I don't understand how they can ethically justify not including a control arm. There's no knowledge about benefit here, so any treatment is pretty speculative - even if there's a benefit in one of the arms we still won't really have much info on whether it works
I'd say for this a control arm would be usual care at the very least, probably including some other speculative medication. Otherwise we simply won't know if remsividir is better than anything else, we'll just know whether 5-days beats 10-days