The investigators will be testing blood samples taken from the study patients to identify the precise antigens that the immune system is recognizing. With this information, they will tailor their vaccine for additional studies that monitor immune response more precisely.
Patients receiving the trial vaccine experienced relatively few side effects that included injection site pain and swelling, occasional muscle aches and mild fevers.
According to the investigators, most patients with CML will need to remain on Gleevec therapy for the rest of their lives. More than 90 percent of them will achieve remission, but about 10 to 15 percent of patients cannot tolerate the drug long term. "Often patients have low blood cell counts, fluid retention, significant nausea and other gastrointestinal problems," says B. Douglas Smith, M.D., associate professor of oncology at the Johns Hopkins Kimmel Cancer Center. Secondary therapies, including dasatinib and nilotinib, also have many side effects.
Another common side effect of Gleevec, says Smith, is fatigue. "Patients often tell me that they feel about 80 to 90 percent of what they should, and over time, this may have a big impact on their quality of life," he says.
Gleevec also cannot be taken during pregnancy, and since one-third of CML patients are in their 20s and 30s, many patients hoping to start families would like to discontinue taking it.
"Ultimately, should this vaccine approach prove to be successful, the ability to get patients off lifelong Gleevec therapy would be a significant advance," says Levitsky.
|Contact: Vanessa Wasta|
Johns Hopkins Medical Institutions