Don't blink: The dynamics in the coronavirus vaccine race are shifting so quickly, you just might miss something. Potential fortunes are riding on what happens.

There are 48 COVID-19 vaccines currently in clinical testing, according to the World Health Organization. Not all of them are potential candidates to reach the U.S. market, though. Several of the experimental vaccines are being developed by companies whose shares aren't publicly traded.

There are plenty of coronavirus vaccine maker stocks for investors to watch. Here's an update on where things stand now for the leading COVID vaccine stocks.

Vaccine bottle with a dollar sign in it next to a syringe and a bottle labeled "SARS-CoV-2 vaccine" on its side

Image source: Getty Images.

Authorization decisions ahead

There are two clear leaders in the coronavirus vaccine race. Both await emergency use authorization (EUA) decisions by the U.S. Food and Drug Administration (FDA). 

Pfizer's (PFE -0.19%) and BioNTech's (BNTX -0.45%) BNT162b2 is actually already being shipped though EUA is still pending. Doses of the vaccine are being flown in from Pfizer's manufacturing facility in Belgium to Chicago and from there on to distribution hubs across the U.S. The plan is to have vaccine doses ready to be delivered to administration sites as quickly as possible once the FDA makes its decision.

That decision is just around the corner. The FDA is convening an advisory committee meeting on Dec. 10 to review the EUA filing for BNT162b2. The agency should announce whether or not Pfizer's vaccine will receive EUA shortly afterward.

Moderna (MRNA 0.89%) won't be far behind. The biotech filed for EUA of mRNA-1273 on Nov. 30 after reporting earlier in the day that the experimental vaccine was 100% effective at preventing severe cases of COVID-19. An FDA advisory committee is scheduled to meet to review Moderna's EUA filing on Dec. 17.

Based on efficacy and safety data announced so far, the chances of getting a thumbs-up appear good for both vaccines.

The second wave

Three other COVID-19 vaccines could potentially be headed for EUA in the first half of 2021. AstraZeneca (AZN 0.49%) is the only company in this group to announce interim efficacy results from a late-stage study thus far. The big drugmaker reported an average interim efficacy of 70% for AZD1222. The details behind AstraZeneca's interim results were intriguing.

AstraZeneca gave some participants in its late-stage study a half dose of AZD1222 followed by a full dose at least one month later. This group achieved efficacy of 90%. However, this group was much smaller than the group given a full dose of AZD1222 followed by a full-dose boost at least one month later. This larger group had a much lower efficacy of 62%.

While AstraZeneca is preparing to file for early approval in some countries based on these results, it probably won't be able to submit for EUA just yet. Why? The results announced weren't from the company's U.S. late-stage study of AZD1222. Also, AstraZeneca didn't initially include a combined half- and full-dose regimen in its U.S. study, but plans to do so now. 

Johnson & Johnson (JNJ -0.69%) is currently conducting two global late-stage clinical trials of its COVID-19 vaccine candidate JNJ-78436735 -- one with a single-dose regimen and another with a two-dose regimen. Like AstraZeneca's AZD1222, J&J's vaccine uses a nonreplicating adenovirus to insert DNA into cells. This DNA contains instructions for producing a protein that's identical to the spike protein on the surface of the novel coronavirus that causes COVID-19.

It's too soon to know how effective J&J's experimental vaccine will be. The healthcare giant hasn't provided a specific date for when interim efficacy results will be available, but sometime in early 2021 seems likely.

Novavax (NVAX -0.95%) is another company with a late-stage COVID-19 vaccine candidate that investors will want to watch. The biotech expects to announce interim results from a U.K. late-stage study of its vaccine, NVX-CoV2373, early next year. Novavax had hoped to begin a U.S. late-stage study by the end of November, but recently reported a delay related to resolving manufacturing issues with the FDA. The company now anticipates initiating a late-stage study of NVX-CoV2373 in the U.S. and in Mexico within the next few weeks. 

Next stage, late stage 

Three COVID-19 vaccine candidates are currently in phase 2 testing. Two are being developed by Chinese drugmakers and aren't likely to factor into the U.S. or major European markets. CureVac (CVAC -3.46%), however, has already lined up an agreement with the European Union to supply at least 225 million doses of its COVID-19 vaccine CVnCoV.

Like Pfizer's and BioNTech's BNT162b2 and Moderna's mRNA1273, CVnCoV uses messenger RNA (mRNA) to direct cells to produce proteins identical to the spike protein found on the surface of SARS-CoV-2. CureVac plans to begin a pivotal phase 2b/3 study of CVnCoV soon, pending regulatory approval. If all goes according to schedule, an interim analysis could be conducted in the first quarter of 2021. 

Multiple winners likely

Even though Pfizer/BioNTech and Moderna are the leaders right now, don't look for there to be a winner-takes-all scenario with COVID-19 vaccines. Multiple winners are quite likely.

Of the big pharma stocks, Pfizer seems likely to be the biggest winner, at least initially. AstraZeneca and Johnson & Johnson have pledged to make their coronavirus vaccines available at cost during the pandemic; Pfizer hasn't. However, J&J could have a competitive advantage with its single-dose vaccine if it proves to be safe and has a high efficacy.

Turning to the relatively small biotech stocks, Novavax appears to have the most upside. It's the smallest of the leading COVID vaccine makers by far, with a market cap of less than $10 billion. However, Novavax still hasn't reported interim efficacy results. If NVX-CoV2373 doesn't deliver efficacy in the ballpark of 90% or greater, Novavax could fall by the wayside.

The next few weeks and months could bring significant shake-ups in the COVID-19 vaccine landscape. Stay tuned.