Vaccine Info

ChAdOx1 MERS MERS-CoV Vaccine

ChAdOx1 Vaccine Description

ChAdOx1 MERS is a vaccine candidate to treat Middle East Respiratory Syndrome Coronavirus (MERS-CoV). The ChAdOx1 MERS vaccine consists of the replication-deficient simian adenovirus vector ChAdOx1, containing the MERS Spike protein antigen.

Vaccitech’s partner, the University of Oxford’s Jenner Institute, in collaboration with The King Abdullah International Medical Research Centre (KAIMRC), announced on December 20, 2019, that it has started a Phase I clinical trial in the Kingdom of Saudi Arabia (KSA) for a vaccine against the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Vaccitech retains commercial rights to this vaccine.

The patented Vaccitech adenovirus vectors are known as chimpanzee adenovirus Oxford 1 and 2 (ChAdOx1 and ChAdOx2), and are in the group E simian adenovirus family, similar to the widely-studied chimpanzee adenovirus 63. These viruses have been engineered to be replication-deficient and can be manufactured in well-established HEK293 cell lines containing the adenoviral E1 gene. Vaccitech has licensed the needed patents from Oxford University to advance all of the programs. Our ChAdOx1 vector patent is granted in the US and the EU, and our MVA-NP+M1 patent is granted in the EU and pending in the US.

ChAdOx1 Vaccine Indication

ChAdOx1 MERS is a vaccine candidate indicated to protect people against the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). 

Human coronaviruses were first identified in the mid-1960s. The best-known Conoaviruses are Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV) and the 2019 Novel Coronavirus (2019-nCoV).

MERS-CoV is a viral respiratory illness that is new to humans. It was first reported in Saudi Arabia in 2012 and has since spread to several other countries. Most people infected with MERS-CoV developed severe respiratory illness, including fever, cough, and shortness of breath. Only 2 patients in the U.S. have ever tested positive for MERS-CoV infection—both in May 2014.

The first-in-human trial is now being conducted in Oxford in UK healthy adult volunteers. The vaccine will be administered intramuscularly. This is an open-label, dose-escalation phase 1b trial to assess the safety and immunogenicity of the candidate ChAdOx1 MERS vaccine in healthy Middle Eastern adult volunteers aged 18-50. Volunteers will be recruited and vaccinated at the King Abdulaziz Medical City, M-NGHA, Riyadh. There will be 3 study groups and a total of 24 volunteers will be enrolled. Staggered enrolment will apply for the first three volunteers within each group. Volunteers will be first recruited into Group 1 and subsequently into Groups 2 and 3 following interim clinical safety reviews. Volunteers will be allocated to a study group by selecting eligible volunteers for enrolment in the order in which they were deemed eligible, following the screening.

The Estimated Primary Completion Date of this 1b study is September 1, 2020. The specific endpoints for safety and reactogenicity will be actively and passively collected data on adverse events. Change from baseline for safety laboratory measures will also be collected. The occurrence of serious adverse events will be collected during the whole study duration. 

ChAdOx1 Vaccine Dosage

ChAdOx1 MERS will be administered intramuscularly. Dosage levels and frequency are being tested in the clinical trials.

ChAdOx1 Vaccine Clinical Trials

Clinical Trial NCT04170829A Clinical Trial to Determine the Safety and Immunogenicity of Healthy Candidate MERS-CoV Vaccine. This research was funded by the Department of Health and Social Care (project number:16/107/01) as part of the UK Vaccine Network (UKVN), a UK Aid program to develop vaccines for diseases with epidemic potential in low and middle-income countries.

  • This is an open-label, dose-escalation phase 1b trial to assess the safety and immunogenicity of the candidate ChAdOx1 MERS vaccine in healthy Middle Eastern adult volunteers aged 18-50.
  • The first-in-human trial is now being conducted in Oxford in UK healthy adult volunteers. The vaccine will be administered intramuscularly.
  • Volunteers will be recruited and vaccinated at the King Abdulaziz Medical City, M-NGHA, Riyadh.
  • There will be 3 study groups and a total of 24 volunteers will be enrolled. Staggered enrolment will apply for the first three volunteers within each group.
  • Volunteers will be first recruited into Group 1 and subsequently into Groups 2 and 3 following interim clinical safety reviews.
  • Volunteers will be allocated to a study group by selecting eligible volunteers for enrolment in the order in which they were deemed eligible, following the screening.

Clinical Trial NCT03399578: Safety and Immunogenicity of a Candidate MERS-CoV Vaccine

  • All vaccinations will be administered intramuscularly. In Groups 1-3, each volunteer will receive one vaccination in total. In Groups 4 and 5, each volunteer will receive two vaccinations in total.
  • There are five different vaccine schedules:
    • Group 1 (n=6) will receive 5 x 10^9 vp ChAdOx1 MERS .
    • Group 2 (n=9) will receive 2.5 x 10^10 vp ChAdOx1 MERS.
    • Group 3 (n=9) will receive 5 x 10^10 vp ChAdOx1 MERS.
    • Group 4 (n=6-12) will receive 2.5 x 10^10 vp ChAdOx1 MERS at week 0 followed by a boost of 2.5 x 10^10 vp ChAdOx1 MERS at week 26.
    • Group 5 (n=6-12) will receive 2.5 x 10^10 vp ChAdOx1 MERS at week 0 followed by a boost of 2.5 x 10^10 vp ChAdOx1 MERS at week 4.
  • The study will assess the safety of the vaccines, and the immune responses to the vaccinations. Immune responses are measured by tests on blood samples.
  • Healthy adult volunteers will be recruited in Oxford, England.

Situation of MERS-CoV

At the end of September 2019, a total of 2,468 laboratory-confirmed cases of MERS, including 851 associated deaths (case–fatality rate: 34.4%) were reported globally; the majority of these cases were reported from Saudi Arabia (2,077 cases, including 773 related deaths with a case–fatality rate of 37.2%). “In one study 54.9% of primary cases were associated with direct camel exposure.” Ref: Reported Direct and Indirect Contact with Dromedary Camels among Laboratory-Confirmed MERS-CoV Cases. Conzade R et al. (Viruses. 2018 Aug 13;10(8). PMID: 30104551).

MERS-CoV poses a significant threat to public health security based on its epidemic potential and lack of currently available effective countermeasures and has been listed as a priority pathogen for research and development by the World Health Organization and other health agencies around the globe.

CONTENT SOURCES:  World Health Organization, US Centers of Disease Control and Prevention, clinicalTrials.gov, and the Precision Vaccinations news network.

Updated
January 19th, 2020