COVID-19 vaccine development: What the next wave of vaccines in 2022 could look like
According to the WHO’s COVID-19 vaccine tracker, there are 137 vaccines currently in clinical development and another 194 in pre-clinical development.
As immunization rates increase, developers are now shifting their focus to vaccines that can be administered both as a primary series and booster shot or those that offer logistical advantages for distribution in countries that still face challenges with immunization campaigns. Meanwhile, creating vaccines that are effective against the Omicron poses a new challenge: with companies in the initial stages of testing against the variant.
Valneva
Valneva is eying up potential regulatory approvals for its COVID-19 vaccine in the first quarter of the new year.
The European Medicines Agency has started a rolling review of VLA2001, with the company set to supply up to 60 million doses to the bloc.
The shot uses Valneva’s Vero-cell platform, which is used for the company’s licensed Japanese encephalitis vaccine, IXIARO. VLA2001 consists of inactivated whole virus particles of SARS-CoV-2 with high S-protein density, in combination with two adjuvants, alum and CpG 1018.
If authorized, the company’s inactivated vaccine would complement the currently available mRNA and viral vector vaccines in the EU. In targeting the whole virus rather than solely the spike protein, the company hopes the vaccine will elicit a broad immune response. It is currently testing for cross-neutralization of VLA2001 against Omicron as well as the potential of the candidate as a booster shot.
Novavax
Having received the first authorization for its COVID-19 vaccine in Indonesia last month, Novavax this week received conditional marketing authorisation for its protein-based vaccine NVX-CoV2373 in the EU.
The company plans to submit a complete package to the US Food and Drug Administration by the end of the year, and is also in the process of seeking regulatory approval in several other markets: including the UK, Canada, Australia, United Arab Emirates and Singapore.
The two-dose vaccine, NVX-CoV2373, is engineered from the genetic sequence of the first strain of SARS-CoV-2: using Novavax's recombinant nanoparticle technology to generate antigen derived from the coronavirus spike (S) protein and is formulated with its saponin-based Matrix-M adjuvant.
Phase 3 trials have reported vaccine efficacy of 96.4% against the original virus strain, 86.3% against the Alpha (B.1.1.7) variant and 89.7% efficacy overall. Novavax is evaluating the vaccine against Omicron, as well as developing an Omicron-specific vaccine construct.
With storage temperatures of 2° to 8° Celsius, Novavax says the protein-based vaccine could potentially help increase access in hard-to-reach areas.
Sanofi and GSK
Sanofi and GSK hope to obtain Phase 3 trial results for their COVID-19 vaccine candidate in Q1, 2022.
They are also testing the recombinant adjuvanted vaccine as a booster shot, with initial results showing ‘consistently strong immune responses’ when delivered after an initial regimen of AstraZeneca, J&J, Pfizer or Moderna vaccines.
The Omicron variant was not circulating during the booster trial, but the companies are using sera from trial participants to establish the ability of the vaccine to cross-neutralize against Omicron.
Medicago and GSK
Medicago and GSK submitted the final part of their plant-based vaccine candidate's rolling review to Health Canada last week.
The vaccine reported an overall efficacy rate of 71% in Phase 3 trials earlier this month (the companies note that the figure should not be compared to authorized vaccines as different strains were in circulation during the trials).
The vaccine uses plants as a bioreactor to produce a protein particle that mimics the target virus, combined with GSK’s pandemic adjuvant. If it gets the green light from regulators, it will be the first ever plant-based vaccine authorized for human use.
Meanwhile, the regulatory filing process for the candidate has been initiated with the FDA (US) and MHRA (UK). Preliminary discussion is also underway with the WHO for preparation of the submission.
Curevac
Having ditched its first generation COVID-19 vaccine candidate in October, Germany’s Curevac is progressing with its second-generation vaccine program with GSK.
Curevac withdrew the first-generation CVnCoV from regulatory review in Europe given the promise of its second-generation candidate CV2CoV: which could have 10x higher immunogenicity.
CV2CoV features a new mRNA backbone, jointly developed with GSK. The optimized mRNA backbone targets improved intracellular mRNA translation for increased and extended protein expression.
In November, the company published preclinical data in the journal Nature, which compared CV2CoV with the Pfizer/BioNTech vaccine. Neutralizing antibody levels measured following full vaccination of animals with either 12µg of CV2CoV or a 30µg standard dose of the Pfizer/BioNTech were shown to be ‘highly comparable’.
University of Melbourne
Australia’s first mRNA drug product – an mRNA COVID-19 vaccine - is set to start clinical trials in the new year.
The Phase 1 clinical trials will be run by the Peter Doherty Institute for Infection and Immunity: a joint venture partnership between the University of Melbourne and the Royal Melbourne Hospital.
Funded by the Australian Government’s Medical Research Future Fund, results from the trial are expected in late 2022.
SK bioscience
South Korea’s SK bioscience is running Phase 3 trials for its protein subunit COVID-19 vaccine candidate, GBP510, following positive data from Phase 1/2 clinical trials released in November. Data from the phase 3 trial is expected in the first half of 2022.
The vaccine was developed with the University of Washington Antigen Design Research Institute and backed by CEPI under its ‘Wave 2’ funding round for next generation candidates.
The vaccine can be stored in normal refrigerated conditions of 2-8 degrees Celsius: allowing it to be distributed through the current vaccine logistics network.
Meanwhile, CEPI, the Coalition for Epidemic Prepardness Innovations, announced this week it is backing the company with up to $50m to develop a 'variant-proof' vaccine candidate against SARS-CoV, SARS-CoV-2 and other sarbecoviruses.
EnGeneIC
Australian biotech EnGeneIC, which is developing its nanocell tech for use in infectious diseases, is advancing a COVID-19 candidate in clinical trials.
The company’s EnGeneIC Dream Vectors (EDVs) are non-living nanocells originally developed for oncology applications. For the COVID-19 vaccine, EDVs are used the carry the COVID-19 spike protein. One of the points of difference of EDVs is that they could be used with vulnerable cancer patients or vulnerable populations for COVID-19 vaccination.
Early results indicate that the antibodies generated can neutralize COVID-19 and variants including Delta. EnGeneIC also believe the vaccine will be effective against mutants, as well as having the logistical advantages of one year of shelf-life and room temperature storage.
The vaccine entered Phase 1 trials in Melbourne in September. In November, the company announced a deal with US biotech ImmunityBio to develop, manufacture and commercialize the tech.
