As developers work to quickly generate a COVID-19 vaccine, the Wall Street Journal reports researchers are also trying to do so safely.
In particular, the Journal notes one concern they are addressing is disease enhancement, a scenario in which a vaccine makes the disease it is supposed to prevent worse. This problem stymied a recent effort to develop a dengue virus vaccine and a 1960s-era effort to develop an RSV vaccine. It also cropped up during an attempt to develop a SARS vaccine in the early 2000s, the Journal says.
It adds developers are designing their vaccines in ways they hope will avoid this effect. For instance, they are focusing on the spike protein and eliciting a neutralizing antibody response and not other responses that are thought to be linked to the disease enhancement, it says. It notes that developers like Moderna and Pfizer, among others, say their vaccines appear to be safe and well tolerated in early testing.
Phase III testing, the Journal notes, will be important for detecting this potential problem. "You won't know that is happening until you have somebody who got vaccinated and then was exposed," National Institutes of Health Director Francis Collins tells it.