The Tuberculosis Vaccine Development Pipeline: Present and Future Priorities and Challenges for Research and Innovation

This chapter describes present and future priorities and challenges towards tuberculosis (TB) control by novel vaccination strategies. The complex continuum of Mycobacterium tuberculosis (Mtb) infection and TB disease makes research and innovation (RI permanent non-conversion, in which infection apparently does not establish itself despite frequent exposure to Mtb; latent TB infection (LTBI) during which active disease is prevented by active containment of Mtb; progression from LTBI to active TB disease through reactivation; and elimination of Mtb in later stages of LTBI. Deeper insights into the different stages of infection and disease in humans can provide information for vaccine RI prevention of disease; prevention of recurrence; and sterile eradication of Mtb. Recent experiments with non-human primates and clinical trials have provided encouraging evidence that at least some of these outcomes can be accomplished, and the future will tell which types of vaccines and immunization schedules will be required for efficacious TB control.