Novel Cancer Treatment Shows Promise
A novel immunotherapy combination appears safe for use in patients with a type of blood cancer called non-Hodgkin’s lymphoma. Not only that, but half of the 22 people enrolled in an early clinical trial of the therapy had a positive response, and about one-third went into complete remission from their cancer.
The therapy combines Hu5F9-G4 (an experimental antibody developed by researchers at Stanford) and a commercially available anti-cancer antibody called rituximab.
“It was very gratifying to see how the treatment was well-tolerated and showed a clinically meaningful response,” says Ranjana Advani, MD, professor of medicine at Stanford. Advani is the lead author of a paper describing the results of the phase-1 trial that was published in The New England Journal of Medicine.
Some patients showed signs of a transitory anemia or reactions at the injection site, but there were few other significant side effects to the treatment, according to the paper.
Although there are many things that can kill cancer cells, the real test of a therapy is whether it can kill the cancer cells without harming normal cells. Advani says she was particularly pleased that the researchers observed only minor side effects in the participants.
How the Combination Works
In 2010, researchers led by Irving Weissman, MD, director of the Stanford Institute for Stem Cell Biology and Regenerative Medicine, showed that the CD47 protein that covers nearly all cancer cells acts as a “don’t eat me” signal to immune cells called macrophages.
Weissman and his colleagues later developed the Hu5F9-G4 antibody that blocks the CD47 protein, prompting macrophages to engulf and devour cancer cells.
For this clinical trial, participants were administered a combination of Hu5F-G4 and the rituximab antibody that has been shown to amplify positive “eat me” signals.
The antibody combination was used to treat people with two types of non-Hodgkin’s lymphoma: diffuse large B-cell lymphoma and follicular lymphoma.
“It’s very exciting to have a potentially new class of immunotherapy like this,” says Advani. “For the first time we have an antibody that activates macrophages against cancer and appears to be safe for use in humans.”
A Personal Trial
Clinical trial participant Michael Stornetta, a retired Santa Rosa businessman who said he had never previously been sick with anything worse than colds, flus, and the usual childhood maladies, was hit with follicular lymphoma over five years ago. He said that after attempting multiple therapies with “varying degrees of success,” he was referred to the Hu5F9-G4 trial at Stanford.
In October of 2017, he drove with his wife and son to Stanford to view the first scans that would reveal whether the experimental treatment was working. The scans showed that his cancer was significantly reduced. By strange coincidence, the very day he learned that he had lost his house in a devastating wildfire, he also learned that the treatment was working.