“Cancer vaccine” heads to human trials

Researchers at Stanford are battling tumors in a new clinical trial using the body’s own immune system to seek and destroy cancer cells-and it seems to be working.

The so-called “cancer vaccine” currently being tested by researchers at the Stanford University School of Medicine doesn’t need to target specific tumor cells. Nor does it put the patient’s immune system into overdrive or require costly re-engineering of immune cells to attack cancer like other immunotherapies. Instead, it combines small pieces of DNA that amplify receptors on T-cells in the tumor necrosis factor (TNF) cytokine with an antibody that reactivates T-cells that have been suppressed by the cancer. One of the vaccine components is already approved for use in humans and the other is being tested in clinical trials unrelated to this vaccine, according to a statement from the university.

Rather than being administered as a traditional vaccine to prevent the development of a disease, the Stanford team’s treatment is then injected directly into tumors. Once the T-cells within the tumor do their job, some then leave the previously cancerous cells in search of additional tumors to destroy.

The team published their research in Science Translational Findings and is now moving from animal to human trials. Ronald Levy, MD, chief of oncology and professor at Stanford University and senior author of the report, said the treatment harnesses the power of the body’s own immune system to fight tumors.

“Immune stimulating agents are injected directly into one tumor site and hopefully this triggers an immune response against the tumor throughout the body,” he said.

In initial animal studies, the research team injected the vaccine into one of two tumors implanted into 90 mice. Eighty-seven of the mice were cured completely, and two of the three whose tumors persisted showed improvement after a second treatment. The vaccine also showed promising results for mice with breast, colon, and melanoma tumors, according to the study.

“This may add a practical and safe form of immunotherapy that can be interdigitated with other forms of cancer therapy,” Levy said.

The research team is now working on human trials, with plans to perform the first test on about 15 patients with low-grade lymphoma with a possible second trial group planned for later this year. Levy said in a statement that he envisions the vaccine being used in solid tumors before surgical removal to prevent recurrence caused by unidentified metastases or cancer cells left behind that could develop into future tumors. He said the vaccine could be used on a wide variety of tumors, and anticipates that it could be used for a wide variety of tumors as long as there is an injectable site. If the trials go well, Levy said in the statement that the treatment cold be available in one to two years and be more cost-effective than current immunotherapies being investigated.