PharmaShots Interview: Medicago’s Brian Ward Shares Insights on the Data of Plant-Based COVID-19 Vaccine

In an interview with PharmaShots, Brian Ward, Medical Officer at Medicago shares his views on the P-III study of plant-based COVID-19 vaccine in combination with GSK’s pandemic adjuvant for the treatment of COVID-19

Shots:

The company reported efficacy and safety results from the P-III study of Medicago’s plant-based COVID-19 vaccine candidate + GSK’s pandemic adjuvant in ~24,000 adults aged ≥18yrs. across Canada, US, UK, Brazil, Argentina, and Mexico
The results showed the 71% overall vaccine efficacy rate against all variants of SARS-CoV-2, 75.3% against COVID-19 variant & 88.6% against the Gamma variant, vaccine candidate was well-tolerated, & no related serious adverse events were observed
Medicago has initiated the regulatory filing for the adjuvanted plant-based COVID-19 vaccine candidate with the US FDA and MHRA

Tuba: Discuss the key features of the Plant-Based COVID-19 Vaccine.

Brian Ward: Plant-based vaccines are categorized as recombinant protein-based vaccines. In the plant-based vaccine development process, living plants are used as bioreactors to produce a non-infectious virus-like particle (VLP) that mimics the target virus. Some of the key features of our plant-based vaccine technology ar

Rapid response: Once Medicago receives a virus strain, we’re able to produce a matching VLP in approximately two weeks.
Accurate: We have the ability to closely match the targeted strains with VLPs.
High-quality: Our process has stringent purification and quality controls that are built-in at every stage.

Tuba: How this plant-based COVID-19 vaccine candidate is different from currently commercialized COVID-19 vaccines?

Brian Ward: We cannot directly compare with other vaccines as we didn’t perform head-to-head comparison in the same clinical trial. However, we observed significant cross-protection against multiple variants of concern identified in the trial, especially Delta.

Tuba: Could you please discuss in brief about the P-II/III study design?

Brian Ward: The Phase 2/3 study has a multi-portion design to confirm that the chosen formulation and dosing regimen of the vaccine candidate (two doses of 3.75 µg of antigen combined with GSK’s pandemic adjuvant given 21 days apart) has an acceptable vaccine profile in healthy adults 18-64 years of age, elderly subjects aged 65 and over and adults with comorbidities.

The Phase 2 portion of the trial was a randomized, observer-blind, placebo-controlled study to evaluate the safety and immunogenicity of the adjuvanted recombinant COVID-19 plant-based vaccine candidate in subjects aged 18 and above.

The Phase 3 portion of the trial was an event-driven, randomized, observer-blinded, crossover placebo-controlled design that evaluated the efficacy and safety of the vaccine candidate formulation, compared to placebo, in over 24,000 subjects.

Tuba: What are the geographic locations where the trial is conducted?

Brian Ward: Phase 3 clinical trials were conducted in Canada, the US, the UK, Brazil, Argentina, and Mexico. A Phase 1/2 trial has also been initiated in Japan.

Tuba: Tell us about the data that Medicago has demonstrated from P-II/III study?

Brian Ward: We are extremely pleased with the results of our clinical trials, and if approved, we’re excited that this would be the world’s first plant-based vaccine for use in humans. Our results are highly relevant, as our trials demonstrated efficacy against the most globally dominant variants at the time. The results from our interim analysis show an overall efficacy of 75.3% against COVID-19 of any severity caused by the dominant Delta variant. Efficacy was 88.6% against the Gamma variant. No cases of the Alpha, Lambda, and Mu variants were observed in the vaccinated group while 12 cases were observed in the placebo group. Medicago’s COVID-19 vaccine candidate global efficacy against any variants was 71% as per protocol. The vaccine candidate was well-tolerated, with no related serious adverse events reported in the vaccine group.

Tuba: What are the different regulatory timelines for this Plant-Based COVID-19 Vaccine?

Brian Ward: We have submitted to Health Canada as part of our rolling submission and pending approval, we are planning to submit full data to the WHO, MHRA, and FDA in the upcoming months.

We are seeking a full license with the MHRA and anticipate seeking a license with EMA this year.

Tuba: Do you think that this vaccine will be effective on upcoming variants?

Brian Ward: With regard to future testing against emerging variants, including Omicron, we will be evaluating the immune response generated by our vaccine as soon as possible.

Source: European Vaccination Information Portal

About Author:

Brian Ward is the Medical Officer at Medicago & a professor of medicine and microbiology at McGill University. He also serves on numerous national and international advisory committees in the areas of vaccine use, vaccine safety, and international health. Dr. Ward received medical training at McGill, University of London, and Johns Hopkins (Tropical Medicine, Infectious Diseases, Microbiology)