A new vaccine against tuberculosis
The results of the phase 2b controlled trial of M72/AS01E vaccine to prevent tuberculosis have been published in The New England Journal of Medicine by O. Van Der Meeren et al. The vaccine M72/AS01E provided 54.0% protection for Mycobacterium tuberculosis infected adults against active pulmonary tuberculosis disease, without evident safety concerns.
M72/AS01E consists of two proteins subunits PepA and PPE18 encoded by the genes Rv0125 and Rv1196. PE-PPE family of proteins is unique to mycobacteria and essential for infection, antigenic variation, and host-pathogen interactions. These 2 proteins, that have motifs Pro-Glu [PE] and Pro-Pro-Glu [PPE] respectively, are involved in the pathogenesis of TB disease and are able to elicit elicit both antibodies and T cells immune responses.
In this study the authors report the primary analysis, after a mean of 2.3 years of follow-up, of the randomized, double-blind, placebo-controlled, phase 2b trial of the M72/AS01E tuberculosis vaccine conducted in Kenya, South Africa, and Zambia .
These are their conclusions:
In conclusion, we found that the incidence of pulmonary tuberculosis was significantly lower with M72/AS01E than with placebo among healthy M. tuberculosis –infected, largely BCG-vaccinated, HIV-negative adults. 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