Moderna (MRNA 2.57%) is leading the coronavirus vaccine market today -- but this isn't a short-term story. This biotech aims to make itself a leader in the next stages of the coronavirus situation -- first, the pandemic shifts to endemic; then, even farther down the road, as a provider of annual vaccination to people around the world.

Moderna already has its plan in the works. The next step is a bivalent booster. This is a shot that covers more than one virus or strain. Recently, the company even announced positive data from a trial of its first such candidate. Moderna is working on a combined coronavirus and flu vaccine candidate too. But Moderna isn't alone here. Rival vaccine maker Novavax (NVAX -2.91%) also is moving forward with a post-pandemic program. Could Novavax's recent good news upset Moderna's prospects? Let's find out.

A healthcare worker prepares a dose of vaccine.

Image source: Getty Images.

Where the players stand today

First, let's look at where each of these players stand today. Moderna clearly is way ahead of Novavax when it comes to coronavirus protection today. The company launched its vaccine in December of 2020. And since, it's generated billion-dollar revenue and profit. Moderna predicts $21 billion in vaccine revenue this year according to advance purchase agreements signed so far.

Novavax fell behind in its regulatory submissions. It's first authorizations began rolling in at the end of 2021. Today, more than 35 countries have authorized the vaccine. But Novavax still is waiting for a nod from the U.S. This element has weighed on the shares. They've lost 40% since the start of the year. Even so, Novavax has forecast revenue this year of $4 billion to $5 billion from its coronavirus vaccine. That's big -- especially considering this is Novavax's first and only commercialized product.

Novavax's situation is brightening. But it still is far from being a threat to Moderna today. Where Novavax could step ahead is in the following area: the combined coronavirus-flu vaccine program. And this brings me back to the news that could represent a threat for Moderna.

Novavax recently reported positive initial results from a phase 1/2 study of its combined candidate. The candidate was well-tolerated and stimulates immune response. Novavax's next step is a phase 2 dose confirmation trial set to start by the end of this year.

Moderna's combined candidate

Moderna hasn't yet begun clinical studies for its combined candidate. Its work remains in the preclinical stage. So Moderna is behind from a timeline perspective. Things also look more positive for Novavax from a scientific perspective. Novavax's candidate combines two individual components that already have successfully made it through clinical development. One is Novavax's coronavirus vaccine. And the other is NanoFlu --  Novavax's flu vaccine candidate that met all primary endpoints in a phase 3 trial back in 2020.

Moderna has proved itself when it comes to coronavirus protection. But the company isn't yet an expert in flu vaccines. Moderna's most advanced flu vaccine candidate is in phase 2 trials. Data so far have been positive. But there was one bit of news that wasn't so great: The vaccine candidate was associated with more side effects than a currently approved vaccine. This could represent a challenge for Moderna as it combines the flu candidate with the coronavirus element in preparation for clinical trials.

All of this means that, right now, Novavax's path toward a combined vaccine looks smoother than that of Moderna. And a combined vaccine could be a big product in a post pandemic world. That's because it's likely to attract the individuals who typically go for an annual flu shot. Last year, that was about half of American adults. This sort of shot could become the blockbuster coronavirus product of the future. And what's most exciting is that it would represent recurring annual revenue.

A step ahead

So, does Novavax's position here so far mean trouble for Moderna? Not necessarily. I've been saying for a while that Novavax is a step ahead when it comes to a combined vaccine. But this doesn't make me pessimistic about Moderna's future. First of all, there's room for more than one combined vaccine. We've seen that Moderna and Pfizer, as makers of the first two authorized vaccines in the U.S., both have been able to generate blockbuster revenue.

But, most importantly, Moderna has a solid pipeline covering a variety of therapeutic areas. And two potential blockbusters recently entered phase 3 studies: a cytomegalovirus (CMV) vaccine candidate and a respiratory syncytial virus (RSV) vaccine candidate.

All of this means I would look at Novavax's latest news as great news for Novavax -- but it wouldn't make me worry about Moderna's revenue prospects.