A new vaccine candidate shows promise for preventing active pulmonary tuberculosis (TB) in adults infected with Mycobacterium tuberculosis. The vaccine, M72/AS01E, provided 54% protection against active pulmonary TB.
In a randomized, double-blind, placebo-controlled study, HIV-negative adults ages 18 to 50 with latent M tuberculosis were randomly assigned to receive 2 doses of the M72/AS01E vaccine or placebo a month apart. Researchers evaluated the safety and efficacy of the vaccine against progression to bacteriologically confirmed active pulmonary TB.
Of the 1623 participants who received 2 doses of the vaccine, 10 went on to develop tuberculosis, reflecting an incidence of 0.3 cases per 100 person-years. Of the 1660 participants who received placebo, 22 went on to develop tuberculosis, reflecting an incidence of 0.6 cases per 100 person-years.
Unsolicited reports of adverse events were more common in the group that received the vaccine (67.4% to 45.4%), with investigators attributing the disparity to injection-site reactions and flu-like symptoms.
“The possibility of developing an effective vaccine for TB has profound implications from a public health perspective,” noted William Knaupp, MD, a pulmonologist at Mount Sinai Doctors of Long Island, who was not involved in the research. “It would seem that targeting adolescents and young adults would be desirable not only because of the apparent greater efficacy in this population but also because of the potential for a greater overall health benefit if the vaccine proves to have long-term protective effects.”
The study researchers are optimistic about the vaccine’s long-term prospects. “These promising results provide an opportunity to better understand the mechanisms by which this vaccine may confer protection against tuberculosis and support its further evaluation.”
Van Der Meeren O, Hatherill M, Nduba V, et al. Phase 2b controlled trial of M72/AS01E vaccine to prevent tuberculosis. N Engl J Med. 2018;379:1621-1634.