Key Points

  • Moderna and Pfizer are about a month away from possible Emergency Use Authorization submissions for their investigational coronavirus vaccines.
  • The companies expect initial readouts from their phase 3 trials later this month.
  • Moderna and Pfizer and have reported positive earlier stage data in young and older trial participants.

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"It was the best of times, it was the worst of times..." That's how Charles Dickens' A Tale of Two Cities begins. And that describes Moderna (NASDAQ:MRNA) and Pfizer's (NYSE:PFE) situations today. The pandemic definitely makes this time one of the worst in recent memory. But against the coronavirus backdrop, some leaders in the vaccine race are experiencing their best moments. 

Ten programs are currently involved in phase 3 trials. But Moderna and Pfizer are arguably the closest to earning Emergency Use Authorizations (EUAs) for their vaccine candidates. Both expect trial readouts around the end of the month, and interestingly, both players aren't developing traditional vaccines. Instead, their candidates use messenger RNA (mRNA) technology. Let's take a closer look at each company's development path so far -- and what may lie ahead.

Gloved clinician administers a vaccine to a patient, who wears a mask and a grey t-shirt with sleeve rolled up.

Image source: Getty Images


Moderna took center stage when, in March, it became the first company to start human trials in a coronavirus vaccine candidate. The company's path since then has been smooth, starting with positive phase 1 trial data. Here's what we know so far: In a study of 45 volunteers aged 18 through 55, all participants who received the vaccine candidate produced neutralizing antibodies. These antibodies are key, because their role is to block infection. In the group given the dose that would later be used in the phase 3 trial, neutralizing antibody levels were 2.1 to 4.1 times higher than those of recovered COVID-19 patients.

Later, a look specifically at older adults -- aged 56 through 70 and 71 and older -- showed the more vulnerable population also created antibodies. Participants produced neutralizing antibody levels two to three times higher than those of the recovered patients.

Moderna began its phase 3 study in July. By late October, the company completed the enrollment of 30,000 volunteers. At that time, more than 25,650 participants had received their second vaccination in the two-dose schedule. Moderna now must provide the U.S. Food and Drug Administration (FDA) with two-month follow-up data on at least half of trial participants. CEO Stephane Bancel says that schedule means that Moderna can't request an EUA before Nov. 25. Investors should keep an eye on whether the interim results released at the end of the month include efficacy data in addition to information on the candidate's safety profile. 


Pfizer jumped into the game a bit later than Moderna. The big pharma joined forces with German biotech BioNTech (NASDAQ:BNTX) in March, and the partners began their phase 1/2 trial a month later. If their vaccine candidate is approved, Pfizer's commercial power will help distribute BioNTech's mRNA drug all over the world. Interim results from the early-stage trial involving about 120 participants were positive. Like Moderna, Pfizer and BioNTech have marched steadily along to phase 3.

The company began testing four candidates, then decided to advance one: BNT162b2. In participants ages 18 through 55, the investigational vaccine produced neutralizing antibody levels 3.8 times higher than those in recovered coronavirus patients. In participants aged 65 through 85, levels were 1.6 times higher than the recovered patients. In September, the partners amended their phase 3 trial protocol to expand enrollment to 44,000 participants from the initial plan of 30,000. As of Nov. 2, there were more than 37,000 participants enrolled.

Like Moderna, Pfizer and BioNTech must submit two months of follow-up data on half of the phase 3 trial participants. Pfizer CEO Albert Bourla said recently that those results would be ready during the third week of November. If data are positive, Pfizer will apply for an EUA "soon after," according to Bourla.

A new kind of vaccine

From timeline and data quality perspectives, Moderna and Pfizer are, so far, on par. And if one or both of them make it to the finish line, they will introduce a vaccine unlike any other on the market. Usually, vaccines work by delivering a weakened form of virus into the body. This allows the body to build up antibodies to fight infection.

But Moderna's and Pfizer's candidates work differently by harnessing the power of mRNA. These investigational vaccines use mRNA to deliver instructions to produce a protein from the virus, and the immune system creates antibodies to the protein just like it would if a weakened form of the virus was injected. Success of one of these vaccines would not only address the coronavirus. It also would be a huge victory for mRNA medicine. These would be the first vaccines of this type to be commercialized.

Now, what about funding and production capacity? There, too, Moderna and Pfizer are neck and neck. In August, Operation Warp Speed (OWS), the government effort to shepherd a vaccine to market, offered Moderna $1.5 billion for the delivery of vaccine doses, contingent on its approval. The government initiative had already granted Moderna up to $483 million in funding for its program. OWS awarded as much as $1.95 billion to Pfizer for vaccine doses.

As for capacity, Moderna is aiming to produce 500 million to possibly 1 billion doses annually as of next year. Pfizer's goal is to produce about 1.3 billion doses by the end of next year.

What does this mean for investors?

Moderna and Pfizer are about equal in this late stage of the vaccine race. One of them may win. Or both of them may take a piece of the coronavirus market prize. The global need for a vaccine means there is room for more than one vaccine maker to reap the benefits. It's also possible both will fail. Anything can happen in clinical trials.

It's not too late to take a position in these stocks and bet on the future of mRNA vaccines. Investors with low risk tolerance, however, should either watch from the sidelines -- or opt for Pfizer over Moderna. The big pharma's vast array of commercialized products means it won't depend on a coronavirus vaccine for revenue and share performance. Clinical stage Moderna depends on the success of its coronavirus vaccine candidate, at least for now.

Whatever happens at the end of this month will be crucial for Moderna and Pfizer. But this tale of two companies may not be over then. It could be just the beginning.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.