The MVA-MERS-S vaccine candidate has demonstrated safety and efficacy in a Phase Ib clinical trial, offering a promising step forward in combating the Middle East Respiratory Syndrome (MERS) coronavirus. The study, led by Prof. Marylyn Addo at the University Medical Center Hamburg-Eppendorf (UKE), investigated the vaccine's safety, immunogenicity, and optimal dosing regimen in healthy individuals, including those previously infected with SARS-CoV-2.
The MERS coronavirus, first identified in the Middle East in 2012, poses a significant global health threat, with a mortality rate of up to 36%. Transmitted from dromedaries to humans via droplet infection and capable of human-to-human transmission, the virus causes severe respiratory diseases. Currently, there is no specific treatment or effective vaccine available.
Trial Design and Results
The Phase Ib trial was a placebo-controlled, randomized, double-blind study involving 140 participants. Researchers evaluated two vaccine doses and two different vaccination intervals. The MVA-MERS-S vaccine, developed at the German Center for Infection Research (DZIF), is based on a modified vaccinia Ankara virus supplemented with protein components of the MERS virus.
The results, published in The Lancet Infectious Diseases, indicated that the vaccine is safe and effective, even in individuals with prior or concurrent SARS-CoV-2 infection. Participants reported only isolated local reactions, such as mild pain at the injection site, with no serious vaccine-related side effects observed.
Future Directions
"Further studies are now needed, including to verify these results in risk groups for severe MERS-CoV disease such as the elderly and people with relevant comorbidities," stated Prof. Addo, director of the Institute for Infection Research and Vaccine Development at the UKE and coordinator of the DZIF research area "Emerging Infections". These upcoming studies aim to solidify the vaccine's potential for broader use.
The development of the MVA-MERS-S vaccine is supported by the Coalition for Epidemic Preparedness Innovations (CEPI), a global partnership that includes the DZIF, focused on accelerating the development of vaccines and other countermeasures against epidemic and pandemic threats.
