PT - JOURNAL ARTICLE AU - Morven E M Wilkie AU - Helen McShane TI - TB vaccine development: where are we and why is it so difficult? AID - 10.1136/thoraxjnl-2014-205202 DP - 2015 Mar 01 TA - Thorax PG - 299--301 VI - 70 IP - 3 4099 - http://thorax.bmj.com/content/70/3/299.short 4100 - http://thorax.bmj.com/content/70/3/299.full SO - Thorax2015 Mar 01; 70 AB - The development of an effective TB vaccine remains paramount to achieving the goal of global eradication of TB by 2050. The only licensed vaccine, BCG, has variable efficacy and is poorly effective in high burden countries. The development of promising candidate vaccines to either ‘boost’ a BCG primed immune system or replace BCG altogether is a key area for innovative research. Here, we discuss some of the issues encountered in the development of potential candidate vaccines and the future challenges.