TORONTO -- Biopharmaceutical company Medicago and drug maker GlaxoSmithKline reported Tuesday positive efficacy and safety results from the Phase 3 trial of their plant-based COVID-19 vaccine.
Medicago, which is headquartered in Quebec, reported in a news release that their Phase 3 placebo-controlled study -- conducted in more than 24,000 subjects in six countries who are 18 and older -- reported an overall vaccine efficacy rate of 71 per cent against all variants of SARS-CoV-2 which were circulating at the time of the study.
鈥淰accine efficacy was demonstrated in an environment dominated by SARS-CoV-2 variants unlike most published Phase 3 efficacy trials for currently licensed COVID-19 vaccines that were conducted when only the ancestral virus was circulating,鈥 the release states.
In an interview with 麻豆影视, Executive Vice-President of Innovation Development and Medical Affairs for Medicago, Marc-Andre D鈥橝oust, said the study ended up being focused entirely on COVID-19 variants.
鈥淚n our efficacy analysis, we have not seen any cases of the original strain of COVID-19鈥o the results show the vaccine is efficacious against all of those variants we have observed during the study,鈥 he said.
The vaccine uses plant-based technology to create 鈥渧irus-like particles,鈥 (VLP) which are designed to mimic the structure of viruses so that the immune system can recognize them and build an antibody response to them. VLP do not contain core genetic materials, which makes them non-infectious and unable to replicate.
D鈥橝oust said it only takes Medicago 鈥渄ays鈥 to produce the vaccine from the moment they have the virus sequence in researchers鈥 hands.
鈥淪o for a new virus, for example, once we have the sequence, in 19 days, we've found that we can produce a research-grade VLP which is the structure of the vaccine that we're using鈥rom there, we can continue with the development and that's what we did for the COVID-19 vaccine development early in 2020,鈥 he explained.
Medicago鈥檚 vaccine demonstrated 75.3 per cent efficacy against COVID-19 of any severity for the Delta variant, which D鈥橝oust said is the most widely circulated strain, and 88.6 per cent efficacy against the Gamma variant.
A small number of severe cases of COVID-19 were observed in the study, but none occurred in the vaccinated group, Medicago said in the release.
鈥淭hese results are great, these results show the vaccine is efficacious,鈥滵鈥橝oust said. 鈥淲e鈥檝e developed [our] technology for 20 years now, and over the last two years we鈥檝e developed a COVID-19 vaccine and these results show that the plant-based platform that we have used to produce the vaccine can produce an efficacious vaccine.鈥
No cases of the Alpha, Lambda, or Mu variants were observed in the vaccinated group while 12 cases were observed in the placebo group, the release states.
The Omicron variant was not circulating during the study, but D鈥橝oust said in the interview that Medicago is already analyzing the new strain.
鈥淲e're currently evaluating the cross reactivity of the antibodies raised by our current vaccine against Omicron,鈥 he said, adding that the company has 鈥渢aken action鈥 in case a change is needed in their vaccine in light of the variant.
The Phase 3 study reported no serious adverse events and reactions were 鈥済enerally mild to moderate and transient,鈥 with symptoms lasting on average from one to three days.
The full results of the Phase 3 study will be released in a peer-reviewed publication, and Medicago will 鈥渋mminently鈥 seek Health Canada approval based on the Phase 3 results as part of its rolling submission.
鈥淚f approved by authorities, this vaccine will be the first plant-based vaccine to be used in humans,鈥 D鈥橝oust said. 鈥淲e鈥檙e very proud鈥because] it will also be the first vaccine to be developed in Canada.鈥
Professor of Virology and Immunology at Memorial University Nfld., and Vice President of the Canadian Society for Virology Rod Russell told 麻豆影视 in an interview Monday that he was not surprised at news of Medicago鈥檚 positive results.
鈥淚t鈥檚 really good that this is an alternative鈥 like the idea that it鈥檚 a different type of platform [plant-based] which is good for hesitancy,鈥 Russell said. 鈥淲e鈥檙e going to need different vaccines or a range of vaccines鈥o my reaction to the trial data is encouraging.鈥
Russell noted that Canada 鈥渆xperienced a delay鈥 in access to vaccines at the beginning of the pandemic partly because none were being made domestically.
鈥淪o the fact that we鈥檒l have vaccines made in Canada that鈥檚 a good thing鈥t cuts down on supply chain issues鈥 he said of Medicago. 鈥淚f we start seeing variant specific vaccines at some point again鈥.we could switch right away and start making the new sequence, as fast as other companies do.鈥
鈥淪o this is good news for sure,鈥 Russell said.
