BioSante reveals positive leukemia vaccine results, sending the stock soaring

USA-based BioSante Pharmaceuticals saw its shares leap 17% to $2.00 in early trading yesterday, after the company announced positive results of a human clinical study that show that its GVAX Leukemia vaccine may be able to reduce or eliminate the last remaining cancer cells in some chronic myeloid leukemia (CML) patients taking the cancer drug Gleevec (imatinib mesylate), which earned Swiss drug major Novartis $3.9 billion in sales last year (The Pharma Letter January 29).

All patients enrolled in the trial used Gleevec for at least one year and still had cancer cells present. The study was conducted by researchers at the Johns Hopkins Kimmel Cancer Center in Baltimore, Maryland, led by Hyam Levitsky, professor of oncology, medicine and urology at the Cancer Center. The research was funded by the National Institutes of Health, USA.

In a study published in Clinical Cancer Research, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center investigators used a vaccine made from CML cells irradiated to halt their cancerous potential and genetically altered to produce an immune system stimulator called GM-CSF. The treated cells also carry molecules, called antigens, specific to CML cells, which prime the immune system to recognize and kill circulating CML cells.