How do we produce the vaccine?
The vaccine is derived from tumor cells surgically removed from the patient. The cells are then grown in the laboratory to increase their number. Administering the vaccine depends on our ability to produce a sufficient number of cells.
On the day of vaccination the melanoma cells are irradiated, coated in a substance called DNP (dinitrophenyl) and mixed with BCG (weakened tuberculosis bacteria). DNP improves the cells’ immunological capability and BCG generates a local inflammatory response that is crucial to the immune process. The vaccine is injected subcutaneously into the arm or thigh every 21 days for a total of five doses. The first two vaccine doses are administered four days after intravenous administration of cyclophosphamide. Cyclophosphamide is a chemotherapeutic agent administered at a relatively low dosage for the purpose of eliminating T cells suppressing activation of the immune system (regulatory T cells).
What side effects does the vaccine cause? What is the toxicity profile?
This treatment method has a minimal amount of side effects. The vaccination may cause a fever, and a red node develops under the skin at the vaccination site. This node will disappear within the weeks/months after vaccination, leaving a small indented scar. Cyclophosphamide is associated with decreased appetite and nausea that are effectively managed by antiemetic medications.
What is the alternative to the vaccine?
The prospects for stage IV patients improved during the last years, and several new treatments, delivered also at Hadassah, are now available for this group of patients. However, no new treatment options for high risk and adjuvant patients arose since the approval, several decades ago, of the use of interferon-alpha for a period of one year. Furthermore, recent analysis of a large number of clinical trials has shown only modest efficacy, if at all, of this treatment. In this unsatisfying situation, melanoma vaccines represent an attractive alternative to interferon-alfa.