Vaccine Info

VTP-500 MERS Vaccine

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Last reviewed
December 23, 2023
Fact checked by
Robert Carlson, MD

VTP-500 MERS Vaccine Candidate

Barinthus Biotherapeutics plc VTP-500 (ChAdOx1) vaccine candidate prevents the Middle East Respiratory Syndrome Coronavirus (MERS) Coronaviruses (CoV). The ChAdOx1 MERS vaccine candidate contains the replication-deficient simian adenovirus vector ChAdOx1, containing the MERS Spike protein antigen. VTP-500 MERS vaccine utilizes the ChAdOx1 virus platform to encode MERS coronavirus spike protein to induce T cells and antibodies that block virus-host cell receptor binding and fusion or neutralize virus infection.

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 manufactured in well-established HEK293 cell lines containing the adenoviral E1 gene. Vaccitech licensed the needed patents from Oxford University to advance its programs. The ChAdOx1 vector patent was granted in the US and the EU, and the MVA-NP+M1 patent was granted in the EU and is pending in the US. 

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 MERS-CoV. VTP-500 has completed Phase I clinical trials in Britain and Saudi Arabia, and the University of Oxford is now extending the Phase Ib trial in the UK to assess vaccination of older adults.

On December 21, 2023, Barinthus Bio announced a project with the Coalition for Epidemic Preparedness Innovations (CEPI) and the University of Oxford, aiming to fast-track the development of a vaccine candidate known as VTP-500 to prevent MERS. The project will see CEPI, Barinthus Bio, and the University of Oxford take the MERS vaccine candidate from early development through Phase II clinical trials and, if the Phase II clinical trials are successful, develop an investigational ready reserve of 100,000 vaccines. The development partners are committed to enabling equitable access to VTP-500 in line with CEPI’s Equitable Access Policy. Due to VTP-500’s potential to significantly address MERS outbreaks, the European Medicines Agency (EMA) confirmed support for the program through the PRIME designation. 

Oxford, England-based Barinthus Biotherapeutics plc (Vaccitech) (NASDAQ: BRNS) is an immunotherapy and vaccine company. The Company’s proprietary platform comprises proprietary modified simian adenoviral vectors, known as ChAdOx1 and ChAdOx2, and the well-validated Modified Vaccinia Ankara, or MVA, boost vector, both with demonstrable tolerability profiles and without the ability to replicate in humans. 

VTP-500 MERS Vaccine Indication

VTP-500 (ChAdOx1) vaccine candidate is designed to protect people against MERS-CoV.

VTP-500 MERS Vaccine News

December 21, 2023 - “Coronaviruses are one of the most urgent infectious disease threats the world faces, so it’s vital that we get on with developing medical defenses against this particularly deadly one – MERS,” said Dr. Richard Hatchett, CEPI’s Chief Executive Officer. “With this project, we will both advance scientific understanding of the coronavirus family as a whole and, at the same time, bolster humanity’s ability to respond to an ever-present epidemic threat.”

September 18, 2023 - A vaccine to protect people against MERS was launched in September 2023. This is the third Phase I clinical trial of the ChAdOx1 MERS vaccine.

January 30, 2023 - The ECDC reported 2 613 cases of MERS-CoV, including 945 deaths, reported by health authorities worldwide since April 2012.

August 12, 2021 - Vaccitech plc provided an overview of the Company’s recent corporate developments. 

April 29, 2021 - Vaccitech plc announced the pricing of its initial public offering in the United States for total gross proceeds of $110.5 million.

March 22, 2021 - Vaccitech Ltd. announces Joseph Scheeren, PharmD, as an independent director to its Board of Directors.

August 21, 2020 - CEPI, Oxford University, and Janssen have entered into a collaboration worth up to $19M to progress the vaccine through Phase 2 studies and establish a human vaccine stockpile with the University. 

June 10, 2020 - RESEARCH ARTICLE: A single dose of ChAdOx1 MERS provides protective immunity in rhesus macaques.

