I think it may have been this one...although 1200mg daily dose
Brazil study https://www.medrxiv.org/content/10.1101/2020.04.07.20056424v2
Eligible participants were allocated to receive orally or via nasogastric tube high dose CQ (600mg CQ twice daily for 10 days or total dose 12g); or low dose CQ (450mg for 5 days, twice daily only on the first day, or total dose 2.7g).
That was in Brazil; LJ’s looking for any study that was done in the u.s., that used excessive dosages.