MERS Coronavirus Vaccine Trial Being Conducted in Humans

The MVA-MERS-S vaccine is based on an attenuated virus, modified vaccinia virus Ankara, which had previously been used in a smallpox eradication vaccination campaign.

A first-in-human trial with a vaccine against Middle East respiratory syndrome (MERS) has been conducted by scientists at the University Medical Center Hamburg-Eppendorf (UKE) and the German Center for Infection Research (DZIF). The MVA-MERS-S vaccine was well-tolerated and triggered the development of antibodies and T cell immunity, according to the study authors.

“The results of this vaccine trial are also important and promising with regard to the development of a vaccine against (severe acute respiratory syndrome coronavirus 2) SARS-CoV-2, the new coronavirus,” said Marylyn Addo, head of the Division of Infectious Diseases at the UKE and scientist at the DZIF, in a press release. “The development of the MERS vaccine provides a basis upon which we at the DZIF can rapidly develop a vaccine against the new coronavirus.”

The MVA-MERS-S vaccine is based on an attenuated virus, modified vaccinia virus Ankara, which had previously been used in a smallpox eradication vaccination campaign. It has been alternated to contain protein components from the MERS coronavirus. The recombinant vaccine is intended to boost immunity against MERS coronaviruses and now serves as the basis for developing a vaccine against SARS-CoV-2, according to the study authors.

A total of 23 healthy volunteers took part in the trial, with each volunteer vaccinated twice with MVA-MERS-S at an interval of 4 weeks between vaccinations. The trial was intended to find whether the experimental MVA-MERS-S vaccine was well-tolerated and safe in humans and whether the vaccine triggers humoral and cellular immune responses in humans.

The findings showed that the vaccine was well-tolerated, with local adverse effects, such as mild erythema, occurring most frequently in 69% of the trial subjects.

“After the second injection of MVA-MERS-S, antibody formation and T cell responses occurred in 87 percent of the trial subjects,” said co-author Christine Dahlke, MD, in a press release.

According to the study authors, a phase 1b trial will be conducted in which the vaccine will be tested in 160 subjects in Hamburg and Rotterdam. The results and tests from this trial are intended to be used for the development of a vaccine against the coronavirus disease 2019. The same viral vector, MVA, will be used in the upcoming trial, in which they will insert a SARS-CoV-2 spike protein to replace the MERS-CoV spike protein, according to the press release.

REFERENCE

Promising MERS coronavirus vaccine trial on humans — useful insights for vaccine development against SARS-CoV-2. DZIF. https://www.dzif.de/en/promising-mers-coronavirus-vaccine-trial-humans-useful-insights-vaccine-development-against-sars. Published April 21, 2020. Accessed April 28, 2020.