April 17, 2020 - NIH press release: Investigational chimp adenovirus MERS-CoV vaccine protects monkeys. Vaccine neutralizes multiple MERS-CoV strains.

December 20, 2019 - Vaccitech’s partner, the University of Oxford’s Jenner Institute, in collaboration with The King Abdullah International Medical Research Centre (KAIMRC), announced that it had 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 trial will be the first Phase I clinical trial ever conducted in the KSA and will provide valuable clinical data. The trial is a collaboration between the Jenner Institute and the King Abdullah International Medical Research Center (KAIMRC), funded by the Department of Health and Social Care.

November 8, 2019 - Study: Humoral Immunogenicity and Efficacy of a Single Dose of ChAdOx1 MERS Vaccine Candidate in Dromedary Camels.The vaccination reduced virus shedding and nasal discharge (p = 0.0059 and p = 0.0274). The vaccine enhanced antibody responses in seropositive camels; these camels had a higher average age than seronegative. Older seronegative camels responded more strongly to vaccination than younger animals, and neutralizing antibodies were detected in nasal swabs.

VTP-500 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.

Findings: Between Dec 17, 2019, and June 1, 2020, 24 participants were enrolled (six to the low-dose, nine to the intermediate-dose, and nine to the high-dose group) and received a dose; 23 were available for follow-up at six months. The one dose of ChAdOx1 MERS vaccine was well tolerated with no serious adverse event reported during the six months of follow-up. Most adverse events were mild (67, 74%) and moderate (17, 19%). Six (7%) severe adverse events were reported by two participants in the intermediate-dose group (two feverish, two headache, one joint pain, and one muscle pain). Pain at the injection site was the most common local and overall adverse event, reported by 15 (63%) of the 24 participants. The most common systemic adverse event was headache, reported by 14 (58%), followed by muscle pain reported by 13 (54%). The vaccine-induced antibody and T cell immune responses in all volunteers; antibodies peaked at day 28, and T cell responses peaked at day 14 and continued until the end of follow-up at six months.

Clinical Trial NCT03399578: Suspended (The SARS-CoV-2 pandemic delayed recruitment but also provided an opportunity to apply findings from the rapid development of a ChAdOx1-vectored vaccine against SARS-CoV-2 to the further development of the MERS vaccine).

Findings: Between March 14 and Aug 15, 2018, 24 participants were enrolled: six were assigned to the low-dose group, nine to the intermediate-dose group, and nine to the high-dose group. All participants were available for follow-up at six months, but five (one in the low-dose group, one in the intermediate-dose group, and three in the high-dose group) were lost to follow-up at 12 months. A single dose of ChAdOx1 MERS was safe at doses up to 5 × 1010 viral particles with no vaccine-related serious adverse events reported by 12 months. One serious adverse event reported was deemed unrelated to ChAdOx1 MERS. 92 (74% [95% CI 66-81]) of 124 solicited adverse events were mild, 31 (25% [18-33]) were moderate, and all were self-limiting. Unsolicited adverse events in the 28 days following vaccination considered possibly, probably, or related to ChAdOx1 MERS were predominantly mild and resolved within the follow-up period of 12 months. The proportion of moderate and severe adverse events was significantly higher in the high-dose group than in the intermediate-dose group (relative risk 5·83 [95% CI 2·11-17·42], p<0·0001). Laboratory adverse events considered at least possibly related to the study intervention were self-limiting and predominantly mild in severity. A significant increase from baseline in T-cell (p<0·003) and IgG (p<0·0001) responses to the MERS-CoV spike antigen was observed at all doses. Neutralizing antibodies against live MERS-CoV was observed in four (44% [95% CI 19-73]) of nine participants in the high-dose group 28 days after vaccination, and 19 (79% [58-93]) of 24 participants had antibodies capable of neutralization in a pseudotyped virus neutralization assay.

Clinical Trials

No clinical trials found