Steady progress is made in the development of new
vaccines against tuberculosis (TB), researchers showed at a symposium in Spain. Several vaccine candidates are now being or soon will be tested in people.
European scientists gathered at the international
symposium "Research and development of new tuberculosis vaccines" in
Zaragoza, Spain, to share and discuss the progress in vaccines against the
airborne infectious disease. At the second and last day (4 June 2010),
Professor Stefan Kaufmann of the Max-Planck-Institute for Infection Biology in
Berlin, Germany, illustrated that TB infection is a vicious circle: Each day
about 125,000 infections result in roughly 25,000 TB cases, or 10 million new
cases of TB disease a year. Around
5,000 people die of tuberculosis every day. Drug resistant TB strains, and
HIV/TB co-infection further challenge global TB control.
Kaufmann emphasized that vaccines can play an important
role in turning the tide. He referred to studies showing that a 40-50 percent
reduction in TB could be achieved by new vaccines. Improved drugs could lead to
10-27 percent reduction and better diagnostics to a 13-42 percent drop.
He elaborated on the development of the VPM1002 vaccine
candidate by his team. VPM has successfully completed tests on safety and
immunogenicity in Germany. Further trials (phase Ib) are taking place in South
Africa at the moment.
Also in Spain progress is made. "It is a difficult
process from research to development," Professor Carlos Martin of the
University of Zaragoza said, describing the development of the MTBVAC01 vaccine
candidate discovered by him and his colleagues. After more than 10 years of
discovery and proof of concept and now 4 years of development, the vaccine is
taking its first steps out of the lab: The vaccine is scheduled to be tested in
people (phase I safety trials) the end of next year.
Dr.Jelle Thole, director of TuBerculosis Vaccine
Initiative (TBVI), in a meeting with Spanish journalists called MTBVAC01 a
leading vaccine in its kind. "It is the only candidate derived from the
actual bug that starts tuberculosis. All other vaccine candidates either are
based on improving or boosting BCG," he explained. TBVI, a European
research consortium for the development of new TB vaccines, aims to have 8
vaccines in phase II safety and efficacy trials in 10 years.
New vaccines are aimed to improve or replace BCG, the
only currently available vaccine against tuberculosis, which "does not
protect against the most prevalent form of the disease, and therefore has
little - if any - impact on the epidemiology of TB," Kaufmann said.
However, Martin stressed that BCG, developed in the
1920s, is "still in use because it is protective in children. In this
regard, new vaccines should be at least as good as BCG in protecting against
severe diseases as meningitis and miliar tuberculosis, and better in protecting
against respiratory forms of the disease."
Worldwide new tools against tuberculosis are in several
stages of development. Jan Gheuens, a senior program officer on the
tuberculosis team at the Bill & Melinda Gates Foundation, summarized at the
symposium: "Two vaccines are in large clinical trials, lots of vaccines
are in other phases. Furthermore, 8 drugs are in pre-clinical development or
further. And there is much excitement on the performance of a TB molecular
Gheuens briefly mentioned strategic challenges to be
considered. "What will be the next generation of new vaccines? New
antigens or a new approach to vaccines? What about the cost of progress, can we
raise the funds for larger clinical studies?" he questioned, adding that
fundraising is 'tough' and that not just greater awareness of the challenges in
TB, but also (public/political) commitment is needed.
The two day symposium (3-4 June 2010) was organized by
the University of Zaragoza, the foundation Ramon Areces and TuBerculosis
Vaccine Initiative (TBVI).
Contributed by: Bobby Ramakant