into the near-infrared region, we opened the door to a wide range of applications in nanomedicine.”
The results were published in the Proceedings of the National Academy of Sciences. Conducted at the Icahn School of Medicine at Mount Sinai, the study also met its primary safety endpoint with no grade 3 or higher adverse events within 90 days of the procedure.
“We are encouraged by the clinical success of our feasibility study to date and look forward to the initiation, potentially next month, of the pivotal study with an expected cumulative treatment population of 100 subjects,” said Nanospectra CEO David Jorden.