What happened

Shares of the clinical-stage biotech Vaxart (VXRT -3.67%) slid by as much as 11.3% in early-morning action Wednesday. The developmental vaccine company's shares appear to be reacting negatively to the news that Johnson & Johnson (JNJ -1.82%) has advanced its single-shot COVID-19 vaccine candidate, known as Ad26.COV2.S (JNJ-78436735), into a pivotal-stage trial.

Although the study's full results won't be ready until March 2023, J&J's chief scientific officer, Paul Stoffels, said in a press conference that the vaccine's safety and efficacy profile could become known quantities by year's end. That's potentially bad news for other COVID-19 vaccine developers like Vaxart who are only now entering early-stage trials.  

A gloved hand holds a vial of blood labeled Coronavirus

Image Source: Getty Images.

Vaxart's shares have bounced back to a degree since hitting their intraday low, but they are still down by 8.23% as of 10:23 a.m. EDT Wednesday.

So what

Vaxart is reportedly gearing up to begin patient enrollment for a phase 1 trial of its oral COVID-19 vaccine this month. While the start of human trials is an important milestone, the fact is that Vaxart appears to be at least a year behind the leaders in the space, such as J&J.

On a positive note, Vaxart's oral vaccine could sport several key advantages over the injected products, which may help it carve out a profitable niche. That said, the first wave of COVID-19 vaccines are surely going to gobble up the lion's share of the market. 

Now what

Is this dip a buying opportunity? Vaxart's shares should rebound nicely if the company reports positive phase 1 results for its COVID-19 vaccine candidate later this year. That said, this is a risky developmental-stage biotech stock that is arguably suited only for aggressive investors.