The race to produce antiviral pills — for COVID-19 — includes Pfizer, Merck, and other drugmakers

• Pfizer hopes its oral antiviral drug for COVID-19 could be prescribed at the first sign of infection or exposure.
• The drug would prevent symptomatic disease in those who have been exposed and inhibit the onset of infection in others.

• Several other drugmakers like Merck and Ridgeback Biotherapeutics are developing antivirals.

The race to develop an antiviral pill for COVID-19 is on.

Pfizer announced Monday that it has launched a large-scale study testing its investigational oral antiviral drug for COVID-19 prevention.

How does the new Pfizer drug work?

Pfizer’s drug, PF-07321332, is being tested on up to 2,660 healthy adults aged 18 and older who live in the same homes as people with confirmed COVID-19 infections. The drug is designed to be administered orally, which would block a key enzyme that the coronavirus needs to replicate.

It would be taken with a low dose of ritonavir, an older drug used to treat HIV infection, which would then help slow the metabolism of PF-07321332 in hopes that the drug will remain active in the body for longer periods of time.

The company said it could potentially be prescribed at the first sign of infection or at first awareness of exposure without requiring hospitalization.

“With the continued impact of COVID-19 around the world, we believe that tackling the virus will require effective treatments for people who contract, or have been exposed to, the virus, complementing the impact that vaccines have had in helping quell infections. If successful, we believe this therapy could help stop the virus early — before it has had a chance to replicate extensively — potentially preventing symptomatic disease in those who have been exposed and inhibiting the onset of infection in others,” Mikael Dolsten, Chief Scientific Officer and President, Worldwide Research, Development and Medical of Pfizer, said in a statement.

Competition among antiviral pill producers

Pfizer isn’t the only drugmaker looking to produce an antiviral to battle COVID-19.

Merck & Co. and Ridgeback Biotherapeutics are also contenders in the oral antiviral pill race. Both companies currently have samples being tested in clinical trials. In addition, Roche and Atea Pharmaceuticals are developing an antiviral pill called AT-527 developed.

These drugs are different from remdesivir, the only antiviral drug that has been approved to treat COVID-19. Remdesivir is only given to patients that are seriously ill or hospitalized; it’s not a drug that can be packaged.

The pill could be here soon

As the world awaits results from these trials, Pfizer Chairman and CEO Albert Bourla told CNBC’s “Squawk Box” that an antiviral pill could be here sooner than we think.

“If all goes well and we implement the same speed that we did so far, and we are, and if regulators also do the same and they are, I hope by the end of the year,” Bourla said.

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