Sona Nanotech’s bold bet on cancer therapy: gold nanorods and the fight against “cold tumors”

For decades, cancer researchers have grappled with a stubborn challenge: the body’s immune system often fails to recognize and attack tumors. While immunotherapies like Merck’s Keytruda have revolutionized treatment, they still leave many patients behind. A small Canadian biotechnology firm, Sona Nanotech Inc (CSE:SONA, OTCQB:SNANF), is betting it can change that narrative with its pioneering use of gold nanorods to make tumors more vulnerable to the immune system’s assault.

Sona’s approach, called targeted hyperthermia therapy, is at the forefront of a wave of innovation aimed at unlocking the full potential of immunotherapy. The company’s preclinical studies have shown promise in combating colorectal cancer, melanoma, and triple-negative breast cancer—some of the most challenging forms of the disease. With its first human clinical trials slated for 2025, Sona’s efforts are drawing attention from oncologists and investors alike.

“Essentially, our therapy converts immunogenically cold tumors into hot tumors, making them more receptive to immunotherapy, which can then finish the job,” CEO David Regan told Proactive. “Once the immune system is activated, you can then apply standard immunotherapies, and the results can be remarkable.”

Gold nanorods: a microscopic marvel

At the core of Sona’s technology is a particle so small it can’t be seen with the naked eye. Gold nanorods, as they’re called, are engineered to precise dimensions to interact with light energy. When injected into a tumor and activated by a non-thermal laser beam, the nanorods heat up, killing cancer cells and causing the release of neoantigens—molecules that alert the immune system to the presence of a threat.

These neoantigens effectively serve as a biological alarm, prompting the immune system to mount a more aggressive response. Crucially, this process can convert “cold tumors,” which are typically invisible to the immune system, into “hot tumors” that spark immune activity. The therapy’s potential extends beyond the treated tumor, as it appears to trigger systemic responses capable of targeting metastatic cancer cells elsewhere in the body.

“When the immune system recognizes this new antigen, it doesn’t just target the treated tumor. It becomes capable of identifying and attacking the same antigen wherever it appears in the body,” Regan said.

“We’ve observed cases in preclinical studies where, after treating a tumor in one location, another tumor elsewhere in the body disappears. This suggests that the treatment is effectively creating immunity to the cancer.”

A breakthrough from academia

Sona’s technology originated in a university lab at St. Francis Xavier University. One of the company’s co-founders, Dr. Kulbir Singh focused on what was a conundrum: among PhD nanotechnologists, everyone knew that nanorods were the most functional because you could adjust their size—shorter, wider, longer—and therefore tune them for specific uses. However, everyone also knew their applications were limited because a toxic substance was required to elongate them. He set out to solve that problem.

From the beginning, he had the potential for cancer treatment in mind. The toxicity issue isn't a concern when using these nanorods in things like pregnancy tests or COVID tests. But if you’re injecting millions of them into humans, toxicity becomes a major concern.

Regan, who came to Sona from a finance background, was impressed by the existing research in the field. He could see that although many parts of the technology were proven, no one had yet brought all the elements together. But the board was looking for near-term revenue, and cancer research was a long road.

The team started doing some diligence with local physicians to determine which type of cancer to target first. “At that time, we understood that our treatment shrank tumors, but we didn’t fully appreciate the immunogenic, catalytic action that was being triggered,” Regan said. After meeting with a local surgical oncologist and describing the research, the researcher “rolled his eyes,” Regan laughed. “He said, ‘You guys have no idea what you have here, do you?’” the CEO recalled. 

“He opened our eyes to the immunogenic aspect of it. It turned out to be a fortuitous meeting, because his research over the past 35 years had led directly to this intersection of what we were doing.”

That physician, Dr Carman Giacomantonio, is now part of Sona’s executive team as the company’s chief medical officer.

Aiming for the clinic

Sona is preparing for its first-in-human trials, focusing initially on melanoma, a cancer that is easily accessible for light-based treatments. The company plans to conduct an early feasibility study outside Canada, with a broader trial planned domestically once feasibility is established.

“The goal here is to prove—within a small group of five to 10 patients—that we can replicate in humans the results we’ve observed in preclinical studies,” Regan said.

The company’s ambitions don’t stop at enhancing immunotherapy. By training the immune system to recognize and attack recurring cancer cells, Sona’s technology could lay the groundwork for a personalized cancer vaccine—a prospect that has long been considered the “holy grail” of oncology.

The investment case

For investors, Sona Nanotech presents both a high-risk and high-reward opportunity. Like many early-stage biotech firms, the company faces significant hurdles, including the inherent uncertainties of clinical trials and regulatory approvals. But, its innovative approach and promising preclinical data have already started to generate buzz.

The global cancer immunotherapy market, which market research firm Exactitude valued at more than US$92.11 billion in 2024, is expected to grow rapidly in the coming years, according to industry estimates. Sona’s technology, if successful, could carve out a niche in this lucrative market by enhancing existing therapies rather than competing with them directly.

A vision for the future

As Sona embarks on its clinical journey, the stakes are high, but so is the potential payoff. Beyond its implications for cancer treatment, the company’s technology exemplifies the possibilities of nanotechnology in medicine.

“This process can potentially reprogram the immune system,” Regan said. “When the immune system learns to recognize a new antigen, it doesn’t just target the treated tumor. It becomes capable of identifying and attacking the same antigen wherever it appears in the body.”

For now, all eyes will be on Sona’s clinical trials. If the company’s bet on gold nanorods pays off, it could usher in a new era of hope for cancer patients worldwide.