Where do we stand with a possible vaccine?
In the past weeks, more in-depth characterization of the virus, our immune responses post infection, as well as preliminary Phase I trials suggest we are more likely to successfully develop a vaccine than 2 months ago. These vaccines are likely to lessen the severity of infections, as opposed to preventing COVID altogether. The market is expressing this optimism.
Whether this optimism is warranted depends on how efficacious and how safe these vaccines would be, as clinical data emerges in the next 6-9 months. The market will answer the efficacy question with Phase II data in the Fall, and the safety question with Phase III data late 2020/early 2021. Vaccines first and foremost need to be safe, as they are administered to healthy people, but note the safety question will be answered in the last stages of clinical trials when thousands of people have been tested.
When you hear that there are over 100 vaccines in development and 10 in clinical trials, you get the impression that one or more are bound to work. What we would note is that while there is a diversity in vaccine approaches (e.g. harmless viruses carrying genetic material of nCoV2, encapsulated DNA, RNA or viral antigens w/ adjuvants), the field is highly focused on one target – namely the spike protein, with good rationale. It is how tightly the spike protein binds to the ACE2 receptor on cells that makes the virus so infectious, so many are betting that as mutations occur as the virus multiplies and spreads, that the surviving strains will continue to feature the same spike protein, increasing the chances that our vaccines will work for the long haul. Developing vaccines using this one identifying piece of the virus is helping to speed up the progress, but we run the risk that the resultant vaccine could only be good enough, and may or may not adequately protect the most vulnerable populations.
Secondly, when we hear of availability of vaccines in the Fall, this refers to vaccines being manufactured at risk as we speak, before we have Phase II or Phase III data proving they are safe/efficacious. Vaccine availability does not equate to mass deployment and that consumers will get vaccinated. The likely path is if PII data is successful in the Fall, regulatory agencies around the world would consider approving vaccines for populations at highest risk of exposure (e.g. healthcare workers, essential workers, public-facing civil servants). It is unlikely, in our view, given that safety is paramount, that vaccines will be approved/made available for the general public until after we have successful PIII data in late 2020/early 2021.