From Gustav Ando, S&P Global Expert on Life Sciences:

Several of the most advanced projects are based on non-replicating adenoviral vector technology, and the COVID-19 market may mark a breakthrough for this type of vaccine – which is as yet unproven, though widely researched. Such vaccines may give rise to robust and effective immune responses, and are relatively safe, although there may be issues of pre-existing immunity to vectors based on human adenoviruses in individuals who have recently had adenoviral common colds.

Others are based on mRNA or plasmid DNA-based technologies, which are more experimental in nature, although generally acknowledged to be safe, easy to scale up, and with a strong research base indicating the potential for such vaccines to be effective. As with adenoviral vaccines, the COVID-19 pandemic may be proving ground for the DNA/RNA vaccine sector – which is backed by many years of research, but without approvals so far.

However, vaccines using more conventional approaches, such as inactivated (killed) whole virions or isolated recombinant proteins (subunit vaccines), are also in clinical-stage development, and it will be interesting to see whether tried-and-tested approaches pay off in the end.

The most sought-after goal in tackling the global COVID-19 virus pandemic will be the development of an effective vaccine that induces effective and long-lasting immunity against the COVID-19 virus.

Thirty COVID-19 vaccine candidates are currently in clinical trials (as of 27 August). To date, five vaccine candidates (from AstraZeneca [UK], Sinovac [China], Moderna [US], and two from Sinopharm [China]) have entered Phase III development, one is in Phase II/III (from a collaboration between BioNTech [Germany] and Pfizer [US]), four are in Phase II, and more are in Phase I/II and Phase I. One Phase I/II candidate (from the Gamaleya Institute, Russia) has received a temporary authorisation for public access on an initially limited basis in Russia, prior to entering Phase III development, although little evidence has been released on the efficacy of this candidate. More candidates are expected to enter Phase III during September.

In addition, selected promising preclinical-stage projects (some of which are very close to initiating clinical development) are in development. The success of any of these will depend on safety, level of neutralising immunogenicity, and strength and duration of protection, which are best measured in a large-scale randomised, double-blind, placebo-controlled Phase III trial, preferably in a country with a high background level of infections, in order to allow adequate differentiation of post-vaccination protection against real-world infections versus placebo.

A fully approved, effective treatment against COVID-19 will likely not be available until the first half of 2021.

For vaccines against COVID-19, our baseline assumption is that we will likely have a fully approved, effective vaccine with access to large populations across several countries in the summer of 2021. This has been the working assumption since the launch of our weekly tracker at the end of April 2020, and is based on assessment of typical development and regulatory timelines, the potential for clinical failures, the build-up of necessary manufacturing and distribution channels, and the global demand to fast-track a vaccine approval. The WHO has also recently reinforced this as a realistic timeline. We have clearly seen many significant clinical developments since April, but we have not seen data or updates that alters this assumption. Until mid-2021, we are likely to see – and have already seen – conditional/emergency approvals of experimental vaccines in subset populations. Importantly, these emergency approvals do not change any fundamental assumptions around the trajectory of the disease, or the ability of countries to reopen broader parts of their economies. We have seen some approvals in China and Russia, and pressure building in the United States for approvals before the end of 2020. These approvals are, however, limited in nature, based on vaccines with no evidence yet of protective effectiveness against real world infection

S&P Global is staying up-to-date on the topic. For more information, please visit https://ihsmarkit.com/research-analysis/life-sciences.html.

Learn more about the vaccine rollout in Latin America.