CryoStim™ is a novel in-situ therapeutic cancer vaccine for patients with disseminated metastatic tumors. CryoStim™ combines AlloStim™ with cryosurgical ablation of a single tumor, stimulating a tumor-specific immune response which eliminates tumors wherever they are located through-out the body.

Patients are first infused with a dose of AlloStim™.  The rejection of the allogeneic mis-matched AlloStim™ cells results in the patient being immune to the drug. Immune patients then undergo a procedure to freeze an accessible tumor.  This causes the tumor to die by a process of necrosis, a pathological mechanism that results in an immune response to clean-up and repair the damaged tissue.  Additional AlloStim™ is injected into the necrotic tumor lesion resulting in a memory recall immune response to reject the allogeneic cells.  The combination of these two powerful immune responses results in the education of the immune system to perceive the dead tumor tissue as a danger.

Decades of immunotherapy trials of various types have shown that the immune system of cancer patients does not perceive the threat/danger of human cancer cells nearly as well as the rodent immune system does in experimental models of the same diseases.  This can explain why immunotherapy methods that work well in rodents do not transfer successfully into the clinic.

Tumors can be killed by necrosis through various ablation techniques, such as cryosurgery, radiofrequency ablation, laser interstitial therapy, high intensity focused ultrasound and focused microwave thermotherapy.  Only the cryoablation technique leaves tumor proteins such as heat shock proteins (HSP) and tumor antigens intact.  The other methods cause melting and fusing of the membranes and protein denaturalization.  Cryoablation has been successfully used and is accepted therapy for tumors in the prostate, liver, lung, kidney, breast and bone.  Cryoablation causes necrotic cell death secondary to direct cellular damage by ice crystals, and vascular and endothelial injury with eventual ischemia.

The presentation of tumor antigens in a highly inflammatory environment is a strategy to break the tolerance of the immune system to human tumors.