Therapeutic vaccines offer the prospect of treating cancer, and chronic infections such as HIV, but endogenous mechanisms that suppress immune responses and create immune tolerance are significant barriers to effective vaccination in these syndromes. Therapeutic vaccination requires nuanced approaches to break tolerance induced by developing malignancies and established infections that inhibit natural and vaccine induced immunity. Panel members are engaged in pre-clinical research to develop immunotherapies to interfere with tolerance mechanisms and the discussion will focus on therapies that target tolerance mechanisms to allow more effective immune responses to therapeutic vaccination.

• Describe the rationale for therapeutic vaccination to treat cancer and chronic infections
• Describe tolerance mechanisms that block effective immunity in patients with cancer and infections
• Discuss strategies to break tolerance, and the challenges to effective vaccination