Over the past week, investors optimistically pushed Vaxart’s (VXRT) share price up by over 100%. High short-interest and anticipation of positive Phase 1 results from the study of the company’s oral Covid-19 vaccine candidate VXA-CoV-1, appears to be a particularly potent combination. However, speculation on the results of clinical trials is a risky business, and investors were left disappointed when Vaxart’s were made public on Wednesday. Since the news broke, shares crated by ~60%. So, what happened? While the vaccine was well-tolerated and caused multiple immune responses against SARS-CoV-2 antigens, it failed to produce neutralizing antibodies in the study’s participants.