See my post number 62. One pill does not equal one completely treated American, unlike what several here on FG seem to think. We’re going to need more than just 143K sets worth for treatment between now and when we get a working vaccine.
I am not a doctor and have no idea how many doses are needed for a full treatment. I am sure the experts have determined what the projected cases numbers will need treatment. By multiplying that number by the doses needed for treatment will be a way to guess the number of doses needed. Another thought is we will not need all of that medicine at one time. There is a range of time that the infected will be treated. All we need is stay ahead of the curve.