By Janet Goetze
For the Hollywood Star News
Providence Cancer Center researchers are reporting a “gratifying response” from a clinical trial using an antibody to boost the body’s ability to fight late-stage cancer.
The phase 1 trial results, recently published in the journal Cancer Research, showed tumors in 12 of 30 patients shrank. Also, all patients experienced improved immune response and only mild or moderate side effects, the researchers said.
The Providence team performed the first study on people using an antibody that binds and helps activate OX40, a protein expressed on the surface of T cells, a type of white blood cells that play a role in immune response.
“The idea being that enhancing OX40 and other T-cell pathways will increase the body’s ability to fight the cancer,” said Dr. Brendan Curti, director, Genitourinary Oncology Research and Biotherapy Programs in the Earl A. Chiles Research Institute at the cancer center.
The trial was for patients with widespread cancer who had failed standard treatments of surgery, chemotherapy and radiation, Curti said. The 30 participants had a variety of cancers, including melanoma, colon, pancreatic and kidney cancers.
The side effects experienced included brief changes in blood counts and some mild flu-like symptoms, Curti said.
In addition to the antibody, each trial patient received a tetanus vaccine or a substance called keyhole limpet hemocyanin or KLH. Curti said the researchers figured if they gave each substance with OX40, then measured an immune response, they could determine what the immune system is doing.
“The OX40 revved up the cells that can have an anti-tumor effect without boosting the cells that normally shut down an immune response,” Curti said. “The fact that we could measure a consistent immune response across all of these 30 patients was surprising and not often reported with other immune boosters given to cancer patients.”