A highly anticipated study of the first new tuberculosis vaccine in 90 years showed it offered no added benefit over the current vaccine in babies, a disappointing outcome, researchers said Monday.

The vaccine, known as MVA85A, is the most advanced of more than a dozen TB vaccines now in clinical trials in people, and scientists are poring over the results to learn why the trial failed and how the results can inform future studies.

"Obviously, we all would have liked to see greater protection," said Dr. Ann Ginsberg of Aeras, a non-profit biotech based in Rockville, Md.

The current TB vaccine, known as Bacille Calmette-Guérin, or BCG, was developed in 1921, and is given routinely to babies in countries with high rates of TB to prevent severe disease.

However, protection wears off in just a few years, and BCG does nothing to protect against the most common form of tuberculosis that invades the lungs of adults and adolescents, and can be transmitted through coughing and sneezing.

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