This sounds like the pharmacology version of "you're not holding it right". Supposedly HCQ works because it is a Zinc Ionophore, facilitating intracellular zinc ion transport. Therefore you need zinc ions to transport. But zinc ions exist in the blood of humans. But some humans might be zinc deficient. But you can draw blood and measure their zinc ion concentration and then provide supplemental zinc. So to end up having done a whole study on HCQ efficacy but NOT covered the bases on "zinc needed" seems unbelievable.