An innovative new tuberculosis (TB) vaccine designed by a Spanish team and closely followed by the Bill & Melinda Gates Foundation is awaiting permission from health authorities to begin clinical trials with human patients.

"I hope the phase I trials will begin this year," said Carlos Martín, a professor of microbiology who led the team from Zaragoza University. The experimental drug is being made by the Galician biopharmaceutical firm Biofabri.

For the moment, the only existing vaccine against a disease that is on the rise (a third of the world's population is infected, and two million people die from it each year) dates from 1920, and has proven useless against Mycobacterium tuberculosis, the bacterium that causes TB. The new drug was 20 years in the making, said Martín, who started his research project from scratch.

"The approach is very new, and that is what Bill Gates liked about it," said the researcher, who met with Microsoft's founder in Spain this month to talk about the vaccine.

Gates' interest in the project dates back to January, when Martín gave a talk on the subject in Switzerland.

The origin of the MTBVAC project is an outbreak of resistant TB in Spain in 1993. Phase I trials should begin this year with 36 healthy individuals. This phase will cost just under a million euros, covered by Biofabri. After that, if trials go well, prices shoot up - which is where the Gates Foundation could play a crucial role.