Last updated July 2012
Oxford-Emergent Tuberculosis Consortium/Aeras
MVA85A/AERAS-485—a recombinant attenuated version of the vaccinia virus (cowpox) combined with TB antigen 85A—is among the most clinically advanced TB vaccines. It was developed at Oxford University and is being evaluated as a booster of preexisting immune responses to antigen 85A, which are present in most people either as a result of BCG vaccination or natural exposure to TB. Phase I and II safety studies indicate that the vaccine has an acceptable safety profile; the most common side effects include local site of injection reactions and flu-like symptoms. Published immunogenicity results show induction of CD4 T-cell responses, which have generally been long-lasting and show a polyfunctional profile (meaning an ability to secrete multiple cytokines). Findings from studies in HIV-positive individuals are similar, but the CD4 T-cell responses have tended to be of lower magnitude and less durable. HIV status does not affect the safety of the vaccine, and—in collaboration with the Vaccine Research Center at NIH—the researchers have demonstrated that antigen 85A-specific CD4 T cells induced by the vaccine do not become preferentially infected by HIV.
Aeras has partnered with the Oxford-Emergent Tuberculosis Consortium Ltd. (OETC) on a phase IIb efficacy trial of this candidate in infants that completed enrollment in April 2011. A second phase IIb efficacy trial in HIV-positive adults, funded by the European and Developing Countries Clinical Trials Partnership (EDCTP), is now under way. The OETC, a joint venture between the University of Oxford and Emergent BioSolutions Inc., has the rights to fully commercialize the vaccine, and Aeras will have the rights to distribute the vaccine to resource-limited populations for humanitarian purposes.
- Scriba TJ, Tameris M, Smit E, et al. A phase IIa trial of the new tuberculosis vaccine, MVA85A, in HIV- and/or Mycobacterium tuberculosis-infected adults. Am J Respir Crit Care Med. 2012 Apr 1;185(7):769–78.
- Minassian AM, Rowland R, Beveridge NE, et al. A Phase I study evaluating the safety and immunogenicity of MVA85A, a candidate TB vaccine, in HIV-infected adults. BMJ Open. 2011 Nov 14;1(2):e000223.