This seems to be the response to every trial that shows chloroquine and friends to be ineffective, though. "Well, of course there was no positive effect, the dose was too low." "Well, of course there was no positive effect, the dose was too high". "Well, of course there was no positive effect, you didn't tape a halibut to the patient's head". "No, not a cooked one, you fools, a live one!"

At a certain point, it's possibly worth considering that there may be no there there.