A single-shot Marburg vaccine shows promise
2023
Challenge
Marburg virus is a filovirus like the Ebola virus and causes similarly fatal disease. Fatality rates from Marburg can reach 90 percent and there are no approved vaccines or therapeutics. Moreover, Marburg outbreaks, while rare, do occur sporadically throughout sub-Saharan Africa, and the potential risk for an outbreak across all of Africa remains high due in part to the wide distribution of Egyptian fruit bats, which are known to harbor the virus and spread it to humans. The virus is also a potential biowarfare agent. Marburg has therefore been designated as a priority for urgent vaccine development.
Advance
IRP researchers developed a vaccine for the Marburg virus, called ChAd3-MARV (also known as cAd3-Marburg). In studies conducted by IRP scientists, the vaccine conferred rapid and lasting protection against lethal Marburg infection in non-human primates. In addition, when tested in a VRC-led, first-in-human, phase 1 clinical trial, the single-shot vaccine was found to be safe and elicited a rapid and lasting immune response in humans. The researchers observed a robust antibody response in 95 percent of participants four weeks after vaccination, which persisted in 70 percent of participants after nearly a year.
Impact
These results show that the IRP-developed Marburg vaccine is a promising tool that might provide long-lasting protection against the Marburg virus. As a single-shot vaccine, it is particularly suited for use when a rapid response to an outbreak is needed. The vaccine is advancing to clinical trials that will further assess its safety and ability to elicit an immune response in populations living in regions where the Marburg virus is common. These clinical trials will further assess the ability of the vaccine to protect against the virus, and if it is proven to be effective, will provide a lifesaving countermeasure against this highly fatal disease.
Publications
Hamer MJ, Houser KV, Hofstetter AR, Ortega-Villa AM, Lee C, Preston A, Augustine B, Andrews C, Yamshchikov GV, Hickman S, Schech S, Hutter JN, Scott PT, Waterman PE, Amare MF, Kioko V, Storme C, Modjarrad K, McCauley MD, Robb ML, Gaudinski MR, Gordon IJ, Holman LA, Widge AT, Strom L, Happe M, Cox JH, Vazquez S, Stanley DA, Murray T, Dulan CNM, Hunegnaw R, Narpala SR, Swanson PA 2nd, Basappa M, Thillainathan J, Padilla M, Flach B, O'Connell S, Trofymenko O, Morgan P, Coates EE, Gall JG, McDermott AB, Koup RA, Mascola JR, Ploquin A, Sullivan NJ, Ake JA, Ledgerwood JE; RV 507 Study Team. (2023). Safety, tolerability, and immunogenicity of the chimpanzee adenovirus type 3-vectored Marburg virus (cAd3-Marburg) vaccine in healthy adults in the USA: a first-in-human, phase 1, open-label, dose-escalation trial. Lancet. Jan; 401(10373):294-302. doi: 10.1016/S0140-6736(22)02400-X.
Hunegnaw R, Honko AN, Wang L, Carr D, Murray T, Shi W, Nguyen L, Storm N, Dulan CNM, Foulds KE, Agans KN, Cross RW, Geisbert JB, Cheng C, Ploquin A, Stanley DA, Geisbert TW, Nabel GJ, Sullivan NJ. (2022). A single-shot ChAd3-MARV vaccine confers rapid and durable protection against Marburg virus in nonhuman primates. Sci Transl Med. 14(675):eabq6364. doi: 10.1126/scitranslmed.abq6364.
This page was last updated on Friday, November 24, 2023