You might have thought the coronavirus vaccine race ended when Pfizer (NYSE:PFE) crossed the finish line first in December. But there's a new vaccine race underway. And that's the race to prove that a vaccine can protect against new viral strains. Variants from Brazil, the U.K., and South Africa worry the scientific community (and the rest of us) the most at the moment. But it's possible that new variants of concern will arise down the road.

Johnson & Johnson (NYSE:JNJ) highlighted exactly how its investigational vaccine performed against those new strains in its phase 3 trial. A U.S. Food and Drug Administration (FDA) advisory committee meets on Feb. 26 to discuss possible Emergency Use Authorization (EUA) for that candidate.

But Johnson & Johnson isn't alone. Other companies are showing us how their vaccines can conquer new strains -- or are developing new ways to do the job. Here's a look at some of the noteworthy players in this new race.

IMAGE SOURCE: GETTY IMAGES.

Johnson & Johnson

Johnson & Johnson's phase 3 clinical trial unfolded as the troubling strains gathered force. That allowed the company to measure how its investigational vaccine performed versus these strains in a real-world setting. The result? The candidate showed 66% efficacy in Latin America (where the Brazilian strain is common) and 57% efficacy in South Africa (home of the South African strain). The vaccine demonstrated 72% efficacy in the U.S., where cases of the U.K. strain are still on the rise.

This is rather positive news for two reasons. First, unlike its major rivals, Johnson & Johnson has developed a one-dose candidate, so this level of efficacy after just one dose is great. Also, the FDA originally set a bar for EUA at 50% efficacy or better -- and Johnson & Johnson surpasses this mark even against the South African strain.

Moderna

Moderna's (NASDAQ:MRNA) vaccine is already on the market. The biotech company tested the product in vitro against the U.K. and South African strains and found that it's still protective. But Moderna isn't stopping there: It's investigating two possible boosters to further increase immunity.

One of the boosters would be a third dose of vaccine -- the idea is that it could further lift levels of neutralizing antibodies, which block infection. The second booster under investigation is one that would specifically target the South African strain. If this second booster works, Moderna could update it as new variants of concern arise. Moderna says it's moving this strain-specific booster into preclinical and phase 1 trials.

Novavax

Novavax's (NASDAQ:NVAX) phase 3 U.K. trial and phase 2b South African trial allowed the company to see how its vaccine candidate handled variants common in each country. The trials showed 85.6% efficacy against the U.K. strain and 60% efficacy against the South African strain.

Like Moderna, Novavax plans on increasing its chances of effectively handling new strains. The company said it's working on a booster or vaccine candidate that can target more than one strain. It expects to start clinical testing of candidates in the second quarter of this year.

Gritstone Oncology

Gritstone Oncology (NASDAQ:GRTS) is farther from the finish line than the rivals mentioned above. The company recently signed an agreement with the National Institute of Allergy and Infectious Diseases to launch clinical trials.

Today's vaccines target the spike protein of the original coronavirus. This is the protein that infects healthy cells. Gritstone's investigational vaccine includes not only spike protein antigen, but also other viral antigens. That way, even if mutations greatly transform the coronavirus' spike protein, our immune systems will recognize the other antigens. That may make the Gritstone candidate more efficacious against new strains than vaccines targeting only the spike protein. Preclinical studies were encouraging, showing high levels of neutralizing antibodies and immune-system responses.

Ocugen

Ocugen (NASDAQ:OCGN) recently finalized an agreement allowing it to co-develop and commercialize Bharat Biotech International's investigational vaccine in the U.S. Bharat recently won emergency authorization in its home country of India.

The product, Covaxin, has resulted in lasting immune responses to various viral proteins and shown neutralizing capabilities across strains, according to Ocugen's CEO. Bharat hasn't yet reported phase 3 data, but earlier this year, said it would do so by March. Ocugen has started talks with the FDA regarding a path to EUA. But it isn't clear how long the process will take.

CureVac

CureVac (NASDAQ:CVAC) began the pivotal trial of its coronavirus vaccine candidate in December. The company, like Pfizer and Moderna, is working on a messenger RNA (mRNA) vaccine. More recently, CureVac partnered with the U.K. government to develop potential vaccines to handle coronavirus variants. Any vaccine resulting from the partnership initially would be produced and distributed in the U.K.

CureVac said its current vaccine program "will benefit" from work on this new project. The company didn't offer details, but we can imagine a couple of options, including adding a new-strain vaccine candidate as a booster to the current investigational vaccine.

What does all this mean for investors?

Each of these programs offers at least one compelling element. But at this stage, I'm most confident about those closest to the finish line: Johnson & Johnson, Moderna, and Novavax. I don't expect Johnson & Johnson to offer investors big gains from its progress, though. The company doesn't plan to benefit from vaccine sales during the pandemic, and it's hard for a company with a $435 billion market cap to make major moves in terms of share price.

Moderna is closest to the finish line in this new race -- in the U.S. The biotech company has already launched studies of its boosters. And it has a recent new advantage: The Biden administration just bought enough vaccine doses to immunize all Americans from both Moderna and Pfizer. So, if Moderna comes out with a booster, that may truly seal its deal as leader in the U.S. market.

Novavax may become a leader in the international market. The data released from the U.K. and South Africa trials showed good performance against variants of concern. A possible booster may move the needle from "good" to "excellent."