In an Interview with PharmaShots, Nathalie Landry, Executive Vice President, Scientific, and Medical Affairs at Medicago share her views on the P-II results of adjuvanted plant-based COVID-19 vaccine.
- The P-II study involves assessing the safety & immunogenicity of the CoVLP vs PBO in 306 subjects aged ≥18yrs. with two age groups (18-64yrs & over 65yrs.) across the US & Canada
- Results: All subjects who received an adjuvanted vaccine candidate developed significant antibody and cellular immune responses after two doses. Similar antibody responses were observed in adults and in the elderly with no AEs. The reactogenicity events were generally mild to moderate and short in duration.
- CoVLP has received the US FDA’s FTD while Health Canada has initiated a review of Medicago’s COVID-19 rolling submission under the interim order
Tuba: Discuss the P-II results of adjuvanted plant based COVID-19 vaccine candidate in detail.
Nathalie: Medicago is pleased to report positive interim Phase 2 clinical trial safety and immunogenicity data for Medicago’s plant-derived COVID-19 vaccine candidate, which has been tested in combination with GSK’s pandemic adjuvant. These results are part of the ongoing Phase 2/3 study and reiterate the promising profile observed during Phase 1 testing. Immunogenicity, as measured by the neutralizing antibody titer, was high – about 10 times higher than those in a panel of sera from patients recovering from COVID-19. No related severe adverse events were reported and reactogenicity was generally mild to moderate and short in duration.
The interim data from Phase 2 in adults and in the elderly have been published on an online preprint server at MedRxiv.
- This publication focuses on presenting safety and tolerability results, and immunogenicity, as measured by neutralizing antibody (NAb) and cell-mediated immunity (IFN-γ and IL-4 ELISpot) responses, in Adults aged 18-64 (Adults) and Older Adults aged 65+ (Older Adults).
- Medicago’s vaccine candidate with GSK’s pandemic adjuvant exhibited an acceptable safety profile and adverse events (AE) were primarily mild or moderate and of transient duration.
- AEs in Older Adults were more limited than those observed in the adult population.
- Medicago’s vaccine candidate with GSK’s pandemic adjuvant-induced a significant humoral immune response of similar strength in both age cohorts after two doses.
- The vaccine candidate induced a greater humoral response in Adults than Older Adults after a single dose but after the second dose, both age cohorts responded with NAb titers that were about 10 times higher than those in a panel of sera from patients recovering from COVID-19.
Tuba: Unveils the design of P-II/III study evaluating plant-based vaccine.
Nathalie: The Phase 2/3 study is a multi-portion design to confirm that the chosen formulation and dosing regimen of CoVLP (two doses of 3.75 µg CoVLP combined with GSK’s pandemic adjuvant given 21 days apart) has acceptable immunogenicity and safety 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-derived vaccine candidate in subjects aged 18 and above. It was conducted in multiples sites in Canada and the United States in a population composed of healthy adults (18-64y), elderly adults (over 65y), and adults with comorbidities. Each age group enrolled up to 306 subjects randomized 5:1 to receive the adjuvanted CoVLP vaccine candidate: placebo and with 2:1 stratification in older adults (65-74 and ≥75). All subjects will be followed for a period of 12 months after the last vaccination for the assessment of safety and durability of the immune responses to the vaccine candidate, which will be the final analysis.
The Phase 3 portion is an event-driven, randomized, observer-blinded, crossover placebo-controlled design that will evaluate the efficacy and safety of the CoVLP formulation, compared to placebo, in up to 30,000 subjects in North America, Latin America, and Europe and within the same populations.
Tuba: Highlight the contributions of GSK in this collaboration for adjuvanted plant based COVID-19 vaccine?
Nathalie: The use of an adjuvant is of particular importance in a pandemic situation, as it can reduce the amount of antigen required per dose, allowing more vaccine doses to be produced and made available to more people. GSK’s pandemic adjuvant is an oil-in-water emulsion combining several ingredients that have been carefully selected to stimulate the immune system, it has been used successfully in pandemic flu vaccines in the past.
Tuba: Can we have a discussion on the efficacy rate & safety of this plant-based vaccine of Covid-19?
Nathalie: Medicago is currently testing the vaccine for safety and efficacy in its Phase 3 trials.
Tuba: Continuous efforts are still ongoing to produce an efficient vaccine for COVID 19, owing to its great potentials, in this scenario how can plant-based vaccine leave its mark on the world?
Nathalie: Medicago uses a unique plant-based platform to produce its therapeutics. Potential benefits of Medicago’s plant-based technology include:
- Rapid – Ability to deliver research-grade vaccines doses in 19 days and clinical-grade in 6-8 weeks.
- Accurate – Designed to accurately match the recommended target strains.
- Versatile – Ability to produce both vaccines and antibodies with the same platform.
- Scalable – Ease of scale-up, one plant or 10,000 plants require the same growth conditions.
Tuba: Do you think will it give tough competition to the other vaccines in the market?
Nathalie: The data so far gives us confidence as we continue to move forward with our Phase 3 of clinical trials.
Tuba: Highlight the key features of novel plant based COVID vaccine? Are conventional methods have been applied for developing the vaccine?
Nathalie: The company uses proprietary plant-based technology to develop protein-based therapeutics. Unlike traditional vaccination development, Medicago does not use animal products or live viruses to create its products. Instead, it uses Virus-Like Particles (VLPs) that mimic the shape and dimensions of a virus, which allows the body to recognize them and create an immune response in a non-infectious way.
Tuba: How it will be a revolutionary treatment for patients as this will be the world’s first plant-based vaccine?
Nathalie: Plants are highly efficient at producing proteins of varying complexity, serving as bioreactors – or mini-factories – for our vaccines and protein-based therapeutics. Medicago’s plant-based production platform demonstrates agility, accuracy, and speed by limiting the risk of undesirable mutations (no use of live viruses) and contamination during production, and significantly shortening production timelines.
Tuba: When can we expect the availability of this vaccine?
Nathalie: Medicago is working hard with the objective to submit a COVID-19 vaccine to health authorities for regulatory reviews as soon as possible. We expect to complete Phase 2/3 clinical trials by summer 2021. Regulatory submission to Health Canada and the FDA would follow successful clinical trials. Health authorities are moving as quickly and safely as possible to review and approve successful vaccines.
Tuba: What would be the targeted geographies for seeking approval of CoVLP?
Nathalie: We have an agreement with the Canadian government to supply up to 76M doses of our COVID-19 vaccine upon regulatory approval.
Image Source: Nature
About Nathalie Landry:
Nathalie Landry is the Executive Vice President, Scientific and Medical Affairs at Medicago. She joined Medicago in 2000 as Director of Strategic Development and later became Senior Director of Product Development.