* Vaccine was given to 19 CML patients
* Shares up as much as 22 pct (Adds details, updates share movement)
March 11 (Reuters) - BioSante Pharmaceuticals Inc BPAX.O said a small study showed its GVAX leukemia vaccine may be able to reduce or eliminate the remaining cancer cells in some chronic myeloid leukemia (CML) patients taking cancer drug Gleevec, sending its shares up 22 percent.
The company said the GVAX leukemia vaccine was given to 19 CML patients with measurable cancer cells, despite taking Gleevec for at least one year.
After a median of 72 months of follow-up, the number of remaining cancer cells declined in 13 patients, eight of whom had increasing disease burden before vaccination.
Twelve patients reached their lowest levels of residual cancer cells to date following vaccination. In seven patients, CML became completely undetectable, the company said.
Patients receiving the vaccine experience relatively few side effects.
The study, funded by the National Institutes of Health, was conducted by researchers at the Johns Hopkins Kimmel Cancer Center.
Using cancer vaccines may be a good way to “mop up” residual disease but more research is needed to confirm and expand the results, lead investigator Hyam Levitsky said in a statement.
Most patients with CML will need to remain on Novartis’ NOVN.VX Gleevec therapy for the rest of their lives. More than 90 percent of them will achieve remission, but about 10 percent to 15 percent of patients cannot tolerate the drug long term, the company said.
Shares of BioSante were up 11 percent at $1.90 in morning trade on Nasdaq. They touched a high of $2.08 earlier in the session. (Reporting by Jennifer Robin Raj in Bangalore; Editing by Aradhana Aravindan, Ratul Ray Chaudhuri)