What happened

The COVID-19 vaccine space was on fire today. As of the market close Monday, shares of Inovio Pharmaceuticals (INO -3.81%) were up by 9.6%, while Moderna (MRNA -3.58%) rose 10.3%. Novavax (NVAX -4.32%), meanwhile, blasted higher by a jaw-dropping 24.7%, and VBI Vaccines (VBIV 1.50%) posted a comparable 24.2% gain.

Although none of these companies released an update on their COVID-19 vaccine program today, investors appear to be piling into the group as a whole ahead of the first batch of trial data slated to emerge within the next month or so. The first company to develop a viable COVID-19 vaccine should enjoy an enormous financial windfall after all.  

A woman being injected with a vaccine at a doctor's office.

Image Source: Getty Images.

So what

The world is slowly waking up to the painful realization that the current pandemic, along with the harsh social distancing measures required to contain it, may not end until a viable vaccine comes to market. Gilead Sciences' (GILD 3.62%) promising antiviral medication remdesivir could turn out to be a much-needed backstop to speed up recoveries and lower the mortality rate among severe cases. But it's not a preventative measure.

What's more, Gilead won't be able to manufacture enough of the drug to service the entire globe. As such, one or more vaccines will be needed to stamp out the COVID-19 pandemic. Inovio, Moderna, Novavax, and VBI Vaccines are all hoping to be among the first to fill this gigantic medical need with their experimental vaccine candidates.  

Now what

Where do things stand on vaccine development? Moderna became the first company to launch a human trial for a COVID-19 vaccine candidate earlier this year. This vaccine, called mRNA-1273, could be ready for widespread public consumption by mid-2021. Inovio, for its part, is developing a DNA-based vaccine dubbed INO-4800. This vaccine reportedly entered an early stage trial earlier this month. Novavax recently announced that its COVID-19 candidate, NVX-CoV2373, should enter clinical trials by mid-May. VBI Vaccines, on the other hand, is eyeing a pan-coronavirus vaccine targeting COVID-19, MERS, and SARS. The company's vaccine candidate is expected to enter human trials later this year. 

Are any of these stocks worth buying as a COVID-19 vaccine play? The short answer is no. We don't have a great track record when it comes to developing vaccines against coronavirus infections in humans. That doesn't mean this herculean effort is destined to fail, but it does make it impossible to handicap which company has the best chance of crossing the finish line. In other words, investors should probably take a cautious approach with this highly unpredictable field right now. All of these speculative biotech stocks could quickly reverse course and give up all of these recent gains.