The market's a forward-looking mechanism, and some people might feel that the COVID-19 pandemic is "over." That's probably an exaggeration. While vaccinations will hopefully reduce the danger, the virus will continue to mutate, and healthcare companies will continue to fight it. Read more to see why three Fool.com contributors think COVID stocks Fulgent Genetics (FLGT 0.10%)NRx Pharmaceuticals (NRXP -27.75%), and Adaptive Biotechnologies (ADPT -4.30%) could double your money this year.

Testing. Testing. Will this stock turn on?

Patrick Bafuma (Fulgent Genetics): Entering the last wave of 2021, you may have heard that there was a run on COVID tests. In fact, just this week, the local CVS told me that there was not an over-the-counter test available within 20 miles. Yet many countries, ports, and employers want the results of a PCR test within three days prior to entry. While this may put a strain on resources, it's great news for RT-PCR test maker Fulgent Genetics.

Three researchers take notes as they examine test tubes in a lab.

Image source: Getty Images.

This medical diagnostics company has focused on contracting with school systems, nursing homes, athletic organizations, health clinics, and the government to commercialize highly specific PCR testing for the SARS-CoV-2 virus. Having booked $95.5 million in revenue in the third quarter, it is likely safe to assume this will continue with the omicron variant well into the new year. Adjusted gross margin was a juicy 81.3% in Q3 2021, too. Over the last year, margin has floated between 77.1% and 82.6%, so aside from inflationary issues, I have little reason to think the margin will not remain enviable. And while it's clear that currently, the company's future remains tethered to COVID-19, it has also been clear that the virus refuses to go away. As such, I'm not convinced that COVID diagnostic numbers will melt away for the company. And with short interest now at just under 13%, positive results for the company could take shareholders on an enjoyable trip up and to the right.

With a price-to-earnings (P/E) ratio of just over 5, this stock looks insanely cheap. When compared to classic lab vendors like Laboratory Corporation of America Holdings and Quest Diagnostics, with P/E ratios of 10.9 and 10.2 respectively, or Abbott Laboratories and its Binax test at a P/E of about 35, Fulgent looks significantly undervalued. With a P/E in the mid-single digits and what seems like a never-ending need for its product, Fulgent Genetics could be an easy double in 2022.

A healthy rebound could be taking shape

George Budwell (NRx Pharmaceuticals): NRx Pharmaceuticals' stock shed an eye-popping 80.4% of its value over 2021. Although the drugmaker's shares initially popped during the first few months of 2021, Wall Street's enthusiasm for this speculative coronavirus stock steadily waned as the year progressed thanks to the U.S. Food and Drug Administration (FDA) declining to grant Emergency Use Authorization (EUA) for the company's severe COVID-19 treatment, Zyesami (aviptadil). The long and short of it is that Zyesami probably would have racked up several hundred million dollars in sales with an EUA for severe COVID-19 cases. That's a tremendous commercial opportunity for a company with market cap under $300 million at the time of this writing. 

The good news is that NRx Pharmaceuticals recently filed a new Breakthrough Therapy Designation (BTD) request for Zyesami with the FDA. This revised BTD request centers around COVID-19 respiratory failure in patients who progress despite treatment with remdesivir and other approved therapies. If granted, this regulatory designation might open the door for an EUA in this patient population. While this revised target market is certainly smaller in scope, it would still amount to a healthy commercial opportunity for a company of NRx Pharmaceuticals' current size. In fact, NRx Pharmaceuticals ought to be able to bank at least $100 million in sales this year if the FDA gives the green light this time around. 

The big picture is that this beaten-down coronavirus stock might be gearing up for a monstrous run higher in 2022.  

Adaptive Biotechnologies will bounce back

Taylor Carmichael (Adaptive Biotechnologies): Adaptive Biotechnologies is focused on the immune system. The company is mapping 30 billion immune receptors in the human body and is using supercomputers from Microsoft to run the data as it maps our adaptive immune system. Later this decade, Adaptive says it could have a universal blood test on the market: A doctor will take a blood sample and be able to "hack" your immune system and see what diseases it is fighting. This blood test could reveal if you have infectious diseases, autoimmune disorders, or cancer. 

In the meantime, Adaptive already has several diagnostic tests on the market. The FDA has cleared three of the company's clonoSEQ tests for minimal residual disease in blood cancers (multiple myeloma, acute lymphoblastic leukemia, and chronic lymphocytic leukemia). And the company has an EUA for its COVID-19 test.

Adaptive's COVID test is the first on the market that uses T cells in the blood to check for the disease. Just recently the Molecular Diagnostic Services Program agreed to pay $770 per test for certain groups of individuals, including immunocompromised patients.

Adaptive's not profitable yet, and its revenue is still meager: $146 million over the trailing 12 months. The stock is down 50% as impatient investors head for the exits. But that's a mistake. The company estimates there are 7 million immunocompromised patients just in the U.S. That's a $5 billion market opportunity in the near term. With the government paying for the tests, we should see a spike in Adaptive's COVID-related revenue in 2022, and the stock should jump along with it.