PharmaShots Interview: Medicago's Nathalie Landry Shares Insight on Plant-Derived Vaccine for COVID-19

In an interview with PharmaShots, Nathalie Landry, Executive Vice President, Scientific and Medical Affairs at Medicago shared her views on positive results of P-I clinical trial results for its plant-derived COVID-19 vaccine.

Shots:

The results of the trial demonstrated that 100% of participants developed a promising antibody response after two doses of Medicago's COVID-19 adjuvanted vaccine candidate
The vaccine candidate was well-tolerated, common adverse events were generally mild and short in duration, and there were no severe adverse events reported
Medicago is partnering with GSK for its COVID-19 vaccine candidate and is open to new collaborations in the future. The company is currently focused on coronavirus and influenza and is developing a rotavirus-like particle vaccine candidate that is currently in P-I studies

Tuba: Can we have a detail on the Ph I results of Medicago's plant-derived vaccine in COVID-19 patients?

Nathalie: The results of the trial demonstrated that 100 percent of subjects developed a promising antibody response after two doses of Medicago's COVID-19 adjuvanted vaccine candidate.

Side effects were mainly mild to moderate and of short duration with no serious adverse events. Safety follow-up continues.
Phase 1 immunogenicity results demonstrate that adjuvants have the potential to improve humoral and cellular immune responses compared to the non-adjuvanted formulations.
All subjects in the group with GSK's pandemic adjuvant developed anti-spike IgG antibodies after a single dose of the vaccine either 3.75, 7.5, and 15 µg.
100 percent of participants who received an adjuvanted formulation developed neutralizing antibody responses after Dose 2 for all dose groups.
Anti-spike IgG and viral neutralization responses compared favorably to responses from COVID-19 positive patients outside of the study.
GSK's pandemic adjuvant was dose-sparing, with the lower 3.75 µg dose of CoVLP performing comparably with the 7.5 or the 15 µg doses.
Cellular Th1 immune responses of participants who received 3.75 or 7.5 µg doses were significantly higher in the adjuvanted formulations
CoVLP finished product is a liquid formulation that can be stored at 2°C to 8°C, easing cold chain management with existing vaccine infrastructure.

Tuba: Can we have a glance on the preclinical research results for this vaccine?

Nathalie: Preclinical data has not yet been published.

Tuba: Please share details on the origin and mechanism of the vaccine for our users?

Nathalie: Virus-like particles (VLPs) represent an exciting approach to vaccine development. VLPs mimic the native structure of viruses, allowing them to be easily recognized by the immune system. However, they lack core genetic material which makes them non-infectious and unable to replicate. In other words, they induce an immune response similar to a natural infection but without the inconveniences associated with it.

Medicago uses N. benthamiana plants, which is the most widely used experimental host in plant virology, due mainly to the large number of viruses that can successfully infect it. Its weakened immune system, the result of natural genetic changes over millennia, means genetic material can be successfully hosted by the plant and not rejected.

Medicago is applying its proprietary development process, explained below, to COVID-19.

Step1: Medicago researchers receive the antigenic viral gene sequence from global health organizations, synthesize it and introduce it into a plant-specific bacterial vector, that is then multiplied
Step 2: Plants are submerged in a solution containing the vector
Step 3: A vacuum is applied, forcing air out of the intracellular spaces. The vacuum is released and the difference in pressure forces the bacterial vector in the solution into the leaves (vacuum infiltration)
Step 4: The plants' cellular machinery acts like mini-factories for 4-6 days and produces VLPs

Step 5: Plants are harvested to extract VLPs the leaves are removed and blended into a solution, from which the vaccine material is isolated and extracted
Step 6: The VLPs are purified to obtain the final material needed for the vaccine.
Step 7: Relevant sterility & quality tests are conducted

Tuba: Are you planning to expand the potential of this plant-derived vaccine in other indications?

Nathalie: Medicago has already used its plant-derived vaccine technology in a number of applications and will continue to do so.

In 2009, the company produced a research-grade vaccine candidate against H1N1 in just 19 days.

In 2012, Medicago manufactured 10 million doses of a monovalent influenza vaccine candidate within one month for the Defense Advanced Research Projects Agency (DARPA), part of the U.S. Department of Defense.

In 2015, Medicago also demonstrated in principle that it could rapidly produce an anti-Ebola monoclonal antibody cocktail for the Biomedical Advanced Research and Development Authority (BARDA), part of the U.S. Department of Health and Human Services.

The company's first New Drug Submission for its seasonal recombinant quadrivalent VLP vaccine for active immunization against influenza in adults (18-64 years), is currently under review by Health Canada following the completion of a robust safety and efficacy clinical program in over 25,000 subjects.

Tuba: Does Medicago plan to assess vaccine as a standalone vaccine or always as an adjuvant to other vaccines?

Nathalie: Medicago has tested the vaccine as a stand-alone and with an adjuvant. An adjuvant can be of particular importance in a pandemic situation as it may boost the immune response and reduce the amount of antigen required per dose, allowing more vaccine doses to be produced and therefore allowing immunization of the greatest number of people.

Phase 2 and 3 will proceed with testing Medicago's adjuvanted vaccine candidate.

Tuba: Does Medicago plan to collaborate with other vaccines in development?

Nathalie: Medicago is partnering with GSK for its COVID-19 vaccine candidate and is open to new collaborations in the future.

Source: Nature

Tuba: Can we have an insight into Medicago's pipeline programs and their targeted indications?

Nathalie: Medicago is currently focused on coronavirus and influenza. Medicago is developing a rotavirus-like particle vaccine candidate that is currently in Phase 1 studies.

Tuba: When do you plan to initiate the Ph 2 study and can you share details of the trial such as combination options, patient numbers, trial design, dosing?

Nathalie: https://www.medicago.com/en/newsroom/medicago-and-gsk-announce-start-of-phase-2-3-clinical-trials-of-adjuvanted-covid-19-vaccine-candidate/

Tuba: Are you looking for a collaboration to develop and commercialize your therapies?

Nathalie: Medicago wants to be part of the scientific ecosystem, collaboration and partnerships are key in the pandemic situation but as far as the COVID-19 vaccine candidate is concerned, we only have a partnership with GSK.

Main Source Image: Phys

About Author:

Nathalie Landry is an Executive Vice President, Scientific and Medical Affairs at Medicago. She oversees a multidisciplinary team in charge of R&D, product development, analytical development, process development, pre/ clinical development, as well as PV, scientific and medical affairs