8 lingering questions about the new Covid pills from Merck and Pfizer – Stat News

“We’re accelerating our path out of this pandemic,” President Biden said after data on the second Covid pill became available.

The first results, from Merck and Ridgeback Therapeutics, were released in October and will be considered by an advisory panel to the Food and Drug Administration in December.

In November, Pfizer announced that its Covid pill, Paxlovid, reduced hospitalizations by 89% and also prevented deaths in its own large randomized study.

The companies have only issued data in press releases, not scientific articles, and doctors need to know a lot more about both.

At the headline level, Pfizer’s pill reduced the risk of hospitalization and death by 89%, while Merck showed a reduction of 50%.

The studies enrolled similar populations — unvaccinated people with mild to moderate Covid-19 and at least one risk factor for severe disease — but they had slightly different measures of efficacy.

In each study, fewer patients in the treatment group left the study due to side effects compared to those in the placebo group.

Combinations of antiviral drugs are the standard treatment for people with HIV because it reduces the risk of resistance caused by mutations in the virus.

Nahid Bhadelia, the founding director of the Center for Emerging Infectious Diseases Policy and Research at Boston University, also supports the idea of clinical trials to test combination treatments.

A third antiviral pill, from the biotech firm Atea and the large drug firm Roche, failed to prove it was effective in its own study, and Wall Street analysts suspect the reason is that the companies included vaccinated patients in the research.

Pfizer is running a clinical trial, with results due next year, that does include vaccinated patients, and the company’s executives have expressed confidence based on the results so far that the treatment should work.

The modification is so subtle that not only will the coronavirus use molnupiravir in place of other building blocks when it replicates itself, but coronaviruses’ unusual proofreading mechanism can’t even pick up on the imposter compound.

“Ultimately, this leads to what’s known as error catastrophe.

Like a bolt of fabric before it’s cut to a clothing pattern, this protein needs to be chopped down to size before it can work.

The drug is designed to bind to a particularly important point in an enzyme called a protease which slices up proteins.

The body’s defense mechanisms will get rid of anything that it doesn’t recognize — including drugs, which can be digested by enzymes in a person’s liver.

In a Phase 3 study enrolling recently diagnosed patients at high risk for severe disease, Regeneron’s treatment reduced the risk of hospitalization or death by 70% compared to placebo.

That could make the treatments from Pfizer and Merck, taken orally at home, preferable to patients unable to visit an infusion center.

Regeneron and Lilly have signed deals with the federal government to sell their treatments at about $1,250 per dose.

A pill is a huge leap in terms of logistical ease over infused therapies like monoclonal antibodies.

PCR tests can take days to return a result, and though the Biden administration has upped its effort to expand the availability of at-home rapid tests, finding one at a store is still hit or miss — success feels like scoring this holiday season’s hottest gift.

But there’s a theoretical chance that molnupiravir could also influence normal human DNA when it replicates, too.

But UNC’s Swanstrom isn’t completely convinced that the tests Merck did were sensitive enough.

It could be no worse than going to get a dental X-ray — or it could do something more.

Because the new antiviral Pfizer is developing is a protease inhibitor, infectious disease specialists are familiar with how it works.

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