NCIt definition : A lyophilized formulation containing cultures of a low-virulent strain of Streptococcus
pyogenes, treated and killed with penicillin G, with potential sclerosing, immunostimulating
and antineoplastic activity. Besides from picibanil's direct damaging effect as a
sclerosing agent, it seems to have multiple effects on the immune system as a non-specific
immunostimulant. Picibanil activates the host immune system by stimulating the activity
of natural killer cells, macrophages and lymphocytes, and by enhancing the production
of several key immune mediators, including interleukins and tumor necrosis factor.;