World TB Day: Twelve new tuberculosis vaccines in clinical testing phase

Leaders in the global fight against tuberculosis reported historic progress at a Wednesday Senate briefing on TB.

"A decade ago, we didn't have any preventive vaccines in clinical trials," Jennifer Woolley of the Aeras Global TB Vaccination Foundation, said. "Now, a total of 15 have entered the clinic, and a dozen are currently being tested."

Variable success rates within age groups and populations are one of the greatest issues within the development of TB vaccines. The current vaccine, Bacillus Calmette-Guérin, or BCG, was first developed in 1921 and has shown variable efficacy based on both geography and age group. Woolley said that BCG is really only effective in infants who have not already been exposed to TB, adding that "we need a vaccine that is going to protect against TB in multiple age groups and populations."

Clinical trials for the 12 new vaccines are currently in phase IIb, the proof-of-concept stage, and the first reports on their efficacy should arrive late this year or early next year. The most clinically advanced TB vaccine candidate in development is MVA85A, which is being developed through a partnership with Aeras and the Oxford-Emergent Tuberculosis Consortium, a joint venture between Emergent BioSolutions and the University of Oxford, where the vaccine was originally developed and investigated.

Woolley also said that there are many other second-generation vaccine candidates currently in the pipeline, but warned that progress should not be an indicator of success.

"We can't have a breakthrough and then be complacent," Woolley said. "That's how we got into the position where we're in today. We developed a new drug, and then nothing happened for 50 years. We developed a vaccine, and then we used it for over 90 years. As we have breakthroughs, we have to...keep building on those, to keep developing new and better and more effective technologies until we defeat this disease."