To be sure, no drug has yet been proven to be effective in treating novel coronavirus disease COVID-19. Any claims that you might read online about one drug or another being a silver bullet for the disease are premature at best. However, what is true right now is that several companies are developing therapies that hold the potential to be effective at treating COVID-19.

Two of the players at the forefront of these efforts are Emergent BioSolutions (EBS -4.80%) and Gilead Sciences (GILD 0.07%). Both biotech stocks have been winners so far in 2020 while most stocks have plunged. Which is the better pick for long-term investors?

Pill with COVID-19 printed on it

Image source: Getty Images.

The case for Emergent BioSolutions

If there's any company that is built for crises like the coronavirus pandemic, it's Emergent BioSolutions. The company's primary focus is developing products that address public health threats. Its biggest customer, by far, is the U.S. government.

Emergent BioSolutions' current lineup includes 10 products. Four of them are vaccines for protection against anthrax, cholera, smallpox, and typhoid. Another four are drugs that are used to treat patients with anthrax, botulism, and smallpox. The company also markets devices for emergency treatment of opioid overdoses and for removing or neutralizing several chemical warfare agents from the skin.

The company also has several products in its pipeline that could be available in the not-too-distant future. These include a pediatric cholera vaccine that's currently in late-stage testing and the Trobiguard auto-injector for potential use as a nerve agent countermeasure. Emergent BioSolutions is also developing experimental anthrax, Chikungunya virus, flu, and Zika vaccines.

There are two ways that Emergent BioSolutions is working to fight COVID-19. It's developing a plasma-derived hyperimmune therapy targeting COVID-19 in partnership with the U.S. government. The company also teamed up with Novavax on the small biotech's COVID-19 vaccine development.

Emergent BioSolutions' revenue soared 41% year over year in 2019. The consensus among Wall Street analysts is that the biotech will increase its earnings by more than 9% on average annually over the next five years.   

The case for Gilead Sciences

Gilead Sciences just might have the most promising COVID-19 drug in development. A top World Health Organization (WHO) official stated in late February that Gilead's remdesivir was the "one drug right now that we think may have efficacy." More than 1,700 patients with COVID-19 have been treated so far with remdesivir under compassionate-use and expanded-access programs. 

While Gilead awaits the results from ongoing late-stage clinical trials evaluating remdesivir, it's already shifting into high gear to produce the drug. The big biotech has ramped up its production capacity and expects to be able to make more than 500,000 treatment courses of the antiviral drug by October and more than 1 million by the end of the year.

In the meantime, Gilead is a leader in other arenas. The company has dominated the HIV market for years. Its latest HIV drug, Biktarvy, appears to be on track to be Gilead's biggest winner yet. Thanks to the 2017 acquisition of Kite Pharma, Gilead is a leader in cancer cell therapies. And the company's hepatitis C virus (HCV) franchise enjoys a virtual duopoly with AbbVie (ABBV -1.03%), although sales have fallen in large part because there are fewer new patients now that so many patients with HCV have been cured.

Perhaps the most exciting thing about Gilead is its pipeline. The crown jewel right now is filgotinib. Gilead awaits regulatory approvals for the drug in treating rheumatoid arthritis. Its pipeline also features several other promising candidates, notably including long-acting HIV capsid GS-6207 and cancer cell therapy KTE-X19.

Gilead's revenue increased only 1.5% year over year in 2019. However, its growth should pick up assuming filgotinib wins U.S. and European approvals. Gilead also offers a strong dividend which currently yields close to 3.5%.

Better pick

I think that both of these stocks should be on investors' radar screens. My favorite, though, is Gilead Sciences.

I like Gilead's prospects with filgotinib. I like its dividend. And with shares trading at only 11.4 times expected earnings, the stock is priced attractively. Gilead may or may not be successful with its coronavirus drug, but I expect the stock to be a winner over the long run either way.