A vaccine that uses cancer cells against themselves significantly slows the progress of a deadly form of blood cancer, a researcher said at the annual meeting of the American Society of Clinical Oncology (ASCO).
In patients with follicular non-Hodgkin's lymphoma, the vaccine -- dubbed BiovaxID -- nearly doubled the time before the disease recurred, compared with a control drug, according to Dr. Stephen Schuster of the University of Pennsylvania School of Medicine in Philadelphia.
In the small trial -- 76 patients got the vaccine and 41 did not -- the vaccine extended time to relapse by more than a year: 44 months versus 30 months.
"The problem with this kind of lymphoma is that chemotherapy doesn't actually cure anybody," said ASCO president Dr. Richard Schilsky of the University of Chicago Medical Center, who was not involved in the study.
"They all go into remission with chemotherapy but they all relapse," Schilsky said. "Each time you use chemotherapy, the remission lasts less time and eventually they just become refractory."
So, he said, "The longer you can keep them in remission the better."
The therapeutic vaccine is tailored to each patient's cancer and given with a drug that stimulates the immune system, Schuster said during the annual ASCO meeting.
"We've now moved into an era where we can safely use a patient's immune system to effectively fight follicular lymphoma and enhance the response to conventional chemotherapy," Schuster said in a statement.
The key outcome is that in a "very select group of patients," the approach significantly lengthens the time before cancer returns, according to Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, who was not involved in the study.
But Lichtenfeld said it has taken many years to reach this point, with many false steps along the way. "Maybe we're finally learning something," he said, " that will translate hope to reality."
There are about 65,000 new cases of non-Hodgkin's lymphoma diagnosed each year in the United States, and despite aggressive chemotherapy and recent advances in therapy, the disease is almost uniformly fatal.
In the follicular form of the disease, 90 percent of patients die within seven years of diagnosis.
The vaccine itself is made by extracting cells from lymph nodes and identifying a cancer marker -- an "idiotype" -- that is unique to each patient, Schuster said. This idiotype is then fused with chemicals designed to stimulate the immune system.
No serious adverse events were associated with the vaccine, Schuster said.
The researchers commented that the approach might be useful in other forms of B cell cancer, such as chronic lymphocytic leukemia. Schilsky noted that, unlike other forms of cancer, the B cell cancers display a range of cell surface proteins that are distinctive.
"That's what makes this a feasible approach, because you can use that to develop a unique vaccine for each kind of lymphoma," he said.
The study was supported by Biovest International. The researchers reported financial links with Accentia Biopharmaceuticals, Biovest International, Antigenics, Biogen Idec, Genentech and Xeme Biopharma.