As the world fell victim to the coronavirus pandemic early this year, the field seemed wide open for the scores of pharmaceutical companies and universities that rushed to develop vaccines to curb Covid-19. But now that Pfizer Inc. and its partner BioNTech SE are rolling out a coronavirus shot, with rival Moderna Inc. not far behind, dozens of drugmakers further back in the development pack are suddenly facing a sobering possibility: The window to develop a successful vaccine before the field becomes crowded could be closing. That may leave some laggards unable to easily enroll enough volunteers in the trials needed to win regulatory authorization. In fact, drugmakers that are too many months behind might find themselves locked out of the vast U.S. market, which also is usually the most lucrative.
The problem is the stunning success of the early leaders’ inoculations. Pfizer and Moderna last month announced their vaccines achieved efficacy levels of around 95% in trial results, stoking optimism that the world will soon have potent weapons to stop a contagion that’s killed more than 1.5 million people. And, despite confusion surrounding its findings, AstraZeneca Plc appears to have another promising contender.