If this refers to the same study I've seen news of, it points out that the key difference between its results and studies indication hydroxychloroquine was ineffective is that this study administered the drug early, while other studies administered to patients in desperate straits. Hydroxychloroquine acts to hinder the virus from invading cells. i.e. to hinder/stop the spread of the infection. IOW, it should be administered early, not late in the disease process. And as many have noted, azithromycin and some form of zinc should be used at the same time to prevent/treat certain dangerous symptoms.