Recent advances in the development of vaccines for tuberculosis.

Tuberculosis (Tb) continues to be a dreadful infection worldwide with nearly 1.5 million deaths in 2013. Furthermore multi/extensively drug-resistant Tb (MDR/XDR-Tb) worsens the condition. Recently approved anti-Tb drugs (bedaquiline and delamanid) have the potential to induce arrhythmia and are recommended in patients with MDR-Tb when other alternatives fail. The goal of elimination of Tb by 2050 will not be achieved without an effective new vaccine. The recent advancement in the development of Tb vaccines is the keen focus of this review. To date, Bacille Calmette Guerin (BCG) is the only licensed Tb vaccine in use, however its efficacy in pulmonary Tb is variable in adolescents and adults. There are nearly 15 vaccine candidates in various phases of clinical trials, includes five protein or adjuvant vaccines, four viral-vectored vaccines, three mycobacterial whole cell or extract vaccines, and one each of the recombinant live and the attenuated Mycobacterium tuberculosis (Mtb) vaccine.