https://www.medrxiv.org/content/10.1101/2021.04.19.21255441v1.full.pdf
Here's an interesting study of a drug that appears to be reducing the rate of severe covid, but with a catch.
Nitazoxanide is a thiazolide drug that has been shown to have antiviral activity in the past, although it's primary use in the US is to treat giardiasis.
The design of the study was to randomize 379 people to receiving 600 mg nitazoxanide twice daily for five days or the same number of placebo pills. Only people with symptom onset in the last 72 hours were enrolled, so the idea is to start treatment early and see if the drug reduces progression to hospitalization.
Eight patients progressed to severe covid requiring hospitalization, all considered high risk at the outset. Seven of them were in the placebo group. That's really good -- 85% reduction of severe covid. And it's a well-designed study. They even gave all subjects vitamin B pills, because the drug colors the urine, and the vitamin B maintains the blinding by coloring everyone's urine.
So what's the catch? The price of the generic is about $440 on Goodrx, which is usually the cheapest place to find drugs. The name brand stuff is more like $1800. The dosage is about twice what is used to treat giardiasis.
Because it has to be given in the first 72 hours after symptom onset, we can't just give it to the people who have severe symptoms. But it still might be something that could be given to those at highest risk. The monoclonal antibody drugs being used to treat high risk people aren't cheap either.
There is also the strange observation that the only person in the study who died of covid was the one person who got severe covid in spite of taking the drug. It might be coincidence, but it would be nice to have a larger study on that.