Two of the biggest biotechs stand at the forefront of the race to find an effective treatment for COVID-19, the disease caused by novel coronavirus SARS-CoV-2. Gilead Sciences (GILD -0.44%) and Regeneron Pharmaceuticals (REGN -0.58%) both hope to give people around the world a reason to be optimistic that the deadly disease can be treated.

Shares of both Gilead and Regeneron have risen so far this year while the overall stock market has crashed. But which of these coronavirus-focused stocks is the better choice for long-term investors? 

Pill with COVID-19 printed on it

Image source: Getty Images.

The case for Gilead Sciences

Gilead is without question the leader in developing a treatment for COVID-19, at least for now. The company's antiviral drug remdesivir, originally developed for treating Ebola, is already in late-stage clinical studies in treating COVID-19.

Although remdesivir wasn't effective as an Ebola treatment, the drug has shown promise in the past in treating MERS and SARS, both of which are members of the coronavirus family. World Health Organization (WHO) assistant director-general Bruce Aylward even stated in late February that Gilead's experimental drug is the "one drug right now that we think may have efficacy."

It's still too soon to know if remdesivir will pan out in treating COVID-19. Some really early results dampened enthusiasm about the prospects for the drug due to possible safety issues, although forming an opinion based on those results isn't advisable. Neither is it a good idea to assume that remdesivir will be successful based on anecdotal evidence that it's helped some patients infected with the novel coronavirus recover from COVID-19.

There are other reasons to like Gilead in addition to its coronavirus program. The company dominates the HIV market with powerhouse drugs including Biktarvy and Descovy. Gilead is expanding its cancer development program with its pending acquisition of Forty-Seven.

Perhaps the most exciting story for Gilead right now, though, its anticipated entrance into the huge immunology market. Gilead hopes to win U.S. and European approvals for filgotinib in treating rheumatoid arthritis later this year. The company and its partner, Galapagos, are also evaluating the drug in treating other immunology indications. 

Most biotech stocks don't pay dividends, but Gilead does. Its dividend currently yields over 3.8%. Gilead has increased its dividend by 58% since initiating its dividend program in 2015.

The case for Regeneron

Regeneron and its partner, Sanofi, are evaluating rheumatoid arthritis drug Kevzara in a phase 2/3 clinical study for treating patients who develop severe cases of COVID-19. The drug could help reduce inflammation in the lungs that can occur with the disease.

The company also could be onto something even bigger. Regeneron announced on Tuesday that it's working on a coronavirus cocktail of viral-neuralizing antibodies. Clinical testing of the therapy should begin by early summer. It's possible that the cocktail could be given prior to exposure to the coronavirus to protect against infection as well as to individuals who have already been infected as a treatment for COVID-19.

It might not take very long for Regeneron to know if its efforts are successful. CEO Leonard Schleifer thinks that initial results will be available within a few weeks after patients are enrolled in its study of Kevzara. Regeneron hopes to move rapidly with enrollment over the next month. 

In the meantime, the biotech has a lot more on its plate. Regeneron launched its Eylea pre-filled syringe in December. The eye-disease drug is the company's biggest moneymaker. It awaits U.S. and European approvals of Dupixent in treating children ages six to 11 with moderate-to-severe atopic dermatitis. 

Regeneron also has key regulatory filings on the way in 2020. The company intends to submit for FDA and EMA approval of evinacumab in treating homozygous familial hypercholesterolemia (HoFH). It also anticipates completing a rolling FDA submission for REGN-EB3, its multi-antibody therapy to Ebola. 

In addition, Regeneron should have several important pipeline milestones in the coming months. These include reporting results from a late-stage study of Dupixent in treating pediatric patients with asthma, announcing results from a potentially pivotal phase 2 study of Libtayo in treating basal cell carcinoma, and reporting late-stage results for fasinumab in treating osteoarthritis pain of the knee or hip. 

Better coronavirus stock

While both of these biotechs have a lot of promise, my view is that Gilead is the better stock to buy right now. I don't know if remdesivir will be effective in treating COVID-19, but I'm cautiously optimistic. I feel pretty good, though, about the chances for filgotinib. I also like Gilead's dividend which boosts the total return the stock delivers. And with its shares trading at less than 12 times expected earnings, Gilead is dirt cheap.