The preliminary study the investigational vaccine involved 26 patients. Results were mixed. One patient has now been cancer free close to four years.
But results were not as good in the other 25 patients. For them, the disease progression was delayed only about two months.
Authors of the study funded by the National Cancer Institute say the early results give them encouragement. But they say a lot of work still needs to be done to prove whether this can be effective for more people.